WorldWideScience

Sample records for plasma quench production

  1. Plasma quench production of titanium from titanium tetrachloride

    Energy Technology Data Exchange (ETDEWEB)

    Sears, J.W.

    1994-10-01

    This project, Plasma Quench Production of Titanium from Titanium Tetrachloride, centers on developing a technique for rapidly quenching the high temperature metal species and preventing back reactions with the halide. The quenching technique chosen uses the temperature drop produced in a converging/diverging supersonic nozzle. The rapid quench provided by this nozzle prevents the back reaction of the halide and metal. The nature of the process produces nanosized particles (10 to 100 nm). The powders are collected by cyclone separators, the hydrogen flared, and the acid scrubbed. Aluminum and titanium powders have been produced in the laboratory-scale device at 1 gram per hour. Efforts to date to scale up this process have not been successful.

  2. Titanium Metal Powder Production by the Plasma Quench Process

    Energy Technology Data Exchange (ETDEWEB)

    R. A. Cordes; A. Donaldson

    2000-09-01

    The goals of this project included the scale-up of the titanium hydride production process to a production rate of 50 kg/hr at a purity level of 99+%. This goal was to be achieved by incrementally increasing the production capability of a series of reactor systems. This methodic approach was designed to allow Idaho Titanium Technologies to systematically address the engineering issues associated with plasma system performance, and powder collection system design and performance. With quality powder available, actual fabrication with the titanium hydride was to be pursued. Finally, with a successful titanium production system in place, the production of titanium aluminide was to be pursued by the simultaneously injection of titanium and aluminum precursors into the reactor system. Some significant accomplishments of the project are: A unique and revolutionary torch/reactor capable of withstanding temperatures up to 5000 C with high thermal efficiency has been operated. The dissociation of titanium tetrachloride into titanium powder and HC1 has been demonstrated, and a one-megawatt reactor potentially capable of producing 100 pounds per hour has been built, but not yet operated at the powder level. The removal of residual subchlorides and adsorbed HC1 and the sintering of powder to form solid bodies have been demonstrated. The production system has been operated at production rates up to 40 pounds per hour. Subsequent to the end of the project, Idaho Titanium Technologies demonstrated that titanium hydride powder can indeed be sintered into solid titanium metal at 1500 C without sintering aids.

  3. Characterization of plasma current quench during disruption in EAST tokamak

    Institute of Scientific and Technical Information of China (English)

    陈大龙; 沈飙; 杨飞; 钱金平; 肖炳甲

    2015-01-01

    Preliminary analysis of plasma current quench is presented in this paper based on the disruption database. It demon-strates that 26.8%discharges have disrupted in the last 2012 campaign, in addition, plasma disruptive rate grows with the increase of plasma current. Best-fit linear and instantaneous plasma current quench rate is extracted from the recent EAST disruptions, showing that 80%–30%interval of the maximum plasma current is well fit for EAST device. The lowest area-normalized current quench time is 3.33 ms/m2 with the estimated plasma electron temperature being 7.3 eV∼9.5 eV. In the disruption case the maximum eddy current goes up to 400 kA, and a fraction of currents are respectively driven on upper and lower outer plate with nearly 100 MPa–200 MPa stress in the leg.

  4. Characterization of thermal and current quench of JET plasmas

    Science.gov (United States)

    Riccardo, V.; Barabaschi, P.; Loarte, A.; Sugihara, M.

    2004-11-01

    JET provides crucial scaling points and unique physics access for the extrapolation of disruptions to ITER. Disruption and ELM heat loads influence the selection of materials for plasma facing components (PFCs). Most JET thermal quenches occur when the plasma thermal energy is less than half that at full performance, suggesting a more optimistic life expectancy for ITER PFCs. The exceptions are ITB collapses and pure VDEs, which are also more likely to lead to the shortest thermal quenches. For the fast current quench disruptions, the EM load due to the induced eddy currents represent the most severe electromechanical design condition for in-vessel components. The minimum linear decay time normalised to the plasma cross section extrapolates to a 40 ms disruption for ITER, based on data from JET and most other tokamaks. Some very fast JET events are better fit by an exponential, with the minimum characteristic current decay time scaling to 35 ms for ITER. Contrary to expectations, the quench rate of high and low thermal energy disruptions does not vary substantially.

  5. Model of vertical plasma motion during the current quench

    Science.gov (United States)

    Kiramov, D. I.; Breizman, B. N.

    2017-10-01

    Tokamak disruptions impair plasma position control, which allows the plasma column to move and hit the wall. These detrimental events enhance thermal and mechanical loads due to halo currents and runaway electron losses. Their fundamental understanding and prevention is one of the high-priority items for ITER.

  6. Characterization of the plasma current quench during disruptions in the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gerhardt, S.P., Menard, J.E., and the NSTX Research Team

    2008-12-17

    A detailed analysis of the plasma current quench in the National Spherical Torus Experiment [M.Ono, et al Nuclear Fusion 40, 557 (2000)] is presented. The fastest current quenches are fit better by a linear waveform than an exponential one. Area-normalized current quench times down to .4 msec/m2 have been observed, compared to the minimum of 1.7 msec/m2 recommendation based on conventional aspect ratio tokamaks; as noted in previous ITPA studies, the difference can be explained by the reduced self-inductance at low aspect ratio and high-elongation. The maximum instantaneous dIp/dt is often many times larger than the mean quench rate, and the plasma current before the disruption is often substantially less than the flat-top value. The poloidal field time-derivative during the disruption, which is directly responsible for driving eddy currents, has been recorded at various locations around the vessel. The Ip quench rate, plasma motion, and magnetic geometry all play important roles in determining the rate of poloidal field change.

  7. Analyses of quenching process during turn-off of plasma electrolytic carburizing on carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jie; Liu, Run [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Xue, Wenbin, E-mail: xuewb@bnu.edu.cn [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Wang, Bin; Jin, Xiaoyue; Du, Jiancheng [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2014-10-15

    Highlights: • Cooling rate of carburized steel at the end of PEC treatment is measured. • The quench hardening in the fast or slow turn-off mode hardly takes place. • Decrease of the surface roughness during slow turn-off process is found. • A slow turn-off mode is recommended to replace the conventional turn-off mode. - Abstract: Plasma electrolytic carburizing (PEC) under different turn-off modes was employed to fabricate a hardening layer on carbon steel in glycerol solution without stirring at 380 V for 3 min. The quenching process in fast turn-off mode or slow turn-off mode of power supply was discussed. The temperature in the interior of steel and electron temperature in plasma discharge envelope during the quenching process were evaluated. It was found that the cooling rates of PEC samples in both turn-off modes were below 20 °C/s, because the vapor film boiling around the steel sample reduced the cooling rate greatly in terms of Leidenfrost effect. Thus the quench hardening hardly took place, though the slow turn-off mode slightly decreased the surface roughness of PEC steel. At the end of PEC treatment, the fast turn-off mode used widely at present cannot enhance the surface hardness by quench hardening, and the slow turn-off mode was recommended in order to protect the electronic devices against a large current surge.

  8. Modeling the formation of the quench product in municipal solid waste incineration (MSWI) bottom ash.

    Science.gov (United States)

    Inkaew, Kanawut; Saffarzadeh, Amirhomayoun; Shimaoka, Takayuki

    2016-06-01

    This study investigated changes in bottom ash morphology and mineralogy under lab-scale quenching conditions. The main purpose was to clarify the mechanisms behind the formation of the quench product/layer around bottom ash particles. In the experiments, the unquenched bottom ashes were heated to 300°C for 1h, and were quenched by warm water (65°C) with different simulated conditions. After having filtered and dried, the ashes were analyzed by a combination of methodologies namely, particle size distribution analysis, intact particle and thin-section observation, X-ray diffractometry, and scanning electron microscope with energy dispersive X-ray spectroscopy. The results indicated that after quenching, the morphology and mineralogy of the bottom ash changed significantly. The freshly quenched bottom ash was dominated by a quench product that was characterized by amorphous and microcrystalline calcium-silicate-hydrate (CSH) phases. This product also enclosed tiny minerals, glasses, ceramics, metals, and organic materials. The dominant mineral phases produced by quenching process and detected by XRD were calcite, Friedel's salt, hydrocalumite and portlandite. The formation of quench product was controlled by the fine fraction of the bottom ash (particle size ash-water reactions and formation of the quench product in the bottom ash was proposed.

  9. Analyses of quenching process during turn-off of plasma electrolytic carburizing on carbon steel

    Science.gov (United States)

    Wu, Jie; Liu, Run; Xue, Wenbin; Wang, Bin; Jin, Xiaoyue; Du, Jiancheng

    2014-10-01

    Plasma electrolytic carburizing (PEC) under different turn-off modes was employed to fabricate a hardening layer on carbon steel in glycerol solution without stirring at 380 V for 3 min. The quenching process in fast turn-off mode or slow turn-off mode of power supply was discussed. The temperature in the interior of steel and electron temperature in plasma discharge envelope during the quenching process were evaluated. It was found that the cooling rates of PEC samples in both turn-off modes were below 20 °C/s, because the vapor film boiling around the steel sample reduced the cooling rate greatly in terms of Leidenfrost effect. Thus the quench hardening hardly took place, though the slow turn-off mode slightly decreased the surface roughness of PEC steel. At the end of PEC treatment, the fast turn-off mode used widely at present cannot enhance the surface hardness by quench hardening, and the slow turn-off mode was recommended in order to protect the electronic devices against a large current surge.

  10. Surface properties of low alloy steel treated by plasma nitrocarburizing prior to laser quenching process

    Science.gov (United States)

    Wang, Y. X.; Yan, M. F.; Li, B.; Guo, L. X.; Zhang, C. S.; Zhang, Y. X.; Bai, B.; Chen, L.; Long, Z.; Li, R. W.

    2015-04-01

    Laser quenching (LQ) technique is used as a part of duplex treatments to improve the thickness and hardness of the surface layers of steels. The present study is to investigate the surface properties of low alloy steel treated by plasma nitrocarburizing (PNC) prior to a laser quenching process (PNC+LQ). The microstructure and properties of PNC+LQ layer determined are compared with those obtained by PNC and LQ processes. OM, XRD, SEM and EDS analyses are utilized for microstructure observation, phases identification, morphology observation and chemical composition detection, respectively. Microhardness tester and pin-on-disc tribometer are used to investigate the mechanical properties of the modified layers. Laser quenching of plasma nitrocarburized (PNC+LQ) steel results in much improved thickness and hardness of the modified layer in comparison with the PNC or LQ treated specimens. The mechanism is that the introduction of trace of nitrogen decreases the eutectoid point, that is, the transformation hardened region is enlarged under the same temperature distribution. Moreover, the layer treated by PNC+LQ process exhibits enhanced wear resistance, due to the lubrication effect and optimized impact toughness, which is contributed to the formation of oxide film consisting of low nitrogen compound (FeN0.076) and iron oxidation (mainly of Fe3O4).

  11. Temperature Dependence of Nitro-Quenching by Atmospheric-Pressure Plasma

    Science.gov (United States)

    Mitani, Masaki; Ichiki, Ryuta; Iwakiri, Yutaro; Akamine, Shuichi; Kanazawa, Seiji

    2015-09-01

    A lot of techniques exist as the hardening method of steels, such as nitriding, carburizing and quenching. However, low-alloy steels cannot be hardened by nitriding because hardening by nitriding requires nitride precipitates of special alloy elements such as rare metals. Recently, nitro-quenching (NQ) was developed as a new hardening process, where nitrogen invokes martensitic transformation instead of carbon. NQ is adaptable to hardening low-alloy steels because it does not require alloy elements. In industrial NQ, nitrogen diffusion into steel surface is operated in high temperature ammonia gas. As a new technology, we have developed surface hardening of low-alloy steel by NQ using an atmospheric-pressure plasma. Here the pulsed-arc plasma jet with nitrogen/hydrogen gas mixture is sprayed onto steel surface and then water quench the sample. As a result, the surface of low-alloy steel was partially hardened up to 800 Hv by producing iron-nitrogen martensite. However, the hardness profile is considerably non-uniform. We found that the non-uniform hardness profile can be controlled by changing the treatment gap, the gap between the jet nozzle and the sample surface. Eventually, we succeeded in hardening a targeted part of steel by optimizing the treatment gap. Moreover, we propose the mechanism of non-uniform hardness.

  12. Demonstrating Universal Scaling in Quench Dynamics of a Yukawa One-Component Plasma

    CERN Document Server

    Langin, T K; Maksimovic, N; McQuillen, P; Pohl, T; Vrinceanu, D; Killian, T C

    2015-01-01

    The Yukawa one-component plasma (OCP) is a paradigm model for describing plasmas that contain one component of interest and one or more other components that can be treated as a neutralizing, screening background. In appropriately scaled units, interactions are characterized entirely by a screening parameter, $\\kappa$. As a result, systems of similar $\\kappa$ show the same dynamics, regardless of the underlying parameters (e.g., density and temperature). We demonstrate this behavior using ultracold neutral plasmas (UNP) created by photoionizing a cold ($T\\le10$ mK) gas. The ions in UNP systems are well described by the Yukawa model, with the electrons providing the screening. Creation of the plasma through photoionization can be thought of as a rapid quench from $\\kappa_{0}=\\infty$ to a final $\\kappa$ value set by the electron density and temperature. We demonstrate experimentally that the post-quench dynamics are universal in $\\kappa$ over a factor of 30 in density and an order of magnitude in temperature. R...

  13. On drag forces and jet quenching in strongly-coupled plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Caceres, Elena [Facultad de Ciencias, Universidad de Colima, Bernal Diaz del Castillo 340, Colima, Colima (Mexico); Gueijosa, Alberto [Departamento de Fisica de Altas Energias, Instituto de Ciencias Nucleares, Universidad Autonoma de Mexico, Apdo. Postal 70-543, Mexico D.F.04510 (Mexico)

    2006-12-15

    We compute the drag force experienced by a heavy quark that moves through plasma in a gauge theory whose dual description involves arbitrary metric and dilaton fields. As a concrete application, we consider the cascading gauge theory at temperatures high above the deconfining scale, where we obtain a drag force with a non-trivial velocity dependence. We compare our results with the jet-quenching parameter for the same theory, and find qualitative agreement between the two approaches. Conversely, we calculate the jet-quenching parameter for N = 4 super-Yang-Mills with an R-charge density (or equivalently, a chemical potential), and compare our result with the corresponding drag force.

  14. Demonstrating universal scaling for dynamics of Yukawa one-component plasmas after an interaction quench

    Science.gov (United States)

    Langin, T. K.; Strickler, T.; Maksimovic, N.; McQuillen, P.; Pohl, T.; Vrinceanu, D.; Killian, T. C.

    2016-02-01

    The Yukawa one-component plasma (OCP) model is a paradigm for describing plasmas that contain one component of interest and one or more other components that can be treated as a neutralizing, screening background. In appropriately scaled units, interactions are characterized entirely by a screening parameter, κ . As a result, systems of similar κ show the same dynamics, regardless of the underlying parameters (e.g., density and temperature). We demonstrate this behavior using ultracold neutral plasmas (UNPs) created by photoionizing a cold (T ≤10 mK) gas. The ions in UNP systems are well described by the Yukawa model, with the electrons providing the screening. Creation of the plasma through photoionization can be thought of as a rapid quench of the interaction potential from κ =∞ to a final κ value set by the electron density and temperature. We demonstrate experimentally that the postquench dynamics are universal in κ over a factor of 30 in density and an order of magnitude in temperature. Results are compared with molecular-dynamics simulations. We also demonstrate that features of the postquench kinetic energy evolution, such as disorder-induced heating and kinetic-energy oscillations, can be used to determine the plasma density and the electron temperature.

  15. Quenching Plasma Waves in Two Dimensional Electron Gas by a Femtosecond Laser Pulse

    Science.gov (United States)

    Shur, Michael; Rudin, Sergey; Greg Rupper Collaboration; Andrey Muraviev Collaboration

    Plasmonic detectors of terahertz (THz) radiation using the plasma wave excitation in 2D electron gas are capable of detecting ultra short THz pulses. To study the plasma wave propagation and decay, we used femtosecond laser pulses to quench the plasma waves excited by a short THz pulse. The femtosecond laser pulse generates a large concentration of the electron-hole pairs effectively shorting the 2D electron gas channel and dramatically increasing the channel conductance. Immediately after the application of the femtosecond laser pulse, the equivalent circuit of the device reduces to the source and drain contact resistances connected by a short. The total response charge is equal to the integral of the current induced by the THz pulse from the moment of the THz pulse application to the moment of the femtosecond laser pulse application. This current is determined by the plasma wave rectification. Registering the charge as a function of the time delay between the THz and laser pulses allowed us to follow the plasmonic wave decay. We observed the decaying oscillations in a sample with a partially gated channel. The decay depends on the gate bias and reflects the interplay between the gated and ungated plasmons in the device channel. Army Research Office.

  16. Perturbative and nonperturbative aspects of jet quenching in near-critical quark-gluon plasmas

    Science.gov (United States)

    Xu, Jiechen

    In this thesis, we construct two QCD based energy loss models to perform quantitative analysis of jet quenching observables in ultra-relativistic nucleus-nucleus collisions at RHIC and the LHC. We first build up a perturbative QCD based CUJET2.0 jet flavor tomography model that couples the dynamical running coupling DGLV opacity series to bulk data constrained relativistic viscous hydrodynamic backgrounds. It solves the strong heavy quark energy loss puzzle at RHIC and explains the surprising transparency of the quark-gluon plasma (QGP) at the LHC. The observed azimuthal anisotropy of hard leading hadrons requires a path dependent jet-medium coupling in CUJET2.0 that implies physics of nonperturbative origin. To explore the nonperturbative chromo-electric and chromo-magnetic structure of the strongly-coupled QGP through jet probes, we build up a new CUJET3.0 framework that includes in CUJET2.0 both Polyakov loop suppressed semi-QGP chromo-electric charges and emergent chromo-magnetic monopoles in the critical transition regime. CUJET3.0 quantitatively describes the anisotropic hadron suppression at RHIC and the LHC. More significantly, it provides a robust connection between the long wavelength ``perfect fluidity'' of the QGP and the short distance jet transport in the QGP. This framework paves the way for ``measuring'' both perturbative and nonperturbative properties of the QGP, and more importantly for probing color confinement through jet quenching.

  17. O/S-1/ interactions - The product channels. [collisional electron quenching and chemical reaction pathway frequencies

    Science.gov (United States)

    Slanger, T. G.; Black, G.

    1978-01-01

    The first measurements are reported of the reaction pathways for the interaction between oxygen atoms in the 4.19 eV S-1 state, and four molecules, N2O, CO2, H2O, and NO. Distinction is made between three possible paths - quenching to O(D-1), quenching to O(P-3), and chemical reaction. With N2O, the most reasonable interpretation of the data indicates that there no reaction, in sharp contrast with the interaction between O(D-1) and N2O, which proceeds entirely by reaction. Similarly, there is no reaction with CO2. With H2O, the reactive pathway is the dominant one, although electronic quenching is not negligible. With NO, O(D-1) is the preferred product.

  18. Increased biomass productivity in green algae by tuning non-photochemical quenching

    Science.gov (United States)

    Berteotti, Silvia; Ballottari, Matteo; Bassi, Roberto

    2016-01-01

    Photosynthetic microalgae have a high potential for the production of biofuels and highly valued metabolites. However, their current industrial exploitation is limited by a productivity in photobioreactors that is low compared to potential productivity. The high cell density and pigment content of the surface layers of photosynthetic microalgae result in absorption of excess photons and energy dissipation through non-photochemical quenching (NPQ). NPQ prevents photoinhibition, but its activation reduces the efficiency of photosynthetic energy conversion. In Chlamydomonas reinhardtii, NPQ is catalyzed by protein subunits encoded by three lhcsr (light harvesting complex stress related) genes. Here, we show that heat dissipation and biomass productivity depends on LHCSR protein accumulation. Indeed, algal strains lacking two lhcsr genes can grow in a wide range of light growth conditions without suffering from photoinhibition and are more productive than wild-type. Thus, the down-regulation of NPQ appears to be a suitable strategy for improving light use efficiency for biomass and biofuel production in microalgae. PMID:26888481

  19. All Plasma Products Are Not Created Equal: Characterizing Differences Between Plasma Products

    Science.gov (United States)

    2015-06-01

    products that may affect efficacy and safety. METHODS: Four different plasma products were analyzed to include fresh frozen plasma (FFP), liquid plasma...have come onto the market. FFP, plasma frozen at 24 hours (PF-24), and liquid plasma (LP) are single-donor products pre- pared by separating plasma from...Transfusion. 2004;44(11):1674Y1675. 2. American Association of Blood Banks . Standards for Blood Banks and Transfusion Services. 26th ed. Bethesda, MD

  20. Gas Production with Coproduction of Methanol through Dry Quenching of Coke Developed by Yantai Tonqve Chemical/Yantai University

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Yantai Tongye Chemical Technology Co.,Ltd.and Yantai University have jointly studied and developed the proprietary technology for gas generation through dry quenching of coke with co-production of methanol.Currently this technology has been successfully licensed and the engineering and the design work is underway.

  1. The quenching effect of hydrogen on the nitrogen in metastable state in atmospheric-pressure N{sub 2}-H{sub 2} microwave plasma torch

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shou-Zhe, E-mail: lisz@dlut.edu.cn; Zhang, Xin; Chen, Chuan-Jie; Zhang, Jialiang [Key Laboratory of Materials Modification by Laser, Ion, Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China); School of Physics and Optoelectronic Technology, Dalian 116024 (China); Wang, Yong-Xing [College of Electrical Engineering, Dalian 116024 (China); Xia, Guang-Qing [School of Aeronautics and Astronautics, Dalian University of Technology, Dalian 116024 (China)

    2014-07-15

    The atmospheric-pressure microwave N{sub 2}-H{sub 2} plasma torch is generated and diagnosed by optical emission spectroscopy. It is found that a large amount of N atoms and NH radicals are generated in the plasma torch and the emission intensity of N{sub 2}{sup +} first negative band is the strongest over the spectra. The mixture of hydrogen in nitrogen plasma torch causes the morphology of the plasma discharge to change with appearance that the afterglow shrinks greatly and the emission intensity of N{sub 2}{sup +} first negative band decreases with more hydrogen mixed into nitrogen plasma. In atmospheric-pressure microwave-induced plasma torch, the hydrogen imposes a great influence on the characteristics of nitrogen plasma through the quenching effect of the hydrogen on the metastable state of N{sub 2}.

  2. 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.

  3. Jet quenching parameter of quark-gluon plasma in strong magnetic field: perturbative QCD and AdS/CFT correspondence

    CERN Document Server

    Li, Shiyong; Yee, Ho-Ung

    2016-01-01

    We compute the jet quenching parameter $\\hat q$ of QCD plasma in the presence of strong magnetic field in both weakly and strongly coupled regimes. In weakly coupled regime, we compute $\\hat q$ in perturbative QCD at complete leading order (that is, leading log as well as the constant under the log) in QCD coupling constant $\\alpha_s$, assuming the hierarchy of scales $\\alpha_s eB\\ll T^2\\ll eB$. We consider two cases of jet orientations with respect to the magnetic field: 1) the case of jet moving parallel to the magnetic field, 2) the case jet moving perpendicular to the magnetic field. In the former case, we find $\\hat q\\sim \\alpha_s^2 (eB)T\\log(1/\\alpha_s)$, while in the latter we have $\\hat q\\sim \\alpha_s^2 (eB)T\\log(T^2/\\alpha_seB)$. In both cases, this leading order result arises from the scatterings with thermally populated lowest Landau level quarks. In strongly coupled regime described by AdS/CFT correspondence, we find $\\hat q\\sim \\sqrt{\\lambda}(eB)T$ or $\\hat q\\sim\\sqrt{\\lambda}\\sqrt{eB}T^2$ in the...

  4. Near Zone Navier-Stokes Analysis of Heavy Quark Jet Quenching in an $\\mathcal{N}$ =4 SYM Plasma

    CERN Document Server

    Noronha, Jorge; Gyulassy, Miklos

    2007-01-01

    The near zone energy-momentum tensor of a supersonic heavy quark jet moving through a strongly-coupled $\\mathcal{N}=4$ SYM plasma is analyzed in terms of nonlinear Navier-Stokes hydrodynamics. We show that local isotropic equilibrium in the Landau frame holds to within 20% accuracy down to a length scale $\\sim 1/\\pi T$, much smaller than found previously from far zone analysis. For distances less than this scale, the AdS solution rapidly becomes non-isotropic and local equilibrium breaks down. The component of the dissipative stress also remain small compared to the advective (non-viscous) fluid stress down to distances $\\sim 1/\\pi T$ from the heavy quark jet. Our result, which is compatible with the thermalization timescales extracted from elliptic flow measurements, suggests that if AdS/CFT provides a good description of the RHIC system, the bulk of the quenched jet energy has more than enough time to locally thermalize and become encoded in the collective flow. The resulting flow pattern close to the quark...

  5. Generation of runaway electrons during the thermal quench in tokamaks

    Science.gov (United States)

    Aleynikov, Pavel; Breizman, Boris N.

    2017-04-01

    This work provides a systematic description of electron kinetics during impurity dominated thermal quenches. A Fokker–Planck equation for the hot electrons and a power balance equation for the bulk plasma are solved self-consistently, with impurity radiation as the dominant energy loss mechanism. We find that runaway production is facilitated by heavy injection of impurities up to prompt conversion of the total current into a sub-MeV runaway current. We also find that runaway formation is less efficient in plasmas with high pre-quench temperatures and predict significant radial variation of the runaway seed in such plasmas.

  6. Long-lived plasma and fast quenching of N2(C3Π u ) by electrons in the afterglow of a nanosecond capillary discharge in nitrogen

    Science.gov (United States)

    Lepikhin, N. D.; Klochko, A. V.; Popov, N. A.; Starikovskaia, S. M.

    2016-08-01

    Quenching of electronically excited nitrogen state, {{\\text{N}}2}≤ft({{\\text{C}}3}{{\\Pi}u},{{v}\\prime}=0\\right) , in the afterglow of nanosecond capillary discharge in pure nitrogen is studied. It is found experimentally that an additional collisional mechanism appears and dominates at high specific deposited energies leading to the anomalously fast quenching of the {{\\text{N}}2}≤ft({{\\text{C}}3}{{\\Pi}u}\\right) in the afterglow. On the basis of obtained experimental data and of the analysis of possible quenching agents, it is concluded that the anomalously fast deactivation of the {{\\text{N}}2}≤ft({{\\text{C}}3}{{\\Pi}u}\\right) can be explained by quenching by electrons. Long-lived plasma at time scale of hundreds nanoseconds after the end of the pulse is observed. High electron densities, about 1014 cm-3 at 27 mbar, are sustained by reactions of associative ionization. Kinetic 1D numerical modeling and comparison of calculated results with experimentally measured electric fields in the second high-voltage pulse 250 ns after the initial pulse, and electron density measurements in the afterglow confirm the validity of the suggested mechanism.

  7. Simulating plasma production from hypervelocity impacts

    Science.gov (United States)

    Fletcher, Alex; Close, Sigrid; Mathias, Donovan

    2015-09-01

    Hypervelocity particles, such as meteoroids and space debris, routinely impact spacecraft and are energetic enough to vaporize and ionize themselves and as well as a portion of the target material. The resulting plasma rapidly expands into the surrounding vacuum. While plasma measurements from hypervelocity impacts have been made using ground-based technologies such as light gas guns and Van de Graaff dust accelerators, some of the basic plasma properties vary significantly between experiments. There have been both ground-based and in-situ measurements of radio frequency (RF) emission from hypervelocity impacts, but the physical mechanism responsible and the possible connection to the impact-produced plasma are not well understood. Under certain conditions, the impact-produced plasma can have deleterious effects on spacecraft electronics by providing a new current path, triggering an electrostatic discharge, causing electromagnetic interference, or generating an electromagnetic pulse. Multi-physics simulations of plasma production from hypervelocity impacts are presented. These simulations incorporate elasticity and plasticity of the solid target, phase change and plasma formation, and non-ideal plasma physics due to the high density and low temperature of the plasma. A smoothed particle hydrodynamics method is used to perform a continuum dynamics simulation with these additional physics. By examining a series of hypervelocity impacts, basic properties of the impact produced plasma plume (density, temperature, expansion speed, charge state) are determined for impactor speeds between 10 and 72 km/s. For a large range of higher impact speeds (30-72 km/s), we find the temperature is unvarying at 2.5 eV. We also find that the plasma plume is weakly ionized for impact speeds less than 14 km/s and fully ionized for impact speeds greater than 20 km/s, independent of impactor mass. This is the same velocity threshold for the detection of RF emission in recent Van de Graaff

  8. Plasma processing methods for hydrogen production

    Science.gov (United States)

    Mizeraczyk, Jerzy; Jasiński, Mariusz

    2016-08-01

    In the future a transfer from the fossil fuel-based economy to hydrogen-based economy is expected. Therefore the development of systems for efficient H2 production becomes important. The several conventional methods of mass-scale (or central) H2 production (methane, natural gas and higher hydrocarbons reforming, coal gasification reforming) are well developed and their costs of H2 production are acceptable. However, due to the H2 transport and storage problems the small-scale (distributed) technologies for H2 production are demanded. However, these new technologies have to meet the requirement of producing H2 at a production cost of (1-2)/kg(H2) (or 60 g(H2)/kWh) by 2020 (the U.S. Department of Energy's target). Recently several plasma methods have been proposed for the small-scale H2 production. The most promising plasmas for this purpose seems to be those generated by gliding, plasmatron and nozzle arcs, and microwave discharges. In this paper plasma methods proposed for H2 production are briefly described and critically evaluated from the view point of H2 production efficiency. The paper is aiming at answering a question if any plasma method for the small-scale H2 production approaches such challenges as the production energy yield of 60 g(H2)/kWh, high production rate, high reliability and low investment cost. Contribution to the topical issue "6th Central European Symposium on Plasma Chemistry (CESPC-6)", edited by Nicolas Gherardi, Ester Marotta and Cristina Paradisi

  9. Microwave Plasma Production of Metal Nanopowders

    Directory of Open Access Journals (Sweden)

    Joseph Lik Hang Chau

    2014-06-01

    Full Text Available Metal and metal alloy nanopowders were prepared by using the microwave plasma synthesis method. The microwave plasma was operated in atmospheric pressure at a frequency of 2.45 GHz. The precursor decomposed thermally in the plasma reaction region and the products were then condensed in the heat exchanger, were separated from the gas by the powder filter, and then finally collected in the powder collector. The effect of various processing parameters such as plasma gas, carrier gas, cooling gas, precursor raw materials and feeding rate were studied in this work. Cu, Mo, W, Mo-Ni and Fe-Co nanopowders were successfully prepared by using the microwave plasma synthesis method. The processing conditions can be tuned to manipulate the particle size of the nanopowders.

  10. Nanofiltration of plasma-derived biopharmaceutical products.

    Science.gov (United States)

    Burnouf, T; Radosevich, M

    2003-01-01

    This review presents the current status on the use and benefits of viral removal filtration systems--known as nanofiltration--in the manufacture of plasma-derived coagulation factor concentrates and other biopharmaceutical products from human blood origin. Nanofiltration of plasma products has been implemented at a production scale in the early 1990s to improve margin of viral safety, as a complement to the viral reduction treatments, such as solvent-detergent and heat treatments, already applied for the inactivation of human immunodeficiency virus, hepatitis B and hepatitis C virus. The main reason for the introduction of nanofiltration was the need to improve product safety against non-enveloped viruses and to provide a possible safeguard against new infectious agents potentially entering the human plasma pool. Nanofiltration has gained quick acceptance as it is a relatively simple manufacturing step that consists in filtering protein solution through membranes of a very small pore size (typically 15-40 nm) under conditions that retain viruses by a mechanism largely based on size exclusion. Recent large-scale experience throughout the world has now established that nanofiltration is a robust and reliable viral reduction technique that can be applied to essentially all plasma products. Many of the licensed plasma products are currently nanofiltered. The technology has major advantages as it is flexible and it may combine efficient and largely predictable removal of more than 4 to 6 logs of a wide range of viruses, with an absence of denaturing effect on plasma proteins. Compared with other viral reduction means, nanofiltration may be the only method to date permitting efficient removal of enveloped and non-enveloped viruses under conditions where 90-95% of protein activity is recovered. New data indicate that nanofiltration may also remove prions, opening new perspectives in the development and interest of this technique. Nanofiltration is increasingly becoming a

  11. [Transfusion of plasma: products-indications].

    Science.gov (United States)

    Djoudi, R

    2013-05-01

    The use of therapeutic plasma has increased in France by more than 40% since 2002. This growth may be explained by the improvement in transfusion safety, the diminution of the risk of transmission of pathogens and the regained confidence of the physicians in blood products. Therapeutic plasma also benefits from additional procedures to reduce infectious (securisation) or immunological risks (selection of blood donors). Its application in massive transfusions has undergone a significant evolution over the last few years. A proactive attitude favouring early and important use of plasma on the basis of pre-established protocols is advocated henceforth. The prescription of therapeutic plasma for other indications must be guided by the results of biological tests and an evaluation of the haemorrhagic risk. Despite regular updating of the guidelines for good transfusion practice, plasma is still sometimes prescribed for prophylactic purposes in situations where the biological and/or clinical criteria do not justify it. Moreover, it is not recommended to use fresh frozen plasma in cases of deficiency of coagulation factors if the specific concentrates are available as intravenous fluids. Complementary clinical studies will be necessary to evaluate, in certain indications, the real benefits of the transfusion of plasma and the interest of replacing it by concentrates of coagulant factors (fibrinogen, prothrombin complex).

  12. Simulating plasma production from hypervelocity impacts

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, Alex, E-mail: alexcf@stanford.edu; Close, Sigrid [Stanford University, Aeronautics and Astronautics, 496 Lomita Mall, Stanford, California 94305 (United States); Mathias, Donovan [NASA Ames Research Center, Bldg. 258, Moffett Field, California 94035 (United States)

    2015-09-15

    Hypervelocity particles, such as meteoroids and space debris, routinely impact spacecraft and are energetic enough to vaporize and ionize themselves and as well as a portion of the target material. The resulting plasma rapidly expands into the surrounding vacuum. While plasma measurements from hypervelocity impacts have been made using ground-based technologies such as light gas guns and Van de Graaff dust accelerators, some of the basic plasma properties vary significantly between experiments. There have been both ground-based and in-situ measurements of radio frequency (RF) emission from hypervelocity impacts, but the physical mechanism responsible and the possible connection to the impact-produced plasma are not well understood. Under certain conditions, the impact-produced plasma can have deleterious effects on spacecraft electronics by providing a new current path, triggering an electrostatic discharge, causing electromagnetic interference, or generating an electromagnetic pulse. Multi-physics simulations of plasma production from hypervelocity impacts are presented. These simulations incorporate elasticity and plasticity of the solid target, phase change and plasma formation, and non-ideal plasma physics due to the high density and low temperature of the plasma. A smoothed particle hydrodynamics method is used to perform a continuum dynamics simulation with these additional physics. By examining a series of hypervelocity impacts, basic properties of the impact produced plasma plume (density, temperature, expansion speed, charge state) are determined for impactor speeds between 10 and 72 km/s. For a large range of higher impact speeds (30–72 km/s), we find the temperature is unvarying at 2.5 eV. We also find that the plasma plume is weakly ionized for impact speeds less than 14 km/s and fully ionized for impact speeds greater than 20 km/s, independent of impactor mass. This is the same velocity threshold for the detection of RF emission in recent

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

    Indian Academy of Sciences (India)

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

    2010-03-01

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

  14. On the difference between breakdown and quench voltages of argon plasma and its relation to $4p-4s$ atomic state transitions

    CERN Document Server

    Forati, Ebrahim; Sievenpiper, Dan

    2014-01-01

    Using a relaxation oscillator circuit, breakdown ($V_{\\mathrm{BD}}$) and quench ($V_{\\mathrm{Q}}$) voltages of a DC discharge microplasma between two needle probes are measured. High resolution modified Paschen curves are obtained for argon microplasmas including a quench voltage curve representing the voltage at which the plasma turns off. It is shown that, for a point to point microgap (e.g. the microgap between two needle probes) which describes many realistic microdevices, neither Paschen's law applies nor field emission is noticeable. Although normally $V_{\\mathrm{BD}}>V_{\\mathrm{Q}}$, it is observed that depending on environmental parameters of argon, such as pressure and the driving circuitry, plasma can exist in a different state with equal $V_{\\mathrm{BD}}$ and $V_{\\mathrm{Q}}$. Using emission line spectroscopy, it is shown that $V_{\\mathrm{BD}}$ and $V_{\\mathrm{Q}}$ are equal if the atomic excitation by the electric field dipole moment dominantly leads to one of the argon's metastable states ($4P_{5...

  15. On the difference between breakdown and quench voltages of argon plasma and its relation to 4p–4s atomic state transitions

    Energy Technology Data Exchange (ETDEWEB)

    Forati, Ebrahim, E-mail: forati@ieee.org; Piltan, Shiva; Sievenpiper, Dan, E-mail: dsievenpiper@ucsd.edu [University of California San Diego, La Jolla, California 92093 (United States)

    2015-02-02

    Using a relaxation oscillator circuit, breakdown (V{sub BD}) and quench (V{sub Q}) voltages of a DC discharge microplasma between two needle probes are measured. High resolution modified Paschen curves are obtained for argon microplasmas including a quench voltage curve representing the voltage at which the plasma turns off. It is shown that for a point to point microgap (e.g., the microgap between two needle probes) which describes many realistic microdevices, neither Paschen's law applies nor field emission is noticeable. Although normally V{sub BD} > V{sub Q,} it is observed that depending on environmental parameters of argon, such as pressure and the driving circuitry, plasma can exist in a different state with equal V{sub BD} and V{sub Q.} Using emission line spectroscopy, it is shown that V{sub BD} and V{sub Q} are equal if the atomic excitation by the electric field dipole moment dominantly leads to one of the argon's metastable states (4P{sub 5} in our study)

  16. Mechanism of the Quorum-Quenching Lactonase (AiiA) from Bacillus thuringiensis. 1. Product-Bound Structures

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dali; Momb, Jessica; Thomas, Pei W.; Moulin, Aaron; Petsko, Gregory A.; Fast, Walter; Ringe, Dagmar (Brandeis); (Texas)

    2008-08-06

    Enzymes capable of hydrolyzing N-acyl-l-homoserine lactones (AHLs) used in some bacterial quorum-sensing pathways are of considerable interest for their ability to block undesirable phenotypes. Most known AHL hydrolases that catalyze ring opening (AHL lactonases) are members of the metallo-{beta}-lactamase enzyme superfamily and rely on a dinuclear zinc site for catalysis and stability. Here we report the three-dimensional structures of three product complexes formed with the AHL lactonase from Bacillus thuringiensis. Structures of the lactonase bound with two different concentrations of the ring-opened product of N-hexanoyl-l-homoserine lactone are determined at 0.95 and 1.4 {angstrom} resolution and exhibit different product configurations. A structure of the ring-opened product of the non-natural N-hexanoyl-l-homocysteine thiolactone at 1.3 {angstrom} resolution is also determined. On the basis of these product-bound structures, a substrate-binding model is presented that differs from previous proposals. Additionally, the proximity of the product to active-site residues and observed changes in protein conformation and metal coordination provide insight into the catalytic mechanism of this quorum-quenching metalloenzyme.

  17. Hydrogen Production from Ammonia Using a Plasma Membrane Reactor

    Directory of Open Access Journals (Sweden)

    Shinji Kambara

    2016-06-01

    Full Text Available In this study, an efficient method for using pulsed plasma to produce hydrogen from ammonia was developed. An original pulsed plasma reactor with a hydrogen separation membrane was developed for efficient hydrogen production, and its hydrogen production performance was investigated. Hydrogen production in the plasma was affected by the applied voltage and flow rate of ammonia gas. The maximum hydrogen production flow rate of a typical plasma reactor was 8.7 L/h, whereas that of the plasma membrane reactor was 21.0 L/h. We found that ammonia recombination reactions in the plasma controlled hydrogen production in the plasma reactor. In the plasma membrane reactor, a significant increase in hydrogen production was obtained because ammonia recombination reactions were inhibited by the permeation of hydrogen radicals generated in the plasma through a palladium alloy membrane. The energy efficiency was 4.42 mol-H2/kWh depending on the discharge power.

  18. Reactive quenching of OH A 2Σ+ by O2 and CO: experimental and nonadiabatic theoretical studies of H- and O-atom product channels.

    Science.gov (United States)

    Lehman, Julia H; Lester, Marsha I; Yarkony, David R

    2012-09-07

    The outcomes following collisional quenching of electronically excited OH A (2)Σ(+) by O(2) and CO are examined in a combined experimental and theoretical study. The atomic products from reactive quenching are probed using two-photon laser-induced fluorescence to obtain H-atom Doppler profiles, O ((3)P(J)) atom fine structure distributions, and the relative yields of these products with H(2), O(2), and CO collision partners. The corresponding H-atom translational energy distributions are extracted for the H + O(3) and H + CO(2) product channels, in the latter case revealing that most of the available energy is funneled into internal excitation of CO(2). The experimental product branching ratios show that the O-atom producing pathways are the dominant outcomes of quenching: the OH A (2)Σ(+) + O(2) → O + HO(2) channel accounts for 48(3)% of products and the OH A (2)Σ(+) + CO → O + HCO channel yields 76(5)% of products. In addition, quenching of OH A (2)Σ(+) by O(2) generates H + O(3) products [12(3)%] and returns OH to its ground X (2)Π electronic state [40(1)%; L. P. Dempsey, T. D. Sechler, C. Murray, and M. I. Lester, J. Phys. Chem. A 113, 6851 (2009)]. Quenching of OH A (2)Σ(+) by CO also yields H + CO(2) reaction products [26(5)%]; however, OH X (2)Π (v" = 0,1) products from nonreactive quenching are not observed. Theoretical studies characterize the properties of energy minimized conical intersections in four regions of strong nonadiabatic coupling accessible from the OH A (2)Σ(+) + CO asymptote. Three of these regions have the O-side of OH pointing toward CO, which lead to atomic H and vibrationally excited CO(2) products and/or nonreactive quenching. In the fourth region, energy minimized points are located on a seam of conical intersection from the OH A (2)Σ(+) + CO asymptote to an energy minimized crossing with an extended OH bond length and the H-side of OH pointing toward CO in a bent configuration. This region, exoergic with respect to the

  19. The Sakaguchi reaction product quenches phycobilisome fluorescence, allowing determination of the arginine concentration in cells of Anabaena strain PCC 7120.

    Science.gov (United States)

    Ke, Shan; Haselkorn, Robert

    2013-01-01

    The filamentous cyanobacterium Anabaena fixes nitrogen in specialized cells called heterocysts. The immediate product of fixation, ammonia, is known to be assimilated by addition to glutamate to make glutamine. How fixed nitrogen is transported along the filament to the 10 to 20 vegetative cells that separate heterocysts is unknown. N-fixing heterocysts accumulate an insoluble polymer containing aspartate and arginine at the cell poles. Lockau's group has proposed that the polymer is degraded at the poles to provide a mobile carrier, arginine, to the vegetative cells (R. Richter, M. Hejazi, R. Kraft, K. Ziegler, and W. Lockau, Eur. J. Biochem. 263:163-169, 1999). We wished to use the Sakaguchi reaction for arginine to determine the relative cellular concentration of arginine along the filament. At present, the methods for measuring absorption of the Sakaguchi reaction product at 520 nm are insufficiently sensitive for that purpose. However, that product quenches the fluorescence of phycobiliproteins, which we have adapted to a determination of arginine. Our results are consistent with the proposal that arginine is a principal nitrogen carrier from heterocysts to vegetative cells in Anabaena.

  20. Dairy products and plasma cholesterol levels

    Directory of Open Access Journals (Sweden)

    Lena Ohlsson

    2010-08-01

    Full Text Available Cholesterol synthesized in the body or ingested is an essential lipid component for human survival from our earliest life. Newborns ingest about 3–4 times the amount per body weight through mother's milk compared to the dietary intake of adults. A birth level of 1.7 mmol/L plasma total cholesterol will increase to 4–4.5 mmol/L during the nursing period and continue to increase from adulthood around 40% throughout life. Coronary artery disease and other metabolic disorders are strongly associated with low-density lipoprotein (LDL and high-density lipoprotein (HDL cholesterol as well as triacylglycerol concentration. Milk fat contains a broad range of fatty acids and some have a negative impact on the cholesterol rich lipoproteins. The saturated fatty acids (SFAs, such as palmitic acid (C16:0, myristic acid (C14:0, and lauric acid (C12:0, increase total plasma cholesterol, especially LDL, and constitute 11.3 g/L of bovine milk, which is 44.8% of total fatty acid in milk fat. Replacement of dairy SFA and trans-fatty acids with polyunsaturated fatty acids decreases plasma cholesterol, especially LDL cholesterol, and is associated with a reduced risk of cardiovascular disease. Available data shows different effects on lipoproteins for different dairy products and there is uncertainty as to the impact a reasonable intake amount of dairy items has on cardiovascular risk. The aim of this review is to elucidate the effect of milk components and dairy products on total cholesterol, LDL, HDL, and the LDL/HDL quotients. Based on eight recent randomized controlled trials of parallel or cross-over design and recent reviews it can be concluded that replacement of saturated fat mainly (but not exclusively derived from high-fat dairy products with low-fat dairy products lowers LDL/HDL cholesterol and total/HDL cholesterol ratios. Whey, dairy fractions enriched in polar lipids, and techniques such as fermentation, or fortification of cows feeding can be used

  1. Production of coloured glass-ceramics from incinerator ash using thermal plasma technology.

    Science.gov (United States)

    Cheng, T W; Huang, M Z; Tzeng, C C; Cheng, K B; Ueng, T H

    2007-08-01

    Incineration is a major treatment process for municipal solid waste in Taiwan. It is estimated that over 1.5 Mt of incinerator ash are produced annually. This study proposes using thermal plasma technology to treat incinerator ash. Sintered glass-ceramics were produced using quenched vitrified slag with colouring agents added. The experimental results showed that the major crystalline phases developed in the sintered glass-ceramics were gehlenite and wollastonite, but many other secondary phases also appeared depending on the colouring agents added. The physical/mechanical properties, chemical resistance and toxicity characteristic leaching procedure of the coloured glass-ceramics were satisfactory. The glass-ceramic products obtained from incinerator ash treated with thermal plasma technology have great potential for building applications.

  2. Plasma and Plasma Protein Product Transfusion: A Canadian Blood Services Centre for Innovation Symposium.

    Science.gov (United States)

    Zeller, Michelle P; Al-Habsi, Khalid S; Golder, Mia; Walsh, Geraldine M; Sheffield, William P

    2015-07-01

    Plasma obtained via whole blood donation processing or via apheresis technology can either be transfused directly to patients or pooled and fractionated into plasma protein products that are concentrates of 1 or more purified plasma protein. The evidence base supporting clinical efficacy in most of the indications for which plasma is transfused is weak, whereas high-quality evidence supports the efficacy of plasma protein products in at least some of the clinical settings in which they are used. Transfusable plasma utilization remains composed in part of applications that fall outside of clinical practice guidelines. Plasma contains all of the soluble coagulation factors and is frequently transfused in efforts to restore or reinforce patient hemostasis. The biochemical complexities of coagulation have in recent years been rationalized in newer cell-based models that supplement the cascade hypothesis. Efforts to normalize widely used clinical hemostasis screening test values by plasma transfusion are thought to be misplaced, but superior rapid tests have been slow to emerge. The advent of non-vitamin K-dependent oral anticoagulants has brought new challenges to clinical laboratories in plasma testing and to clinicians needing to reverse non-vitamin K-dependent oral anticoagulants urgently. Current plasma-related controversies include prophylactic plasma transfusion before invasive procedures, plasma vs prothrombin complex concentrates for urgent warfarin reversal, and the utility of increased ratios of plasma to red blood cell units transfused in massive transfusion protocols. The first recombinant plasma protein products to reach the clinic were recombinant hemophilia treatment products, and these donor-free equivalents to factors VIII and IX are now being supplemented with novel products whose circulatory half-lives have been increased by chemical modification or genetic fusion. Achieving optimal plasma utilization is an ongoing challenge in the interconnected

  3. Plasma production for electron acceleration by resonant plasma wave

    Science.gov (United States)

    Anania, M. P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Croia, M.; Curcio, A.; Di Giovenale, D.; Di Pirro, G. P.; Filippi, F.; Ghigo, A.; Lollo, V.; Pella, S.; Pompili, R.; Romeo, S.; Ferrario, M.

    2016-09-01

    Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10-100 GV/m), enabling acceleration of electrons to GeV energy in few centimeter. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators (large energy spread, low repetition rate, and large emittance); radiofrequency-based accelerators, in fact, are limited in accelerating field (10-100 MV/m) requiring therefore hundred of meters of distances to reach the GeV energies, but can provide very bright electron bunches. To combine high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC_LAB (Ferrario et al., 2013 [1]). In particular here we focus on hydrogen plasma discharge, and in particular on the theoretical and numerical estimates of the ionization process which are very useful to design the discharge circuit and to evaluate the current needed to be supplied to the gas in order to have full ionization. Eventually, the current supplied to the gas simulated will be compared to that measured experimentally.

  4. Plasma production for electron acceleration by resonant plasma wave

    Energy Technology Data Exchange (ETDEWEB)

    Anania, M.P., E-mail: maria.pia.anania@lnf.infn.it [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Biagioni, A.; Chiadroni, E. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Cianchi, A. [University of Rome Tor Vergata - INFN, via della Ricerca Scientifica, 1, 00133 Roma (Italy); INFN, Via della Ricerca Scientifica, 1, 00133 Roma (Italy); Croia, M.; Curcio, A. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); University of Rome La Sapienza, Piazzale Aldo Moro, 2, 00185 Roma (Italy); Di Giovenale, D.; Di Pirro, G.P. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Filippi, F. [University of Rome La Sapienza, Piazzale Aldo Moro, 2, 00185 Roma (Italy); Ghigo, A.; Lollo, V.; Pella, S.; Pompili, R. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Romeo, S. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); University of Rome La Sapienza, Piazzale Aldo Moro, 2, 00185 Roma (Italy); Ferrario, M. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy)

    2016-09-01

    Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10–100 GV/m), enabling acceleration of electrons to GeV energy in few centimeter. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators (large energy spread, low repetition rate, and large emittance); radiofrequency-based accelerators, in fact, are limited in accelerating field (10–100 MV/m) requiring therefore hundred of meters of distances to reach the GeV energies, but can provide very bright electron bunches. To combine high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC-LAB (Ferrario et al., 2013 [1]). In particular here we focus on hydrogen plasma discharge, and in particular on the theoretical and numerical estimates of the ionization process which are very useful to design the discharge circuit and to evaluate the current needed to be supplied to the gas in order to have full ionization. Eventually, the current supplied to the gas simulated will be compared to that measured experimentally.

  5. Turbulent chromo-fields and thermal particle production in quark-gluon plasma medium

    CERN Document Server

    Chandra, Vinod

    2016-01-01

    The Weibel type instabilities appear in the expanding quark-gluon plasma (QGP) in relativistic heavy-ion collisions, due to the presence of momentum-space anisotropy, are responsible for the generation of the turbulent color fields. The ensemble averaged (ensemble of the turbulent fields) effective diffusive Vlasov equation, for the modified momentum distribution functions of the quarks and gluons encodes the physics of such instability and leads to the anomalous transport process in the QGP medium. In the present case, the solution of the linearized transport equation for the modified momentum distribution functions has been served as the modeling for the non-equilibrium momentum distribution functions for the QGP degrees of freedom. The strength of anisotropy has been related to a phenomenologically obtained jet-quenching parameter, $\\hat{q}$. We have computed the contribution of these anisotropic terms to the thermal dilepton production rates. The production rate has been seen to be appreciably sensitive t...

  6. Jet quenching and high-pt azimuthal asymmetry

    CERN Document Server

    Lokhtin, Igor P; Vitev, I

    2002-01-01

    The azimuthal anisotropy of high-pt particle production in non-central heavy ion collisions is among the most promising observables of partonic energy loss in an azimuthally non-symmetric volume of quark-gluon plasma. We discuss the implications of nuclear geometry for the models of partonic energy loss in the context of recent RHIC data and consequences for observation of jet quenching at the LHC.

  7. Weak Interaction Neutron Production Rates in Fully Ionized Plasmas

    CERN Document Server

    Widom, A; Srivastava, Y N

    2013-01-01

    Employing the weak interaction reaction wherein a heavy electron is captured by a proton to produce a neutron and a neutrino, the neutron production rate for neutral hydrogen gases and for fully ionized plasmas is computed. Using the Coulomb atomic bound state wave functions of a neutral hydrogen gas, our production rate results are in agreement with recent estimates by Maiani {\\it et al}. Using Coulomb scattering state wave functions for the fully ionized plasma, we find a substantially enhanced neutron production rate. The scattering wave function should replace the bound state wave function for estimates of the enhanced neutron production rate on water plasma drenched cathodes of chemical cells.

  8. Positron plasma control techniques for the production of cold antihydrogen

    Science.gov (United States)

    Funakoshi, R.; Amoretti, M.; Bonomi, G.; Bowe, P. D.; Canali, C.; Carraro, C.; Cesar, C. L.; Charlton, M.; Doser, M.; Fontana, A.; Fujiwara, M. C.; Genova, P.; Hangst, J. S.; Hayano, R. S.; Jørgensen, L. V.; Kellerbauer, A.; Lagomarsino, V.; Landua, R.; Lodi Rizzini, E.; Macrì, M.; Madsen, N.; Manuzio, G.; Mitchard, D.; Montagna, P.; Posada, L. G. C.; Rotondi, A.; Testera, G.; Variola, A.; Venturelli, L.; van der Werf, D. P.; Yamazaki, Y.; Zurlo, N.

    2007-07-01

    An observation of a clear dependence of antihydrogen production on positron plasma shapes is reported. For this purpose a plasma control method has been developed combining the plasma rotating-wall technique with a mode diagnostic system. With the help of real-time and nondestructive observations, the rotating-wall parameters have been optimized. The positron plasma can be manipulated into a wide range of shapes (aspect ratio 6.5⩽α≲80 ) and densities (1.5×108⩽n≲7×109cm-3) within a short duration (25s) compatible with the ATHENA antihydrogen production cycle.

  9. Positron plasma control techniques for the production of cold antihydrogen

    CERN Document Server

    Funakoshi, R; Bonomi, G; Bowe, P D; Canali, C; Carraro, C; Cesar, C L; Charlton, M; Doser, M; Fontana, A; Fujiwara, M C; Genova, P; Hangst, J S; Hayano, R S; Jørgensen, L V; Kellerbauer, A G; Lagomarsino, V; Landua, R; Lodi-Rizzini, E; Macrì, M; Madsen, N; Manuzio, G; Mitchard, D; Montagna, P; Posada, L G C; Rotondi, A; Testera, G; Variola, A; Venturelli, L; Van der Werf, D P; Yamazaki, Y; Zurlo, N

    2007-01-01

    An observation of a clear dependence of antihydrogen production on positron plasma shapes is reported. For this purpose a plasma control method has been developed combining the plasma rotating-wall technique with a mode diagnostic system. With the help of real-time and nondestructive observations, the rotating-wall parameters have been optimized. The positron plasma can be manipulated into a wide range of shapes (aspect ratio 6.5≤α≲80) and densities (1.5×108≤n≲7×109 cm−3) within a short duration (25 s) compatible with the ATHENA antihydrogen production cycle.

  10. Surface disorder production during plasma immersion implantation

    NARCIS (Netherlands)

    Lohner, T.; Khanh, N.Q.; Petrik, P.; Biro, L.P.; Fried, M.; Pinter, I.; Lehnert, W.; Frey, L.; Ryssel, H.; Wentink, D.J.; Gyulai, J.

    1998-01-01

    Comparative investigations were performed using high-depth-resolution Rutherford backscattering (RBS) combined with channeling, spectroellipsometry (SE) and atomic force microscopy (AFM) to analyze surface disorder and surface roughness formed during plasma immersion implantation of silicon (100) su

  11. Weak Interaction Neutron Production Rates in Fully Ionized Plasmas

    OpenAIRE

    Widom, A.; Swain, J.; Srivastava, Y. N.

    2013-01-01

    Employing the weak interaction reaction wherein a heavy electron is captured by a proton to produce a neutron and a neutrino, the neutron production rate for neutral hydrogen gases and for fully ionized plasmas is computed. Using the Coulomb atomic bound state wave functions of a neutral hydrogen gas, our production rate results are in agreement with recent estimates by Maiani {\\it et al}. Using Coulomb scattering state wave functions for the fully ionized plasma, we find a substantially enha...

  12. Plasma graviton production in TeV-scale gravity

    CERN Document Server

    Melkumova, E Yu

    2010-01-01

    We develop the theory of interaction of classical plasma with Kaluza-Klein (KK) gravitons in the ADD model of TeV-scale gravity. Plasma is described within the kinetic approach as the system of charged particles and Maxwell field both confined on the brane. Interaction with multidimensional gravity living in the bulk with $n$ compact extra dimensions is introduced within the linearized theory. The KK gravitons emission rates are computed taking into account plasma collective effects through the two-point correlation functions of the fluctuations of the plasma energy-momentum tensor. Apart from known mechanisms (such as bremsstrahlung and gravi-Primakoff effect) we find essentially collective channels such as the coalescence of plasma waves into gravitons which may be manifest in turbulent plasmas. Our results indicate that commonly used rates of the KK gravitons production in stars and supernovae may be underestimated.

  13. Determination of berberine and the study of fluorescence quenching mechanism between berberine and enzyme-catalyzed product

    Science.gov (United States)

    Wang, Huaiyou; Zhang, Miao; Lv, Qingluan; Yue, Ningning; Gong, Bin

    2009-08-01

    A new method for determining berberine has been established based on the principle of fluorescence quenching. The calibration curve was found to be linear between F0/ F and the concentration of berberine with the range of 3.00-20.0 μg mL -1. The detection limit was 0.51 μg mL -1 and the relative standard derivative was 0.18%. Effects of pH, foreign ions and the optimization of variables on the determination of berberine have been examined. The mechanism of the fluorescence quenching has been discussed. The binding constant and the number of binding sites were 1.70 × 10 6 L mol -1 and 1.14, respectively. The data, Δ H = 42.71 kJ mol -1, Δ S = 264.3 J K -1 mol -1 and the mean value Δ G = -39.65 kJ mol -1 were estimated which showed that the reaction was spontaneous and endothermic. The main binding force was hydrophobic force because both Δ H and Δ S were positive.

  14. High density plasma production in a multicusp plasma generator with RF antenna

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yasuo; Hanada, Masaya; Okumura, Yoshikazu; Tanaka, Masanobu [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1992-10-01

    A high density plasma was produced by radio-frequency in a multicusp plasma generator. The generator is a cylindrical chamber of 200 mm in inner diameter and 270 mm in length with 1-3 turn copper tube antenna. By injecting a 2 MHz, 20 kW RF into the multicusp plasma generator, hydrogen plasma of an ion saturation current density of 120 mA/cm{sup 2} and a hydrogen plasma of a density of 6.0 x 10{sup 11} cm{sup -3} was produced at a pressure of 0.6 Pa in the generator. The ion saturation current density was uniform over the central area of 100 mm in diameter. Coating the antenna with an insulator, we proved that the efficiency of the plasma production was improved. (author).

  15. High density plasma production in a multicusp plasma generator with RF antenna

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yasuo; Hanada, Masaya; Okumura, Yoshikazu; Tanaka, Masanobu (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment)

    1992-10-01

    A high density plasma was produced by radio-frequency in a multicusp plasma generator. The generator is a cylindrical chamber of 200 mm in inner diameter and 270 mm in length with 1-3 turn copper tube antenna. By injecting a 2 MHz, 20 kW RF into the multicusp plasma generator, hydrogen plasma of an ion saturation current density of 120 mA/cm[sup 2] and a hydrogen plasma of a density of 6.0 x 10[sup 11] cm[sup -3] was produced at a pressure of 0.6 Pa in the generator. The ion saturation current density was uniform over the central area of 100 mm in diameter. Coating the antenna with an insulator, we proved that the efficiency of the plasma production was improved. (author).

  16. 40 CFR 1065.675 - CLD quench verification calculations.

    Science.gov (United States)

    2010-07-01

    ... verification calculations. Perform CLD quench-check calculations as follows: (a) Perform a CLD analyzer quench... water content in combustion air, fuel combustion products, and dilution air (if applicable). If you... the maximum expected CO2 content in fuel combustion products and dilution air. (d) Calculate quench...

  17. Condensation production in comet tail plasma

    Directory of Open Access Journals (Sweden)

    S. V. Koshevaya

    2000-01-01

    Full Text Available Los solitones producen condensaciones en la cola del cometa, como resultado de su interacci on con el viento solar. Se obtienen las condiciones de excitaci on de las ondas ion ac usticas y polvo-ac usticas. La teor a presentada, trata sobre los solitones ion-ac usticos polvosos en este plasma magnetizado. Se demuestra que la longitud de Debye y el radio de cyclotr on de las part culas de polvo cargadas, de nen la dimensi on transversal de los solitones polvo-ac usticos. Para valores t picos de los par ametros, las dimensiones estimadas de los solitones son de varios Km, lo cual concuerda con los datos obtenidos de las observaciones.

  18. Plasma electrolytic treatment of products after selective laser melting

    Science.gov (United States)

    Kashapov, L. N.; Kashapov, N. F.; Kashapov, R. N.; Denisov, D. G.

    2016-01-01

    The aim of the work was to study the possibilities of plasma electrolytic treatment for cleaning surfaces of metal products obtained by the SLM-technology. We found that the most effective cleaning from the large alloy particles occurs in the "hydrodynamic" mode, when the occurrence of hydrodynamic pulses observed. Further smoothing of irregularities eliminated by a stable burning of discharge in vapor shell. Analysis the morphology of the surface of difficult specialized products, such as crown conical gears, after plasma hydrodynamic treatment showed efficiency and advantages in comparison to conventional methods of final cleaning such as shot blasting.

  19. Studies on plasma production in a large volume system using multiple compact ECR plasma sources

    Science.gov (United States)

    Tarey, R. D.; Ganguli, A.; Sahu, D.; Narayanan, R.; Arora, N.

    2017-01-01

    This paper presents a scheme for large volume plasma production using multiple highly portable compact ECR plasma sources (CEPS) (Ganguli et al 2016 Plasma Source Sci. Technol. 25 025026). The large volume plasma system (LVPS) described in the paper is a scalable, cylindrical vessel of diameter  ≈1 m, consisting of source and spacer sections with multiple CEPS mounted symmetrically on the periphery of the source sections. Scaling is achieved by altering the number of source sections/the number of sources in a source section or changing the number of spacer sections for adjusting the spacing between the source sections. A series of plasma characterization experiments using argon gas were conducted on the LVPS under different configurations of CEPS, source and spacer sections, for an operating pressure in the range 0.5-20 mTorr, and a microwave power level in the range 400-500 W per source. Using Langmuir probes (LP), it was possible to show that the plasma density (~1  -  2  ×  1011 cm-3) remains fairly uniform inside the system and decreases marginally close to the chamber wall, and this uniformity increases with an increase in the number of sources. It was seen that a warm electron population (60-80 eV) is always present and is about 0.1% of the bulk plasma density. The mechanism of plasma production is discussed in light of the results obtained for a single CEPS (Ganguli et al 2016 Plasma Source Sci. Technol. 25 025026).

  20. Hydroxyl radical production in plasma electrolysis with KOH electrolyte solution

    Energy Technology Data Exchange (ETDEWEB)

    Saksono, Nelson; Febiyanti, Irine Ayu, E-mail: irine.ayu41@ui.ac.id; Utami, Nissa; Ibrahim [Department of Chemical Engineering, Universitas Indonesia, Depok 16424, Indonesia Phone: +62217863516, Fax: +62217863515 (Indonesia)

    2015-12-29

    Plasma electrolysis is an effective technology for producing hydroxyl radical (•OH). This method can be used for waste degradation process. This study was conducted to obtain the influence of applied voltage, electrolyte concentration, and anode depth in the plasma electrolysis system for producing hydroxyl radical. The materials of anode and cathode, respectively, were made from tungsten and stainless steel. KOH solution was used as the solution. Determination of hydroxyl radical production was done by measuring H{sub 2}O{sub 2} amount formed in plasma system using an iodometric titration method, while the electrical energy consumed was obtained by measuring the electrical current throughout the process. The highest hydroxyl radical production was 3.51 mmol reached with 237 kJ energy consumption in the power supply voltage 600 V, 0.02 M KOH, and 0.5 cm depth of anode.

  1. Reactive quenching of OH A {sup 2}{Sigma}{sup +} by O{sub 2} and CO: Experimental and nonadiabatic theoretical studies of H- and O-atom product channels

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, Julia H.; Lester, Marsha I. [Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323 (United States); Yarkony, David R. [Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218 (United States)

    2012-09-07

    The outcomes following collisional quenching of electronically excited OH A {sup 2}{Sigma}{sup +} by O{sub 2} and CO are examined in a combined experimental and theoretical study. The atomic products from reactive quenching are probed using two-photon laser-induced fluorescence to obtain H-atom Doppler profiles, O ({sup 3}P{sub J}) atom fine structure distributions, and the relative yields of these products with H{sub 2}, O{sub 2}, and CO collision partners. The corresponding H-atom translational energy distributions are extracted for the H + O{sub 3} and H + CO{sub 2} product channels, in the latter case revealing that most of the available energy is funneled into internal excitation of CO{sub 2}. The experimental product branching ratios show that the O-atom producing pathways are the dominant outcomes of quenching: the OH A {sup 2}{Sigma}{sup +}+ O{sub 2}{yields} O + HO{sub 2} channel accounts for 48(3)% of products and the OH A {sup 2}{Sigma}{sup +}+ CO {yields} O + HCO channel yields 76(5)% of products. In addition, quenching of OH A {sup 2}{Sigma}{sup +} by O{sub 2} generates H + O{sub 3} products [12(3)%] and returns OH to its ground X {sup 2}{Pi} electronic state [40(1)%; L. P. Dempsey, T. D. Sechler, C. Murray, and M. I. Lester, J. Phys. Chem. A 113, 6851 (2009)]. Quenching of OH A {sup 2}{Sigma}{sup +} by CO also yields H + CO{sub 2} reaction products [26(5)%]; however, OH X {sup 2}{Pi} (v{sup Double-Prime }= 0,1) products from nonreactive quenching are not observed. Theoretical studies characterize the properties of energy minimized conical intersections in four regions of strong nonadiabatic coupling accessible from the OH A {sup 2}{Sigma}{sup +}+ CO asymptote. Three of these regions have the O-side of OH pointing toward CO, which lead to atomic H and vibrationally excited CO{sub 2} products and/or nonreactive quenching. In the fourth region, energy minimized points are located on a seam of conical intersection from the OH A {sup 2}{Sigma}{sup +}+ CO

  2. Plasma metallurgical production of nanocrystalline borides and carbides

    Science.gov (United States)

    Galevsky, G. V.; Rudneva, V. V.; Cherepanov, A. N.; Galevsky, S. G.; Efimova, K. A.

    2016-09-01

    he experience in production and study of properties of nanocrystalline borides and chromium carbides, titanium, silicon was summarized. The design and features of the vertical three-jet once-through reactor with power 150 kW, used in the plasma metallurgical production, was described. The technological, thermotechnical and resource characteristics of the reactor were identified. The parameters of borides and carbides synthesis, their main characteristics in the nanodispersed state and equipment-technological scheme of production were provided. Evaluation of engineering-and-economical performance of the laboratory and industrial levels of borides and carbides production and the state corresponding to the segment of the world market was carried out.

  3. Plasma-Assisted Pretreatment of Wheat Straw for Ethanol Production

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Kádár, Zsófia; Thomsen, Anne Belinda

    2011-01-01

    The potential of wheat straw for ethanol production after pretreatment with O3 generated in a plasma at atmospheric pressure and room temperature followed by fermentation was investigated. We found that cellulose and hemicellulose remained unaltered after ozonisation and a subsequent washing step...

  4. A rapid quenched-flow device for the characterisation of the nascent polymerisation of ethylene under industrial conditions

    NARCIS (Netherlands)

    Di Martino, A.; Di Martino, Audrey; Broyer, Jean Pierre; Spitz, Roger; Weickert, G.; McKenna, Timothy F.

    2005-01-01

    A quenched-flow reactor is introduced as an effective means for the production of polyolefin particles with precisely controlled reaction times as low as 40 ms. The use of off-line scanning electron microscopy and induced-coupled plasma yields experimental data on the development of the kinetics and

  5. A Rapid Quenched-Flow Device for the Characterisation of the Nascent Polymerisation of Ethylene under Industrial Conditions

    NARCIS (Netherlands)

    Di Martino, Audrey; Broyer, Jean Pierre; Spitz, Roger; Weickert, Günter; McKenna, Timothy F.

    2005-01-01

    A quenched-flow reactor is introduced as an effective means for the production of polyolefin particles with precisely controlled reaction times as low as 40 ms. The use of off-line scanning electron microscopy and induced-coupled plasma yields experimental data on the development of the kinetics and

  6. Scalable graphene production: perspectives and challenges of plasma applications

    Science.gov (United States)

    Levchenko, Igor; Ostrikov, Kostya (Ken); Zheng, Jie; Li, Xingguo; Keidar, Michael; B. K. Teo, Kenneth

    2016-05-01

    Graphene, a newly discovered and extensively investigated material, has many unique and extraordinary properties which promise major technological advances in fields ranging from electronics to mechanical engineering and food production. Unfortunately, complex techniques and high production costs hinder commonplace applications. Scaling of existing graphene production techniques to the industrial level without compromising its properties is a current challenge. This article focuses on the perspectives and challenges of scalability, equipment, and technological perspectives of the plasma-based techniques which offer many unique possibilities for the synthesis of graphene and graphene-containing products. The plasma-based processes are amenable for scaling and could also be useful to enhance the controllability of the conventional chemical vapour deposition method and some other techniques, and to ensure a good quality of the produced graphene. We examine the unique features of the plasma-enhanced graphene production approaches, including the techniques based on inductively-coupled and arc discharges, in the context of their potential scaling to mass production following the generic scaling approaches applicable to the existing processes and systems. This work analyses a large amount of the recent literature on graphene production by various techniques and summarizes the results in a tabular form to provide a simple and convenient comparison of several available techniques. Our analysis reveals a significant potential of scalability for plasma-based technologies, based on the scaling-related process characteristics. Among other processes, a greater yield of 1 g × h-1 m-2 was reached for the arc discharge technology, whereas the other plasma-based techniques show process yields comparable to the neutral-gas based methods. Selected plasma-based techniques show lower energy consumption than in thermal CVD processes, and the ability to produce graphene flakes of various

  7. Finite Element Simulation of Metal Quenching

    Institute of Scientific and Technical Information of China (English)

    方刚; 曾攀

    2004-01-01

    The evolution of the phase transformation and the resulting internal stresses and strains in metallic parts during quenching were modeled numerically. The numerical simulation of the metal quenching process was based on the metallo-thermo-mechanical theory using the finite element method to couple the temperature, phase transformation, and stress-strain fields. The numerical models are presented for the heat treatment and kinetics of the phase transformation. The finite element models and the phase transition kinetics accurately predict the distribution of the microstructure volume fractions, the temperature, the distortion, and the stress-strain relation during quenching. The two examples used to validate the models are the quenching of a small gear and of a large turbine rotor. The simulation results for the martensite phase volume fraction, the stresses, and the distortion in the gear agree well with the experimental data. The models can be used to optimize the quenching conditions to ensure product quality.

  8. 钢板压力淬火生产线控制系统%Control System of Armor Plate Press Quenching Production Line

    Institute of Scientific and Technical Information of China (English)

    王以琦; 施建华; 彭光宇; 王克伟; 马丹; 李超

    2012-01-01

    A set of control system was developed, which realized all kinds of precise control to press quenching produc-tion line, and met the requirement s of process of a variety of production. The production line requires high precise control, and the temperature levelling of furnace can reach between -10℃ and +10℃ , it is rarely seen in domestic heat treatment furnace. Moreover, it has the characteristics such as automation, high producing efficiency, low energy costs, good operat-ing environment, low intensity of labour and so on, the level of technology are advanced compared with other congeneric production lines in domestic. After large -scale production, the results showed that all kinds of production showed high quality.%开发了一套控制系统,实现了对压力淬火生产线的各种精确控制,满足了多品种工艺生产要求.该控制系统控制精度高,可保证生产线中燃气辊底炉炉温均匀性达到±10℃以内.经实践验证,该生产线生产效率高,能耗小,操作环境好,劳动强度低,技术水平在国内同类生产线中居领先地位.规模生产结果表明,各品种规格的产品均满足质量要求.

  9. Holographic study on the jet quenching parameter in anisotropic systems

    CERN Document Server

    Wang, Luying

    2016-01-01

    We first calculate the jet quenching parameter of an anisotropic plasma with a U(1) chemical potential via the AdS/CFT duality. The effects of charge, anisotropy parameter and quark motion direction on the jet quenching parameter are investigated. We then discuss the situation of anisotropic black brane in the IR region. We study both the jet quenching parameters along the longitudinal direction and transverse plane.

  10. Holographic study of the jet quenching parameter in anisotropic systems

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Luying [Shanghai University, Department of Physics, Shanghai (China); Wu, Shang-Yu [National Chiao Tung University, Department of Electrophysics, Hsinchu (China)

    2016-11-15

    We first calculate the jet quenching parameter of an anisotropic plasma with a U(1) chemical potential via AdS/CFT duality. The effects of charge, anisotropy parameter, and quark motion direction on the jet quenching parameter are investigated. We then discuss the situation of an anisotropic black brane in the IR region. We study both the jet quenching parameters along the longitudinal direction and the transverse plane. (orig.)

  11. ELECTROLYTIC-PLASMA TREATMENT OF INNER SURFACE OF TUBULAR PRODUCTS

    Directory of Open Access Journals (Sweden)

    Yu. G. Alekseev

    2016-01-01

    Full Text Available While manufacturing a number of important tubular products stringent requirements have been imposed on quality of their inner surfaces. The well-known methods for inner surface treatment of pipes include sandblasting, chemical cleaning with acid reagents (oxalic, formic, sulfamic, orthophosphoric acids and electrochemical polishing. Disadvantages of the chemical method are cleaning-up irregularities, high metal removal, limited number of reagent application, complicated selection of reagent chemical composition and concentration, complicated and environmentally harmful recycling of waste chemicals, high cost of reagents. Low productivity at a high cost, as well as hazardous impact on personnel due to high dispersion of abrasive dust are considered as disadvantages of sandblasting. Electrochemical polishing is characterized by the following disadvantages: low processing productivity because supply of high currents is rather difficult due to electrolyte scattering capacity away from the main electrode action zone, limited length of the cavity to be treated due to heating of flexible current leads at operating current densities, application of expensive aggressive electrolytes and high costs of their recycling. A new method for polishing and cleaning of inner surfaces of tubular products based on electrolyte-plasma treatment has been developed. In comparison with the existing methods the proposed methods ensures quality processing with high intensity while applying non-toxic, environmentally friendly and cheap electrolytes. The paper presents results of investigations on technological specific features of electrolyte-plasma treatment for inner surfaces of tubular products: influence of slotted nozzle width, electrolyte flow and rate on stability of gas-vapor blanket, current density and productivity. Results of the research have made it possible to determine modes that provide stability and high productivity in the process of electrolyte-plasma

  12. Sustainability of a public system for plasma collection, contract fractionation and plasma-derived medicinal product manufacturing.

    Science.gov (United States)

    Grazzini, Giuliano; Ceccarelli, Anna; Calteri, Deanna; Catalano, Liviana; Calizzani, Gabriele; Cicchetti, Americo

    2013-09-01

    In Italy, the financial reimbursement for labile blood components exchanged between Regions is regulated by national tariffs defined in 1991 and updated in 1993-2003. Over the last five years, the need for establishing standard costs of healthcare services has arisen critically. In this perspective, the present study is aimed at defining both the costs of production of blood components and the related prices, as well as the prices of plasma-derived medicinal products obtained by national plasma, to be used for interregional financial reimbursement. In order to analyse the costs of production of blood components, 12 out 318 blood establishments were selected in 8 Italian Regions. For each step of the production process, driving costs were identified and production costs were. To define the costs of plasma-derived medicinal products obtained by national plasma, industrial costs currently sustained by National Health Service for contract fractionation were taken into account. The production costs of plasma-derived medicinal products obtained from national plasma showed a huge variability among blood establishments, which was much lower after standardization. The new suggested plasma tariffs were quite similar to those currently in force. Comparing the overall costs theoretically sustained by the National Health Service for plasma-derived medicinal products obtained from national plasma to current commercial costs, demonstrates that the national blood system could gain a 10% cost saving if it were able to produce plasma for fractionation within the standard costs defined in this study. Achieving national self-sufficiency through the production of plasma-derived medicinal products from national plasma, is a strategic goal of the National Health Service which must comply not only with quality, safety and availability requirements but also with the increasingly pressing need for economic sustainability.

  13. Understanding neutron production in the deuterium dense plasma focus

    Energy Technology Data Exchange (ETDEWEB)

    Appelbe, Brian, E-mail: b.appelbe07@imperial.ac.uk, E-mail: j.chittenden@imperial.ac.uk; Chittenden, Jeremy, E-mail: b.appelbe07@imperial.ac.uk, E-mail: j.chittenden@imperial.ac.uk [The Blackett Laboratory, Imperial College London, SW7 2AZ (United Kingdom)

    2014-12-15

    The deuterium Dense Plasma Focus (DPF) can produce copious amounts of MeV neutrons and can be used as an efficient neutron source. However, the mechanism by which neutrons are produced within the DPF is poorly understood and this limits our ability to optimize the device. In this paper we present results from a computational study aimed at understanding how neutron production occurs in DPFs with a current between 70 kA and 500 kA and which parameters can affect it. A combination of MHD and kinetic tools are used to model the different stages of the DPF implosion. It is shown that the anode shape can significantly affect the structure of the imploding plasma and that instabilities in the implosion lead to the generation of large electric fields at stagnation. These electric fields can accelerate deuterium ions within the stagnating plasma to large (>100 keV) energies leading to reactions with ions in the cold dense plasma. It is shown that the electromagnetic fields present can significantly affect the trajectories of the accelerated ions and the resulting neutron production.

  14. Modeling production of e+/--pair plasma in AGNs

    Science.gov (United States)

    Ford, Alex; Medvedev, Mikhail V.

    2016-10-01

    Processes around spinning supermassive black holes in active galactic nuclei (AGN) are believed to determine how relativistic jets are launched and how the black hole energy is extracted. The key question in these processes is the origin of plasma in black hole magnetospheres. The only reasonable mechanism is believed to be the electron-position cascade - the multistage process involving seed photons from an accretion disk, which are Compton up-scattered by charges accelerated in a gap region of a force-free magnetosphere with subsequent photon-photon pair production. In order to explore the process of the e+/- plasma production, we developed a numerical code which models the dynamics of the cascade along magnetic field lines. We demonstrate that plasma production is sensitive to the spectrum of the ambient photon and magnetic fields, the black hole mass and spin, and other parameters. We discuss the results and observational predictions. Supported by KU CLAS and DOE Grant ID0000225143 (07/01/16).

  15. Entropy production and inward heat pinch of plasma

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Kimitaka [National Inst. for Fusion Science, Nagoya (Japan); Itoh, Sanae

    1996-02-01

    Heat pinch phenomena in the plasma with peripheral heating is discussed from the view point of thermodynamics. The entropy production rate associated with inward energy flow in the presence of energy exchange between electrons and ions is calculated. The inward energy flow can increase the total entropy production rate. It is conjectured that the outward energy flow of colder species (say ions) could sustain the energy flux of hotter species (say electrons) in the core, which flows into the direction of higher temperature. (author)

  16. Unusual long-chain N-acyl homoserine lactone production by and presence of quorum quenching activity in bacterial isolates from diseased tilapia fish.

    Directory of Open Access Journals (Sweden)

    Chien-Yi Chang

    Full Text Available Growth-dependent cell-cell communication termed quorum sensing is a key regulatory system in bacteria for controlling gene expression including virulence factors. In this study five potential bacterial pathogens including Bacillus sp. W2.2, Klebsiella sp. W4.2, Pseudomonas sp. W3 and W3.1 and Serratia sp. W2.3 were isolated from diseased Tilapia fish in Malaysia, supplied by the leading global fish supplier. Proteolytic activity assays confirmed that with the exception of Klebsiella sp. W4.2, all isolates showed distinct proteolytic activity. Furthermore Bacillus sp. W2.2 and Pseudomonas sp. strains W3 and W3.1 also displayed haemolytic activity. By using high resolution liquid chromatography mass spectrometry, we revealed the presence of unusually long-chain N-(3-oxohexadecanoyl-homoserine lactone (3-oxo-C16-HSL from Pseudomonas sp. W3.1 and N-dodecanoyl-homoserine lactone (C12-HSL from Serratia sp. W2.3, respectively. Interestingly, Pseudomonas sp. W3.1 also produced a wide range of Pseudomonas quinolone signalling (PQS molecules. Pseudomonas sp. W3 did not show any quorum sensing properties but possessed quorum quenching activity that inactivated AHLs. This study is the first documentation that shows unusual long-chain AHLs production in Serratia sp. and Pseudomonas sp. isolated from diseased fish and the latter also produce a wide range of PQS molecules.

  17. Investigating jet quenching on the lattice

    CERN Document Server

    Panero, Marco; Schäfer, Andreas

    2014-01-01

    Due to the dynamical, real-time, nature of the phenomenon, the study of jet quenching via lattice QCD simulations is not straightforward. In this contribution, however, we show how one can extract information about the momentum broadening of a hard parton moving in the quark-gluon plasma, from lattice calculations. After discussing the basic idea (originally proposed by Caron-Huot), we present a recent study, in which we estimated the jet quenching parameter non-perturbatively, from the lattice evaluation of a particular set of gauge-invariant operators.

  18. Hydrogen production from dimethyl ether using corona discharge plasma

    Science.gov (United States)

    Zou, Ji-Jun; Zhang, Yue-Ping; Liu, Chang-Jun

    Dimethyl ether (DME), with its non-toxic character, high H/C ratio and high-energy volumetric density, is an ideal resource for hydrogen production. In this work, hydrogen production from the decomposition of DME using corona discharge has been studied. The corona discharge plasma decomposition was conducted at ambient conditions. The effects of dilution gas (argon), flow rate, frequency and waveforms on the DME decomposition were investigated. The addition of dilution gas can significantly increase the hydrogen production rate. The highest hydrogen production rate with the lowest energy consumption presents at the flow rate of 27.5 Nml min -1. AC voltage is more favored than DC voltage for the production of hydrogen with less energy input. The optimal frequency is 2.0 kHz. The hydrogen production rate is also affected by the input waveform and decreases as following: sinusoid triangular > sinusoid > ramp > square, whereas the sinusoid waveform shows the highest energy efficiency. The corona discharge decomposition of DME is leading to a simple, easy and convenient hydrogen production with no needs of catalyst and external heating.

  19. Electronic quenching of OH(A) by water in atmospheric pressure plasmas and its influence on the gas temperature determination by OH(A-X) emission

    Energy Technology Data Exchange (ETDEWEB)

    Bruggeman, Peter; Schram, Daan C [Department of Applied Physics, Technische Universiteit Eindhoven, PO Box 513, 5600 MB Eindhoven (Netherlands); Iza, Felipe; Kong, Michael G [Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom); Guns, Peter; Lauwers, Daniel; Leys, Christophe [Department of Applied Physics, Ghent University, Jozef Plateaustraat 22, B-9000 Ghent (Belgium); Gonzalvo, Yolanda Aranda [Plasma and Surface Analysis Division, Hiden Analytical Ltd, 420 Europa Boulevard, Warrington WA5 7UN (United Kingdom)], E-mail: p.j.bruggeman@tue.nl

    2010-02-15

    In this paper it is shown that electronic quenching of OH(A) by water prevents thermalization of the rotational population distribution of OH(A). This means that the observed ro-vibrational OH(A-X) emission band is (at least partially) an image of the formation process and is determined not only by the gas temperature. The formation of negative ions and clusters for larger water concentrations can contribute to the non-equilibrium. The above is demonstrated in RF excited atmospheric pressure glow discharges in He-water mixtures in a parallel metal plate reactor by optical emission spectroscopy. For this particular case a significant overpopulation of high rotational states appears around 1000 ppm H{sub 2}O in He. The smallest temperature parameter of a non-Boltzmann (two-temperature) distribution fitted to the experimental spectrum of OH(A-X) gives a good representation of the gas temperature. Only the rotational states with the smallest rotational numbers (J {<=} 7) are thermalized and representative for the gas temperature.

  20. Microgravity Production of Nanoparticles of Novel Materials Using Plasma Synthesis

    Science.gov (United States)

    Frenklach, Michael; Fernandez-Pello, Carlos

    2001-01-01

    The research goal is to study the formation in reduced gravity of high quality nanoparticulate of novel materials using plasma synthesis. Particular emphasis will be placed on the production of powders of non-oxide materials like diamond, SiC, SiN, c-BN, etc. The objective of the study is to investigate the effect of gravity on plasma synthesis of these materials, and to determine how the microgravity synthesis can improve the quality and yield of the nanoparticles. It is expected that the reduced gravity will aid in the understanding of the controlling mechanisms of plasma synthesis, and will increase the yield, and quality of the synthesized powder. These materials have properties of interest in several industrial applications, such as high temperature load bearings or high speed metal machining. Furthermore, because of the nano-meter size of the particulate produced in this process, they have specific application in the fabrication of MEMS based combustion systems, and in the development and growth of nano-systems and nano-structures of these materials. These are rapidly advancing research areas, and there is a great need for high quality nanoparticles of different materials. One of the primary systems of interest in the project will be gas-phase synthesis of nanopowder of non-oxide materials.

  1. Quenching: fact or fiction?

    Science.gov (United States)

    Basketter, D

    2000-11-01

    Fragrance chemicals are a frequently reported cause of allergic contact dermatitis (ACD), a matter which has recently come into considerable prominence, to the point that legislation in Europe is under serious consideration. Certain skin-sensitizing fragrance chemicals have been reported by the producing industry to be rendered safe (quenched), at least in terms of ACD, when they are used in the presence of a specific quenching agent. Accordingly, it seemed timely to review this apparent quenching phenomenon, considering the available data and potential mechanistic hypotheses that might be used to explain it. If it is correct, it should be a phenomenon of potentially enormous value in the elimination of the allergenic properties of at least a proportion of common skin sensitizers. Whilst there is some evidence in man for the occurrence of quenching during the induction of skin sensitization, a much more substantial body of work has failed to find supportive evidence in various animals models, at a chemical level or at elicitation in human subjects with existing allergy. On balance, it is concluded that quenching of fragrance allergens is a phenomenon still awaiting positive evidence of existence.

  2. Austenite stabilization and high strength-elongation product of a low silicon aluminum-free hot-rolled directly quenched and dynamically partitioned steel

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Xiao-Dong [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Xu, Yun-Bo, E-mail: yunbo_xu@126.com [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Yang, Xiao-Long; Hu, Zhi-Ping; Peng, Fei [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Ju, Xiao-Wei [Ceri Long Product Co., Ltd., Beijing 100176 (China); Wu, Di [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China)

    2015-06-15

    Microstructures composed of lath martensite and retained austenite with volume fraction between 8.0 vol.% and 12.0 vol.% were obtained in a low-C low-Si Al-free steel through hot-rolling direct quenching and dynamical partitioning (HDQ&DP) processes. The austenite stabilization mechanism in the low-C low-Si Al-free steel under the special dynamical partitioning processes is investigated by analyzing the carbon partition behavior from martensite to austenite and the carbide precipitation-coarsening behavior in martensite laths combining with the possible hot rolling deformation inheritance. Results show that the satisfying retained austenite amount in currently studied low-Si Al-free HDQ&DP steel is caused by the high-efficiency carbon enrichment in the 30–80 nm thick regions of austenite near the interfaces in the hot-rolled ultra-fast cooled structure and the avoidance of serious carbides coarsening during the continuous cooling procedures. The excellent strength-elongation product reaching up to 26,000 MPa% shows that the involved HDQ&DP process is a promising method to develop a new generation of advanced high strength steel. - Highlights: • HDQ&DP processes were applied to a low-C low-Si Al-free steel. • Effective partitioning time during the continuous cooling processes is 1–220 s. • Retained austenite with volume fraction between 8.0 vol. % and 12.0 vol. % has been obtained. • The special austenite stabilization mechanism has been expounded.

  3. ROS/RNS Production in Water Using Various Discharge Plasma

    Science.gov (United States)

    Takahashi, Kazuhiro; Satoh, Kohki; Itoh, Hidenori; Kawaguchi, Hideki; Timoshkin, Igor; Given, Martin; MacGregor, Scott

    2015-09-01

    A pulsed discharge, a DC corona discharge and an atmospheric pressure plasma jet are generated above water, the off-gas of a packed-bed dielectric barrier discharge (PB-DBD) is sparged into water, and then reactive oxygen species and reactive nitrogen species in the water are investigated. H2O2, NO3- and a trace of NO2- are produced in the water after the plasma exposure. H2O2 concentration decreases when NO3- concentration increases, so that this is likely that OH radical to produce H2O2 by OH + OH -->H2O2 is consumed in the NO3- production by NO2 + OH --> HNO3 --> NO3-+ H+ (in water). Since no species is detected in water by the sparging of the PB-DBD off-gas containing more than 1000 ppm of O3, O3 does not contribute to produce H2O2 in water. Further, only NO3- is produced by the sparging of the off-gas containing N2O5 and HNO3. This leads that H2O2 and NO2- can be produced by short-lifetime species in plasma. In this work, the highest generation efficiency of H2O2 and NO2- are respectively 3,820 μg/Wh and 830 μg/Wh by the pulsed-plasma exposure, and that of NO3- is 2,530 μg/Wh by the off-gas sparging of the PB-DBD.

  4. 辊底式淬火炉在铝合金中厚板生产中的应用%Application of Roller-hearth Quenching Furnace in Production of Aluminum Alloy Plate

    Institute of Scientific and Technical Information of China (English)

    李志刚

    2015-01-01

    This paper reviewed the application and development of rol er-hearth quenching furnace in the production of aluminum al oy plate,and it il ustrated structural features and technical characteristics of the furnace.%介绍了辊底式淬火炉在铝合金中厚板生产中的应用情况,详细描述了辊底式淬火炉的结构特点和技术性能。

  5. Inhomogeneous Thermal Quenches

    CERN Document Server

    Sohrabi, Kiyoumars A

    2015-01-01

    We describe holographic thermal quenches that are inhomogeneous in space. The main characteristic of the quench is to take the system far from its equilibrium configuration. Except special extreme cases, the problem has no analytic solution. Using the numerical holography methods, we study different observables that measure thermalization such as the time evolution of the horizon, two-point Wightman function and entanglement entropy (EE). Having an extra nontrivial spacial direction, allows us to study this peculiar generalization since we categorize the problem based on whether we do the measurements along this special direction or perpendicular to it. Exciting new features appear that are absent in the common computations in the literature, the appearance of negative EE valleys surrounding the positive EE hills and abrupt quenches that occupy the whole space at their universal limit are some of the results of this paper. We have tried to provide physical explanations wherever possible. The physical picture ...

  6. The Quench Action

    Science.gov (United States)

    Caux, Jean-Sébastien

    2016-06-01

    We give a pedagogical introduction to the methodology of the Quench Action, which is an effective representation for the calculation of time-dependent expectation values of physical operators following a generic out-of-equilibrium state preparation protocol (for example a quantum quench). The representation, originally introduced in Caux and Essler (2013 Phys. Rev. Lett. 110 257203), is founded on a mixture of exact data for overlaps together with variational reasonings. It is argued to be quite generally valid and thermodynamically exact for arbitrary times after the quench (from short times all the way up to the steady state), and applicable to a wide class of physically relevant observables. Here, we introduce the method and its language, give an overview of some recent results, suggest a roadmap and offer some perspectives on possible future research directions.

  7. Quantum quenches during inflation

    CERN Document Server

    Carrilho, Pedro

    2016-01-01

    We propose a new technique to study fast transitions during inflation, by studying the dynamics of quantum quenches in an $O(N)$ scalar field theory in de Sitter spacetime. We compute the time evolution of the system using a non-perturbative large-$N$ limit approach. We derive the self-consistent mass equation for several physically relevant transitions of the parameters of the theory, in a slow motion approximation. Our computations reveal that the effective mass after the quench evolves in the direction of recovering its value before the quench, but stopping at a different asymptotic value, in which the mass is strictly positive. Furthermore, we tentatively find situations in which the effective mass can be temporarily negative, thus breaking the $O(N)$ symmetry of the system for a certain time, only to then come back to a positive value, restoring the symmetry. We argue the relevance of our new method in a cosmological scenario.

  8. Examining the Potential of Plasma-Assisted Pretreated Wheat Straw for Enzyme Production by Trichoderma reesei

    DEFF Research Database (Denmark)

    Rodríguez Gómez, Divanery; Lehmann, Linda Olkjær; Schultz-Jensen, Nadja

    2012-01-01

    Plasma-assisted pretreated wheat straw was investigated for cellulase and xylanase production by Trichoderma reesei fermentation. Fermentations were conducted with media containing washed and unwashed plasma-assisted pretreated wheat straw as carbon source which was sterilized by autoclavation...

  9. Cryogenic pellet production developments for long-pulse plasma operation

    Energy Technology Data Exchange (ETDEWEB)

    Meitner, S. J.; Baylor, L. R.; Combs, S. K.; Fehling, D. T.; McGill, J. M.; Duckworth, R. C.; McGinnis, W. D.; Rasmussen, D. A. [Oak Ridge National Laboratory, 1Bethel Valley Rd Oak Ridge, TN 37831 (United States)

    2014-01-29

    Long pulse plasma operation on large magnetic fusion devices require multiple forms of cryogenically formed pellets for plasma fueling, on-demand edge localized mode (ELM) triggering, radiative cooling of the divertor, and impurity transport studies. The solid deuterium fueling and ELM triggering pellets can be formed by extrusions created by helium cooled, twin-screw extruder based injection system that freezes deuterium in the screw section. A solenoid actuated cutter mechanism is activated to cut the pellets from the extrusion, inserting them into the barrel, and then fired by the pneumatic valve pulse of high pressure gas. Fuel pellets are injected at a rate up to 10 Hz, and ELM triggering pellets are injected at rates up to 20 Hz. The radiative cooling and impurity transport study pellets are produced by introducing impurity gas into a helium cooled section of a pipe gun where it deposits in-situ. A pneumatic valve is opened and propellant gas is released downstream where it encounters a passive punch which initially accelerates the pellet before the gas flow around the finishes the pellet acceleration. This paper discusses the various cryogenic pellet production techniques based on the twin-screw extruder, pipe gun, and pellet punch designs.

  10. Hydrogen production by coal plasma gasification for fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Galvita, V. [Max-Planck-Institute, Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106, Magdeburg (Germany); Messerle, V.E.; Ustimenko, A.B. [Research Department of Plasmotechnics, 22 Zvereva str., 050100 Almaty (Kazakhstan)

    2007-11-15

    Coal gasification in steam and air atmosphere under arc plasma conditions has been investigated with Podmoskovnyi brown coal, Kuuchekinski bituminous coal and Canadian petrocoke. It was found that for those coals the gasification degree to synthesis gas were 92.3%, 95.8 and 78.6% correspondingly. The amount of produced syngas was 30-40% higher in steam than in air gasification of the coal. The reduction of the carbon monoxide content in the hydrogen-rich reformate gas for low-temperature fuel cell applications normally involves high- and low-temperature water gas shift reactors followed by selective oxidation of residual carbon monoxide. It is shown that the carbon monoxide content can be reduced in one single reactor, which is based on an iron redox cycle. During the reduction phase of the cycle, the raw gas mixture of H{sub 2} and CO reduces a Fe{sub 3}O{sub 4}-CeO{sub 2}-ZrO{sub 2} sample, while during the oxidation phase steam re-oxidizes the iron and simultaneously hydrogen is being produced. The integration of the redox iron process with a coal plasma gasification technology in future allows the production of CO{sub x}-free hydrogen. (author)

  11. Chinese plasma-derived products supply under the lot release management system in 2007-2011.

    Science.gov (United States)

    Zhang, Xuejun; Ye, Shengliang; Du, Xi; Yuan, Jing; Zhao, Chaoming; Li, Changqing

    2013-11-01

    In 2007, the Chinese State Food and Drug Administration (SFDA) implemented a management system for lot release of all plasma-derived products. Since then, there have been only a few systematic studies of the blood supply, which is a concern when considering the small amount of plasma collected per capita (approximately 3 L/1000 people). As a result, there may be a threat to the safety of the available blood supply. In this study, we examined the characteristics of the supply of Chinese plasma-derived products. We investigated the reports of lot-released biological products derived from all 8 national or regional regulatory authorities in China from 2007 to 2011. The market supply characteristics of Chinese plasma-derived products were analyzed by reviewing the changes in supply varieties, the batches of lot-released plasma-derived products and the actual supply. As a result, the national regulatory authorities can more accurately develop a specific understanding of the production and quality management information provided by Chinese plasma product manufacturers. The implementation of the lot release system further ensures the clinical validity of the plasma-derived products in China and improves the safety of using plasma-derived products. This work provides an assessment of the future Chinese market supply of plasma-derived products and can function as a theoretical basis for the establishment of hemovigilance. Copyright © 2013 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  12. The Main Plasma Chemical Process of Nitric Oxide Production by Arc Discharge%The Main Plasma Chemical Process of Nitric Oxide Production by Arc Discharge

    Institute of Scientific and Technical Information of China (English)

    杨旗; 胡辉; 陈卫鹏; 许杰; 张锦丽; 吴双

    2011-01-01

    By adopting the optical multi-channel analyzer combined with fourier transform infrared (FTIR) spectrometer, the dominant free radicals and products generated by arc discharge were measured and studied, and the main plasma chemical reaction process in the nitric oxide production by arc discharge was identified. Plasma chemical kinetic curves of O, O2, N2, N and NO were simulated by using CHEMKIN and MATLAB. The results show that the main plasma chemical reaction process of nitric oxide production by arc discharge is a replacement reaction between O and N2, where NO can be generated instantaneously when discharging reaches stable.

  13. Intermediate mass dilepton production during the chemical equilibration of quark gluon plasma

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The production of dileptons from the chemically equilibrating quark gluon plasma in the intermediate mass region has been studied. Comparing with the calculated results based on the thermodynamic equilibrium system of quark gluon plasma, it has been found that the quark phase of the chemically equilibrating system gives rise to an even larger enhancement of the dileptons production. Therefore, such an enhancement of dilepton production may signal the formation of quark gluon plasma.

  14. Production of field-reversed mirror plasma with a coaxial plasma gun

    Science.gov (United States)

    Hartman, C.W.; Shearer, J.W.

    The use of a coaxial plasma gun to produce a plasma ring which is directed into a magnetic field so as to form a field-reversed plasma confined in a magnetic mirror. Plasma thus produced may be used as a target for subsequent neutral beam injection or other similarly produced and projected plasma rings or for direct fusion energy release in a pulsed mode.

  15. Quench studies of ILC cavities

    Energy Technology Data Exchange (ETDEWEB)

    Eremeev, Grigory; Geng, Rongli; Palczewski, Ari; Dai, Jin

    2011-07-01

    Quench limits accelerating gradient in SRF cavities to a gradient lower than theoretically expected for superconducting niobium. Identification of the quenching site with thermometry and OST, optical inspection, and replica of the culprit is an ongoing effort at Jefferson Lab aimed at better understanding of this limiting phenomenon. In this contribution we present our finding with several SRF cavities that were limited by quench.

  16. Quench Protection of DI-BSCCO Coil

    Science.gov (United States)

    Yamaguchi, T.; Ueno, E.; Kato, T.; Hayashi, K.

    Quench protection is one of the most important requirements for the practical application of high-temperature-superconducting (HTS) coils. Quench protection requires that early detection of a developing quench event is followed by rapid reduction of the operating current. However, such quench detection is very difficult because HTS wire produces heat only locally due to the very slow propagation velocity of a normal zone. Excellent high voltage insulation performance is required if the current is to be reduced rapidly in a large-scale superconducting application with very large inductance. Thus it is important to investigate the behavior of coils with various decay time constants, and to detect voltages on very short time scales. This goal remains to be achieved. In the present study we built test coil and a full-scale pole coil for a 20 MW motor for use in experiments on quench protection, and parameterized the relation between the decay time constant and the detecting voltage, using a conventional balance circuit to detect the quench, which was generated by gradually raising the temperature of the coils. The results verify that a balance circuit can be used for quench detection. For example, when the current decay time constant is 4 seconds, the test coil can be protected even with a detecting voltage of 0.15 volts, despite a significant heat production rate of 126 W. We also confirmed that the full-scale pole coil, with a decay time constant of 20 seconds, can be protected with a detecting voltage of 0.06 V.

  17. Quenched effective population size

    CERN Document Server

    Sagitov, Serik; Vatutin, Vladimir

    2010-01-01

    We study the genealogy of a geographically - or otherwise - structured version of the Wright-Fisher population model with fast migration. The new feature is that migration probabilities may change in a random fashion. Applying Takahashi's results on Markov chains with random transition matrices, we establish convergence to the Kingman coalescent, as the population size goes to infinity. This brings a novel formula for the coalescent effective population size (EPS). We call it a quenched EPS to emphasize the key feature of our model - random environment. The quenched EPS is compared with an annealed (mean-field) EPS which describes the case of constant migration probabilities obtained by averaging the random migration probabilities over possible environments.

  18. Calculating Quenching Weights

    CERN Document Server

    Salgado, C A; Salgado, Carlos A.; Wiedemann, Urs Achim

    2003-01-01

    We calculate the probability (``quenching weight'') that a hard parton radiates an additional energy fraction due to scattering in spatially extended QCD matter. This study is based on an exact treatment of finite in-medium path length, it includes the case of a dynamically expanding medium, and it extends to the angular dependence of the medium-induced gluon radiation pattern. All calculations are done in the multiple soft scattering approximation (Baier-Dokshitzer-Mueller-Peign\\'e-Schiff--Zakharov ``BDMPS-Z''-formalism) and in the single hard scattering approximation (N=1 opacity approximation). By comparison, we establish a simple relation between transport coefficient, Debye screening mass and opacity, for which both approximations lead to comparable results. Together with this paper, a CPU-inexpensive numerical subroutine for calculating quenching weights is provided electronically. To illustrate its applications, we discuss the suppression of hadronic transverse momentum spectra in nucleus-nucleus colli...

  19. Phenomenology of Holographic Quenches

    Science.gov (United States)

    da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre

    2015-10-01

    We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.

  20. Simulation of the Quench-06 experiment with Scdapsim; Simulacion del experimento Quench-06 con Scdapsim

    Energy Technology Data Exchange (ETDEWEB)

    Angel M, E. del; Nunez C, A.; Amador G, R. [CNSNS, Dr. Barragan No. 779, 03020 Mexico D.F. (Mexico)]. e-mail: edangelm@cnsns.gob.mx

    2003-07-01

    The present work describes the pattern of the called Quench installation developed and used by the National Commission of Nuclear Security and Safeguards (CNSNS) for their participation in the International Standard Problem 45 (ISP), organized by the Nuclear Energy Agency (NEA). The exercise consisted on the simulation of the denominated experiment Quench-06 carried out in the experimental installation Quench located in the Forschungszentrum laboratory in Karlsruhe, Germany. The experiment Quench-06 consisted on simulating the sudden and late injection of water in a fuel assemble for a pressurized reactor (PWR). The CNSNS uses the version bd of the SCDAPSIM code developed by the company Innovative Software Systems (ISS) to simulate this experiment. The obtained results showed that the code is able to predict the experiment partially when overestimating the hydrogen production and of the partial fused of some fuel pellets, but predicting correctly the damage in the shroud. (Author)

  1. Production of stable isotopes utilizing the plasma separation process

    Science.gov (United States)

    Bigelow, T. S.; Tarallo, F. J.; Stevenson, N. R.

    2005-12-01

    A plasma separation process (PSP) is being operated at Theragenics Corporation's®, Oak Ridge, TN, facility for the enrichment of stable isotopes. The PSP utilizes ion cyclotron mass discrimination to separate isotopes on a relatively large scale. With a few exceptions, nearly any metallic element could be processed with PSP. Output isotope enrichment factor depends on natural abundance and mass separation and can be fairly high in some cases. The Theragenics™ PSP facility is believed to be the only such process currently in operation. This system was developed and formerly operated under the US Department of Energy Advanced Isotope Separation program. Theragenics™ also has a laboratory at the PSP site capable of harvesting the isotopes from the process and a mass spectrometer system for analyzing enrichment and product purity. Since becoming operational in 2002, Theragenics™ has utilized the PSP to separate isotopes of several elements including: dysprosium, erbium, gadolinium, molybdenum and nickel. Currently, Theragenics™ is using the PSP for the separation of 102Pd, which is used as precursor for the production of 103Pd. The 103Pd radioisotope is the active ingredient in TheraSeed®, which is used in the treatment of early stage prostate cancer and being investigated for other medical applications. New industrial, medical and research applications are being investigated for isotopes that can be enriched on the PSP. Pre-enrichment of accelerator or reactor targets offers improved radioisotope production. Theragenics operates 14 cyclotrons for proton activation and has access to HFIR at ORNL for neutron activation of radioisotopes.

  2. A Hybrid Strong/Weak Coupling Approach to Jet Quenching

    CERN Document Server

    Casalderrey-Solana, Jorge; Milhano, José Guilherme; Pablos, Daniel; Rajagopal, Krishna

    2014-01-01

    We propose and explore a new hybrid approach to jet quenching in a strongly coupled medium. The basis of this phenomenological approach is to treat physics processes at different energy scales differently. The high-$Q^2$ processes associated with the QCD evolution of the jet from production as a single hard parton through its fragmentation, up to but not including hadronization, are treated perturbatively. The interactions between the partons in the shower and the deconfined matter within which they find themselves lead to energy loss. The momentum scales associated with the medium (of the order of the temperature) and with typical interactions between partons in the shower and the medium are sufficiently soft that strongly coupled physics plays an important role in energy loss. We model these interactions using qualitative insights from holographic calculations of the energy loss of energetic light quarks and gluons in a strongly coupled plasma, obtained via gauge/gravity duality. We embed this hybrid model ...

  3. Production of selective membranes using plasma deposited nanochanneled thin films

    Directory of Open Access Journals (Sweden)

    Rodrigo Amorim Motta Carvalho

    2006-12-01

    Full Text Available The hydrolization of thin films obtained by tetraethoxysilane plasma polymerization results in the formation of a nanochanneled silicone like structure that could be useful for the production of selective membranes. Therefore, the aim of this work is to test the permeation properties of hydrolyzed thin films. The films were tested for: 1 permeation of polar organic compounds and/or water in gaseous phase and 2 permeation of salt in liquid phase. The efficiency of permeation was tested using a quartz crystal microbalance (QCM technique in gas phase and conductimetric analysis (CA in liquid phase. The substrates used were: silicon for characterization of the deposited films, piezoelectric quartz crystals for tests of selective membranes and cellophane paper for tests of permeation. QCM analysis showed that the nanochannels allow the adsorption and/or permeation of polar organic compounds, such as acetone and 2-propanol, and water. CA showed that the films allow salt permeation after an inhibition time needed for hydrolysis of the organic radicals within the film. Due to their characteristics, the films can be used for grains protection against microorganism proliferation during storage without preventing germination.

  4. Plasma adiponectin and endogenous glucose production in humans

    DEFF Research Database (Denmark)

    Stefan, Norbert; Stumvoll, Michael; Vozarova, Barbora

    2003-01-01

    High plasma adiponectin is associated with reduced risk of type 2 diabetes, probably a consequence of its insulin-sensitizing properties. In vivo data in rodents suggest that the insulin-sensitization responsible for improvement of glycemia occurs in muscle and liver. Whereas associations of plasma...... adiponectin with muscle insulin sensitivity in humans have been examined, this has not been done for the liver....

  5. Design of Industrial Quenching Processes

    Institute of Scientific and Technical Information of China (English)

    Nikolai. I. KOBASKO; George .E. TOTTEN

    2004-01-01

    The method of designing industrial processes of quench cooling, in particular, the speed of the conveyor movement with regard to shape and sizes of parts to be quenched, thermal and physical properties of material and cooling capacity of quenchants has been developed. The suggested designing method and databases are the basis for the complete automation of industrial processes of quench cooling, especially for continuous conveyor lines, with the purpose of making high-strength materials. The process is controlled by infrared technique.

  6. Modeling of plasma jet production from rail and coaxial guns for imploding plasma liner formation*

    Science.gov (United States)

    Mason, R. J.; Faehl, R. J.; Kirikpatrick, R. C.; Witherspoon, D.; Cassibry, J.

    2010-11-01

    We study the generation of plasma jets for forming imploding plasma liners using an enhanced version of the ePLAS implicit/hybrid model.^1 Typically, the jets are partially ionized D or Ar gases, in initial 3-10 cm long slugs at 10^16-10^18 electron/cm^3, accelerated for microseconds along 15-30 cm rail or coaxial guns with a 1 cm inter-electrode gap and driven by magnetic fields of a few Tesla. We re-examine the B-field penetration mechanisms that can be active in such wall-connected plasmas,^2 including erosion and EMHD influences, which can subsequently impact plasma liner formation and implosion. For the background and emitted plasma components we discuss optimized PIC and fluid modeling techniques, and the use of implicit fields and hybridized electrons to speed simulation. The plasmas are relatively cold (˜3 eV), so results with fixed atomic Z are compared to those from a simple analytic EOS, and allowing radiative heat loss from the plasma. The use of PIC ions is explored to extract large mean-free-path kinetic effects. 1. R. J. Mason and C. Cranfill, IEEE Trans. Plasma Sci. PS-14, 45 (1986) 2. R. Mason, et al., Phys. Fluids B, 5, 1115 (1993). [4pt] *Research supported in part by USDOE Grant DE-SC0004207.

  7. Hydrogen production by plasma electrolysis reactor of KOH-ethanol solution

    Science.gov (United States)

    Saksono, N.; Batubara, T.; Bismo, S.

    2016-11-01

    Plasma electrolysis has great potential in industrial hydrogen production, chlor-alkali production, and waste water treatment. Plasma electrolysis produces more hydrogen with less energy consumption than hydrocarbon or Faraday electrolysis. This paper investigated the hydrogen production by plasma electrolysis of KOH-ethanol solution at 80 °C and 1 atm. The effects of voltage, KOH solution, ethanol addition, and cathode deep on plasma electrolysis performance were studied. The hydrogen production was analyzed using bubble flow meter and hydrogen analyzer. The electrical energy consumption was measured by a digital multimeter. The effectiveness of plasma electrolysis in terms of hydrogen production was evaluated by comparing it with Faraday Electrolysis. The results showed that hydrogen produced by plasma electrolysis is 149 times higher than the hydrogen produced by Faraday electrolysis. The optimum hydrogen production was 50.71 mmol/min, obtained at 700 V with 0.03 M KOH, 10% vol ethanol and 6.6 cm cathode deep, with energy consumption 1.49 kJ/mmol. The result demonstrates a promising path for hydrogen production by utilizing plasma electrolysis reactor.

  8. Plasma proteins production and excretion in diabetic nephropathy in ...

    African Journals Online (AJOL)

    Journal of African Association of Physiological Sciences ... Subjects, materials, and methods: Plasma albumin, and fibrinogen ... Results: A direct relationship was found between albuminuria and albumin concentration (r=0.59, p<0.05).

  9. Plasma reforming of glycerol for synthesis gas production.

    Science.gov (United States)

    Zhu, Xinli; Hoang, Trung; Lobban, Lance L; Mallinson, Richard G

    2009-05-28

    Glycerol can be effectively converted to synthesis gas (selectivity higher than 80%) with small amounts of water or no water using plasmas at low temperature and atmospheric pressure, without external heating.

  10. Tempering/ageing in region 50 – 600 °C of quenched and cold deformed 585 GOLD alloy for jewelry production

    Directory of Open Access Journals (Sweden)

    R. Perić

    2014-04-01

    Full Text Available Numerous gold alloys posses the ability for thermal hardening, and this property is attractive for improving jewels strength, because the most noble alloys are weak. The thermal treating below the recrystallization temperature, is kind of tempering but also age-hardening. In this paper is made an attempt for studying the possibility for thermal hardening of 585 golden alloy. The goal is to increase the mechanical properties. Those demands could be reached by metallurgical controlling of phase transformations аnd proper thermal treating. Here is studied behavior of quenched and cold deformed gold alloy 585 after tempering/ageing in temperature region 50 - 600 °C, in intervals of 50 °C. The highest hardness values are obtained at temperatures about 200 °C for both initial states.

  11. Tetraquarks Production in Quark-Gluon Plasma with Diquarks

    Institute of Scientific and Technical Information of China (English)

    MA Zhong-Biao; GAO Chong-Shou

    2006-01-01

    @@ We present a way to calculate tetraquarks ratios for quark-gluon plasma with diquarks. The ratios of tetraquarks over baryons produced from quark matter are high than hadronic gas model limits. It is a better way to search for four-quark states in relativistic heavy ion collisions. It may become a criterion to judge whether quark-gluon plasma has formed to search for four-quark states in relativistic heavy ion collisions.

  12. Strangeness Production in a Chemically Equilibrating Quark-Gluon Plasma

    Institute of Scientific and Technical Information of China (English)

    HE Ze-Jun; LONG Jia-Li; MA Yu-Gang; MA Guo-Liang

    2004-01-01

    @@ We study the strangeness of a chemically equilibrating quark-gluon plasma at finite baryon density based on the and will accelerate with the change of the initial system from a chemically non-equilibrated to an equilibrated system. We also find that the calculated strangeness is very different from the one in the thermodynamic equilibrium system. This study may be helpful to understand the formation of quark-gluon plasma via a chemically non-equilibrated evolution framework.

  13. Dark matter annihilation and jet quenching phenomena in the early universe

    CERN Document Server

    Mishustin, Igor N

    2016-01-01

    Dark-matter particles like neutralinos should decouple from the hot cosmic plasma at temperatures of about 40 GeV. Later they can annihilate each other into standard-model particles, which are injected into the dense primordial plasma and quickly loose energy. This process is similar to jet quenching in ultrarelativistic heavy-ion collisions, actively studied in RHIC and LHC experiments. Using empirical information from heavy-ion experiments I show that the cosmological (anti)quark and gluon jets are damped very quickly until the plasma remains in the deconfined phase. The charged hadron and lepton jets are strongly damped until the recombination of electrons and protons. The consequences of energy transfer by the annihilation products to the cosmic matter are discussed.

  14. Cold Atmospheric Plasma: methods of production and application in dentistry and oncology

    OpenAIRE

    Hoffmann, Clotilde; Berganza, Carlos; Zhang, John

    2013-01-01

    Cold Atmospheric Plasma is an ionized gas that has recently been extensively studied by researchers as a possible therapy in dentistry and oncology. Several different gases can be used to produce Cold Atmospheric Plasma such as Helium, Argon, Nitrogen, Heliox, and air. There are many methods of production by which cold atmospheric plasma is created. Each unique method can be used in different biomedical areas. In dentistry, researchers have mostly investigated the antimicrobial effects produc...

  15. LHC BFPP Quench Test with Ions (2015)

    CERN Document Server

    Schaumann, Michaela; Bahamonde Castro, Cristina; Auchmann, Bernhard; Chetvertkova, Vera; Giachino, Rossano; Jowett, John; Kalliokoski, Matti; Lechner, Anton; Mertens, Tom; Ponce, Laurette; CERN. Geneva. ATS Department

    2016-01-01

    The 2015 Pb-Pb collision run of the LHC operated at a beam energy of 6.37Z TeV. The power of the secondary beams emitted from the interaction point by the bound-free pair production (BFPP) process reached new levels while the propensity of the bending magnets to quench is higher at the new magnetic field levels. This beam power is about 70 times greater than that contained in the luminosity debris and is focussed on a specific location. As long foreseen, orbit bumps were introduced in the dispersion suppressors around the highest luminosity experiments to mitigate the risk of quenches by displacing and spreading out these losses. Because the impact position and intensity of these secondary beams is well known and can be tracked easily with the Beam Loss Monitors (BLMs), the BFPP1 beam (208Pb81+ ions), which is the most intense, provides a tool to accurately measure the steady state quench limit of the LHC main dipoles. At the moment the exact quench limit is not known, but this knowledge is important to asses...

  16. Effect of methadone on plasma arginine vasopressin level and urine production in conscious dogs

    NARCIS (Netherlands)

    Hellebrekers, L.J.; Mol, J.A.; Brom, W.E. van den; Wimersma Greidanus, T.B. van

    1987-01-01

    The aim of this study was to examine the effect of i.v. methadone on the plasma arginine-vasopressin (AVP) levels and urine production in 9 conscious dogs. A highly significant increase from the baseline plasma AVP values of below 3 pg/ml occurred within 5 min following methadone administration. Max

  17. Energy upgrade as regards quench performance

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W.W.; Tepikian, S.

    2011-01-01

    Since the cross section for W production increases rapidly with energy, we consider the possibility of increasing the collision energy of polarized protons at RHIC. The limits of present hardware are examined with a particular emphasis on the quench training performance of magnets. Ignoring the limits of the DX magnets, the short-sample currents for the main arc (8 cm) dipoles could allow an increase of more than 30%, however we estimate 400 to 500 training quenches for the just 8 cm dipoles to reach this level. We propose that a 10% increase in energy might be achieved with the present hardware configuration. Raising the beam energy to 275 GeV ({radical}s = 550 GeV) should increase the W production rate by almost 50% from the 250 GeV level for the same optics with identical {beta}*'s at the collision points.

  18. A New Quenching Process and Tower to Improve the Recovery of Acrylonitrile

    Institute of Scientific and Technical Information of China (English)

    甘永胜; 顾军民; 方永成

    2004-01-01

    Quenching process and design of the quenching tower in acrylonitrile production in China were studied in order to decrease the polymerization loss of acrylonitrile in the quenching tower. Based on the research of acrylonitrile polymerization in the quenching tower, a new quenching process was proposed to avoid the disadvantages of the original process. Two kinds of internals were installed to improve the performance of the quenching tower. Through a series of air-flow and real-flow model experiments, the new quenching process and new design were showed to be successful in enhancing the mass and heat transfer in the vapor-liquid system and decreasing the loss of acrylonitrile.Industrial application showed satisfactory results of decrease of the acrylonitrile loss in the quenching tower by about 4.5% and increase of the acrylonitrile recovery of the whole plant by more than 4%.

  19. Hard photon production from unsaturated quark-gluon plasma at two-loop level

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, D. E-mail: ddutta@apsara.barc.ernet.in; Sastry, S.V.S.; Mohanty, A.K.; Kumar, K

    2002-11-18

    The hard photon production from bremsstrahlung and annihilation with scattering that arise at two-loop level are estimated for a chemically non-equilibrated quark-gluon plasma in the framework of Hard Thermal Loop (HTL) resummed effective field theory. The rate of photon production is found to be suppressed due to unsaturated phase space compared to equilibrated plasma. For an unsaturated plasma, unlike the effective one-loop case, the reduction in the effective two-loop processes is found to be independent of gluon fugacity, due to an additional collinear enhancement arising from the decrease in thermal quark mass but strongly depends on quark and antiquark fugacities. It is also found that the photon production is dominated by bremsstrahlung mechanism, since the phase space suppression is higher for annihilation with scattering, in contrast to the equilibrated plasma where annihilation with scattering dominates the photon production.

  20. Jet quenching from QCD evolution

    Science.gov (United States)

    Chien, Yang-Ting; Emerman, Alexander; Kang, Zhong-Bo; Ovanesyan, Grigory; Vitev, Ivan

    2016-04-01

    Recent advances in soft-collinear effective theory with Glauber gluons have led to the development of a new method that gives a unified description of inclusive hadron production in reactions with nucleons and heavy nuclei. We show how this approach, based on the generalization of the DGLAP evolution equations to include final-state medium-induced parton shower corrections for large Q2 processes, can be combined with initial-state effects for applications to jet quenching phenomenology. We demonstrate that the traditional parton energy loss calculations can be regarded as a special soft-gluon emission limit of the general QCD evolution framework. We present phenomenological comparison of the SCETG -based results on the suppression of inclusive charged hadron and neutral pion production in √{sNN }=2.76 TeV lead-lead collisions at the Large Hadron Collider to experimental data. We also show theoretical predictions for the upcoming √{sNN }≃5.1 TeV Pb +Pb run at the LHC.

  1. Plasma production by means of discharge in a spherical cavity

    NARCIS (Netherlands)

    Antsiferov, P. S.; Dorokhin, L. A.; Koshelev, K. N.

    2010-01-01

    The work is devoted to the study of plasma, appearing as a result of cumulation of shock wave with form close to spherical. The shock wave was obtained by triggering of fast discharge (dI/dt about 10(12) A/s) on inner surface of cavity, made from insulator. Spherical cavity with radius 4.5 mm was fi

  2. Cold Atmospheric Plasma: methods of production and application in dentistry and oncology.

    Science.gov (United States)

    Hoffmann, Clotilde; Berganza, Carlos; Zhang, John

    2013-01-01

    Cold Atmospheric Plasma is an ionized gas that has recently been extensively studied by researchers as a possible therapy in dentistry and oncology. Several different gases can be used to produce Cold Atmospheric Plasma such as Helium, Argon, Nitrogen, Heliox, and air. There are many methods of production by which cold atmospheric plasma is created. Each unique method can be used in different biomedical areas. In dentistry, researchers have mostly investigated the antimicrobial effects produced by plasma as a means to remove dental biofilms and eradicate oral pathogens. It has been shown that reactive oxidative species, charged particles, and UV photons play the main role. Cold Atmospheric Plasma has also found a minor, but important role in tooth whitening and composite restoration. Furthermore, it has been demonstrated that Cold Atmospheric Plasma induces apoptosis, necrosis, cell detachment, and senescence by disrupting the S phase of cell replication in tumor cells. This unique finding opens up its potential therapy in oncology.

  3. Effects of the plasma profiles on photon and pair production in ultrahigh intensity laser solid interaction

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Y. X.; Jin, X. L., E-mail: jinxiaolin@uestc.edu.cn; Yan, W. Z.; Li, J. Q.; Li, B. [Vacuum Electronics National Laboratory, University of Electronic Science and Technology of China, Chengdu 610054 (China); Yu, J. Q. [Vacuum Electronics National Laboratory, University of Electronic Science and Technology of China, Chengdu 610054 (China); John Adams Institute for Accelerator Science, Imperial College London, London SW7 2AZ (United Kingdom)

    2015-12-15

    The model of photon and pair production in strong field quantum electrodynamics is implemented into our 1D3V particle-in-cell code with Monte Carlo algorithm. Using this code, the evolution of the particles in ultrahigh intensity laser (∼10{sup 23} W/cm{sup 2}) interaction with aluminum foil target is observed. Four different initial plasma profiles are considered in the simulations. The effects of initial plasma profiles on photon and pair production, energy spectra, and energy evolution are analyzed. The results imply that one can set an optimal initial plasma profile to obtain the desired photon distributions.

  4. Quench-induced trapping of magnetic flux in annular

    DEFF Research Database (Denmark)

    Aaroe, M.; Monaco, R.; Rivers, R.;

    2008-01-01

    over 4 orders of magnitude. After the quench the result of the spontaneous production of topological defects, trapped fluxons, is unambiguously observed as zero-field steps in the DC I-V characteristic of the junction. A power-law scaling behavior of trapping probability versus quench rate is found...... with a critical exponent of 0.5 (within experimental error). The main experimental challenges are to generate many identical quenches with accurate cooling rate, to automate data analysis and acquisition, and to suppress external magnetic fields and noise by passive magnetic shielding and compensation....

  5. Control of ROS and RNS productions in liquid in atmospheric pressure plasma-jet system

    Science.gov (United States)

    Uchida, Giichiro; Ito, Taiki; Takenaka, Kosuke; Ikeda, Junichiro; Setsuhara, Yuichi

    2016-09-01

    Non-thermal plasma jets are of current interest in biomedical applications such as wound disinfection and even treatment of cancer tumors. Beneficial therapeutic effects in medical applications are attributed to excited species of oxygen and nitrogen from air. However, to control the production of these species in the plasma jet is difficult because their production is strongly dependent on concentration of nitrogen and oxygen from ambient air into the plasma jet. In this study, we analyze the discharge characteristics and the ROS and RNS productions in liquid in low- and high-frequency plasma-jet systems. Our experiments demonstrated the marked effects of surrounding gas near the plasma jet on ROS and RNS productions in liquid. By controlling the surround gas, the O2 and N2 main plasma jets are selectively produced even in open air. We also show that the concentration ratio of NO2- to H2O2 in liquid is precisely tuned from 0 to 0.18 in deionized water by changing N2 gas ratio (N2 / (N2 +O2)) in the main discharge gas, where high NO2- ratio is obtained at N2 gas ratio at N2 / (N2 +O2) = 0 . 8 . The low-frequency plasma jet with controlled surrounding gas is an effective plasma source for ROS and RNS productions in liquid, and can be a useful tool for biomedical applications. This study was partly supported by a Grant-in-Aid for Scientific Research on Innovative Areas ``Plasma Medical Innovation'' (24108003) from the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT).

  6. Product surface hardening in non-self-sustained glow discharge plasma before synthesis of superhard coatings

    Science.gov (United States)

    Krasnov, P. S.; Metel, A. S.; Nay, H. A.

    2017-05-01

    Before the synthesis of superhard coating, the product surface is hardened by means of plasma nitriding, which prevents the surface deformations and the coating brittle rupture. The product heating by ions accelerated from plasma by applied to the product bias voltage leads to overheating and blunting of the product sharp edges. To prevent the blunting, it is proposed to heat the products with a broad beam of fast nitrogen molecules. The beam injection into a working vacuum chamber results in filling of the chamber with quite homogeneous plasma suitable for nitriding. Immersion in the plasma of the electrode and heightening of its potential up to 50-100 V initiate a non-self-sustained glow discharge between the electrode and the chamber. It enhances the plasma density by an order of magnitude and reduces its spatial nonuniformity down to 5-10%. When a cutting tool is isolated from the chamber, it is bombarded by plasma ions with an energy corresponding to its floating potential, which is lower than the sputtering threshold. Hence, the sharp edges are sputtered only by fast nitrogen molecules with the same rate as other parts of the tool surface. This leads to sharpening of the cutting tools instead of blunting.

  7. Holographic Quenches with a Gap

    CERN Document Server

    da Silva, Emilia; Mas, Javier; Serantes, Alexandre

    2016-01-01

    In order to holographically model quenches with a gapped final hamiltonian, we consider a gravity-scalar theory in anti-de Sitter space with an infrared hard wall. We allow a time dependent profile for the scalar field at the wall. This induces an energy exchange between bulk and wall and generates an oscillating scalar pulse. We argue that such backgrounds are the counterpart of quantum revivals in the dual field theory. We perform a qualitative comparison with the quench dynamics of the massive Schwinger model, which has been recently analyzed using tensor network techniques. Agreement is found provided the width of the oscillating scalar pulse is inversely linked to the energy density communicated by the quench. We propose this to be a general feature of holographic quenches.

  8. Holographic quenches with a gap

    Science.gov (United States)

    da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre

    2016-06-01

    In order to holographically model quenches with a gapped final hamiltonian, we consider a gravity-scalar theory in anti-de Sitter space with an infrared hard wall. We allow a time dependent profile for the scalar field at the wall. This induces an energy exchange between bulk and wall and generates an oscillating scalar pulse. We argue that such backgrounds are the counterpart of quantum revivals in the dual field theory. We perform a qualitative comparison with the quench dynamics of the massive Schwinger model, which has been recently analyzed using tensor network techniques. Agreement is found provided the width of the oscillating scalar pulse is inversely linked to the energy density communicated by the quench. We propose this to be a general feature of holographic quenches.

  9. Probing strongly coupled anisotropic plasmas from higher curvature gravity

    Energy Technology Data Exchange (ETDEWEB)

    Jahnke, Viktor; Misobuchi, Anderson Seigo [Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo (Brazil)

    2016-06-15

    We consider five-dimensional AdS-axion-dilaton gravity with a Gauss-Bonnet term and use a black brane solution displaying spatial anisotropy as the gravity dual of a strongly coupled anisotropic plasma. We compute several observables relevant to the study of the plasma, namely, the drag force, the jet quenching parameter, the quarkonium potential, and the thermal photon production. The effects of higher derivative corrections and of the anisotropy are discussed and compared with previous results. (orig.)

  10. Probing strongly coupled anisotropic plasmas from higher curvature gravity

    CERN Document Server

    Misobuchi, Anderson Seigo

    2015-01-01

    We consider five-dimensional AdS-axion-dilaton gravity with a Gauss-Bonnet term and use a black brane solution displaying spatial anisotropy as the gravity dual of a strongly coupled anisotropic plasma. We compute several observables relevant to the study of the plasma, namely, the drag force, the jet quenching parameter, the quarkonium potential and the thermal photon production. The effects of higher derivative corrections and of the anisotropy are discussed and compared with previous results.

  11. Probing strongly coupled anisotropic plasmas from higher curvature gravity

    Science.gov (United States)

    Jahnke, Viktor; Misobuchi, Anderson Seigo

    2016-06-01

    We consider five-dimensional AdS-axion-dilaton gravity with a Gauss-Bonnet term and use a black brane solution displaying spatial anisotropy as the gravity dual of a strongly coupled anisotropic plasma. We compute several observables relevant to the study of the plasma, namely, the drag force, the jet quenching parameter, the quarkonium potential, and the thermal photon production. The effects of higher derivative corrections and of the anisotropy are discussed and compared with previous results.

  12. Tunable Electron Multibunch Production in Plasma Wakefield Accelerators

    CERN Document Server

    Hidding, B; Wittig, G; Aniculaesei, C; Jaroszynski, D; McNeil, B W J; Campbell, L T; Islam, M R; Ersfeld, B; Sheng, Z -M; Xi, Y; Deng, A; Rosenzweig, J B; Andonian, G; Murokh, A; Hogan, M J; Bruhwiler, D L; Cormier, E

    2014-01-01

    Synchronized, independently tunable and focused $\\mu$J-class laser pulses are used to release multiple electron populations via photo-ionization inside an electron-beam driven plasma wave. By varying the laser foci in the laboratory frame and the position of the underdense photocathodes in the co-moving frame, the delays between the produced bunches and their energies are adjusted. The resulting multibunches have ultra-high quality and brightness, allowing for hitherto impossible bunch configurations such as spatially overlapping bunch populations with strictly separated energies, which opens up a new regime for light sources such as free-electron-lasers.

  13. Accessibility condition of wave propagation and multicharged ion production in electron cyclotron resonance ion source plasma

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Yushi, E-mail: kato@eei.eng.osaka-u.ac.jp; Yano, Keisuke; Nishiokada, Takuya; Nagaya, Tomoki; Kimura, Daiju; Kumakura, Sho; Imai, Youta; Hagino, Shogo; Otsuka, Takuro; Sato, Fuminobu [Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan)

    2016-02-15

    A new tandem type source of electron cyclotron resonance (ECR) plasmas has been constructing for producing synthesized ion beams in Osaka University. Magnetic mirror field configuration with octupole magnets can be controlled to various shape of ECR zones, namely, in the 2nd stage plasma to be available by a pair mirror and a supplemental coil. Noteworthy correlations between these magnetic configurations and production of multicharged ions are investigated in detail, as well as their optimum conditions. We have been considering accessibility condition of electromagnetic and electrostatic waves propagating in ECR ion source plasma, and then investigated their correspondence relationships with production of multicharged ions. It has been clarified that there exits efficient configuration of ECR zones for producing multicharged ion beams experimentally, and then has been suggested from detail accessibility conditions on the ECR plasma that new resonance, i.e., upper hybrid resonance, must have occurred.

  14. Thermal charm and charmonium production in quark gluon plasma

    Directory of Open Access Journals (Sweden)

    Kai Zhou

    2016-07-01

    Full Text Available We study the effect of thermal charm production on charmonium regeneration in high energy nuclear collisions. By solving the kinetic equations for charm quark and charmonium distributions in Pb+Pb collisions, we calculate the global and differential nuclear modification factors RAA(Npart and RAA(pt for J/ψ s. Due to the thermal charm production in hot medium, the charmonium production source changes from the initially created charm quarks at SPS, RHIC and LHC to the thermally produced charm quarks at Future Circular Collider (FCC, and the J/ψ suppression (RAA1 at FCC at low transverse momentum.

  15. The quenching time scale and quenching rate of galaxies

    CERN Document Server

    Lian, Jianhui; Zhang, Kai; Kong, Xu

    2016-01-01

    The average star formation rate (SFR) in galaxies has been declining since redshift of 2. A fraction of galaxies quench and become quiescent. We constrain two key properties of the quenching process: the quenching time scale and the quenching rate among galaxies. We achieve this by analyzing the galaxy number density profile in NUV-u color space and the distribution in NUV-u v.s. u-i color-color diagram with a simple toy-model framework. We focus on galaxies in three mass bins between 10 to 10 and 10 to 10.6 solar mass. In the NUV-u v.s. u-i color-color diagram, the red u-i galaxies exhibit a different slope from the slope traced by the star-forming galaxies. This angled distribution and the number density profile of galaxies in NUV-u space strongly suggest that the decline of the SFR in galaxies has to accelerate before they turn quiescent. We model this color-color distribution with a two-phase exponential decline star formation history. The models with an e-folding time in the second phase (the quenching p...

  16. Plasma torch production of Ti/Al nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, Jonathan [Los Alamos National Laboratory; Zea, Hugo [UNM MECH.ENG; Cheng, Lily [UNM MECH.ENG.; Luhrs, Claudia [UNM MECH.ENG.; Courtney, Matthew [UNM MECH.ENG.

    2009-01-01

    Using the Aerosol-through-Plasma (A-T-P) technique high surface area bi-cationic (Ti-Al) oxide particles of a range of stoichiometries were produced that showed remarkable resistance to sintering. Specifically, we found that homogeneous nanoparticles with surface areas greater than 150 m{sup 2}/gm were produced at all stoichiometries. In particular, for particles with a Ti:Al ratio of 1:3 a surface area of just over 200 m{sup 2}/gm was measured using the BET method. The most significant characteristic of these particles was that their sinter resistance was far superior to that of TiAl particles produced using any other method. For example, A-T-P generated particles retained >70% of their surface area even after sintering at 1000 C for five hours. In contrast, particles made using all other methods lost virtually all of their surface area after an 800 C treatment.

  17. Thermodynamical study on production of acetylene from coal pyrolysis in hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F.; Guo, W.K.; Yuan, X.Q.; Zhao, T.Z. [Fudan University, Shanghai (China). Inst. for Modern Physics

    2006-05-15

    The chemical thermodynamic equilibrium of acetylene production by coal pyrolysis in hydrogen plasma was studied. The thermodynamic equilibrium is obtained by using the method of free energy. Calculated results show that the hydrogen concentration in the equilibrium system is very important for the acetylene production by coal conversion and the energy consumption for the production of acetylene per-kilogram strongly depends on the hydrogen concentration and the temperature.

  18. Thermodynamical Study on Production of Acetylene from Coal Pyrolysis in Hydrogen Plasma

    Science.gov (United States)

    Wang, Fei; Guo, Wenkang; Yuan, Xingqiu; Zhao, Taize

    2006-05-01

    The chemical thermodynamic equilibrium of acetylene production by coal pyrolysis in hydrogen plasma was studied. The thermodynamic equilibrium is obtained by using the method of free energy. Calculated results show that the hydrogen concentration in the equilibrium system is very important for the acetylene production by coal conversion and the energy consumption for the production of acetylene per-kilogram strongly depends on the hydrogen concentration and the temperature.

  19. Production characteristics of reactive oxygen/nitrogen species in water using atmospheric pressure discharge plasmas

    Science.gov (United States)

    Takahashi, Kazuhiro; Satoh, Kohki; Itoh, Hidenori; Kawaguchi, Hideki; Timoshkin, Igor; Given, Martin; MacGregor, Scott

    2016-07-01

    A pulsed discharge, a DC corona discharge, and a plasma jet are separately generated above a water surface, and reactive oxygen species and reactive nitrogen species (ROS/RNS) in the water are investigated. ROS/RNS in water after the sparging of the off-gas of a packed-bed dielectric barrier discharge (PB-DBD) are also investigated. H2O2, NO2 -, and NO3 - are detected after plasma exposure and only NO3 - after off-gas sparging. Short-lifetime species in plasma are found to play an important role in H2O2 and NO2 - production and long-lifetime species in NO3 - production. NO x may inhibit H2O2 production through OH consumption to produce HNO2 and HNO3. O3 does not contribute to ROS/RNS production. The pulsed plasma exposure is found to be effective for the production of H2O2 and NO2 -, and the off-gas sparging of the PB-DBD for the production of NO3 -.

  20. Universality in fast quantum quenches

    CERN Document Server

    Das, Sumit R; Myers, Robert C

    2014-01-01

    We expand on the investigation of the universal scaling properties in the early time behaviour of fast but smooth quantum quenches in a general $d$-dimensional conformal field theory deformed by a relevant operator of dimension $\\Delta$ with a time-dependent coupling. The quench consists of changing the coupling from an initial constant value $\\lambda_1$ by an amount of the order of $\\delta \\lambda$ to some other final value $\\lambda_2$, over a time scale $\\delta t$. In the fast quench limit where $\\delta t$ is smaller than all other length scales in the problem, $ \\delta t \\ll \\lambda_1^{1/(\\Delta-d)}, \\lambda_2^{1/(\\Delta-d)}, \\delta \\lambda^{1/(\\Delta-d)}$, the energy (density) injected into the system scales as $\\delta{\\cal E} \\sim (\\delta \\lambda)^2 (\\delta t)^{d-2\\Delta}$. Similarly, the change in the expectation value of the quenched operator at times earlier than the endpoint of the quench scales as $\\langle {\\cal O}_\\Delta\\rangle \\sim \\delta \\lambda\\, (\\delta t)^{d-2\\Delta}$, with further logarithmic...

  1. Chiral Logs in Quenched QCD

    CERN Document Server

    Dong, S J; Horváth, I; Lee, F X; Liu, K F; Mathur, N; Zhang, J B

    2003-01-01

    The quenched chiral logs are examined on a $16^3 \\times 28$ lattice with Iwasaki gauge action and overlap fermions. The pion decay constant $f_{\\pi}$ is used to set the lattice spacing, $a = 0.200(3)$ fm. With pion mass as low as $\\sim 180 {\\rm MeV}$, we see the quenched chiral logs clearly in $m_{\\pi}^2/m$ and $f_P$, the pseudoscalar decay constant. We analyze the data to determine how low the pion mass needs to be in order for the quenched one-loop chiral perturbation theory ($\\chi$PT) to apply. With the constrained curve fitting, we are able to extract the quenched chiral log parameter $\\delta$ together with the chiral cutoff $\\Lambda_{\\chi}$ and other parameters. Only for $m_{\\pi} \\leq 300 {\\rm MeV}$ do we obtain a consistent and stable fit with a constant $\\delta$ which we determine to be 0.23(2). By comparing to the $12^3 \\times 28$ lattice, we estimate the finite volume effect to be about 1.8% for the smallest pion mass. We also study the quenched non-analytic terms in the nucleon and the $\\rho$ masses...

  2. Quenching in coupled adiabatic coils

    Energy Technology Data Exchange (ETDEWEB)

    Williams, J.E.C.

    1985-03-01

    The prediction of the effects of a quench on stress and temperature is an important aspect of the design of superconducting magnets. Of particular interest, and the exclusive topic of this study, is the prediction of the effects of quenching in coupled adiabatic coils, such as the multi-section windings of a high field NMR spectrometer magnet. The predictive methods used here are based on the measurement of the time of propagation of quench between turns. From this measurement an approximate algorithum for the propagation time is used in a code which solves the linear differential equations for the coil currents and calculates the movement of normal zone boundaries and hence the associated winding resistance.

  3. Red wine prevents the postprandial increase in plasma cholesterol oxidation products: a pilot study.

    Science.gov (United States)

    Natella, F; Macone, A; Ramberti, A; Forte, M; Mattivi, F; Matarese, R M; Scaccini, C

    2011-06-28

    Moderate wine consumption has been shown to lower cardiovascular risk. One of the mechanisms could involve the control of postprandial hyperlipaemia, a well-defined risk factor for atherosclerosis, reasonably by reducing the absorption of lipid oxidised species from the meal. The objective of the present study was to investigate whether wine consumption with the meal is able to reduce the postprandial increase in plasma lipid hydroperoxides and cholesterol oxidation products, in human subjects. In two different study sessions, twelve healthy volunteers consumed the same test meal rich in oxidised and oxidisable lipids (a double cheeseburger), with 300 ml of water (control) or with 300 ml of red wine (wine). The postprandial plasma concentration of cholesterol oxidation products was measured by GC-MS. The control meal induced a significant increase in the plasma concentration of lipid hydroperoxides and of two cholesterol oxidation products, 7-β-hydroxycholesterol and 7-ketocholesterol. The postprandial increase in lipid hydroperoxides and cholesterol oxidation products was fully prevented by wine when consumed with the meal. In conclusion, the present study provides evidence that consumption of wine with the meal could prevent the postprandial increase in plasma cholesterol oxidation products.

  4. Plasma chemical production of stable isotopes of germanium from its fluorides

    Science.gov (United States)

    Kornev, Roman; Sennikov, Peter

    2016-08-01

    The reduction process of 72GeF4 in hydrogen plasma of RF-discharge (13.56 MHz) was experimentally investigated. It was found that 72Ge, polyfluorogermanes and gaseous HF were the main products of conversion. The behavior of the main electroactive impurities and of metal impurities in the process of hydrogen reduction of 72GeF4 was considered. Based on the data of emission spectroscopy of chemically active plasma, assumptions were made about the main plasma-chemical reactions responsible for the process of hydrogen reduction of 72GeF4. A single crystal of n-type with concentration of charge carriers of Czochralski method after the process of zone recrystallization of 72Ge. Contribution to the topical issue "6th Central European Symposium on Plasma Chemistry (CESPC-6)", edited by Nicolas Gherardi, Ester Marotta and Cristina Paradisi

  5. Effect of Wall Material on H– Production in a Plasma Sputter-Type Ion Source

    Directory of Open Access Journals (Sweden)

    Y. D. M. Ponce

    2004-12-01

    Full Text Available The effect of wall material on negative hydrogen ion (H– production was investigated in a multicusp plasma sputter-type ion source (PSTIS. Steady-state cesium-seeded hydrogen plasma was generated by a tungsten filament, while H– was produced through surface production using a molybdenum sputter target. Plasma parameters and H– yields were determined from Langmuir probe and Faraday cup measurements, respectively. At an input hydrogen pressure of 1.2 mTorr and optimum plasma discharge parameters Vd = –90 V and Id = –2.25 A, the plasma parameters ne was highest and T–e was lowest as determined from Langmuir probe measurements. At these conditions, aluminum generates the highest ion current density of 0.01697 mA/cm2, which is 64% more than the 0.01085 mA/cm2 that stainless steel produces. The yield of copper, meanwhile, falls between the two materials at 0.01164 mA/cm2. The beam is maximum at Vt = –125 V. Focusing is achieved at VL = –70 V for stainless steel, Vt = –60 V for aluminum, and Vt = –50 V for copper. The results demonstrate that proper selection of wall material can greatly enhance the H– production of the PSTIS.

  6. The role of plasma adenosine deaminase in chemoattractant-stimulated oxygen radical production in neutrophils.

    Science.gov (United States)

    Kälvegren, Hanna; Fridfeldt, Jonna; Bengtsson, Torbjörn

    2010-06-01

    Adenosine deaminase (ADA) has a role in many immunity mediated disorders, such as asthma, tuberculosis and coronary artery disease. This study aims to investigate the ability of plasma ADA to modulate reactive oxygen species (ROS) production in neutrophils, and examine the involvement of adenosine and the cyclic AMP signaling pathway in this process. Neutrophils were stimulated, in the absence or presence of plasma, with the chemotactic peptide fMLP (formyl-methionyl-leucyl-phenylalanine), and the ROS production was determined with luminol-enhanced chemiluminescence. Activity of ADA was measured spectrophotometrically. Plasma dose-dependently amplified the ROS generation in fMLP-stimulated neutrophils. In parallel, incubation of neutrophils in plasma elevated the total ADA-activity approximately 10 times from 1.3 U/ml to 12 U/ml. Inhibition of ADA, or type IV phosphodiesterases, significantly lowered the plasma-mediated ROS production. Furthermore, the high-affinity adenosine A(1) receptor antagonists DPCPX and 8-phenyltheophylline markedly inhibited the plasma-induced respiratory burst in neutrophils, suggesting an A(1) receptor-mediated mechanism. This study suggests that plasma ADA amplifies the release of toxic oxygen radicals from neutrophils through a downregulation of the inhibitory adenosine/cAMP-system and an enhanced activation of the stimulatory adenosine A(1)-receptor. This mechanism has probably a crucial role in regulating neutrophil function and in the defence against microbial infections. However, a sustained neutrophil activation could also contribute to inflammatory disorders such as atherosclerosis. 2010 Elsevier GmbH. All rights reserved.

  7. Pathogen safety of plasma-derived products - Haemate P/Humate-P.

    Science.gov (United States)

    Gröner, A

    2008-11-01

    Plasma-derived factor VIII (FVIII) and von Willebrand Factor (VWF)/FVIII concentrates have been successfully used to treat haemophilia since the late 1960s. These products are derived from pools of plasma donations that may contain viral contaminants - including hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) - and may therefore present a transmission risk to recipients. To ensure the safety of Haemate P/Humate-P, a plasma-derived VWF/FVIII concentrate, donors of plasma are carefully selected and all donations are screened for viral antigens (HBV), virus-specific antibodies (HIV-1/2, HCV) and genomic material [hepatitis A virus, HBV, HCV, HIV-1 and high titres of human parvovirus B19 (B19V)]. As a quality control measure, plasma pools for fractionation are only released for further processing when non-reactivity has been demonstrated in serological and genome amplification assays. The manufacturing process for plasma-derived products, especially the fundamental procedure of pasteurization, is effective in inactivating and/or removing a wide variety of viruses that may potentially be present despite the screening process. This has been demonstrated in virus validation studies using a range of different viruses. New emerging infectious agents, including prions, which potentially pose a threat to recipients of plasma derivatives, are also the subject of safety evaluations. The multiple precautionary measures that are inherent in the overall production process of Haemate P/Humate-P have resulted in an excellent safety record, documented during 25 years of clinical use, and will help to maintain the high safety margin in the future.

  8. Thermal dilepton rates from quenched lattice QCD

    CERN Document Server

    Ding, H -T; Kaczmarek, O; Karsch, F; Laermann, E; Mukherjee, S; Müller, M; Soeldner, W

    2013-01-01

    We present new lattice results on the continuum extrapolation of the vector current correlation function. Lattice calculations have been carried out in the deconfined phase at a temperature of 1.1 Tc, extending our previous results at 1.45 Tc, utilizing quenched non-perturbatively clover-improved Wilson fermions and light quark masses. A systematic analysis on multiple lattice spacings allows to perform the continuum limit of the correlation function and to extract spectral properties in the continuum limit. Our current analysis suggests the results for the electrical conductivity are proportional to the temperature and the thermal dilepton rates in the quark gluon plasma are comparable for both temperatures. Preliminary results of the continuum extrapolated correlation function at finite momenta, which relates to thermal photon rates, are also presented.

  9. Hard Photon production from unsaturated quark gluon plasma at two loop level

    CERN Document Server

    Dutta, D; Mohanty, A K; Kumar, K; Choudhury, R K

    2002-01-01

    The hard photon productions from bremsstrahlung and annihilation with scattering that arise at two loop level are estimated from a chemically non-equilibrated quark gluon plasma using the frame work of thermal field theory. Although, the rate of photon production is suppressed due to unsaturated phase space, the above suppression is relatively smaller than expected due to an additional collinear enhancement (arise due to decrease in thermal quark mass) as compared to it's equilibrium counterpart. Interestingly, unlike the one loop case, the reduction in the two loop processes are found to be independent of gluon chemical poential, but strongly depends on quark fugacity. It is also found that, since the phase space suppression is highest for annihilation with scattering, the photon production is entirely dominated by bremsstrahlung mechanism at all energies. This is to be contrasted with the case of the equilibrated plasma where annihilation with scattering dominates the photon production particularly at highe...

  10. Correlation of H/sup -/ production and the work function of a surface in a hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Wada, M.

    1983-03-01

    Surface-plasma negative hydrogen ion sources are being developed as possible parts for future neutral beam systems. In these ion sources, negative hydrogen ions (H/sup -/) are produced at low work function metal surfaces immersed in hydrogen plasmas. To investigate the correlation between the work function and the H/sup -/ production at the surface with a condition similar to the one in the actual plasma ion source, these two parameters were simultaneously measured in the hydrogen plasma environment.

  11. Strangeness production as a signal for quark-gluon plasma formation in high energy particle collisions

    Energy Technology Data Exchange (ETDEWEB)

    Redlich, K.

    1985-04-01

    Strangeness production in hot nuclear matter in the non-interacting gas approximation with an Usub(B)(1)xUsub(S)(1) internal symmetry group is discussed. It is argued that the stangeness abundancy ratio in the quark-gluon plasma as compared to the hadron gas strongly depends on under which thermodynamical circumstances it has been computed.

  12. Micro-scale Plasma Arc Gasification for Waste Treatment and Energy Production Project

    Science.gov (United States)

    Caraccio, Anne

    2015-01-01

    As NASA continues to develop technology for spaceflight beyond low earth orbit, we must develop the right systems for sustaining human life on a long duration or planetary mission. Plasma arc gasification (PAG) is an energy efficient mechanism of waste management for power generation and synthetic gas(syngas) production.

  13. A nonlabeled method to evaluate cortisol production rate by modeling plasma CBG-free cortisol disposition

    OpenAIRE

    Picard-Hagen, Nicole; Gayrard-Troy, Véronique,; Alvinerie, Michel; Smeyers, Hélène; Ricou, Raphael; Bousquet-Mélou, Alain; Toutain, Pierre-Louis

    2001-01-01

    This study aimed to develop a nonlabeled method for the measurement of cortisol production rate to evaluate adrenal function. The cortisol production rate determination requires that of cortisol clearance, which is not a parameter but a variable resulting from the saturable binding of cortisol to corticosteroid-binding globulin (CBG). Our method is based on evaluation of the plasma clearance of the CBG-free cortisol fraction. This parameter was evaluated from a pharmacokinetic model of total ...

  14. Bioanalytical Applications of Fluorenscence Quenching.

    Science.gov (United States)

    1986-02-10

    interaction of different cyclodextrin systems with the polynuclear aromatic compound, pyrene.(7 ) There are other cases where the Stern-Volmer plot deviates... encapsulated in lecithin liposomes. In this manner the fluorescence is self-quenched. When the liposomes are disrupted, the dye is released and

  15. Entropy production for an interacting quark-gluon plasma

    CERN Document Server

    Mattiello, Stefano

    2011-01-01

    We investigate the entropy production within dissipative hydrodynamics in the Israel-Stewart (IS) and Navier-Stokes theory (NS) for relativistic heavy ion physics applications. In particular we focus on the initial condition in a 0+1D Bjorken scenario, appropriate for the early longitudinal expansion stage of the collision. Going beyond the standard simplification of a massless ideal gas we consider a realistic equation of state consistently derived within a virial expansion. The EoS used is well in line with recent three-flavor QCD lattice data for the pressure, speed of sound, and interaction measure at nonzero temperature and vanishing chemical potential ($\\mu_{\\rm q} = 0$). The shear viscosity has been consistently calculated within this formalism using a kinetic approach in the ultra-relativistic regime with an explicit and systematic evaluation of the transport cross section as function of temperature. We investigate the influence of the viscosity and the initial condition, i.e. formation time, initial ...

  16. How to quench a galaxy

    Science.gov (United States)

    Pontzen, Andrew; Tremmel, Michael; Roth, Nina; Peiris, Hiranya V.; Saintonge, Amélie; Volonteri, Marta; Quinn, Tom; Governato, Fabio

    2017-02-01

    We show how the interplay between active galactic nuclei (AGNs) and merger history determines whether a galaxy quenches star formation (SF) at high redshift. We first simulate, in a full cosmological context, a galaxy of total dynamical mass Mvir = 1012 M⊙ at z = 2. Then we systematically alter the accretion history of the galaxy by minimally changing the linear overdensity in the initial conditions. This `genetic modification' approach allows the generation of three sets of Λ CDM initial conditions leading to maximum merger ratios of 1:10, 1:5 and 2:3, respectively. The changes leave the final halo mass, large-scale structure and local environment unchanged, providing a controlled numerical experiment. Interaction between the AGN physics and mergers in the three cases leads, respectively, to a star-forming, temporarily quenched and permanently quenched galaxy. However, the differences do not primarily lie in the black hole accretion rates, but in the kinetic effects of the merger: the galaxy is resilient against AGN feedback unless its gaseous disc is first disrupted. Typical accretion rates are comparable in the three cases, falling below 0.1 M⊙ yr-1, equivalent to around 2 per cent of the Eddington rate or 10-3 times the pre-quenching star formation rate, in agreement with observations. This low level of black hole accretion can be sustained even when there is insufficient dense cold gas for SF. Conversely, supernova feedback is too distributed to generate outflows in high-mass systems, and cannot maintain quenching over periods longer than the halo gas cooling time.

  17. 100% N2 atmospheric-pressure microwave-line-plasma production with a modified waveguide structure

    Science.gov (United States)

    Suzuki, Haruka; Tamura, Yuto; Itoh, Hitoshi; Sekine, Makoto; Hori, Masaru; Toyoda, Hirotaka

    2016-09-01

    Large-scale atmospheric pressure (AP) plasmas have been given much attention because of its high cost benefit and a variety of possibilities for industrial applications. Microwave discharge plasma using slot antenna is attractive due to its ability of high-density and stable plasma production, and we have developed a long-scale AP microwave plasma (AP microwave line plasma: AP-MLP) source using loop-structured waveguide and travelling wave and have reported spatially-uniform AP-MLP of 40 cm in length using Ar or He gas discharge. However, rare gas discharge is not always suitable for industrial applications because usage of large volume rare gas degrades the AP cost benefit. Furthermore, many industrial applications require chemically-reactive species and the AP-MLP using molecular gas will drastically increase the applications of the AP-MLP. In this study, we demonstrate 100% N2 discharge of the AP-MLP with a modified waveguide structure. Cross-sectional structure of the waveguide is improved to enhance the microwave electric field in the slot. 100% N2 plasma of 15 cm-long is successfully produced using CW microwave power of 2 kW. Low gas temperature of 1000 K is confirmed by optical emission spectroscopy, suggesting applications of the AP-MLP to low temperature processes. Part of this work is supported by JSPS KAKENHI Grant Number 25286079.

  18. Plasma fibrinogen degradation products in betel nut chewers - with and without oral submucous fibrosis

    Directory of Open Access Journals (Sweden)

    G Kiran

    2013-01-01

    Full Text Available Context: Oral submucous fibrosis (OSMF has a multifactorial etiology. Recent studies have shown that there is an increased level of fibrinogen degradation products (FDP in plasma of OSMF patients suggesting its possible role in etiopathogenesis of OSMF. Aims: To detect the presence of FDP in the plasma of betel nut chewers with and without OSMF and in normal subjects without any habits, to correlate these levels with respect to the clinical and histological grading of OSMF and whether it can be used as a nonsurgical diagnostic aid in detection of suspected OSMF cases. Materials and Methods: Study comprised of 35 cases of betel nut chewers with OSMF, 10 patients with betel nut chewing habit but having apparently normal oral mucosa, and 10 normal patients without any habits. The patients were evaluated for plasma FDP levels. Results: All the betel nut chewers with OSMF showed the presence of plasma FDP. However, controls and subjects with habit, but without OSMF did not show FDP in the plasma. Spearman′s rank correlation was used to find the association between the clinical and histological grades and it was not statistically significant (P = 0.910 and the correlation being 0.020. Conclusion: Since only those patients with OSMF have showed the presence of FDP in plasma, we suggest that our test can be utilized as a nonsurgical diagnostic aid in suspected OSMF patients.

  19. Products of DNA, protein and lipid oxidative damage in relation to vitamin C plasma concentration.

    Science.gov (United States)

    Krajcovicová-Kudlácková, M; Dusinská, M; Valachovicová, M; Blazícek, P; Pauková, V

    2006-01-01

    Oxidative stress plays an important role in the pathogenesis of numerous chronic age-related free radical-induced diseases. Improved antioxidant status minimizes oxidative damage to DNA, proteins, lipids and other biomolecules. Diet-derived antioxidants such as vitamin C, vitamin E, carotenoids and related plant pigments are important in antioxidative defense and maintaining health. The results of long-term epidemiological and clinical studies suggest that protective vitamin C plasma concentration for minimum risk of free radical disease is higher than 50 micromol/l. Products of oxidative damage to DNA (DNA strand breaks with oxidized purines and pyrimidines), proteins (carbonyls) and lipids (conjugated dienes of fatty acids, malondialdehyde) were estimated in a group of apparently healthy adult non-smoking population in dependence on different vitamin C plasma concentrations. Under conditions of protective plasma vitamin C concentrations (>50 micromol/l) significantly lower values of DNA, protein and lipid oxidative damage were found in comparison with the vitamin C-deficient group (fruit and vegetable consumption (leading to higher vitamin C intake and higher vitamin C plasma concentrations) on oxidation of DNA, proteins and lipids is also expressed by an inverse significant correlation between plasma vitamin C and products of oxidative damage. The results suggest an important role of higher and frequent consumption of protective food (fruit, vegetables, vegetable oils, nuts, seeds and cereal grains) in prevention of free radical disease.

  20. Dynamical Outcomes of Quenching: Reflections on a Conical Intersection

    Science.gov (United States)

    Lehman, Julia H.; Lester, Marsha I.

    2014-04-01

    This review focuses on experimental studies of the dynamical outcomes following collisional quenching of electronically excited OH A2Σ+ radicals by molecular partners. The experimental observables include the branching between reactive and nonreactive decay channels, kinetic energy release, and quantum state distributions of the products. Complementary theoretical investigations reveal regions of strong nonadiabatic coupling, known as conical intersections, which facilitate the quenching process. The dynamical outcomes observed experimentally are connected to the local forces and geometric properties of the nuclei in the conical intersection region. Dynamical calculations for the benchmark OH-H2 system are in good accord with experimental observations, demonstrating that the outcomes reflect the strong coupling in the conical intersection region as the system evolves from the excited electronic state to quenched products.

  1. Inactivation of Zika virus by solvent/detergent treatment of human plasma and other plasma-derived products and pasteurization of human serum albumin.

    Science.gov (United States)

    Kühnel, Denis; Müller, Sebastian; Pichotta, Alexander; Radomski, Kai Uwe; Volk, Andreas; Schmidt, Torben

    2017-03-01

    In 2016 the World Health Organization declared the mosquito-borne Zika virus (ZIKV) a "public health emergency of international concern." ZIKV is a blood-borne pathogen, which therefore causes concerns regarding the safety of human plasma-derived products due to potential contamination of the blood supply. This study investigated the effectiveness of viral inactivation steps used during the routine manufacturing of various plasma-derived products to reduce ZIKV infectivity. Human plasma and intermediates from the production of various plasma-derived products were spiked with ZIKV and subjected to virus inactivation using the identical techniques (either solvent/detergent [S/D] treatment or pasteurization) and conditions used for the actual production of the respective products. Samples were taken and the viral loads measured before and after inactivation. After S/D treatment of spiked intermediates of the plasma-derived products Octaplas(LG), Octagam, and Octanate, the viral loads were below the limit of detection in all cases. The mean log reduction factor (LRF) was at least 6.78 log for Octaplas(LG), at least 7.00 log for Octagam, and at least 6.18 log for Octanate after 60, 240, and 480 minutes of S/D treatment, respectively. For 25% human serum albumin (HSA), the mean LRF for ZIKV was at least 7.48 log after pasteurization at 60°C for 120 minutes. These results demonstrate that the commonly used virus inactivation processes utilized during the production of human plasma and plasma-derived products, namely, S/D treatment or pasteurization, are effective for inactivation of ZIKV. © 2016 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  2. Quench Simulation Studies: Program documentation of SPQR

    CERN Document Server

    Sonnemann, F

    2001-01-01

    Quench experiments are being performed on prototypes of the superconducting magnets and busbars to determine the adequate design and protection. Many tests can only be understood correctly with the help of quench simulations that model the thermo-hydraulic and electrodynamic processes during a quench. In some cases simulations are the only method to scale the experimental results of prototype measurements to match the situation of quenching superconducting elements in the LHC. This note introduces the theoretical quench model and the use of the simulation program SPQR (Simulation Program for Quench Research), which has been developed to compute the quench process in superconducting magnets and busbars. The model approximates the heat balance equation with the finite difference method including the temperature dependence of the material parameters. SPQR allows the simulation of longitudinal quench propagation along a superconducting cable, the transverse propagation between adjacent conductors, heat transfer i...

  3. Enhanced photon emission and pair production in laser-irradiated plasmas

    Science.gov (United States)

    Wan, Feng; Lv, Chong; Jia, Moran; Xie, Baisong

    2017-07-01

    Enhanced photon emission and pair production due to heavy ion mass in the interaction of an ultraintense laser with overdense plasmas is explored by particle-in-cell simulation. It is found that plasmas with heavier ion mass can excite a higher and broader electrostatic field, which causes the enhancement of backward photon emission. The pair yields are then enhanced due to the increase of backwards photons colliding with the incoming laser pulse. By examining the density evolution and angle distribution of each particle species, the origin of pair yield enhancement is clarified.

  4. Photon production from quark gluon plasma at finite baryon density

    Indian Academy of Sciences (India)

    D Dutta; S V S Sastry; A K Mohanty; K Kumar; R K Choudhury

    2003-05-01

    The photon yield from a baryon-rich quark gluon plasma (QGP) at SPS energy has been estimated. In the QGP phase, rate of photon production is evaluated up to two-loop level. In the hadron phase, dominant contribution from , , mesons has been considered. The evolution of the plasma has been studied with appropriate equation of state in both QGP and hadron phase for a baryon-rich system. At SPS energy, the total photon yield is found to increase marginally in the presence of baryon density.

  5. Perioperative plasma concentrations of stable nitric oxide products are predictive of cognitive dysfunction after laparoscopic cholecystectomy.

    LENUS (Irish Health Repository)

    Iohom, G

    2012-02-03

    In this study our objectives were to determine the incidence of postoperative cognitive dysfunction (POCD) after laparoscopic cholecystectomy under sevoflurane anesthesia in patients aged >40 and <85 yr and to examine the associations between plasma concentrations of i) S-100beta protein and ii) stable nitric oxide (NO) products and POCD in this clinical setting. Neuropsychological tests were performed on 42 ASA physical status I-II patients the day before, and 4 days and 6 wk after surgery. Patient spouses (n = 13) were studied as controls. Cognitive dysfunction was defined as deficit in one or more cognitive domain(s). Serial measurements of serum concentrations of S-100beta protein and plasma concentrations of stable NO products (nitrate\\/nitrite, NOx) were performed perioperatively. Four days after surgery, new cognitive deficit was present in 16 (40%) patients and in 1 (7%) control subject (P = 0.01). Six weeks postoperatively, new cognitive deficit was present in 21 (53%) patients and 3 (23%) control subjects (P = 0.03). Compared with the "no deficit" group, patients who demonstrated a new cognitive deficit 4 days postoperatively had larger plasma NOx at each perioperative time point (P < 0.05 for each time point). Serum S-100beta protein concentrations were similar in the 2 groups. In conclusion, preoperative (and postoperative) plasma concentrations of stable NO products (but not S-100beta) are associated with early POCD. The former represents a potential biochemical predictor of POCD.

  6. Plasmas for environmental issues: from hydrogen production to 2D materials assembly

    Science.gov (United States)

    Tatarova, E.; Bundaleska, N.; Sarrette, J. Ph; Ferreira, C. M.

    2014-12-01

    It is well recognized at present that the unique, high energy density plasma environment provides suitable conditions to dissociate/atomize molecules in remediation systems, to convert waste and biomass into sustainable energy sources, to purify water, to assemble nanostructures, etc. The remarkable plasma potential is based on its ability to supply simultaneously high fluxes of charged particles, chemically active molecules, radicals (e.g. O, H, OH), heat, highly energetic photons (UV and extreme UV radiation), and strong electric fields in intrinsic sheath domains. Due to this complexity, low-temperature plasma science and engineering is a huge, highly interdisciplinary field that spans many research disciplines and applications across many areas of our daily life and industrial activities. For this reason, this review deals only with some selected aspects of low-temperature plasma applications for a clean and sustainable environment. It is not intended to be a comprehensive survey, but just to highlight some important works and achievements in specific areas. The selected issues demonstrate the diversity of plasma-based applications associated with clean and sustainable ambiance and also show the unity of the underlying science. Fundamental plasma phenomena/processes/features are the common fibers that pass across all these areas and unify all these applications. Browsing through different topics, we try to emphasize these phenomena/processes/features and their uniqueness in an attempt to build a general overview. The presented survey of recently published works demonstrates that plasma processes show a significant potential as a solution for waste/biomass-to-energy recovery problems. The reforming technologies based on non-thermal plasma treatment of hydrocarbons show promising prospects for the production of hydrogen as a future clean energy carrier. It is also shown that plasmas can provide numerous agents that influence biological activity. The simultaneous

  7. Experimental Production of Non-Quenched and Tempered Steel for Grade 10.9 Fasteners%10.9级紧固件用非调质钢试制

    Institute of Scientific and Technical Information of China (English)

    曹杰; 阎军; 孙维; 刘雅政; 章静; 于同仁

    2012-01-01

    为开发高强度紧固件用非调质钢,在高速线材轧机上进行了试验轧制,并对试制产品的组织性能进行了检测。结果表明,在给定工艺条件下钢的组织基本上为粒状贝氏体组织,抗拉强度为897.5MPa,伸长率为21.8%。热轧材拉拔减面后达到或超过10.9级紧固件的力学性能要求。当拉拔量为25.0%时,可承受59.3%的压缩变形不开裂。%In order to develop a non-quenched and tempered steel for high strength fasteners, experimental production was carried out on a high-speed wire rod mill. The microstrueture and properties of the rolling products was tested. The microstrueture of the steel is basically granular bainite under the given technology, the tensile strength and elongation ratio of the steel are respectively 897.5 MPa and 21.8%. After drawing reduction, the steel can meet or exceed the mechanical requirement of grade 10.9 fasteners. When the drawing reduction is 25.0%, the steel can bear the compression of 59.3% without cracking.

  8. Electromagnetic ion-cyclotron instability in a dusty plasma with product-bi-kappa distributions for the plasma particles

    CERN Document Server

    Santos, Michel S dos; Gaelzer, Rudi

    2016-01-01

    We study the dispersion relation for parallel propagating ion-cyclotron (IC) waves in a dusty plasma, considering that ions and electrons may be represented by product-bi-kappa (PBK) velocity distributions. The results obtained by numerical solution of the dispersion relation, in a case with isotropic Maxwellian distributions for electrons and PBK distribution for ions, show the occurrence of the electromagnetic ion-cyclotron instability (EMIC), and show that the decrease in the kappa indexes of the PBK ion distribution leads to significant increase of the instability, in magnitude of the growth rates and in range in wavenumber space. On the other hand, for anisotropic Maxwellian distribution for ions and PBK distribution for electrons, the decrease of the kappa index in the PBK electron distribution contributes to reduce the EMIC instability, but the reduction effect is much less pronounced than that obtained with the same combination of distributions in the case of the ion-firehose instability, shown in a r...

  9. Optimization simulation of thermal plasma reactor for acetylene production from coal

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J.; Yang, Y.; Bao, W.; Zhang, Y.; Kie, K. [Taiyuan University of Technology, Taiyuan (China)

    2007-07-01

    A heat-flow field mathematical model based on the computational; fluid dynamics (CFD) technique was developed for a thermal plasma reactor in order to optimize the reactor structure and operation conditions for the direct production of acetylene from coal. The simulation of the thermal plasma reactor with single inlet, double inlet and double inlet with protective gas was given; simulations of the heat-flow coupling field were carried out by using the method of Incomplete Cholesky Conjugate Gradient (ICCG). The optimization simulation results show that the load of the thermal plasma reactor with double inlet is increased, and the reactor wall surface coke is depressed. The anticoking effect is best under the gas flow rate of 50 m/s. 4 refs., 4 figs.

  10. Development and evaluation of magnesium oxide-based ceramics for chamber parts in mass-production plasma etching equipment

    Science.gov (United States)

    Kasashima, Yuji; Tsutsumi, Kota; Mitomi, Shinzo; Uesugi, Fumihiko

    2017-06-01

    In mass-production plasma etching equipment, the corrosion of ceramic chamber parts reduces the production yield of LSI and overall equipment effectiveness (OEE) owing to contamination, short useful life, and particle generation. Novel ceramics that can improve the production yield and OEE are highly required. We develop magnesium oxide (MgO)-based ceramics and evaluate them under mass-production plasma etching conditions. The results of this study indicate that the developed MgO-based ceramics with high mechanical properties and low electric resistivity have a higher resistance to corrosion in plasma etching using CF4 gas than Si and conventional ceramic materials such as aluminum oxide and yttrium oxide.

  11. Quenched Reinforcement Exposed to Fire

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    2006-01-01

    Idealized data are derived for the tensile strength of quenched and tempered prestressing steel and of quenched and self-tempered reinforcing bars for fire safety design. 0.2% stresses are derived as a function of the maximum temperature and in addition, 2.0% stresses are provided. A strain of 2.......0% is seldom found in “slack” (not prestressed) reinforcement, but 2.0% stresses might be relevant for reinforcement in T shaped cross sections and for prestressed structures, where large strains can be applied. All data are provided in a “HOT” condition during a fire and in a “COLD” condition after a fire....... The COLD condition is relevant for analyses of residual load bearing capacity of a structure after a fire exposure. It is also relevant for analyses of concrete structures exposed to fully developed fire courses. The reason is that compression zones of concrete are always the weakest in the cooling phase...

  12. Holographic quenches and anomalous transport

    CERN Document Server

    Ammon, Martin; Jimenez-Alba, Amadeo; Macedo, Rodrigo P; Melgar, Luis

    2016-01-01

    We study the response of the chiral magnetic effect due to continuous quenches induced by time dependent electric fields within holography. Concretely, we consider a holographic model with dual chiral anomaly and compute the electric current parallel to a constant, homogeneous magnetic field and a time dependent electric field in the probe approximation. We explicitly solve the PDEs by means of pseudospectral methods in spatial and time directions and study the transition to an universal "fast" quench response. Moreover, we compute the amplitudes, i.e.,~residues of the quasi normal modes, by solving the (ODE) Laplace transformed equations. We investigate the possibility of considering the asymptotic growth rate of the amplitudes as a well defined notion of initial time scale for linearized systems. Finally, we highlight the existence of Landau level resonances in the electrical conductivity parallel to a magnetic field at finite frequency and show explicitly that these only appear in presence of the anomaly. ...

  13. Quench cooling under reduced gravity

    CERN Document Server

    Chatain, D; Nikolayev, V S; Beysens, D

    2013-01-01

    We report the quench cooling experiments performed with liquid O2 under different levels of gravity simulated with the magnetic gravity compensation. A copper disk is quenched from 270K to 90K. It is found that the cooling time in microgravity is very long in comparison with any other gravity level. This phenomenon is explained by the isolation effect of the gas surrounding the disk. The liquid subcooling is shown to drastically improuve the heat exchange thus reducing the cooling time (about 20 times). The effect of subcooling on the heat transfer is analyzed at different gravity levels. It is shown that such type of experiments cannot be used for the analysis of the critical heat flux (CHF) of the boiling crisis. The minimum heat flux (MHF) of boiling is analyzed instead.

  14. Quenched Reinforcement Exposed to Fire

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    2006-01-01

    Idealized data are derived for the tensile strength of quenched and tempered prestressing steel and of quenched and self-tempered reinforcing bars for fire safety design. 0.2% stresses are derived as a function of the maximum temperature and in addition, 2.0% stresses are provided. A strain of 2.......0% is seldom found in “slack” (not prestressed) reinforcement, but 2.0% stresses might be relevant for reinforcement in T shaped cross sections and for prestressed structures, where large strains can be applied. All data are provided in a “HOT” condition during a fire and in a “COLD” condition after a fire....... The COLD condition is relevant for analyses of residual load bearing capacity of a structure after a fire exposure. It is also relevant for analyses of concrete structures exposed to fully developed fire courses. The reason is that compression zones of concrete are always the weakest in the cooling phase...

  15. TASK 2: QUENCH ZONE SIMULATION

    Energy Technology Data Exchange (ETDEWEB)

    Fusselman, Steve

    2015-09-30

    Aerojet Rocketdyne (AR) has developed an innovative gasifier concept incorporating advanced technologies in ultra-dense phase dry feed system, rapid mix injector, and advanced component cooling to significantly improve gasifier performance, life, and cost compared to commercially available state-of-the-art systems. A key feature of the AR gasifier design is the transition from the gasifier outlet into the quench zone, where the raw syngas is cooled to ~ 400°C by injection and vaporization of atomized water. Earlier pilot plant testing revealed a propensity for the original gasifier outlet design to accumulate slag in the outlet, leading to erratic syngas flow from the outlet. Subsequent design modifications successfully resolved this issue in the pilot plant gasifier. In order to gain greater insight into the physical phenomena occurring within this zone, AR developed a cold flow simulation apparatus with Coanda Research & Development with a high degree of similitude to hot fire conditions with the pilot scale gasifier design, and capable of accommodating a scaled-down quench zone for a demonstration-scale gasifier. The objective of this task was to validate similitude of the cold flow simulation model by comparison of pilot-scale outlet design performance, and to assess demonstration scale gasifier design feasibility from testing of a scaled-down outlet design. Test results did exhibit a strong correspondence with the two pilot scale outlet designs, indicating credible similitude for the cold flow simulation device. Testing of the scaled-down outlet revealed important considerations in the design and operation of the demonstration scale gasifier, in particular pertaining to the relative momentum between the downcoming raw syngas and the sprayed quench water and associated impacts on flow patterns within the quench zone. This report describes key findings from the test program, including assessment of pilot plant configuration simulations relative to actual

  16. Jet-quenching and correlations

    Indian Academy of Sciences (India)

    Fuqiang Wang

    2015-05-01

    This article reviews recent advances in our understanding of the experimental aspects of jet-quenching and correlations in relativistic heavy-ion collisions at RHIC and LHC. Emphasis is put on correlation measurements, namely jet-like correlations with anisotropic flow subtraction in heavy-ion collisions and long-range pseudorapidity correlations in small systems. Future path on correlation studies is envisioned which may elucidate jet–medium interactions and the properties of the hot dense medium in QCD.

  17. First Production of C60 Nanoparticle Plasma Jet for Study of Disruption Mitigation for ITER

    Science.gov (United States)

    Bogatu, I. N.; Thompson, J. R.; Galkin, S. A.; Kim, J. S.; Brockington, S.; Case, A.; Messer, S. J.; Witherspoon, F. D.

    2012-10-01

    Unique fast response and large mass-velocity delivery of nanoparticle plasma jets (NPPJs) provide a novel application for ITER disruption mitigation, runaway electrons diagnostics and deep fueling. NPPJs carry a much larger mass than usual gases. An electromagnetic plasma gun provides a very high injection velocity (many km/s). NPPJ has much higher ram pressure than any standard gas injection method and penetrates the tokamak confining magnetic field. Assimilation is enhanced due to the NP large surface-to-volume ratio. Radially expanding NPPJs help achieving toroidal uniformity of radiation power. FAR-TECH's NPPJ system was successfully tested: a coaxial plasma gun prototype (˜35 cm length, 96 kJ energy) using a solid state TiH2/C60 pulsed power cartridge injector produced a hyper-velocity (>4 km/s), high-density (>10^23 m-3), C60 plasma jet in ˜0.5 ms, with ˜1-2 ms overall response-delivery time. We present the TiH2/C60 cartridge injector output characterization (˜180 mg of sublimated C60 gas) and first production results of a high momentum C60 plasma jet (˜0.6 g.km/s).

  18. The LHC quench protection system

    CERN Multimedia

    2009-01-01

    The new quench protection system (QPS) has the crucial roles of providing an early warning for any part of the superconducting coils and busbars that develop high resistance, as well as triggering the switch-off of the machine. Over 2000 new detectors will be installed around the LHC to make sure every busbar segment between magnets is monitored and protected. One of the major consolidation activities for the LHC is the addition of two new detectors to the quench protection system. A magnet quench occurs when part of the superconducting cable becomes normally-conducting. When the protection system detects an increased resistance the huge amount of energy stored in the magnet chains is safely extracted and ‘dumped’ into specially designed resistors. In the case of the main dipole chain, the stored energy in a single LHC sector is roughly the same as the kinetic energy of a passenger jet at cruising speed. The first new detector is designed to monitor the superconducting...

  19. How to quench a galaxy

    CERN Document Server

    Pontzen, Andrew; Roth, Nina; Peiris, Hiranya V; Saintonge, Amélie; Volonteri, Marta; Quinn, Tom; Governato, Fabio

    2016-01-01

    We show how the interplay between active galactic nuclei (AGN) and merger history determines whether a galaxy quenches star formation at high redshift. We first simulate, in a full cosmological context, a galaxy of total dynamical mass $10^{12}\\,M_{\\odot}$ at $z=2$. Then we systematically alter the accretion history of the galaxy by minimally changing the linear overdensity in the initial conditions. This "genetic modification" approach allows the generation of three sets of $\\Lambda$CDM initial conditions leading to maximum merger ratios of 1:10, 1:5 and 2:3 respectively. The changes leave the final halo mass, large scale structure and local environment unchanged, providing a controlled numerical experiment. Interaction between the AGN physics and mergers in the three cases lead respectively to a star-forming, temporarily-quenched and permanently-quenched galaxy. However the differences do not primarily lie in the black hole accretion rates, but in the kinetic effects of the merger: the galaxy is resilient a...

  20. Enhancement of H{sup -}/D{sup -} volume production in a double plasma type negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Fukumasa, Osamu; Nishimura, Hideki; Sakiyama, Satoshi [Yamaguchi Univ., Ube (Japan). Faculty of Engineering

    1997-02-01

    H{sup -}/D{sup -} production in a pure volume source has been studied. In our double plasma type negative ion source, both energy and density of fast electrons are well controlled. With the use of this source, the enhancement of H{sup -}/D{sup -} production has been observed. Namely, under the same discharge power, the extracted H{sup -}/D{sup -} current in the double plasma operation is higher than that in the single plasma operation. At the same time, measurements of plasma parameters have been made in the source and the extractor regions for these two cases. (author)

  1. Controlling the nitric and nitrous oxide production of an atmospheric pressure plasma jet

    Science.gov (United States)

    Douat, Claire; Hubner, Simon; Engeln, Richard; Benedikt, Jan

    2016-09-01

    Atmospheric pressure plasma jets are non-thermal plasmas and have the ability to create reactive species. These features make it a very attractive tool for biomedical applications. In this work, we studied NO and N2O production, which are two species having biomedical properties. NO plays a role in the vascularization and in ulcer treatment, while N2O is used as anesthetic and analgesic gas. In this study, the plasma source is similar to the COST Reference Microplasma Jet (µ-APPJ). Helium is used as feed gas with small admixtures of molecular nitrogen and oxygen of below 1%. The absolute densities of NO and N2O were measured in the effluent of an atmospheric pressure RF plasma jet by means of ex-situ quantum-cascade laser absorption spectroscopy via a multi-pass cell in Herriot configuration. We will show that the species' production is dependent on several parameters such as power, flow and oxygen and nitrogen admixture. The NO and N2O densities are strongly dependent on the N2-O2 ratio. Changing this ratio allows for choosing between a NO-rich or a N2O-rich regime.

  2. Determination of trace elements in petroleum products by inductively coupled plasma techniques: A critical review

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez, Raquel [Department of Analytical Chemistry, Nutrition and Food Sciences, P.O. Box 99, 03080, Alicante (Spain); Todolí, José Luis, E-mail: jose.todoli@ua.es [Department of Analytical Chemistry, Nutrition and Food Sciences, P.O. Box 99, 03080, Alicante (Spain); Lienemann, Charles-Philippe [IFP Energies Nouvelles, Rond-point de l' échangeur de Solaize, BP 3, F-69360 Solaize (France); Mermet, Jean-Michel [Spectroscopy Forever, 01390 Tramoyes (France)

    2013-10-01

    The fundamentals, applications and latter developments of petroleum products analysis through inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS) are revisited in the present bibliographic survey. Sample preparation procedures for the direct analysis of fuels by using liquid sample introduction systems are critically reviewed and compared. The most employed methods are sample dilution, emulsion or micro-emulsion preparation and sample decomposition. The first one is the most widely employed due to its simplicity. Once the sample has been prepared, an organic matrix is usually present. The performance of the sample introduction system (i.e., nebulizer and spray chamber) depends strongly upon the nature and properties of the solution finally obtained. Many different devices have been assayed and the obtained results are shown. Additionally, samples can be introduced into the plasma by using an electrothermal vaporization (ETV) device or a laser ablation system (LA). The recent results published in the literature showing the feasibility, advantages and drawbacks of latter alternatives are also described. Therefore, the main goal of the review is the discussion of the different approaches developed for the analysis of crude oil and its derivates by inductively coupled plasma (ICP) techniques. - Highlights: • Analysis of petroleum products by inductively coupled plasma techniques is revisited. • Fundamental studies are included together with reports dealing with applications. • Conventional and non-conventional sample introduction methods are considered. • Sample preparation methods are critically compared and described.

  3. Jet quenching in heavy ion collisions at LHC

    CERN Document Server

    Lokhtin, Igor P

    2003-01-01

    We discuss the potential information about highly excited QCD-matter provided by medium-induced partonic energy loss, known as ``jet quenching''. In particular, with its large acceptance hadronic and electromagnetic calorimetry, the Compact Muon Solenoid detector at LHC collider is a promising device to study these effects. We present physics simulations of observables such as the jet distribution with impact parameter, the azimuthal anisotropy of jet quenching, and the effects of b-quark energy loss on the high-mass dimuon continuum and secondary charmonium production.

  4. A Dichotomy in Satellite Quenching Around L* Galaxies

    CERN Document Server

    Phillips, John I; Boylan-Kolchin, Michael; Bullock, James S; Cooper, Michael C; Tollerud, Erik J

    2013-01-01

    We examine the star formation properties of bright (~0.1 L*) satellites around isolated ~L* hosts in the local Universe using spectroscopically confirmed systems in the Sloan Digital Sky Survey DR7. Our selection method is carefully designed with the aid of N-body simulations to avoid groups and clusters. We find that satellites are significantly more likely to be quenched than a stellar mass-matched sample of isolated galaxies. Remarkably, this quenching occurs only for satellites of hosts that are themselves quenched: while star formation is unaffected in the satellites of star-forming hosts, satellites around quiescent hosts are more than twice as likely to be quenched than stellar-mass matched field samples. One implication of this is that whatever shuts down star formation in isolated, passive L* galaxies also plays at least an indirect role in quenching star formation in their bright satellites. The previously-reported tendency for "galactic conformity" in color/morphology may be a by-product of this ho...

  5. Hamiltonian truncation approach to quenches in the Ising field theory

    CERN Document Server

    Rakovszky, Tibor; Collura, Mario; Kormos, Márton; Takács, Gábor

    2016-01-01

    In contrast to lattice systems where powerful numerical techniques such as matrix product state based methods are available to study the non-equilibrium dynamics, the non-equilibrium behaviour of continuum systems is much harder to simulate. We demonstrate here that Hamiltonian truncation methods can be efficiently applied to this problem, by studying the quantum quench dynamics of the 1+1 dimensional Ising field theory using a truncated free fermionic space approach. After benchmarking the method with integrable quenches corresponding to changing the mass in a free Majorana fermion field theory, we study the effect of an integrability breaking perturbation by the longitudinal magnetic field. In both the ferromagnetic and paramagnetic phases of the model we find persistent oscillations with frequencies set by the low-lying particle excitations even for moderate size quenches. In the ferromagnetic phase these particles are the various non-perturbative confined bound states of the domain wall excitations, while...

  6. Quantum quench and scaling of entanglement entropy

    Science.gov (United States)

    Caputa, Paweł; Das, Sumit R.; Nozaki, Masahiro; Tomiya, Akio

    2017-09-01

    Global quantum quench with a finite quench rate which crosses critical points is known to lead to universal scaling of correlation functions as functions of the quench rate. In this work, we explore scaling properties of the entanglement entropy of a subsystem in a harmonic chain during a mass quench which asymptotes to finite constant values at early and late times and for which the dynamics is exactly solvable. When the initial state is the ground state, we find that for large enough subsystem sizes the entanglement entropy becomes independent of size. This is consistent with Kibble-Zurek scaling for slow quenches, and with recently discussed ;fast quench scaling; for quenches fast compared to physical scales, but slow compared to UV cutoff scales.

  7. Quenching star formation in cluster galaxies

    CERN Document Server

    Taranu, Dan S; Balogh, Michael L; Smith, Russell J; Power, Chris; Krane, Brad

    2012-01-01

    In order to understand the processes that quench star formation within rich clusters, we construct a library of subhalo orbits drawn from lambdaCDM cosmological N-body simulations of four rich clusters. The orbits are combined with models of star formation followed by quenching in the cluster environment to predict colours and spectroscopic line indices of satellite galaxies. Simple models with only halo mass-dependent quenching and without environmental (i.e. cluster-dependent) quenching fail to reproduce the observed cluster-centric colour and absorption linestrength gradients. Models in which star formation is instantly quenched at the virial radius also fail to match the observations. Better matches to the data are achieved by more complicated bulge-disc models in which the bulge stellar populations depend only on the galaxy subhalo mass while the disc quenching depends on the cluster environment. In the most successful models quenching begins at pericentre, operating on an exponential timescale of 2 -- 3...

  8. Syngas production by plasma treatments of alcohols, bio-oils and wood

    OpenAIRE

    Arabi, Khadija; Aubry, Olivier; Khacef, Ahmed; Cormier, Jean Marie

    2012-01-01

    International audience; Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. The Syngas produced from biomass can be used to power internal combustion engines, or, after purification, to supply fuel cells. The paper is summarizing results obtained through a non thermal arc plasma reactor at laboratory scale. A stationary discharge (I = 150mA) is used to perform physical diagnostic...

  9. Electromagnetic ion-cyclotron instability in a dusty plasma with product-bi-kappa distributions for the plasma particles

    Science.gov (United States)

    dos Santos, M. S.; Ziebell, L. F.; Gaelzer, R.

    2017-01-01

    We study the dispersion relation for parallel propagating ion-cyclotron (IC) waves in a dusty plasma, considering situations where the velocity dispersion along perpendicular direction is greater than along the parallel direction, and considering the use of product-bi-kappa (PBK) velocity distributions for the plasma particles. The results obtained by numerical solution of the dispersion relation, in a case with isotropic Maxwellian distributions for electrons and PBK distribution for ions, show the occurrence of the electromagnetic ion-cyclotron instability (EMIC), and show that the decrease in the kappa indexes of the PBK ion distribution leads to significant increase in the magnitude of the growth rates and in the range of wavenumber for which the instability occurs. On the other hand, for anisotropic Maxwellian distribution for ions and PBK distribution for electrons, the decrease of the kappa index in the PBK electron distribution contributes to reduce the growth rate of the EMIC instability, but the reduction effect is less pronounced than the increase obtained with ion PBK distribution with the same kappa index. The results obtained also show that, as a general rule, the presence of a dust population contributes to reduce the instability in magnitude of the growth rates and range, but that in the case of PBK ion distribution with small kappa indexes the instability may continue to occur for dust populations which would eliminate completely the instability in the case of bi-Maxwellian ion distributions. It has also been seen that the anisotropy due to the kappa indexes in the ion PBK distribution is not so efficient in producing the EMIC instability as the ratio of perpendicular and parallel ion temperatures, for equivalent value of the effective temperature.

  10. Perturbative versus non-perturbative aspects of jet quenching: in-medium breaking of color coherence

    CERN Document Server

    Beraudo, A

    2012-01-01

    The quenching of jets (and high-pT particle spectra) observed in heavy-ion collisions is interpreted as due to the energy lost by hard partons crossing the Quark Gluon Plasma. Here we review recent efforts to include in its modeling important qualitative features of QCD, like the correlations in multiple gluon emissions and the color-flow pattern in parton branchings. In particular, the modification of color connections among the partons of a shower developing in the presence of a medium is a generic occurrence accompanying parton energy-loss. We show how this effect can leave its fingerprints at the hadronization stage, leading by itself to a softening of hadron spectra and to an enhanced production of soft particles in jet-fragmentation.

  11. USE OF DIRECT QUENCHING AS AN ALTERNATIVE IN AUTOMOTIVE COMPONENTS MANUFACTURING

    Directory of Open Access Journals (Sweden)

    Hevlin Cristina de Almeida Costa

    2014-03-01

    Full Text Available This work has the aim to evaluate the replacement of quenching and hardening thermal treatment by direct quenching of forged safety washer component, to ensure and to maintain the mechanical properties of the products associated with competitive manufacturing costs. Supporting that, a statistical tool was used to delineate the processing routes, and forging tests were conducted at industrial scale. The effect of the different processing routes on the forged product was investigated through Finite Element Method and metallurgical analysis of the final product. The results showed the viability of the direct quenching with technical and economical advantages, once the control of the process parameters are guaranteed.

  12. Production of nitric oxide using a microwave plasma torch and its application to fungal cell differentiation

    Science.gov (United States)

    Na, Young Ho; Kumar, Naresh; Kang, Min-Ho; Cho, Guang Sup; Choi, Eun Ha; Park, Gyungsoon; Uhm, Han Sup

    2015-03-01

    The generation of nitric oxide by a microwave plasma torch is proposed for its application to cell differentiation. A microwave plasma torch was developed based on basic kinetic theory. The analytical theory indicates that nitric oxide density is nearly proportional to oxygen molecular density and that the high-temperature flame is an effective means of generating nitric oxide. Experimental data pertaining to nitric oxide production are presented in terms of the oxygen input in units of cubic centimeters per minute. The apparent length of the torch flame increases as the oxygen input increases. The various levels of nitric oxide are observed depending on the flow rate of nitrogen gas, the mole fraction of oxygen gas, and the microwave power. In order to evaluate the potential of nitric oxide as an activator of cell differentiation, we applied nitric oxide generated from the microwave plasma torch to a model microbial cell (Neurospora crassa: non-pathogenic fungus). Germination and hyphal differentiation of fungal cells were not dramatically changed but there was a significant increase in spore formation after treatment with nitric oxide. In addition, the expression level of a sporulation related gene acon-3 was significantly elevated after 24 h upon nitric oxide treatment. Increase in the level of nitric oxide, nitrite and nitrate in water after nitric oxide treatment seems to be responsible for activation of fungal sporulation. Our results suggest that nitric oxide generated by plasma can be used as a possible activator of cell differentiation and development.

  13. Syngas production by plasma treatments of alcohols, bio-oils and wood

    Science.gov (United States)

    Arabi, K.; Aubry, O.; Khacef, A.; Cormier, J.-M.

    2012-12-01

    Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. The Syngas produced from biomass can be used to power internal combustion engines, or, after purification, to supply fuel cells. The paper is summarizing results obtained through a non thermal arc plasma reactor at laboratory scale. A stationary discharge (I = 150mA) is used to perform physical diagnostics and also chemical analysis. The arc is formed between two electrodes made of graphite. We first present results on plasma-steam reforming of alcohols and bio-oils mixed in water. The outlet gas compositions are given from various alcohols and-bio-oils obtained at different experimental conditions. The second part of the paper is dedicated to a direct plasma treatment of wood (beech) at laboratory scale. One of the electrodes is surrounded by wood. The final part of the paper is a general discussion about efficiencies and comparisons of plasma treatments presented. The results obtained are discussed by considering the steam reforming reactions and the water gas shift reaction.

  14. Mass identification of the neutral products generated in the plasma treatment of polluted atmospheres

    Science.gov (United States)

    Seymour, David

    2013-09-01

    Plasmas produced using Dielectric Barrier Discharge (DBD) devices are very effective in the abatement of air pollution resulting from, for example, the emission of volatile organic compounds (VCOs) by a range of industrial and agricultural processes. The development and monitoring of effective DBD systems can be investigated by advanced mass spectrometric methods specifically configured for analysis at high and atmospheric pressures The present work involves the operation of a small DBD reactor which uses either a helium or nitrogen carrier gas to sustain the plasma to which may be added reactive gases, such as oxygen, as well as samples of pollutants such as chlorinated hydrocarbons, including trichloroethylene. The mass spectrometric analysis was performed using a specially configured system manufactured by Hiden Analytical Ltd. The DBD source may also be combined with a catalyst for plasma-enhanced catalysis. The neutral products of the reactions proceeding in the plasma at atmospheric pressure are sampled through the capillary sampling system which also reduces the pressure of the gas mixture delivered to the ionisation source of the quadrupole mass spectrometer. The ions produced are subsequently mass identified. We describe typical data and comment on the advantages of this technique.

  15. Jet quenching via jet collimation

    CERN Document Server

    Casalderrey-Solana, J; Wiedemann, U

    2011-01-01

    The strong modifications of dijet properties in heavy ion collisions measured by ATLAS and CMS provide important constraints on the dynamical mechanisms underlying jet quenching. In this work, we show that the transport of soft gluons away from the jet cone - jet collimation - can account for the observed dijet asymmetry with values of $\\hat{q}\\, L$ that lie in the expected order of magnitude. Further, we show that the energy loss attained through this mechanism results in a very mild distortion of the azimuthal angle dijet distribution.

  16. Jet Quenching via Jet Collimation

    CERN Document Server

    Casalderrey-Solana, Jorge; Wiedemann, Urs Achim

    2011-01-01

    The ATLAS Collaboration recently reported strong modifications of dijet properties in heavy ion collisions. In this work, we discuss to what extent these first data constrain already the microscopic mechanism underlying jet quenching. Simple kinematic arguments lead us to identify a frequency collimation mechanism via which the medium efficiently trims away the soft components of the jet parton shower. Through this mechanism, the observed dijet asymmetry can be accomodated with values of $\\hat{q}\\, L$ that lie in the expected order of magnitude.

  17. Cold atmospheric pressure plasma treatment of ready-to-eat meat: Inactivation of Listeria innocua and changes in product quality

    DEFF Research Database (Denmark)

    Röd, Sara Katrine; Hansen, Flemming; Leipold, Frank;

    Sliced ready-to-eat (RTE) meat products are susceptible to growth of the foodborne pathogenic bacterium, Listeria monocytogenes. Cold atmospheric pressure plasma (CAPP) may be applicable for surface decontamination in sealed bags thus avoiding recontamination. Plasmas (Fig. 1), created in neutral...

  18. Quenching Simulation of PM Coated Tools

    Institute of Scientific and Technical Information of China (English)

    AxelHoftert; WernerTheisen; ChristophBroeckmann

    2004-01-01

    HIP cladding is a powder metallurgical coating technique used in the production of wear parts and tools. In many cases the composite components consist of carbide-free hot-work steel as base material and wear resistant carbide-rich PM cold-work steel as coating material. To ensure operativeness a heat tleatment matched to the substrate and coating material is required. Dissimilar phase tlansformation behaviour and different thermal expansion coefficients of layer and substrate entail inner stresses affecting the tlansformation kinetics in tam. In order to get a deeper insight into these effects Finite Element simulation tools are used. On the one hand, the tlansient heat conduction problem of the quenching process has to be solved. Non-linear boundary conditions and phase transformation of both, substrate and layer are considered. On the other hand, the mechanical response is calculated. The overall aim of the investigation is an improvement of common heat treatment techniques used for HIP cladded wear parts.

  19. Quenching Simulation of PM Coated Tools

    Institute of Scientific and Technical Information of China (English)

    Axel H(o)fter; Werner Theisen; Christoph Broeckmann

    2004-01-01

    HIP cladding is a powder metallurgical coating technique used in the production of wear parts and tools. In many cases the composite components consist of carbide-free hot-work steel as base material and wear resistant carbide-rich PM cold-work steel as coating material. To ensure operativeness a heat treatment matched to the substrate and coating material is required. Dissimilar phase transformation behaviour and different thermal expansion coefficients of layer and substrate entail inner stresses affecting the transformation kinetics in turn. In order to get a deeper insight into these effects Finite Element simulation tools are used. On the one hand, the transient heat conduction problem of the quenching process has to be solved. Non-linear boundary conditions and phase transformation of both, substrate and layer are considered. On the other hand, the mechanical response is calculated. The overall aim of the investigation is an improvement of common heat treatment techniques used for HIP cladded wear parts.

  20. Products and mechanisms of the oxidation of organic compounds in atmospheric air plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Marotta, Ester; Schiorlin, Milko; Paradisi, Cristina [Department of Chemical Sciences, Universita di Padova, Via Marzolo 1, 35131 Padova (Italy); Rea, Massimo, E-mail: cristina.paradisi@unipd.i [Department of Electrical Engineering, Universita di Padova, 35131 Padova (Italy)

    2010-03-31

    Atmospheric plasma-based technologies are developing as a powerful means for air purification, specifically for the oxidation of organic pollutants. To achieve a better control on the emissions produced by such treatments mechanistic insight is needed in the complex reactions of volatile organic compounds (VOCs) within the plasma. An account is given here of our comparative studies of the behaviour of model VOCs in response to different corona regimes (+dc, -dc and +pulsed) implemented within the same flow reactor. Model VOCs considered include two alkanes (n-hexane and i-octane), one aromatic hydrocarbon (toluene) and two halogenated methanes, dibromomethane (CH{sub 2}Br{sub 2}) and dibromodifluoromethane (CF{sub 2}Br{sub 2}, halon 1202). Efficiency and product data are reported and discussed as well as various possible initiation reactions. A powerful diagnostic tool is ion analysis, performed by atmospheric pressure chemical ionization-mass spectrometry: it provides a map of major ions and ion-molecule reactions and a rationale for interpreting current/voltage characteristics of dc coronas. It is shown that, depending on the specific VOC and corona regime adopted, different initiation steps prevail in the VOC-oxidation process and that the presence of a VOC, albeit in small amounts (500 ppm), can greatly affect some important plasma properties (ion population, current/voltage profile, post-discharge products).

  1. Pyrolysis of Polyolefins Using Rotating Arc Plasma Technology for Production of Acetylene

    Directory of Open Access Journals (Sweden)

    Ming Zhang

    2017-04-01

    Full Text Available Polyolefin, as one of the most widely used macromolecule materials, has been one of the most serious threats to the environment. Current treatment methods of waste polyolefin including landfill, incineration, and thermal degradation have suffered from severe problems such as secondary pollution and the generation of other toxic substances. In this article, we report for the first time a high-efficiency method to produce high-value C2H2 from polyolefins using a rotating direct current arc plasma reactor, using polyethylene and polypropylene as feedstocks. The essence of this method is that a reductive atmosphere of pyrolysis enables a thermodynamic preference to C2H2 over other carbon-containing gas and the rotating direct current arc plasma reactor allows for a uniform distribution of high temperature to ensure high conversion of polymers. Thermodynamic simulation of product composition was performed, and the effect of plasma input power, polyolefin feed rate, and working gas flow rate on the pyrolysis results was experimentally investigated. It was found that, with proper parameter control, approximately complete conversion of carbon in polyolefin could be obtained, with a C2H2 selectivity higher than 80% and a C2H2 yield higher than 70%. These results not only create new opportunities for the reuse of polymer waste, but are also instructive for the green production of C2H2.

  2. Highly effective sorbents obtained by treating agrowaste products in cold plasma

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Sorbents are widely used in purification of various liquids and gases, offering a universal means for wastewater and air cleaning. The most promising sorbents are those obtained from agrowaste products such as rice or buckwheat husk. Processing of husk in cold plasma modifies the composition, structure and surface properties of the raw material and raises its porosity, thus substantially improving the sorption properties of the final product.Husk as a raw material for producing sorbents has the following advantageous properties: (1) appropriate chemical composition; (2) low cost; (3) high dispersity, due to which there is no need in any special treatment of the material prior to its exposing to plasma; (4) scaly structure and developed porous surface ensuring a high surface-to-volume ratio. The best properties are displayed by the sorbents obtained in cold plasma under reduced pressures of 53.2 Pa. The raw naterial traverses the region occupied by the plasma and, as it does so, it gets heated up to a temperature of 250 - 350 ℃. The whole process involves two stages: combustion of the raw material and modification of its properties under the action of the plasma. The combustion proceeds due to the oxygen contained in the starting material. During the combustion, the hydrogen contained in the starting material and some part of the carbon also burn out.The resultant scaly sorbent is accumulated in a cooler. The scales are black; they range in sizes from 1mm to 5 mm.The sorbents obtained are remarkable for their useful properties and outperform most of the traditional sorbents used in modern industry. The starting materials are inexpensive, and their resources are almost unlimited. The sorbents have rather a low production cost (1.8-2.5($)/kg). The sorbents can be used for cleaning hydrosphere from water pollutants on a large scale. The degree of cleaning water surface from oil products with sorbents was a subject of investigation. The highest degree of purification

  3. Uncertainty propagation in modeling of plasma-assisted hydrogen production from biogas

    Science.gov (United States)

    Zaherisarabi, Shadi; Venkattraman, Ayyaswamy

    2016-10-01

    With the growing concern of global warming and the resulting emphasis on decreasing greenhouse gas emissions, there is an ever-increasing need to utilize energy-production strategies that can decrease the burning of fossil fuels. In this context, hydrogen remains an attractive clean-energy fuel that can be oxidized to produce water as a by-product. In spite of being an abundant species, hydrogen is seldom found in a form that is directly usable for energy-production. While steam reforming of methane is one popular technique for hydrogen production, plasma-assisted conversion of biogas (carbon dioxide + methane) to hydrogen is an attractive alternative. Apart from producing hydrogen, the other advantage of using biogas as raw material is the fact that two potent greenhouse gases are consumed. In this regard, modeling is an important tool to understand and optimize plasma-assisted conversion of biogas. The primary goal of this work is to perform a comprehensive statistical study that quantifies the influence of uncertain rate constants thereby determining the key reaction pathways. A 0-D chemical kinetics solver in the OpenFOAM suite is used to perform a series of simulations to propagate the uncertainty in rate constants and the resulting mean and standard deviation of outcomes.

  4. Holographic quenches and anomalous transport

    Science.gov (United States)

    Ammon, Martin; Grieninger, Sebastian; Jimenez-Alba, Amadeo; Macedo, Rodrigo P.; Melgar, Luis

    2016-09-01

    We study the response of the chiral magnetic effect due to continuous quenches induced by time dependent electric fields within holography. Concretely, we consider a holographic model with dual chiral anomaly and compute the electric current parallel to a constant, homogeneous magnetic field and a time dependent electric field in the probe approximation. We explicitly solve the PDEs by means of pseudospectral methods in spatial and time directions and study the transition to an universal "fast" quench response. Moreover, we compute the amplitudes, i.e., residues of the quasi normal modes, by solving the (ODE) Laplace transformed equations. We investigate the possibility of considering the asymptotic growth rate of the amplitudes as a well defined notion of initial time scale for linearized systems. Finally, we highlight the existence of Landau level resonances in the electrical conductivity parallel to a magnetic field at finite frequency and show explicitly that these only appear in presence of the anomaly. We show that the existence of these resonances induces, among others, a long-lived AC electric current once the electric field is switched off.

  5. Plasma treatment of crane rails

    Directory of Open Access Journals (Sweden)

    Владислав Олександрович Мазур

    2016-07-01

    Full Text Available Crane operation results in wear and tear of rails and crane wheels. Renovation and efficiency of these details is therefore relevant. Modern technologies of wheels and rails restoration use surfacing or high-frequency currents treatment. Surface treatment with highly concentrated streams of energy- with a laser beam, plasma jet- is a promising direction.. It is proposed to increase the efficiency of crane rails by means of surface plasma treatment. The modes of treatment have been chosen.. Modelling of plasma jet thermal impact on a solid body of complex shape has been made. Plasma hardening regimes that meet the requirements of production have been defined. Structural transformation of the material in the crane rails on plasma treatment has been investigated. It has been concluded that for carbon and low alloy crane steels the plasma exposure zone is characterized by a high degree of hardened structure dispersion and higher hardness as compared to the hardness after high-frequency quenching. As this takes place phase transformations are both shift (in the upper zone of plasma influence and fluctuation (in the lower zone of the plasma. With high-speed plasma heating granular or lamellar pearlite mainly transforms into austenite. The level of service characteristics of hardened steel, which is achieved in this case is determined by the kinetics and completeness of pearlite → austenite transformation. For carbon and low alloy rail steels plasma hardening can replace bulk hardening, hardening by high-frequency currents, or surfacing. The modes for plasma treatment which make it possible to obtain a surface layer with a certain service characteristics have been defined

  6. Upgrade of the IGN-14 neutron generator for research on detection of fusion-plasma products

    Energy Technology Data Exchange (ETDEWEB)

    Igielski, Andrzej; Kurowski, Arkadiusz; Janik, Władysław; Gabańska, Barbara; Woźnicka, Urszula, E-mail: Urszula.Woznicka@ifj.edu.pl

    2015-10-11

    The fast neutron generator (IGN-14) at the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Kraków (Poland) is a laboratory multi-purpose experimental device. Neutrons are produced in a beam-target D–D or D–T reactions. A new vacuum chamber installed directly to the end of the ion guide of IGN-14 makes it possible to measure not only neutrons but also alpha particles in the presence of a mixed radiation field of other accompanying reaction products. The new experimental setup allows test detectors dedicated to spectrometric measurements of thermonuclear fusion reaction products. - Highlights: • Nuclear reactions at the target correspond to the fusion reaction in hot plasma. • Measuring vacuum chamber has been built and installed. • Spatial distribution of the particle mixed fields in chamber was calculated. • New experimental setup for tests of detectors dedicated to measure of fusion reaction products.

  7. Neural Variability Quenching Predicts Individual Perceptual Abilities.

    Science.gov (United States)

    Arazi, Ayelet; Censor, Nitzan; Dinstein, Ilan

    2017-01-04

    Neural activity during repeated presentations of a sensory stimulus exhibits considerable trial-by-trial variability. Previous studies have reported that trial-by-trial neural variability is reduced (quenched) by the presentation of a stimulus. However, the functional significance and behavioral relevance of variability quenching and the potential physiological mechanisms that may drive it have been studied only rarely. Here, we recorded neural activity with EEG as subjects performed a two-interval forced-choice contrast discrimination task. Trial-by-trial neural variability was quenched by ∼40% after the presentation of the stimulus relative to the variability apparent before stimulus presentation, yet there were large differences in the magnitude of variability quenching across subjects. Individual magnitudes of quenching predicted individual discrimination capabilities such that subjects who exhibited larger quenching had smaller contrast discrimination thresholds and steeper psychometric function slopes. Furthermore, the magnitude of variability quenching was strongly correlated with a reduction in broadband EEG power after stimulus presentation. Our results suggest that neural variability quenching is achieved by reducing the amplitude of broadband neural oscillations after sensory input, which yields relatively more reproducible cortical activity across trials and enables superior perceptual abilities in individuals who quench more.

  8. On the role of atomic metastability in the production of Balmer line radiation from ‘cold’ atomic hydrogen, deuterium and hydrogenic ion impurities in fusion edge plasmas

    Science.gov (United States)

    Hey, J. D.

    2012-03-01

    Published arguments, which assign an important role to atomic metastability in the production of ‘narrow’ Zeeman component radiation from the boundary region of fusion plasmas, are examined critically in relation to l-redistribution by proton and electron collisions, and mixing of unperturbed atomic states by the ion microfield and microfield gradient. It is concluded that these important processes indeed severely constrain the contribution from ‘metastable’ states to the generation of the hydrogen Balmer spectra, for electron concentrations above 1012 cm-3, as pointed out before by the present author (Hey et al 1999 J. Phys. B: At. Mol. Opt. Phys. 32 3555). The analysis of collision-induced l-redistribution represents an extension of that used previously (Hey et al 1996 Contrib. Plasma Phys. 36 583), applicable up to higher electron densities. For comparison purposes, we also consider the question of metastability of ionized helium in a low-temperature plasma, and that of some common hydrogenic impurities (C5+ and Ne9+) in a hydrogen (deuterium) fusion plasma. While for low nuclear charge Z the metastability of 2s1/2 levels is quenched by the plasma environment, it is much reduced in high-Z ions owing to the rapid increase with Z of the two-photon electric dipole (2E1) and magnetic dipole (M1) spontaneous transition rates to the ground state, whereas the role of the plasma in these cases is less important. The main new principle elaborated in this work is the sensitivity of atomic line strengths, and hence collision strengths, to perturbation by the plasma environment for transitions between fine-structure sublevels of the same principal quantum number. As the plasma microfield strength grows, ‘allowed’ transitions diminish in strength, while ‘forbidden’ transitions grow. However, owing to violation of the parity selection rule, there is an overall loss of collision strength available to transitions, resulting from the appearance of significant

  9. Cold atmospheric pressure plasma treatment of ready-to-eat meat: Inactivation of Listeria innocua and changes in product quality

    DEFF Research Database (Denmark)

    Rød, Sara Katrine; Hansen, Flemming; Leipold, Frank

    2012-01-01

    The application of cold atmospheric pressure plasma for decontamination of a sliced ready-to-eat (RTE) meat product (bresaola) inoculated with Listeria innocua was investigated. Inoculated samples were treated at 15.5, 31, and 62 W for 2–60 s inside sealed linear-low-density-polyethylene bags...... the sensory threshold level. Surface colour changes included loss of redness of ∼40% and 70% after 1 and 14 days of storage, respectively, regardless of plasma treatment. The results indicate that plasma may be applicable in surface decontamination of pre-packed RTE food products. However, oxidation may...

  10. a Thermohydraulic-Quenching Code for Superconducting Magnets in Network Circuits

    Science.gov (United States)

    Feng, Jun; Schultz, Joel; Minervini, Joe

    2010-04-01

    A thermohydraulic-quench code "Solxport3D-Quench" has been developed for a system of superconducting and normal solenoid magnets with supply network circuits. Each power supply network circuit consists of at least one superconducting magnet with parallel circuits including voltage sources, resistors or diodes. When used for analysis of a magnetic confinement fusion device, the plasma currents and passive structure eddy currents are also included in all scenarios. The simulation starts from superconducting stage for each magnet coil. The superconducting stage switches to quench stage if any one of the superconducting magnets quenches (i.e., exceeding the current sharing temperature.) It is followed by the dumping stage after a given quench detection time. The recovery of the superconducting stage is allowed at any time step before dumping. The currents of each magnetic coil are calculated by a time-difference method. The thermohydraulic parameters during superconducting and quench/dumping stage are obtained by a finite element method. The size and location of each finite element are dynamically defined at each time step during quench and dumping. Calibrations against test data are presented.

  11. Modifying the fatty acid profile of dairy products through feedlot technology lowers plasma cholesterol of humans consuming the products.

    Science.gov (United States)

    Noakes, M; Nestel, P J; Clifton, P M

    1996-01-01

    Intake of milk and butter has been clearly associated with higher coronary heart disease rates in different countries and this is likely to be mediated by the hypercholesterolemic effect of dairy fat. Fat-modified dairy products are an innovation involving a technology in which protected unsaturated lipids are fed to ruminants resulting in milk and tissue lipids with reduced saturated fatty acids. We examined the impact of these novel dairy fats on plasma lipids in a human dietary trial. Thirty-three men and women participated in an 8-wk randomized crossover trial comparing fat-modified with conventional dairy products. The trial consisted of a 2-wk low-fat baseline period followed by two 3-wk intervention phases. During the test periods, the fat-modified products resulted in a significant 0.28-mmol/L (4.3%) lowering of total cholesterol (P dairy products, if applied to populations typical of developed Western countries, represents a potential strategy to lower the risk of coronary heart disease without any appreciable change in customary eating patterns.

  12. Hydrogen and Carbon Black Production from the Degradation of Methane by Thermal Plasma

    Directory of Open Access Journals (Sweden)

    Leila Cottet

    2014-05-01

    Full Text Available Methane gas (CH4 is the main inducer of the so called greenhouse gases effect. Recent scientific research aims to minimize the accumulation of this gas in the atmosphere and to develop processes capable of producing stable materials with added value. Thermal plasma technology is a promising alternative to these applications, since it allows obtaining H2 and solid carbon from CH4, without the parallel formation of byproducts such as CO2 and NOx. In this work, CH4 was degraded by thermal plasma in order to produce hydrogen (H2 and carbon black. The degradation efficiency of CH4, selectivity for H2 production as well as the characterization of carbon black were studied. The best results were obtained in the CH4 flow rate of 5 L min-1 the degradation percentage and the selectivity for H2 production reached 98.8 % and 48.4 %, respectively. At flow rates of less than 5 L min-1 the selectivity for H2 production increases and reaches 91.9 %. The carbon black has obtained amorphous with hydrophobic characteristics and can be marketed to be used in composite material, and can also be activated chemically and/or physically and used as adsorbent material.

  13. Syngas production from tar reforming by microwave plasma jet at atmospheric pressure: power supplied influence

    Science.gov (United States)

    de Souza Medeiros, Henrique; Justiniano, Lucas S.; Gomes, Marcelo P.; Soares da Silva Sobrinho, Argemiro; Petraconi Filho, Gilberto

    2013-09-01

    Now a day, scientific community is searching for new fuels able to replace fossil fuels with economic and environment gains and biofuel play a relevant rule, mainly for the transport sector. A major process to obtaining such type of renewable resource is biomass gasification. This process has as product a gas mixture containing CO, CH4, and H2 which is named synthesis gas (syngas). However, an undesirable high molecular organic species denominated tar are also produced in this process which must be removed. In this work, results of syngas production via tar reforming in the atmospheric pressure microwave discharge having as parameter the power supply. Argon, (argon + ethanol), and (argon + tar solution) plasma jet were produced by different values of power supplied (from 0.5 KW to 1.5 KW). The plasma compounds were investigated by optical spectroscopy to each power and gas composition. The main species observed in the spectrum are Ar, CN, OII, OIV, OH, H2, H(beta), CO2, CO, and SIII. This last one came from tar. The best value of the power applied to syngas production from tar reforming was verified between 1.0 KW and 1.2 KW. We thank the following institutions for financial support: CNPq, CAPES, and FAPESP.

  14. Parameterization of x-ray production in laser-produced plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Peek, J.M.

    1980-10-01

    A simple and algebraically tractable model is developed for the efficiency of x-ray production in a certain spectral region by laser driven plasmas. The model is used as a interpolation/extrapolation device for experimental and theoretical results from three different target concepts. These tests indicate that it is of use in its intended capacity. Certain relationships between independent parameters and scaling laws also result from this construction. Most notable among these is the prediction that the efficiency for producing line radiation in a certain narrow energy range scales like the inverse square of this energy.

  15. Plasma assisted fuel reforming for on-board hydrogen rich gas production

    OpenAIRE

    Darmon, Adeline; Rollier, Jean-Damien; Duval, Emmanuelle; Gonzalez-Aguilar, Jose; Metkemeijer, Rudolf; Fulcheri, Laurent

    2006-01-01

    Texte disponible en suivant le lien ci-dessous : http://www.cder.dz/A2H2/Medias/Download/Proc%20PDF/PARALLEL%20SESSIONS/%5BS06%5D%20Production%20-%20Hydrocarbons/14-06-06/162.pdf; International audience; Plasma assisted fuel reforming technology appears particularly attractive for automotive applications, especially regarding compactness, response time and absence of catalyst element. In 2003, Renault and CEP have initiated a research programme on this subject. A test bench allowing reformer ...

  16. Chemical Equilibration and Dilepton Production of Quark-Gluon Plasma at RHIC Energies

    Institute of Scientific and Technical Information of China (English)

    龙家丽; 贺泽君; 马国亮; 马余刚; 刘波

    2004-01-01

    An evolution model of the chemically equilibrating quark-gluon plasma system has been established based on the Jiittner distribution function of partons. By studying the dilepton production of the system, we find that due to high initial temperature, large gluon density of the system as well as large gluon fusion gg → c(c-) cross section in the intermediate mass region, a dominant contribution to dileptons with intermediate masses is provided by quark-antiquark annihilation qq → l(l-) and, especially, thermal charmed quarks from the gluon fusion gg → c(c-) and quark-antiquark annihilation qq → c(c-).

  17. Influence of austenitizing temperature on apparent morphologies of as-quenched microstructures of steels

    Institute of Scientific and Technical Information of China (English)

    LIU Yue-jun; LI Yi-min; HUANG Bai-yun

    2006-01-01

    The effects of austenitizing temperature on the morphologies and substructures of as-quenched microstructure were investigated by using 13 medium and high carbon steels. The formation reasons of various morphologies of martensite quenched at different austenitizing temperatures were also studied. The results show that the packet martensite in medium and high carbon steels quenched at higher austenitizing temperature is entirely different from that in as-quenched low carbon steels, which is still plate martensite, and not lath martensite. All the change laws of as-quenched microstructures in medium and high carbon steels are identical with an increase in austenitizing temperature, and the austenitizing temperature can merely change the combined morphology of martensitic platelets,but cannot alter the type of product of martensitic transformation in commercial steels.

  18. On the O2(a1Δ) quenching by vibrationally excited ozone

    Science.gov (United States)

    Azyazov, V. N.; Mikheyev, P. A.; Heaven, M. C.

    2010-09-01

    The development of a discharge oxygen iodine laser (DOIL) requires efficient production of singlet delta oxygen (O2(a)) in electric discharge. It is important to understand the mechanisms by which O2(a) is quenched in these devices. To gain understanding of this mechanisms quenching of O2(a) in O(3P)/O2/O3/CO2/He/Ar mixtures has been investigated. Oxygen atoms and singlet oxygen molecules were produced by the 248 nm laser photolysis of ozone. The kinetics of O2(a) quenching were followed by observing the 1268 nm fluorescence of the O2 a --> X transition. Fast quenching of O2(a) in the presence of oxygen atoms and molecules was observed. The mechanism of the process has been examined using kinetic models, which indicate that quenching by vibrationally excited ozone is the dominant reaction.

  19. Nonthermal plasma reactors for the production of light hydrocarbon olefins from heavy oil

    Directory of Open Access Journals (Sweden)

    Prieto G.

    2003-01-01

    Full Text Available During the last decade, nonthermal plasma technology was applied in many different fields, focusing attention on the destruction of harmful compounds in the air. This paper deals with nonthermal plasma reactors for the conversion of heavy oil into light hydrocarbon olefins, to be employed as gasoline components or to be added in small amounts for the catalytic reduction of nitrogen oxide compounds in the treatment of exhaust gas at power plants. For the process, the plate-plate nonthermal plasma reactor driven by AC high voltage was selected. The reactor was modeled as a function of parameter characteristics, using the methodology provided by the statistical experimental design. The parameters studied were gap distance between electrodes, carrier gas flow and applied power. Results indicate that the reactions occurring in the process of heavy oil conversion have an important selective behavior. The products obtained were C1-C4 hydrocarbons with ethylene as the main compound. Operating the parameters of the reactor within the established operative window of the system and close to the optimum conditions, efficiencies as high as 70 (mul/joule were obtained. These values validate the process as an in-situ method to produce light olefins for the treatment of nitrogen oxides in the exhaust gas from diesel engines.

  20. Numerical Analysis of Microdischarge Oxygen Plasma and Prediction of Ozone Production Efficiency

    Science.gov (United States)

    Kawano, Satoyuki; Misaka, Takashi

    In this research, numerical simulation of oxygen plasma produced by dielectric barrier discharge (DBD) is made as a basic research for the application of bioprocesses such as sterilization. Numerical simulation is based on an appropriate modeling of microdischarges including 9 kinds of species and 54 chemical reactions. Behavior of the oxygen plasma is analyzed by finite difference method in two-dimensional computational region. The detailed characteristics of filamentous discharge formed between parallel dielectric surfaces which cover the electrodes are investigated. The qualitative tendency of the discharge formation process agrees with the previous experimental observation. Ozone production efficiency (OPE) is obtained and compared with experimental results. Dependency of reduced electric field E/n on OPE is investigated by comparing the numerical results with previous experimental results by other researcher, where E/n is the ratio of electric field EE to number density n of neutral molecule in the gas. It is confirmed that the present numerical simulation has practically enough accuracy for the evaluation of the OPE to optimize the oxygen plasma sterilization devices.

  1. Investigation of helium ion production in constricted direct current plasma ion source with layered-glows

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yuna [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Chung, Kyoung-Jae, E-mail: jkjlsh1@snu.ac.kr [Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Park, Yeong-Shin [Samsumg Electronics Co. Ltd., Gyeonggi 445-701 (Korea, Republic of); Hwang, Y. S. [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)

    2014-02-15

    Generation of helium ions is experimentally investigated with a constricted direct current (DC) plasma ion source operated at layered-glow mode, in which electrons could be accelerated through multiple potential structures so as to generate helium ions including He{sup 2+} by successive ionization collisions in front of an extraction aperture. The helium discharge is sustained with the formation of a couple of stable layers and the plasma ball with high density is created near the extraction aperture at the operational pressure down to 0.6 Torr with concave cathodes. The ion beam current extracted with an extraction voltage of 5 kV is observed to be proportional to the discharge current and inversely proportional to the operating pressure, showing high current density of 130 mA/cm{sup 2} and power density of 0.52 mA/cm{sup 2}/W. He{sup 2+} ions, which were predicted to be able to exist due to multiple-layer potential structure, are not observed. Simple calculation on production of He{sup 2+} ions inside the plasma ball reveals that reduced operating pressure and increased cathode area will help to generate He{sup 2+} ions with the layered-glow DC discharge.

  2. HARDENING-RELATED DEFORMATIONS OF GEAR WHEELS AFTER VACUUM CARBURISING AND QUENCHING IN GAS

    Directory of Open Access Journals (Sweden)

    Wojciech Stachurski

    2017-03-01

    Full Text Available The purpose of modern surface hardening technology is obtaining reproducible, precisely planned parameters of the carburized layer, minimizing the negative phenomena that result in dimensional changes after hardening and making it possible to determine the nature and magnitude of these changes. This concerns mainly the concept of single-piece flow in heat treatment applied for the purposes of mass production, employing a special autonomous 4D Quenching chamber for high pressure gas quenching (HPGQ. The main components of the 4D Quenching chamber include a system of cooling nozzles surrounding the processed item and providing a uniform inflow of cooling gas from all directions (3D and a table rotating together with the item processed, contributing to uniform cooling (4D. Within the framework of this paper there was studied the impact of gear wheel quenching in a 4D Quenching chamber using nitrogen at pressure of 6 and 10 bar on changes in geometry. Geometric measurements of facewidth of gear, hole diameter and outside diameter were performed before and after carburization and quenching. The results obtained allowed us to determine the impact of quenching pressure inside a 4D Quenching chamber on dimensional changes in gear wheels analyzed. The thermo-chemical treatment resulted in a decrease in outside diameters and hole diameters measured and an increase in facewidth of gears.

  3. Photolytic production of C/sup 2/H: collisional quenching of A tilde /sup 2/II. -->. X tilde /sup 2/Sigma/sup +/ infrared emission and the removal of excited C/sub 2/H

    Energy Technology Data Exchange (ETDEWEB)

    Shokoohi, F.; Watson, T.A.; Reisler, H.; Kong, F.; Renlund, A.M.; Wittig, C.

    1986-10-23

    The authors report the observation of time-resolved C/sub 2/H A tilde /sup 2/II ..-->.. X tilde /sup 2/Sigma/sup +/ infrared emission (1-5 ..mu..m) following the 193-nm photolyses of C/sub 2/H/sub 2/ and C/sub 2/HBr. Quenching of this emission by numerous collision partners (M) under pseudo-first-order conditions leads to large bimolecular rate coefficients (e.g. > 10/sup -11/ cm/sup 3/ molecule/sup -1/ s/sup -1/, except when M is a rare gas or N/sub 2/). Although such rate coefficients can be assigned to the quenching of fluorescence, they do not represent state-to-state processes, since quenching is due to an intricate combination of reactive, radiative, and energy-transfer processes. In separate experiments, rate coefficients are determined by monitoring the time-resolved CH A/sup 2/..delta.. ..-->.. X/sup 2/II chemiluminescence which is produced directly by the reaction of C/sub 2/H with O/sub 2/, and the C/sub 2/H species responsible for the CH emissions is identified as electronically and/or vibrationally excited C/sub 2/H. The above results are in agreement with recent molecular beam experiments that show that nascent C/sub 2/H contains considerably internal energy following the 193-nm photolysis of C/sub 2/H/sub 2/.

  4. Boiling and quenching heat transfer advancement by nanoscale surface modification.

    Science.gov (United States)

    Hu, Hong; Xu, Cheng; Zhao, Yang; Ziegler, Kirk J; Chung, J N

    2017-07-21

    All power production, refrigeration, and advanced electronic systems depend on efficient heat transfer mechanisms for achieving high power density and best system efficiency. Breakthrough advancement in boiling and quenching phase-change heat transfer processes by nanoscale surface texturing can lead to higher energy transfer efficiencies, substantial energy savings, and global reduction in greenhouse gas emissions. This paper reports breakthrough advancements on both fronts of boiling and quenching. The critical heat flux (CHF) in boiling and the Leidenfrost point temperature (LPT) in quenching are the bottlenecks to the heat transfer advancements. As compared to a conventional aluminum surface, the current research reports a substantial enhancement of the CHF by 112% and an increase of the LPT by 40 K using an aluminum surface with anodized aluminum oxide (AAO) nanoporous texture finish. These heat transfer enhancements imply that the power density would increase by more than 100% and the quenching efficiency would be raised by 33%. A theory that links the nucleation potential of the surface to heat transfer rates has been developed and it successfully explains the current finding by revealing that the heat transfer modification and enhancement are mainly attributed to the superhydrophilic surface property and excessive nanoscale nucleation sites created by the nanoporous surface.

  5. Hamiltonian truncation approach to quenches in the Ising field theory

    Directory of Open Access Journals (Sweden)

    T. Rakovszky

    2016-10-01

    Full Text Available In contrast to lattice systems where powerful numerical techniques such as matrix product state based methods are available to study the non-equilibrium dynamics, the non-equilibrium behaviour of continuum systems is much harder to simulate. We demonstrate here that Hamiltonian truncation methods can be efficiently applied to this problem, by studying the quantum quench dynamics of the 1+1 dimensional Ising field theory using a truncated free fermionic space approach. After benchmarking the method with integrable quenches corresponding to changing the mass in a free Majorana fermion field theory, we study the effect of an integrability breaking perturbation by the longitudinal magnetic field. In both the ferromagnetic and paramagnetic phases of the model we find persistent oscillations with frequencies set by the low-lying particle excitations not only for small, but even for moderate size quenches. In the ferromagnetic phase these particles are the various non-perturbative confined bound states of the domain wall excitations, while in the paramagnetic phase the single magnon excitation governs the dynamics, allowing us to capture the time evolution of the magnetisation using a combination of known results from perturbation theory and form factor based methods. We point out that the dominance of low lying excitations allows for the numerical or experimental determination of the mass spectra through the study of the quench dynamics.

  6. Hamiltonian truncation approach to quenches in the Ising field theory

    Science.gov (United States)

    Rakovszky, T.; Mestyán, M.; Collura, M.; Kormos, M.; Takács, G.

    2016-10-01

    In contrast to lattice systems where powerful numerical techniques such as matrix product state based methods are available to study the non-equilibrium dynamics, the non-equilibrium behaviour of continuum systems is much harder to simulate. We demonstrate here that Hamiltonian truncation methods can be efficiently applied to this problem, by studying the quantum quench dynamics of the 1 + 1 dimensional Ising field theory using a truncated free fermionic space approach. After benchmarking the method with integrable quenches corresponding to changing the mass in a free Majorana fermion field theory, we study the effect of an integrability breaking perturbation by the longitudinal magnetic field. In both the ferromagnetic and paramagnetic phases of the model we find persistent oscillations with frequencies set by the low-lying particle excitations not only for small, but even for moderate size quenches. In the ferromagnetic phase these particles are the various non-perturbative confined bound states of the domain wall excitations, while in the paramagnetic phase the single magnon excitation governs the dynamics, allowing us to capture the time evolution of the magnetisation using a combination of known results from perturbation theory and form factor based methods. We point out that the dominance of low lying excitations allows for the numerical or experimental determination of the mass spectra through the study of the quench dynamics.

  7. Quenched QCD near the chiral limit

    CERN Document Server

    Göckeler, M; Petters, D; Pleiter, D; Rakow, P E L; Schierholz, G

    2000-01-01

    A numerical study of quenched QCD for light quarks is presented using O(a)improved fermions. Particular attention is paid to the possible existence anddetermination of quenched chiral logarithms. A `safe' region to use for chiralextrapolations appears to be at and above the strange quark mass.

  8. Monte Carlo Tools for Jet Quenching

    OpenAIRE

    Zapp, Korinna

    2011-01-01

    A thorough understanding of jet quenching on the basis of multi-particle final states and jet observables requires new theoretical tools. This talk summarises the status and propects of the theoretical description of jet quenching in terms of Monte Carlo generators.

  9. Quenched chiral perturbation theory to one loop

    NARCIS (Netherlands)

    Colangelo, Gilberto; Pallante, Elisabetta

    1998-01-01

    We calculate the divergences of the generating functional of quenched chiral perturbation theory at one loop, and renormalize the theory by an appropriate definition of the counterterms. We show that the quenched chiral logarithms can be accounted for by defining a renormalized B0 parameter which, a

  10. Quenched Chiral Perturbation Theory to one loop

    NARCIS (Netherlands)

    Colangelo, G.; Pallante, E.

    1998-01-01

    The divergences of the generating functional of quenched Chiral Perturbation theory (qCHPT) to one loop are computed in closed form. We show how the quenched chiral logarithms can be reabsorbed in the renormalization of the B0 parameter of the leading order Lagrangian. Finally, we do the chiral powe

  11. Thermal quenching and electron traps in LSO

    Energy Technology Data Exchange (ETDEWEB)

    Kappers, L.A. E-mail: kappers@uconnvm.uconn.edu; Bartram, R.H.; Hamilton, D.S.; Lempicki, A.; Glodo, J

    2003-05-01

    It is demonstrated by comparison of thermoluminescence and scintillation light outputs of LSO as functions of radiation time that a previously suggested thermal quenching correction is inappropriate. Approximate solutions of rate equations are employed to infer absolute trap concentrations and to explore the effects of thermal quenching on the shapes of thermoluminescence glow curves.

  12. MSFC Electrostatic Levitator (ESL) Rapid Quench System

    Science.gov (United States)

    SanSoucie, Michael P.; Craven, Paul D.; Rogers, Jan R.

    2014-01-01

    The NASA Marshall Space Flight Center (MSFC) Electrostatic Levitator (ESL) Laboratory is a unique facility for investigators studying high-temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified, all without the interference of a container or data-gathering instrument. The ESL main chamber has been upgraded with the addition of a rapid quench system. This system allows samples to be dropped into a quench vessel that can be filled with a low melting point material, such as a gallium or indium alloy. Thereby allowing rapid quenching of undercooled liquid metals. Up to 8 quench vessels can be loaded into the quench wheel, which is indexed with LabVIEW control software. This allows up to 8 samples to be rapidly quenched before having to open the chamber. The system has been tested successfully on several zirconium samples. Future work will be done with other materials using different quench mediums. Microstructural analysis will also be done on successfully quench samples.

  13. Excitation mechanism and thermal emission quenching of Tb ions in silicon rich silicon oxide thin films grown by plasma-enhanced chemical vapour deposition—Do we need silicon nanoclusters?

    Energy Technology Data Exchange (ETDEWEB)

    Podhorodecki, A., E-mail: artur.p.podhorodecki@pwr.wroc.pl; Golacki, L. W.; Zatryb, G.; Misiewicz, J. [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Wang, J.; Jadwisienczak, W. [School of EECS, Ohio University, Stocker Center 363, Athens, Ohio 45701 (United States); Fedus, K. [Institute of Physics, Nicholas Copernicus University, Grudziadzka 5/7, 87-100 Torun (Poland); Wojcik, J.; Wilson, P. R. J.; Mascher, P. [Department of Engineering Physics and Centre for Emerging Device Technologies, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S4L7 (Canada)

    2014-04-14

    In this work, we will discuss the excitation and emission properties of Tb ions in a Silicon Rich Silicon Oxide (SRSO) matrix obtained at different technological conditions. By means of electron cyclotron resonance plasma-enhanced chemical vapour deposition, undoped and doped SRSO films have been obtained with different Si content (33, 35, 39, 50 at. %) and were annealed at different temperatures (600, 900, 1100 °C). The samples were characterized optically and structurally using photoluminescence (PL), PL excitation, time resolved PL, absorption, cathodoluminescence, temperature dependent PL, Rutherford backscattering spectrometry, Fourier transform infrared spectroscopy and positron annihilation lifetime spectroscopy. Based on the obtained results, we discuss how the matrix modifications influence excitation and emission properties of Tb ions.

  14. Nano-Disperse Borides and Carbides: Plasma Technology Production, Specific Properties, Economic Evaluation

    Science.gov (United States)

    Galevskii, G. V.; Rudneva, V. V.; Galevskii, S. G.; Tomas, K. I.; Zubkov, M. S.

    2016-04-01

    The experience of production and study on properties of nano-disperse chromium and titanium borides and carbides, and silicon carbide has been generalized. The structure and special service aspects of utilized plasma-metallurgical complex equipped with a three-jet direct-flow reactor with a capacity of 150 kW have been outlined. Processing, heat engineering and service life characteristics of the reactor are specified. The synthesis parameters of borides and carbides, as well as their basic characteristics in nano-disperse condition and their production flow diagram are outlined. Engineering and economic performance of synthesizing borides in laboratory and industrial conditions is assessed, and the respective segment of the international market as well. The work is performed at State Siberian Industrial University as a project part of the State Order of Ministry of Science and Education of the Russian Federation No. 11.1531/2014/K.

  15. Is there jet quenching in pPb?

    Energy Technology Data Exchange (ETDEWEB)

    Tywoniuk, Konrad, E-mail: konrad@ecm.ub.edu

    2014-06-15

    Many features of pPb collisions at the LHC resemble those of full-fledged PbPb collisions. This is suggestive of the formation of a similar deconfined quark–gluon plasma, though on a relatively smaller scale. We show that the resulting characteristic scales relevant for the quenching of high-p{sub ⊥} probes, and jets in particular, are nevertheless small for the relevant p{sub ⊥} range. This establishes these probes as clean observables of modifications on nuclear PDF's.

  16. Bioenergy and products from thermal pyrolysis of rice straw using plasma torch.

    Science.gov (United States)

    Shie, Je-Lueng; Tsou, Feng-Ju; Lin, Kae-Long; Chang, Ching-Yuan

    2010-01-01

    The aim of this work was to study the feasibility and operation performance of plasma torch pyrolysis of biomass wastes, taking rice straw as the target material. This novel method has several advantages including high heating rate, short heating time, no viscous tar and low residual char (7.45-13.78 wt.%) or lava. The productions of CO and H(2) are the major components (91.85-94.14 vol.%) in the gas products with relatively high reaction rates. The maximum concentrations of gaseous products occurring times are all below 1 min. Almost 90% of gaseous products were appeared in 4 min reaction time. The yield of H(2) increases with the increase of input power or temperature. With the increase of moisture (5-55 wt.%), the mass yields of H(2) and CO(2) also increase from the H(2)O decomposition. However, due to the CO(2) production, the accumulated volume fraction of syngas decreases with the increase of moisture.

  17. Production of hydroxyapatite layers on the plasma electrolytically oxidized surface of titanium alloys.

    Science.gov (United States)

    Lugovskoy, Alex; Lugovskoy, Svetlana

    2014-10-01

    Hydroxyapatite (HA) is a bioactive material that is widely used for improving the osseointegration of titanium dental implants. Titanium can be coated with HA by various methods, such as chemical vapor deposition (CVD), thermal spray, or plasma spray. HA coatings can also be grown on titanium surfaces by hydrothermal, chemical, and electrochemical methods. Plasma electrolytic oxidation (PEO), or microarc oxidation (MAO), is an electrochemical method that enables the production of a thick porous oxide layer on the surface of a titanium implant. If the electrolyte in which PEO is performed contains calcium and phosphate ions, the oxide layer produced may contain hydroxyapatite. The HA content can then be increased by subsequent hydrothermal treatment. The HA thus produced on titanium surfaces has attractive properties, such as a high porosity, a controllable thickness, and a considerable density, which favor its use in dental and bone surgery. This review summarizes the state of the art and possible further development of PEO for the production of HA on Ti implants.

  18. Non-equilibrium quantum plasmas in scalar QED photon production, magnetic and Debye masses and conductivity

    CERN Document Server

    Boyanovsky, D; Simionato, M

    2000-01-01

    We study the generation of a non-equilibrium plasma in scalar QED with N charged scalar fields through spinodal instabilities in the case of a super cooled second order phase transition and parametric amplification when the order parameter oscillates with large amplitude around the minimum of the potential.The focus is to study the non-equilibrium electromagnetic properties of the plasma, such as photon production, electric and magnetic screening and conductivity. A novel kinetic equation is introduced to compute photon production far away from equilibrium in the large N limit and lowest order in the electromagnetic coupling.During the early stages of the dynamics the photon density grows exponentially and asymptotically the amplitude and frequency distribution becomes \\sim alpha m^2/[lambda^2 ømega^3] with lambda the scalar self-coupling and m the scalar mass.In the case of a phase transition,electric and magnetic fields are correlated on distances xi(t) \\sim sqrt{t} during the early stages and the power sp...

  19. Transient Loschmidt echo in quenched Ising chains

    Science.gov (United States)

    Lupo, Carla; Schiró, Marco

    2016-07-01

    We study the response to sudden local perturbations of highly excited quantum Ising spin chains. The key quantity encoding this response is the overlap between time-dependent wave functions, which we write as a transient Loschmidt Echo. Its asymptotics at long time differences contain crucial information about the structure of the highly excited nonequilibrium environment induced by the quench. We compute the echo perturbatively for a weak local quench but for arbitrarily large global quench, using a cumulant expansion. Our perturbative results suggest that the echo decays exponentially, rather than power law as in the low-energy orthogonality catastrophe, a further example of quench-induced decoherence already found in the case of quenched Luttinger liquids. The emerging decoherence scale is set by the strength of the local potential and the bulk excitation energy.

  20. Quench Heater Studies for the LHC Magnets

    CERN Document Server

    Rodríguez-Mateos, F

    2001-01-01

    About 2000 LHC (CERN's Large Hadron Collider) superconducting magnets will be protected with quench heaters against development of excessive voltage and overheating after a resistive transition. The quench heater strips are powered by capacitor bank discharge power supplies. The strips are made of stainless steel partially plated with copper to reduce their resistance and to allow for the connection of quench heaters in series. The strips are embedded in between two polyimide foils. The initial power density and the current decay time determine the quench heater effectiveness. Since only one type of heater power supply will be available, the copper plating cycle is adapted for the various magnet types to keep the resistance of the heater circuit constant. Different quench heater designs have been tested on various prototype magnets to optimise the copper-plating cycle and the electric insulation of the heater strip. This paper summarises the experimental results and computations that allowed to finalise the h...

  1. QUENCH STUDIES AND PREHEATING ANALYSIS OF SEAMLESS

    Energy Technology Data Exchange (ETDEWEB)

    Palczewski, Ari [JLAB; Geng, Rongli [JLAB; Eremeev, Grigory [JLAB

    2013-09-01

    One of the alternative manufacturing technologies for SRF cavities is hydroforming from seamless tubes. Although this technology has produced cavities with gradient and Q-values comparable to standard EBW/EP cavities, a few questions remain. One of these questions is whether the quench mechanism in hydroformed cavities is the same as in standard electron beam welded cavities. Towards this effort Jefferson Lab performed quench studies on 2 9 cell seamless hydroformed cavities. These cavities include DESY's - Z163 and Z164 nine-cell cavities hydroformed at DESY. Initial Rf test results Z163 were published in SRF2011. In this report we will present post JLAB surface re-treatment quench studies for each cavity. The data will include OST and T-mapping quench localization as well as quench location preheating analysis comparing them to the observations in standard electron beam welded cavities.

  2. Products and bioenergy from the pyrolysis of rice straw via radio frequency plasma and its kinetics.

    Science.gov (United States)

    Tu, Wen-Kai; Shie, Je-Lung; Chang, Ching-Yuan; Chang, Chiung-Fen; Lin, Cheng-Fang; Yang, Sen-Yeu; Kuo, Jing T; Shaw, Dai-Gee; You, Yii-Der; Lee, Duu-Jong

    2009-03-01

    The radio frequency plasma pyrolysis technology, which can overcome the disadvantages of common pyrolysis methods such as less gas products while significant tar formation, was used for pyrolyzing the biomass waste of rice straw. The experiments were performed at various plateau temperatures of 740, 813, 843 and 880K with corresponding loading powers of 357, 482, 574 and 664W, respectively. The corresponding yields of gas products (excluding nitrogen) from rice straw are 30.7, 56.6, 62.5 and 66.5wt.% with respect to the original dried sample and the corresponding specific heating values gained from gas products are about 4548, 4284, 4469 and 4438kcalkg(-1), respectively, for the said cases. The corresponding combustible portions remained in the solid residues are about 64.7, 35, 28.2 and 23.5wt.% with specific heating values of 4106, 4438, 4328 and 4251kcalkg(-1) with respective to solid residues, while that in the original dried sample is 87.2wt.% with specific heating value of 4042kcalkg(-1). The results indicated that the amount of combustibles converted into gas products increases with increasing plateau temperature. The kinetic model employed to describe the pyrolytic conversion of rice straw at constant temperatures agrees well with the experimental data. The best curve fittings render the frequency factor of 5759.5s(-1), activation energy of 74.29kJ mol(-1) and reaction order of 0.5. Data and information obtained are useful for the future design and operation of pyrolysis of rice straw via radio frequency plasma.

  3. Gaseous hydrocarbon production by the reaction of coal char with hydrogen plasma at relatively lower microwave power

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, S.; Nishikubo, K.; Imamura, T. [Kyushu National Industrial Research Institute, Tosu (Japan)

    1998-07-01

    Experimental conditions such as reaction temperature, microwave power and reaction pressure were changed in the reaction of carbon with hydrogen plasma. Methane was major product and other hydrocarbons such as acetylene and C2-C4 hydrocarbons were also produced. Methane production shows its maximum at 700-900 K and at 30W of microwave power. 2 figs.

  4. Optimization of hydrogen production by Halobacterium salinarium coupled with E coli using milk plasma as fermentative substrate

    Directory of Open Access Journals (Sweden)

    Brijesh Prasad

    2011-08-01

    Full Text Available Batch experiments were conducted to investigate the fermentative hydrogen production by coupled system of Halobacterium salinarium and E. coli. Increase in the light intensity from 6000 lux to 12000 lux and changing the inoculums level of E coli resulted in 10 fold increase in the rate of hydrogen production using the coupled system. Statistical based design of experiments was applied to optimize the rate of hydrogen production using milk plasma,popularly known as cheese whey, a dairy industry byproduct. An optimal rate of hydrogen production of 56.7 ml/l h was achieved with 14.42 % (by volume of milk plasma and an initial pH of 6.6. The investigations provided information on achieving higher yields with milk plasma as substrate, its optimal concentration, and importance of media pH for producing higher rate of hydrogen.

  5. The association of plasma fluorescent oxidation products and chronic kidney disease: a case-control study.

    Science.gov (United States)

    Rebholz, Casey M; Wu, Tianying; Hamm, L Lee; Arora, Robin; Khan, Islam E; Liu, Yanxi; Chen, Chung-Shiuan; Mills, Katherine T; Rogers, Stephanie; Kleinpeter, Myra A; Simon, Eric E; Chen, Jing

    2012-01-01

    Plasma fluorescent oxidation products (FLOP) constitute a stable and easily measured biomarker of cumulative oxidative stress. However, their association with chronic kidney disease (CKD) has not been studied. We examined the association of FLOP and CKD in 201 CKD patients and 201 controls without CKD from the community. CKD was defined as an estimated glomerular filtration rate (eGFR) products): 215.2 (181.3-268.7) vs. 156.6 (139.6-177.3) fluorescent intensity units/ml, p products): 534.8 (379.3-842.4) vs. 269.9 (232.4-410.5) fluorescent intensity units/ml, p products): 51.4 (44.4-66.0) vs. 45.2 (38.3-51.7) fluorescent intensity units/ml, p = 0.002]. Compared with those with a FLOP level below the 75th percentile, participants with a FLOP level above the 75th percentile had increased odds of CKD after adjustment for covariables (FLOP1: odds ratio 13.1, 95% confidence interval 6.2-27.6; FLOP2: odds ratio 5.7, 95% confidence interval 2.9-11.1; FLOP3: odds ratio 2.4, 95% confidence interval 1.2-4.7). Levels of FLOP1, FLOP2 and FLOP3 were related to eGFR (p studies are warranted to elucidate its role in the development and progression of CKD. Copyright © 2012 S. Karger AG, Basel.

  6. The discharge mode transition and O(5p1) production mechanism of pulsed radio frequency capacitively coupled plasma

    Science.gov (United States)

    Liu, X. Y.; Hu, J. T.; Liu, J. H.; Xiong, Z. L.; Liu, D. W.; Lu, X. P.; Shi, J. J.

    2012-07-01

    The discharge mode transition from uniform plasma across the gas gap to the α mode happens at the rising phase of the pulsed radio frequency capacitively coupled plasma (PRF CCP). This transition is attributed to the fast increasing stochastic heating at the edge of sheath. In the second stage with the stable current and voltage amplitude, the consistency between experimental and numerical spatial-temporal 777 nm emission profile suggests that He* and He2* dominate the production of O(5p1) through dissociation and excitation of O2. Finally, the sterilization efficiency of PRF CCP is found to be higher than that of plasma jet.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-09-15

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

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

    Science.gov (United States)

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

    2006-09-01

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

  9. Production of stable, non-thermal atmospheric pressure rf capacitive plasmas using gases other than helium or neon

    Science.gov (United States)

    Park, Jaeyoung; Henins, Ivars

    2005-06-21

    The present invention enables the production of stable, steady state, non-thermal atmospheric pressure rf capacitive .alpha.-mode plasmas using gases other than helium and neon. In particular, the current invention generates and maintains stable, steady-state, non-thermal atmospheric pressure rf .alpha.-mode plasmas using pure argon or argon with reactive gas mixtures, pure oxygen or air. By replacing rare and expensive helium with more readily available gases, this invention makes it more economical to use atmospheric pressure rf .alpha.-mode plasmas for various materials processing applications.

  10. Quench-induced trapping of magnetic flux in annular Josephson junctions

    DEFF Research Database (Denmark)

    Aarøe, Morten; Monaco, R.; Rivers, R.;

    2008-01-01

    over 4 orders of magnitude. After the quench the result of the spontaneous production of topological defects, trapped fluxons, is unambiguously observed as zero-field steps in the DC I-V characteristic of the junction. A power-law scaling behavior of trapping probability versus quench rate is found...... with a critical exponent of 0.5 (within experimental error). The main experimental challenges are to generate many identical quenches with accurate cooling rate, to automate data analysis and acquisition, and to suppress external magnetic fields and noise by passive magnetic shielding and compensation....

  11. Quenching behaviour of quadrupole model magnets for the LHC inner triplets at Fermilab

    CERN Document Server

    Andreev, N; Bauer, P; Bossert, R; Brandt, J; Chichili, D R; Carson, J; Di Marco, J; Fehér, S; Glass, H; Kerby, J S; Lamm, M J; Makarov, A A; Nobrega, A; Novitski, I; Ogitsu, T; Orris, D; Ozelis, J P; Rabehl, Roger Jon; Robotham, W; Sabbi, G L; Schlabach, P; Sylvester, C D; Strait, J B; Tartaglia, M; Tompkins, J C; Yadav, S; Zlobin, A V; Caspi, S; McInturff, A D; Scanlan, R M; Ghosh, A

    2000-01-01

    The US-LHC Accelerator Project is responsible for the design and production of inner triplet high gradient quadrupoles for installation in the LHC Interaction Region. The quadrupoles are required to deliver a nominal field gradient of 215 T/m in a 70 mm bore, and operate in superfluid helium. As part of the magnet development program, a series of 2 m model magnets have been built and tested at Fermilab, with each magnet being tested over several thermal cycles. This paper summarizes the quench performance and analysis of the model magnets tested, including quench training, and the ramp rate and temperature of the magnet quench current. (7 refs).

  12. Assessment Of Surface-Catalyzed Reaction Products From High Temperature Materials In Plasmas

    Science.gov (United States)

    Allen, Luke Daniel

    Current simulations of atmospheric entry into both Mars and Earth atmospheres for the design of thermal protections systems (TPS) typically invoke conservative assumptions regarding surface-catalyzed recombination and the amount of energy deposited on the surface. The need to invoke such assumptions derives in part from lack of adequate experimental data on gas-surface interactions at trajectory relevant conditions. Addressing this issue, the University of Vermont's Plasma Test and Diagnostics Laboratory has done extensive work to measure atomic specie consumption by measuring the concentration gradient over various material surfaces. This thesis extends this work by attempting to directly diagnose molecular species production in air plasmas. A series of spectral models for the A-X and B-X systems of nitric oxide (NO), and the B-X system of boron monoxide (BO) have been developed. These models aim to predict line positions and strengths for the respective molecules in a way that is best suited for the diagnostic needs of the UVM facility. From the NO models, laser induced fluorescence strategies have been adapted with the intent of characterizing the relative quantity and thermodynamic state of NO produced bysurface-catalyzed recombination, while the BO model adds a diagnostic tool for the testing of diboride-based TPS materials. Boundary layer surveys of atomic nitrogen and NO have been carried out over water-cooled copper and nickel surfaces in air/argon plasmas. Translation temperatures and relative number densities throughout the boundary layer are reported. Additional tests were also conducted over a water-cooled copper surface to detect evidence of highly non-equilibrium effects in the form of excess population in elevated vibrational levels of the A-X system of NO. The tests showed that near the sample surface there is a much greater population in the upsilon'' = 1ground state than is predicted by a Boltzmann distribution.

  13. Design of continuous walking beam furnaces for quench and tempering of oil country tubulars

    Energy Technology Data Exchange (ETDEWEB)

    Casana, A.; Stabile, V.

    1982-09-01

    Explains how, because users of oil pipes demand higher steel qualities, with pipe uniformly treated inside and out, heat treatment plants have undergone a steady technological improvement. The trend of increased product quality has led to a tendency to interrelate the product both with the process and the production facility. The furnaces and quench and tempering processes are of particular importance in the overall production cycle for tube. Describes and illustrates some technical solutions realized in quenching and tempering walking beam furnaces. Furnace dimensions depend on the total heating and soaking time for the products. Presents diagram depicting refractory materials used for lining the walls and hearth of the walking beam furnaces.

  14. Quenching phenomena in natural circulation loop

    Energy Technology Data Exchange (ETDEWEB)

    Umekawa, Hisashi; Ozawa, Mamoru [Kansai Univ., Osaka (Japan); Ishida, Naoki [Daihatsu Motor Company, Osaka (Japan)

    1995-09-01

    Quenching phenomena has been investigated experimentally using circulation loop of liquid nitrogen. During the quenching under natural circulation, the heat transfer mode changes from film boiling to nucleate boiling, and at the same time flux changes with time depending on the vapor generation rate and related two-phase flow characteristics. Moreover, density wave oscillations occur under a certain operating condition, which is closely related to the dynamic behavior of the cooling curve. The experimental results indicates that the occurrence of the density wave oscillation induces the deterioration of effective cooling of the heat surface in the film and the transition boiling regions, which results in the decrease in the quenching velocity.

  15. Production, fate and pathogenicity of plasma microparticles in murine cerebral malaria.

    Directory of Open Access Journals (Sweden)

    Fatima El-Assaad

    2014-03-01

    Full Text Available In patients with cerebral malaria (CM, higher levels of cell-specific microparticles (MP correlate with the presence of neurological symptoms. MP are submicron plasma membrane-derived vesicles that express antigens of their cell of origin and phosphatidylserine (PS on their surface, facilitating their role in coagulation, inflammation and cell adhesion. In this study, the in vivo production, fate and pathogenicity of cell-specific MP during Plasmodium berghei infection of mice were evaluated. Using annexin V, a PS ligand, and flow cytometry, analysis of platelet-free plasma from infected mice with cerebral involvement showed a peak of MP levels at the time of the neurological onset. Phenotypic analyses showed that MP from infected mice were predominantly of platelet, endothelial and erythrocytic origins. To determine the in vivo fate of MP, we adoptively transferred fluorescently labelled MP from mice with CM into healthy or infected recipient mice. MP were quickly cleared following intravenous injection, but microscopic examination revealed arrested MP lining the endothelium of brain vessels of infected, but not healthy, recipient mice. To determine the pathogenicity of MP, we transferred MP from activated endothelial cells into healthy recipient mice and this induced CM-like brain and lung pathology. This study supports a pathogenic role for MP in the aggravation of the neurological lesion and suggests a causal relationship between MP and the development of CM.

  16. Dilepton production by dynamical quasiparticles in the strongly interacting quark gluon plasma

    CERN Document Server

    Linnyk, O

    2010-01-01

    The dilepton production by the constituents of the strongly interacting quark-gluon-plasma (sQGP) is addressed. In order to make quantitative predictions at realistically low plasma temperatures (O(T_c)), experimentally relevant low dilepton mass (O(1 GeV)) and strong coupling (alphaS=0.5-1), we take into account not only the higher order pQCD reaction mechanisms, but also the non-perturbative spectral functions (off-shellness) and self-energies of the quarks, anti-quarks and gluons thus going beyond the leading twist. For this purpose, our calculations utilize parametrizations of the non-perturbative propagators for quarks and gluons provided by the dynamical quasi-particle model (DQPM) matched to reproduce lattice data. The DQPM describes QCD properties in terms of single-particle Green's functions (in the sense of a two-particle irreducible approach) and leads to the notion of the constituents of the sQGP being effective quasiparticles, which are massive and have broad spectral functions (due to large inte...

  17. Intense positron beam as a source for production of electron-positron plasma

    Science.gov (United States)

    Stoneking, M. R.; Horn-Stanja, J.; Stenson, E. V.; Pedersen, T. Sunn; Saitoh, H.; Hergenhahn, U.; Niemann, H.; Paschkowski, N.; Hugenschmidt, C.; Piochacz, C.

    2016-10-01

    We aim to produce magnetically confined, short Debye length electron-positron plasma and test predicted properties for such systems. A first challenge is obtaining large numbers of positrons; a table-top experiment (system size 5 cm) with a temperature less than 5 eV requires about 1010 positrons to have more than 10 Debye lengths in the system. The NEPOMUC facility at the FRM II research reactor in Germany is one of the world's most intense positron sources. We report on characterization (using a retarding field energy analyzer with magnetic field gradient) of the NEPOMUC beam as delivered to the open beam port at various beam energies and in both the re-moderated and primary beam configurations in order to design optimal trapping (and accumulation) schemes for production of electron-positron plasma. The intensity of the re-moderated (primary) beam is in the range 2 -3 x 107 /s (1 - 5 x 108 /s). The re-moderated beam is currently the most promising for direct injection and confinement experiments; it has a parallel energy spread of 15 - 35% and the transverse energy spread is 6 - 15% of the parallel energy. We report on the implications for injection and trapping in a dipole magnetic field as well as plans for beam development, in situ re-moderation, and accumulation. We also report results demonstrating a difference in phosphor luminescent response to low energy positrons versus electrons.

  18. Steam Reforming of Dimethyl Ether by Gliding Arc Gas Discharge Plasma for Hydrogen Production

    Institute of Scientific and Technical Information of China (English)

    王保伟; 孙启梅; 吕一军; 杨美琳; 闫文娟

    2014-01-01

    Gliding arc gas discharge plasma was used for the generation of hydrogen from steam reforming of di-methyl ether (DME). A systemic procedure was employed to determine the suitable experimental conditions. It was found that DME conversion first increased up to the maximum and then decreased slightly with the increase of added water and air. The increase of total feed gas flow rate resulted in the decrease of DME conversion and hy-drogen yield, but hydrogen energy consumption dropped down to the lowest as total feed gas flow rate increased to 76 ml·min-1. Larger electrode gap and higher discharge voltage were advantageous. Electrode shape had an impor-tant effect on the conversion of DME and production of H2. Among the five electrodes, electrode 2# with valid length of 55 mm and the radian of 34 degrees of the top electrode section was the best option, which enhanced ob-viously the conversion of DME.

  19. Plasma separation process facility for large-scale stable isotope production

    Energy Technology Data Exchange (ETDEWEB)

    Bigelow, T.S.; Collins, E.D.; Tracy, J.G. [Oak Ridge National Lab., TN (United States)

    1997-12-01

    A facility for large-scale separation of stable isotopes using the plasma separation process (PSP) is under development at the Oak Ridge National Laboratory. The PSP is capable of separating isotopes at a large throughput rate with medium purity product and at relatively low cost. The PSP has a number of convenient features that make it an attractive technology for general isotope separation purposes. Several isotopes for medical and industrial applications, including {sup 102}Pd, {sup 98}Mo, {sup 203}Tl, {sup 184}W, and others, are expected to be processed in this facility. The large throughput and low processing cost of the PSP will likely lead to new applications for stable isotopes. A description of this facility and its typical throughput capability is presented here.

  20. Transport processes and entropy production in toroidal plasmas with gyrokinetic electromagnetic turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Sugama, H.; Okamoto, M.; Horton, W.; Wakatani, M.

    1996-01-01

    Transport processes and resultant entropy production in magnetically confined plasmas are studied in detail for toroidal systems with gyrokinetic electromagnetic turbulence. The kinetic equation including the turbulent fluctuations are double-averaged over the ensemble and the gyrophase. The entropy balance equation is derived from the double-averaged kinetic equation with the nonlinear gyrokinetic equation for the fluctuating distribution function. The result clarifies the spatial transport and local production of the entropy due to the classical, neoclassical and anomalous transport processes, respectively. For the anomalous transport process due to the electromagnetic turbulence as well as the classical and neoclassical processes, the kinetic form of the entropy production is rewritten as the thermodynamic form, from which the conjugate pairs of the thermodynamic forces and the transport fluxes are identified. The Onsager symmetry for the anomalous transport equations is shown to be valid within the quasilinear framework. The complete energy balance equation, which takes account of the anomalous transport and exchange of energy due to the fluctuations, is derived from the ensemble-averaged kinetic equation. The intrinsic ambipolarity of the anomalous particle fluxes is shown to hold for the self-consistent turbulent electromagnetic fields satisfying Poisson`s equation and Ampere`s law. (author).

  1. Absolute production rate measurements of nitric oxide by an atmospheric pressure plasma jet (APPJ)

    Energy Technology Data Exchange (ETDEWEB)

    Pipa, A V; Bindemann, T; Foest, R; Kindel, E; Roepcke, J; Weltmann, K-D [Leibniz-Institut fuer Plasmaforschung and Technologie e.V. (INP), Felix-Hausdorff Strasse 2, D-17489 Greifswald (Germany)], E-mail: foest@inp-greifswald.de

    2008-10-07

    Tunable diode laser absorption spectroscopy (TDLAS) has been applied to measure the absolute production rate of NO molecules in the gas phase of an atmospheric pressure plasma jet (APPJ) operating at rf (13.56 MHz) in argon with small (up to 1%) admixtures of air. The resulting NO production rates were found to be in the range (0.1-80) x 10{sup -3} sccm or (0.05-35) x 10{sup 18} molecules s{sup -1} depending on the experimental conditions. Maximum rates were obtained at 0.2% air. For TDLAS measurements the APPJ was arranged inside an astigmatic multi-pass cell of Herriott type with 100 m absorption length. The insertion into a closed volume differs slightly from the normal, open operation with the jet propagating freely into air. Therefore, the measuring results are compared with optical emission of the open jet to verify equivalent experimental conditions. The dependence of the optical emission of NO (237 nm) on power and gas mixture has been measured. The similar shape of the dependence of absorption and emission signals gives evidence that the comparability of experimental conditions is sufficiently satisfied. It is concluded that the NO production rate of the APPJ in ambient air can be characterized using TDLAS and provides reliable results in spite of differing experimental conditions due to the set-up.

  2. Phases formed during rapid quenching of liquid carbon

    Science.gov (United States)

    Basharin, A. Yu.; Dozhdikov, V. S.; Dubinchuk, V. T.; Kirillin, A. V.; Lysenko, I. Yu.; Turchaninov, M. A.

    2009-05-01

    Pulsed laser action upon a sample of highly oriented pyrolytic graphite (HOPG) in a gasostat filled with helium at a pressure above that corresponding to the triple point of carbon, followed by rapid quenching of the liquid phase at a rate of about 106 K/s leads to the formation of a crater with a periodic spatial structure at the surface. The composition and structure of nongraphite carbon phases in the near-surface region of the crater have been studied using the Raman scattering spectroscopy, electron microdiffraction, and energy-dispersive X-ray analysis. It is established that rapidly quenched carbon possesses predominantly a hybrid structure of glassy carbon formed as a result of the high-temperature treatment, with inclusions of crystalline carbyne, chaoite, and a hybrid cubic phase of ultradense carbon (C8). The hybrid phases of glassy carbon and C8 had not been reported until now as possible products of solidification of liquid carbon.

  3. Torus CLAS12-Superconducting Magnet Quench Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kashikhin, V S; Elouadhiri, L; Ghoshal, P K; Kashy, D; Makarov, A; Pastor, O; Quettier, L; Velev, G; Wiseman, M

    2014-06-01

    The JLAB Torus magnet system consists of six superconducting trapezoidal racetrack-type coils assembled in a toroidal configuration. These coils are wound with SSC-36 Nb-Ti superconductor and have the peak magnetic field of 3.6 T. The first coil manufacturing based on the JLAB design began at FNAL. The large magnet system dimensions (8 m diameter and 14 MJ of stored energy) dictate the need for quench protection. Each coil is placed in an aluminum case mounted inside a cryostat and cooled by 4.6 K supercritical helium gas flowing through a copper tube attached to the coil ID. The large coil dimensions and small cryostat thickness drove the design to challenging technical solutions, suggesting that Lorentz forces due to transport currents and eddy currents during quench and various failure scenarios are analyzed. The paper covers the magnet system quench analysis using the OPERA3d Quench code.

  4. Temperature Profiles During Quenches in LHC Superconducting Dipole Magnets Protected by Quench Heaters

    CERN Document Server

    Maroussov, V; Siemko, A

    2000-01-01

    The efficiency of the magnet protection by quench heaters was studied using a novel method which derives the temperature profile in a superconducting magnet during a quench from measured voltage signals. In several Large Hadron Collider single aperture dipole models, temperature profiles and temperature gradients in the magnet coil have been evaluated in the case of protection by different sets of quench heaters and different powering and protection parameters. The influence of the insulation thickness between the quench heaters and the coil has also been considered. The results show clear correlation between the positions of quench heaters, magnet protection parameters and temperature profiles. This study allowed a better understanding of the quench process mechanisms and the efficiency assessment of the different protection schemes.

  5. Quenching of photoluminescence of colloidal ZnO nanocrystals by nitronyl nitroxide radicals

    Energy Technology Data Exchange (ETDEWEB)

    Stroyuk, Oleksandr L., E-mail: stroyuk@inphyschem-nas.kiev.ua [L.V. Pysarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine, 31 Nauky avenue, 03028 Kyiv (Ukraine); Yakovenko, Anastasiya V.; Raevskaya, Oleksandra E. [L.V. Pysarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine, 31 Nauky avenue, 03028 Kyiv (Ukraine); Plyusnin, Victor F. [Institute of Chemical Kinetics and Combustion of Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2014-11-15

    Quenching of the photoluminescence of colloidal zinc oxide nanocrystals by a series of stable nitronyl nitroxide radicals was studied by means of stationary and time-resolved luminescence spectroscopy. Among the studied radicals the most efficient quenchers of the ZnO luminescence are the carboxyl-substituted species. The meta-substituted radical was found to be a more active quencher, than para-substituted one due to a closer proximity of the radical center to the nanocrystals surface. The PL quenching has a complex dynamic/static character. The dynamic quenching arises from photocatalytic radical reduction by ZnO conduction band electrons, while the static quenching is caused by adsorption of the photoreduction products on the nanocrystal surface. The non-substituted and OH-substituted radicals are inferior to the products of their photoreduction in capability of adsorption of the ZnO surface, and the quenching is dominated by interactions between the nanocrystals and photoreduced hydroxylamines. In case of COOH-substituted radicals, however, the radicals compete with the photoreduction products for the surface sites of ZnO nanocrystals resulting in a dynamic character of photoluminescence quenching.

  6. Electronic quenching of OH A 2Σ+ induced by collisions with Kr atoms.

    Science.gov (United States)

    Lehman, Julia H; Lester, Marsha I; Kłos, Jacek; Alexander, Millard H; Dagdigian, Paul J; Herráez-Aguilar, Diego; Aoiz, F Javier; Brouard, Mark; Chadwick, Helen; Perkins, Tom; Seamons, Scott A

    2013-12-19

    Electronic quenching of OH A (2)Σ(+) by Kr was investigated through experimental studies of the collision cross sections and the OH X (2)Π product state distribution. The quenching cross sections decrease with increasing rotational excitation in the excited OH A (2)Σ(+) electronic state. The OH X (2)Π products of quenching exhibit a significant degree of rotational excitation but minimal vibrational excitation. Complementary theoretical studies of the OH (A (2)Σ(+), X (2)Π) + Kr potential energy surfaces (PESs), nonadiabatic coupling, and quasiclassical trajectory calculations were carried out to elucidate the quenching dynamics. Accurate PESs for the two lowest diabatic states of A' symmetry were computed along with the angularly dependent coupling between them. Coupling in nearly linear HO-Kr configurations provides the mechanism for the observed electronic quenching. A deep attractive well on the OH A (2)Σ(+) + Kr PES facilitates access to this region of strong coupling. Surface-hopping quasiclassical trajectory calculations yielded quenching cross sections and a OH X (2)Π product rotational distribution in good accord with experimental observations.

  7. Fenofibrate increases very low density lipoprotein triglyceride production despite reducing plasma triglyceride levels in APOE*3-Leiden.CETP mice.

    Science.gov (United States)

    Bijland, Silvia; Pieterman, Elsbet J; Maas, Annemarie C E; van der Hoorn, José W A; van Erk, Marjan J; van Klinken, Jan B; Havekes, Louis M; van Dijk, Ko Willems; Princen, Hans M G; Rensen, Patrick C N

    2010-08-13

    The peroxisome proliferator-activated receptor alpha (PPARalpha) activator fenofibrate efficiently decreases plasma triglycerides (TG), which is generally attributed to enhanced very low density lipoprotein (VLDL)-TG clearance and decreased VLDL-TG production. However, because data on the effect of fenofibrate on VLDL production are controversial, we aimed to investigate in (more) detail the mechanism underlying the TG-lowering effect by studying VLDL-TG production and clearance using APOE*3-Leiden.CETP mice, a unique mouse model for human-like lipoprotein metabolism. Male mice were fed a Western-type diet for 4 weeks, followed by the same diet without or with fenofibrate (30 mg/kg bodyweight/day) for 4 weeks. Fenofibrate strongly lowered plasma cholesterol (-38%) and TG (-60%) caused by reduction of VLDL. Fenofibrate markedly accelerated VLDL-TG clearance, as judged from a reduced plasma half-life of glycerol tri[(3)H]oleate-labeled VLDL-like emulsion particles (-68%). This was associated with an increased post-heparin lipoprotein lipase (LPL) activity (+110%) and an increased uptake of VLDL-derived fatty acids by skeletal muscle, white adipose tissue, and liver. Concomitantly, fenofibrate markedly increased the VLDL-TG production rate (+73%) but not the VLDL-apolipoprotein B (apoB) production rate. Kinetic studies using [(3)H]palmitic acid showed that fenofibrate increased VLDL-TG production by equally increasing incorporation of re-esterified plasma fatty acids and liver TG into VLDL, which was supported by hepatic gene expression profiling data. We conclude that fenofibrate decreases plasma TG by enhancing LPL-mediated VLDL-TG clearance, which results in a compensatory increase in VLDL-TG production by the liver.

  8. The surprising inefficiency of dwarf satellite quenching

    CERN Document Server

    Wheeler, Coral; Cooper, Michael C; Boylan-Kolchin, Mike; Bullock, James S

    2014-01-01

    We study dwarf satellite galaxy quenching using observations from the Geha et al. (2012) NSA/SDSS catalog together with LCDM cosmological simulations to facilitate selection and interpretation. We show that fewer than 30% of dwarfs (M* ~ 10^8.5-10^9.5 Msun) identified as satellites within massive host halos (Mhost ~ 10^12.5-10^14 Msun) are quenched, in spite of the expectation from simulations that half of them should have been accreted more than 6 Gyr ago. We conclude that whatever the action triggering environmental quenching of dwarf satellites, the process must be highly inefficient. We investigate a series of simple, one-parameter quenching models in order understand what is required to explain the low quenched fraction and conclude that either the quenching timescale is very long (> 9.5 Gyr, a "slow starvation" scenario) or that the environmental trigger is not well matched to accretion within the virial volume. We discuss these results in light of the fact that most of the low mass dwarf satellites in ...

  9. Angular Structure of Jet Quenching Within a Hybrid Strong/Weak Coupling Model

    CERN Document Server

    Casalderrey-Solana, Jorge; Milhano, Guilherme; Pablos, Daniel; Rajagopal, Krishna

    2017-01-01

    Within the context of a hybrid strong/weak coupling model of jet quenching, we study the modification of the angular distribution of the energy within jets in heavy ion collisions, as partons within jet showers lose energy and get kicked as they traverse the strongly coupled plasma produced in the collision. To describe the dynamics transverse to the jet axis, we add the effects of transverse momentum broadening into our hybrid construction, introducing a parameter $K\\equiv \\hat q/T^3$ that governs its magnitude. We show that, because of the quenching of the energy of partons within a jet, even when $K\

  10. Angular Structure of Jet Quenching Within a Hybrid Strong/Weak Coupling Model

    CERN Document Server

    Casalderrey-Solana, Jorge; Milhano, Guilherme; Pablos, Daniel; Rajagopal, Krishna

    2016-01-01

    Within the context of a hybrid strong/weak coupling model of jet quenching, we study the modification of the angular distribution of the energy within jets in heavy ion collisions, as partons within jet showers lose energy and get kicked as they traverse the strongly coupled plasma produced in the collision. To describe the dynamics transverse to the jet axis, we add the effects of transverse momentum broadening into our hybrid construction, introducing a parameter $K\\equiv \\hat q/T^3$ that governs its magnitude. We show that, because of the quenching of the energy of partons within a jet, even when $K\

  11. Biodiesel production using fatty acids from food industry waste using corona discharge plasma technology.

    Science.gov (United States)

    Cubas, A L V; Machado, M M; Pinto, C R S C; Moecke, E H S; Dutra, A R A

    2016-01-01

    This article aims to describe an alternative and innovative methodology to transform waste, frying oil in a potential energy source, the biodiesel. The biodiesel was produced from fatty acids, using a waste product of the food industry as the raw material. The methodology to be described is the corona discharge plasma technology, which offers advantages such as acceleration of the esterification reaction, easy separation of the biodiesel and the elimination of waste generation. The best conditions were found to be an oil/methanol molar ratio of 6:1, ambient temperature (25 °C) and reaction time of 110 min and 30 mL of sample. The acid value indicates the content of free fatty acids in the biodiesel and the value obtained in this study was 0.43 mg KOH/g. Peaks corresponding to octadecadienoic acid methyl ester, octadecanoic acid methyl ester and octadecenoic acid methyl ester, from the biodiesel composition, were identified using GC-MS. A major advantage of this process is that the methyl ester can be obtained in the absence of chemical catalysts and without the formation of the co-product (glycerin). Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Advanced oxidation protein products in plasma: stability during storage and correlation with other clinical characteristics.

    Science.gov (United States)

    Matteucci, E; Biasci, E; Giampietro, O

    2001-12-01

    Proteins are susceptible to free radical damage. We measured advanced oxidation protein products (AOPP) in the plasma of 56 hospitalised patients. Concentrations of AOPP were expressed as chloramine-T equivalents by measuring absorbance in acidic conditions at 340 nm in the presence of potassium iodide. We also determined erythrocyte sedimentation rate (ESR), circulating urea, creatinine, glucose, uric acid, electrolytes, lipids, total proteins and fractions and fibrinogen. Twenty-four samples were processed both immediately and after 7, 15, 30, 90, 180 and 438 days of storage at both at -20 degrees C and -80 degrees C (aliquots were frozen and thawed only once) to evaluate AOPP stability. The remaining 32 samples were also processed for thiobarbituric-acid-reactive substances (TBARS). Mean AOPP concentration in all 56 patients was 48.3+/-37.2 microM. Mean basal concentration of AOPP in the 24 plasma samples (55.0+/-47.1 microM) showed no significant change at each intermediate determination, yet significantly increased after 438 days of storage both at -80 degrees C (96.6+/-83.2, p<0.01) and, markedly, at -20 degrees C (171.3+/-94.6, p<0.001). TBARS concentration was 1.59+/-0.65 micromol/l. Multiple regression analysis evidenced that AOPP concentration was positively correlated (multiple r=0.62, p<0.001) with serum urea and triglycerides, but negatively correlated with patient age (indeed, serum albumin and total proteins decreased with increasing age, r=0.3, p<0.05). TBARS concentration was associated with ESR and serum glucose (multiple r=0.73, p<0.001), yet positively with AOPP (r=0.39, simple p<0.05). We conclude that AOPP remain stable during sample storage both at -20 degrees C and -80 degrees C for 6 months. Renal failure and hypertriglyceridemia probably enhance the in vivo process of AOPP formation. Oxidative damage as measured by TBARS may be increased because of exposure to hyperglycemia causing nonenzymatic glycation of plasma proteins.

  13. Secondary Heating Under Quenching Cooling of Aluminum Alloys

    Science.gov (United States)

    Tsukrov, S. L.; Ber, L. B.

    2017-07-01

    Variants of secondary heating of aluminum alloys are considered, i.e., under quenching of plates in a water tank or on a horizontal quenching unit with water jet cooling, under continuous quenching of strips, and under quenching of tubes in vertical furnaces. Recommendation are given for removal or substantial reduction of the intensity of secondary heating under industrial conditions.

  14. Dilepton production as a useful probe of quark gluon plasma with temperature dependent chemical potential quark mass

    Science.gov (United States)

    Kumar, Yogesh; Singh, S. Somorendro

    2016-07-01

    We extend the previous study of dilepton production using [S. Somorendro Singh and Y. Kumar, Can. J. Phys. 92 (2014) 31] based on a simple quasiparticle model of quark-gluon plasma (QGP). In this model, finite value of quark mass uses temperature dependent chemical potential the so-called Temperature Dependent Chemical Potential Quark Mass (TDCPQM). We calculate dilepton production in the relevant range of mass region. It is observed that the production rate is marginally enhanced from the earlier work. This is due to the effect of TDCPQM and its effect is highly significant in the production of dilepton.

  15. On jet quenching parameters in strongly coupled non-conformal gauge theories

    CERN Document Server

    Buchel, A

    2006-01-01

    Recently Liu, Rajagopal and Wiedemann (LRW) [hep-ph/0605178] proposed a first principle, nonperturbative quantum field theoretic definition of ``jet quenching parameter'' \\hat{q} used in models of medium-induced radiative parton energy loss in nucleus-nucleus collisions at RHIC. Relating \\hat{q} to a short-distance behavior of a certain light-like Wilson loop, they used gauge theory-string theory correspondence to evaluate \\hat{q} for the strongly coupled N=4 SU(N_c) gauge theory plasma. We generalize analysis of LRW to strongly coupled non-conformal gauge theory plasma. We find that a jet quenching parameter is gauge theory specific (not universal). Furthermore, it appears it's value increases as the number of effective adjoint degrees of freedom of a gauge theory plasma increases.

  16. Fenofibrate increases very low density lipoprotein triglyceride production despite reducing plasma triglyceride levels in APOE*3-Leiden.CETP mice

    NARCIS (Netherlands)

    Bijland, S.; Pieterman, E.J.; Maas, A.C.E.; Hoorn, J.W.A. van der; Erk, M.J. van; Klinken, J.B. van; Havekes, L.M.; Dijk, K.W. van; Princen, H.M.G.; Rensen, P.C.N.

    2010-01-01

    The peroxisome proliferator-activated receptor alpha (PPARα) activator fenofibrate efficiently decreases plasma triglycerides (TG), which is generally attributed to enhanced very low density lipoprotein (VLDL)-TG clearance and decreased VLDL-TG production. However, because data on the effect of feno

  17. Synthesis of ZnO particles in a quench-cooled flame reactor

    DEFF Research Database (Denmark)

    Hansen, Jens Peter; Jensen, Joakim Reimer; Livbjerg, Hans

    2001-01-01

    . At the highest tested production rate, the specific surface area of the ZnO particles increases from 20 to 60 m(2)/g when quenching is employed. The particles are characterized by BET surface area measurements, TEM images, and the size distributions of particle aggregates are measured by a scanning mobility......The quench cooling of a flame by injection of cold air was studied in a flame reactor for the formation of ZnO particles in a premixed flame with a precursor jet. A rapid temperature drop downstream from the temperature peak is advantageous for the attainment of a large specific surface area....... Computational fluid dynamics simulations were used to design a quench ring with nozzles directed slightly upward and at a small tangential angle from the direct line to the center. This novel design avoids distortion of the flow pattern below the quenching plane and effectively cools the flame immediately above...

  18. Photon Production in a Chemically Equilibrating Quark-Gluon Plasma at Finite Baryon Density: Complete Leading Order Results

    Institute of Scientific and Technical Information of China (English)

    LONG Jia-Li; HE Ze-Jun; MA Yu-Gang

    2006-01-01

    @@ We investigate hard photon production of the near-collinear bremsstrahlung and a new process called the inelastic pair annihilation, fully including the LPM effect, in a chemically equilibrating quark-gluon plasma at finite baryon density, and find that the effect of the system evolution on the photon production and large contribution of the bremsstrahlung make the total photon yield of the two processes as a strongly increasing function of the initial quark chemical potential.

  19. Danger signal-dependent activation of human dendritic cells by plasma-derived factor VIII products.

    Science.gov (United States)

    Miller, L; Weissmüller, S; Ringler, E; Crauwels, P; van Zandbergen, G; Seitz, R; Waibler, Z

    2015-08-01

    Treatment of haemophilia A by infusions of the clotting factor VIII (FVIII) results in the development of inhibitors/anti-drug antibodies in up to 25 % of patients. Mechanisms leading to immunogenicity of FVIII products are not yet fully understood. Amongst other factors, danger signals as elicited upon infection or surgery have been proposed to play a role. In the present study, we focused on effects of danger signals on maturation and activation of dendritic cells (DC) in the context of FVIII application. Human monocyte-derived DC were treated with FVIII alone, with a danger signal alone or a combination of both. By testing more than 60 different healthy donors, we show that FVIII and the bacterial danger signal lipopolysaccharide synergise in increasing DC activation, as characterised by increased expression of co-stimulatory molecules and secretion of pro-inflammatory cytokines. The degree and frequency of this synergistic activation correlate with CD86 expression levels on immature DC prior to stimulation. In our assay system, plasma-derived but not recombinant FVIII products activate human DC in a danger signal-dependent manner. Further tested danger signals, such as R848 also induced DC activation in combination with FVIII, albeit not in every tested donor. In our hands, human DC but not human B cells or macrophages could be activated by FVIII in a danger signal-dependent manner. Our results suggest that immunogenicity of FVIII is a result of multiple factors including the presence of danger, predisposition of the patient, and the choice of a FVIII product for treatment.

  20. Effect of radicals combination on acetylene yield in process of coal pyrolysis by hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Dai, B.; Fan, Y.; Yang, J.; Xiao, J. [Tsinghua University, Beijing (China). Dept. of Engineering Mechanics

    1999-07-01

    A new process for production of acetylene by pyrolysis of coal in hydrogen plasma overcomes the disadvantage of discontinuity and pollution in the conventional carbide method. Complex homogeneous reactions take place after pulverized coal is injected into a high-temperature plasma reactor. In order to preserve C{sub 2}H{sub 2} in low-temperature gas, quenching is needed to avoid the dissociation of acetylene. The objective of this paper is to indicate that radicals recombination is also important in acetylene production. Therefore the quenching process should be optimized to obtain high yield of acetylene. In this work, C-H equilibrium system in high-temperature range of 2000-5000 K is obtained using the free energy minimization method. At lower temperature, the decomposition of acetylene can be avoided while the recombination reaction of radicals C{sub 2}H and H will not be interrupted. As a result, the acetylene concentration in quenched gas will increase. The theoretical acetylene content in quenched gas is computed using the radical recombination mechanism based on the composition of thermal equilibrium, and the optimized C/H ratio is determined simultaneously. The maximum acetylene content is 59.9% in volume. 4 refs., 3 figs., 1 tab.

  1. Effects of quenching and partial quenching on QCD penguin matrix elements

    NARCIS (Netherlands)

    Golterman, Maarten; Pallante, Elisabetta

    2002-01-01

    We point out that chiral transformation properties of penguin operators change in the transition from unquenched to (partially) quenched QCD. The way in which this affects the lattice determination of weak matrix elements can be understood in the framework of (partially) quenched chiral perturbation

  2. Quench absorption coils: a quench protection concept for high-field superconducting accelerator magnets

    Science.gov (United States)

    Mentink, M.; Salmi, T.

    2017-06-01

    A quench protection concept based on coupled secondary coils is studied for inductively transferring energy out of a quenching superconducting dipole and thus limiting the peak hotspot temperature. So-called ‘quench absorption coils’ are placed in close proximity to the superconducting coils and are connected in series with a diode for the purpose of preventing current transformation during regular operation. During a quench, current is then transformed into the quench absorption coils so that a significant fraction of the stored magnetic energy is dissipated in the these coils. Numerical calculations are performed to determine the impact of such a concept and to evaluate the dimensions of the quench absorption coils needed to obtain significant benefits. A previously constructed 15 T Nb3Sn block coil is taken as a reference layout. Finite-element calculations are used to determine the combined inductive and thermal response of this system and these calculations are validated with a numerical model using an adiabatic approximation. The calculation results indicate that during a quench the presence of the quench absorption coils reduces the energy dissipated in the superconducting coils by 45% and reduces the hotspot temperature by over 100 K. In addition, the peak resistive voltage over the superconducting coils is significantly reduced. This suggests that this concept may prove useful for magnet designs in which the hotspot temperature is a design driver.

  3. Nano powders, components and coatings by plasma technique

    Science.gov (United States)

    McKechnie, Timothy N. (Inventor); Antony, Leo V. M. (Inventor); O'Dell, Scott (Inventor); Power, Chris (Inventor); Tabor, Terry (Inventor)

    2009-01-01

    Ultra fine and nanometer powders and a method of producing same are provided, preferably refractory metal and ceramic nanopowders. When certain precursors are injected into the plasma flame in a reactor chamber, the materials are heated, melted and vaporized and the chemical reaction is induced in the vapor phase. The vapor phase is quenched rapidly to solid phase to yield the ultra pure, ultra fine and nano product. With this technique, powders have been made 20 nanometers in size in a system capable of a bulk production rate of more than 10 lbs/hr. The process is particularly applicable to tungsten, molybdenum, rhenium, tungsten carbide, molybdenum carbide and other related materials.

  4. Acrylamide-quenching of Rhizomucor miehei lipase.

    Science.gov (United States)

    Stobiecka, Agnieszka

    2005-07-01

    Steady-state and time-resolved fluorescence-quenching measurements have been performed to study multitryptophan lipase from filamentous fungus Rhizomucor miehei. Using the steady-state acrylamide fluorescence quenching data and the fluorescence-quenching-resolved-spectra (FQRS) method, the total emission spectrum of native ("closed-lid") lipase has been decomposed into two distinct spectral components accessible to acrylamide. According to FQRS analysis, more quenchable component has a maximum of fluorescence emission at about 352 nm whereas less quenchable component emits at about 332 nm. The redder component participates in about 60-64% of the total lipase fluorescence and may be characterized by the dynamic and static quenching constants equal to K(1) = 3.75 M(-1) and V(1) = 1.12 M(-1), respectively. The bluer component is quenchable via dynamic mechanism with K(2) = 1.97 M(-1). Significant difference in the values of acrylamide bimolecular rate quenching constants estimated for redder and bluer component (i.e., k(q) = 1.2 x 10 (9) M(-1)s (-1) vs. k(q) = 4.3 x 10(8) M(-1) s(-1), respectively), suggests that tryptophan residues in fungal lipase are not uniformly exposed to the solvent.

  5. Topological blocking in quantum quench dynamics

    Science.gov (United States)

    Kells, G.; Sen, D.; Slingerland, J. K.; Vishveshwara, S.

    2014-06-01

    We study the nonequilibrium dynamics of quenching through a quantum critical point in topological systems, focusing on one of their defining features: ground-state degeneracies and associated topological sectors. We present the notion of "topological blocking," experienced by the dynamics due to a mismatch in degeneracies between two phases, and we argue that the dynamic evolution of the quench depends strongly on the topological sector being probed. We demonstrate this interplay between quench and topology in models stemming from two extensively studied systems, the transverse Ising chain and the Kitaev honeycomb model. Through nonlocal maps of each of these systems, we effectively study spinless fermionic p-wave paired topological superconductors. Confining the systems to ring and toroidal geometries, respectively, enables us to cleanly address degeneracies, subtle issues of fermion occupation and parity, and mismatches between topological sectors. We show that various features of the quench, which are related to Kibble-Zurek physics, are sensitive to the topological sector being probed, in particular, the overlap between the time-evolved initial ground state and an appropriate low-energy state of the final Hamiltonian. While most of our study is confined to translationally invariant systems, where momentum is a convenient quantum number, we briefly consider the effect of disorder and illustrate how this can influence the quench in a qualitatively different way depending on the topological sector considered.

  6. Production performance and plasma metabolites of dairy ewes in early lactation as affected by chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Rodriguez, A.; Arranz, J.; Mandaluniz, N.; Beltrán-de-Heredia, I.; Ruiz, R.; Goiri, I.

    2015-07-01

    The objective of this study was to evaluate the effects of chitosan (CHI) supplementation on production performance and blood parameters in dairy ewes. Twenty-four multiparous Latxa dairy ewes at d 16 of lactation were divided into two groups of 12 ewes each. Ewes were fed one of two experimental concentrates (0.840 kg dry matter/d), control or supplemented with 1.2% CHI, on a dry matter basis. Ewes also had free access to tall fescue hay, water, and mineral salts. The experimental period lasted for 25 d, of which the first 14 d were for treatment adaptation and the last 11 d for measurements and samplings. Supplementation with CHI decreased total (p=0.043) and fescue (p=0.035) dry matter intake (DMI), but did not affect concentrate DMI. Supplementation with CHI, moreover, increased plasma glucose (p=0.013) and BUN concentrations (p=0.035), but did not affect those of non-esterified fatty acids. Dietary supplementation with CHI, however, did not affect milk yield, 6.5% FCM, milk composition, or BW, but it improved dietary apparent efficiency by increasing the milk yield-to-DMI (p=0.055) and 6.5% FCM-to-DMI (p=0.045) ratios. In conclusion, dietary supplementation of chitosan maintained ewe performance while reducing feed intake and improving dietary apparent efficiency. (Author)

  7. Effects of fat supplementations on milk production and composition, ruminal and plasma parameters of dairy cows

    Directory of Open Access Journals (Sweden)

    L. Bailoni

    2010-04-01

    Full Text Available The effects on milk yield and quality caused by the same amount (325 g/d/cow of lipids provided by 3 different fat sources (hydrogenate palm fat, HF; calcium salt palm fat, CaSF; full-fat toasted soybean, TS, top dressed to a common total mixed ration, were investigated. Supplementations did not affect feed intake and milk yield, but markedly changed the acidic profile of milk fat. CaSF and TS significantly increased the proportions of unsaturated fatty acids of milk fat with respect to control and to HF. The 3 fat sources did not affect the concentrations of ammonia and VFA of rumen fluid. TS only slightly increased (P<0.10 plasma urea content because of a higher dietary protein supply, with respect to the other treatments. The use of a low amount of toasted and cracked full fat soybean seem to be interesting to increase the energy concentration of diets in replacement to commercial fat products and it can be use to modify the milk fat quality increasing the fraction with benefit effects on human health.

  8. A feature of negative hydrogen ion production in the Uramoto-type sheet plasma

    Energy Technology Data Exchange (ETDEWEB)

    Jimbo, Kouichi [Kyoto Univ., Uji (Japan). Inst. of Atomic Energy

    1997-02-01

    It seems that negative hydrogen ions H{sup -} are formed directly from atomic hydrogens H. When the chamber was biased more negative against the anode potential at constant are power, forming a much deeper electrostatic well in the Uramoto-type sheet plasma negative ion source, more negative hydrogen ion currents were extracted. The chamber potential V{sub B} was biased down to -100V in the 150V discharge. The negative ion current J{sup -} was evaluated by the JAERI-probe measurement. J{sup -} increases linearly with the chamber current I{sub B}. The largest J{sup -} value was obtained at absolute value of |V{sub prob,f}|=15V and absolute value of |V{sub B}|=100V; the discharge was not operated for absolute value of |V{sub B}|>100V. We speculate the following collisional (three-body) electron attachment to H as a possible production process for H{sup -}; e+e+H{yields}e+H{sup -}. This process may explain the linear increase of J{sup -} with absolute value of |V{sub prob,f}|. (S.Y.)

  9. Aerosol emission monitoring in the production of silicon carbide nanoparticles by induction plasma synthesis

    Science.gov (United States)

    Thompson, Drew; Leparoux, Marc; Jaeggi, Christian; Buha, Jelena; Pui, David Y. H.; Wang, Jing

    2013-12-01

    In this study, the synthesis of silicon carbide (SiC) nanoparticles in a prototype inductively coupled thermal plasma reactor and other supporting processes, such as the handling of precursor material, the collection of nanoparticles, and the cleaning of equipment, were monitored for particle emissions and potential worker exposure. The purpose of this study was to evaluate the effectiveness of engineering controls and best practice guidelines developed for the production and handling of nanoparticles, identify processes which result in a nanoparticle release, characterize these releases, and suggest possible administrative or engineering controls which may eliminate or control the exposure source. No particle release was detected during the synthesis and collection of SiC nanoparticles and the cleaning of the reactor. This was attributed to most of these processes occurring in closed systems operated at slight underpressure. Other tasks occurring in more open spaces, such as the disconnection of a filter assembly from the reactor system and the use of compressed air for the cleaning of filters where synthesized SiC nanoparticles were collected, resulted in releases of submicrometer particles with a mode size of 170-180 nm. Observation of filter samples under scanning electron microscope confirmed that the particles were agglomerates of SiC nanoparticles.

  10. Production and clearance of plasma triacylglycerols in ponies fed diets containing either medium-chain triacylglycerols or soya bean oil.

    Science.gov (United States)

    Hallebeek, J M; Beynen, A C

    2003-06-01

    The hypothesis was tested that feeding ponies a diet containing medium-chain triacylglcyerols (MCT) instead of soya bean oil causes an increase in the production of plasma triacylglycerols, which, under steady-state conditions, is associated with an increased clearance of triacylglycerols. Six ponies were fed rations containing either MCT or an isoenergetic amount of soya bean oil according to a cross-over design. The concentration of MCT in the total dietary dry matter was about 13%. When the ponies were fed the diets for 3 weeks, plasma triacylglycerol concentrations were 0.42 +/- 0.09 and 0.17 +/- 0.03 mmol/l (mean +/- SE, n = 6; p bean-oil treatment, respectively. Plasma triacylglycerol production was assessed using the Triton method and clearance with the use of Intralipid(R) infusion. Plasma triacylglycerol production was 2.91 +/- 0.88 and 0.50 +/- 0.14 micromol/l.min (means +/- SE, n = 4; p bean oil, respectively. It is suggested that the calculated rates of triacylglycerol production are underestimated, the deviation being greatest when the ponies were fed the ration of soya bean oil. Triacylglycerol clearance rates were calculated on the basis of group mean values for both the fractional clearance rate and the baseline levels of plasma triacylglycerols; the values were 4.28 and 3.52 micromol/l.min for MCT and soya bean oil feeding, respectively. The mean, absolute clearance rates as based on those found in individual ponies did not show an increase when the diet with MCT was fed. Nevertheless, it is concluded that the data obtained support our hypothesis.

  11. Thermal quench at finite 't Hooft coupling

    Directory of Open Access Journals (Sweden)

    H. Ebrahim

    2016-03-01

    Full Text Available Using holography we have studied thermal electric field quench for infinite and finite 't Hooft coupling constant. The set-up we consider here is D7-brane embedded in (α′ corrected AdS-black hole background. It is well-known that due to a time-dependent electric field on the probe brane, a time-dependent current will be produced and it will finally relax to its equilibrium value. We have studied the effect of different parameters of the system on equilibration time. As the most important results, for massless fundamental matter, we have observed a universal behaviour in the rescaled equilibration time in the very fast quench regime for different values of the temperature and α′ correction parameter. It seems that in the slow quench regime the system behaves adiabatically. We have also observed that the equilibration time decreases in finite 't Hooft coupling limit.

  12. Dynamical quenching of tunneling in molecular magnets

    Energy Technology Data Exchange (ETDEWEB)

    José Santander, María, E-mail: maria.jose.noemi@gmail.com [Recursos Educativos Quántica, Santiago (Chile); Departamento de Física, Universidad de Santiago de Chile and CEDENNA, Avda. Ecuador 3493, Santiago (Chile); Nunez, Alvaro S., E-mail: alnunez@dfi.uchile.cl [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Casilla 487-3, Santiago (Chile); Roldán-Molina, A. [Instituto de Física, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Curauma, Valparaíso (Chile); Troncoso, Roberto E., E-mail: r.troncoso.c@gmail.com [Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Avda. Ecuador 3493, Santiago 9170124 (Chile); Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso (Chile)

    2015-12-15

    It is shown that a single molecular magnet placed in a rapidly oscillating magnetic field displays the phenomenon of quenching of tunneling processes. The results open a way to manipulate the quantum states of molecular magnets by means of radiation in the terahertz range. Our analysis separates the time evolution into slow and fast components thereby obtaining an effective theory for the slow dynamics. This effective theory presents quenching of the tunnel effect, in particular, stands out its difference with the so-called coherent destruction of tunneling. We support our prediction with numerical evidence based on an exact solution of Schrödinger's equation. - Highlights: • Single molecular magnets under rapidly oscillating magnetic fields is studied. • It is shown that this system displays the quenching of tunneling processes. • Our findings provide a control of quantum molecular magnets via terahertz radiation.

  13. Jet Quenching and Holographic Thermalization with a Chemical Potential

    CERN Document Server

    Caceres, Elena; Yang, Di-Lun

    2012-01-01

    We investigate jet quenching of virtual gluons and thermalization of a strongly-coupled plasma with a non-zero chemical potential via the gauge/gravity duality. By tracking a charged shell falling in an asymptotic AdS$_{d+1}$ background for $d=3$ and $d=4$, which is characterized by the AdS-Reissner-Nordstr\\"om-Vaidya (AdS-RN-Vaidya) geometry, we extract a thermalization time of the medium with a non-zero chemical potential. In addition, we study the falling string as the holographic dual of a virtual gluon in the AdS-RN-Vaidya spacetime. The stopping distance of the massless particle representing the tip of the falling string in such a spacetime could reveal the jet quenching of an energetic light probe traversing the medium in the presence of a chemical potential. We find that the stopping distance decreases when the chemical potential is increased in both AdS-RN and AdS-RN-Vaidya spacetimes, which correspond to the thermalized and thermalizing media respectively. Moreover, we find that the soft gluon with ...

  14. Quench in high temperature superconductor magnets

    CERN Document Server

    Schwartz, J

    2013-01-01

    High field superconducting magnets using high temperature superconductors are being developed for high energy physics, nuclear magnetic resonance and energy storage applications. Although the conductor technology has progressed to the point where such large magnets can be readily envisioned, quench protection remains a key challenge. It is well-established that quench propagation in HTS magnets is very slow and this brings new challenges that must be addressed. In this paper, these challenges are discussed and potential solutions, driven by new technologies such as optical fiber based sensors and thermally conducting electrical insulators, are reviewed.

  15. Quench propagation analysis in adiabatic superconducting windings

    Energy Technology Data Exchange (ETDEWEB)

    Ishiyama, A.; Matsumura, H.; Takita, W. (Dept. of Electrical Engineering, Waseda Univ., Tokyo (JP)); Iwasa, Y (Massachusetts Inst. of Tech., Cambridge, MA (United States). Francis Bitter National Magnet Lab.)

    1991-03-01

    This paper reports the basic postulate of the author's quench simulation code, developed to analyze normal-zone propagation in adiabatic magnets which is the code's computation may be immensely simplified without sacrifice in accuracy by aggregating all thermal properties of the winding affecting normal-zone propagation into a single parameter of the transverse quench velocity. In order to verify this postulate, a finite element method (FEM) analysis has been applied to solve the temporal and spatial evolution of temperature within a section of an adiabatic magnet winding.

  16. Event-Shape Engineering and Jet Quenching

    CERN Document Server

    Christiansen, Peter

    2016-01-01

    Event-Shape Engineering (ESE) is a tool that enables some control of the initial geometry in heavy-ion collisions in a similar way as the centrality enables some control of the number of participants. Utilizing ESE, the path length in and out-of plane can be varied while keeping the medium properties (centrality) fixed. In this proceeding it is argued that this provides additional experimental information about jet quenching. Finally, it is suggested that if ESE studies are done in parallel for light and heavy quarks one can determine, in a model independent way, if the path-length dependence of their quenching differs.

  17. Changes in cellular proliferation and plasma products are associated with liver failure

    Science.gov (United States)

    Melgaço, Juliana Gil; Soriani, Frederico Marianetti; Sucupira, Pedro Henrique Ferreira; Pinheiro, Leonardo Assaf; Vieira, Yasmine Rangel; de Oliveira, Jaqueline Mendes; Lewis-Ximenez, Lia Laura; Araújo, Cristina Carvalho Vianna; Pacheco-Moreira, Lúcio Filgueiras; Menezes, Gustavo Batista; Cruz, Oswaldo Gonçalves; Vitral, Claudia Lamarca; Pinto, Marcelo Alves

    2016-01-01

    AIM To study the differences in immune response and cytokine profile between acute liver failure and self-limited acute hepatitis. METHODS Forty-six patients with self-limited acute hepatitis (AH), sixteen patients with acute liver failure (ALF), and twenty-two healthy subjects were involved in this study. The inflammatory and anti-inflammatory products in plasma samples were quantified using commercial enzyme-linked immunoassays and quantitative real-time PCR. The cellular immune responses were measured by proliferation assay using flow cytometry. The groups were divided into viral- and non-viral-induced self-limited AH and ALF. Thus, we worked with five groups: Hepatitis A virus (HAV)-induced self-limited acute hepatitis (HAV-AH), HAV-induced ALF (HAV-ALF), non-viral-induced self-limited acute hepatitis (non-viral AH), non-viral-induced acute liver failure (non-viral ALF), and healthy subjects (HC). Comparisons among HAV and non-viral-induced AH and ALF were performed. RESULTS The levels of mitochondrial DNA (mtDNA) and the cytokines investigated [interleukin (IL)-6, IL-8, IL-10, interferon gamma, and tumor necrosis factor] were significantly increased in ALF patients, independently of etiology (P < 0.05). High plasma mtDNA and IL-10 were the best markers associated with ALF [mtDNA: OR = 320.5 (95%CI: 14.42-7123.33), P < 0.0001; and IL-10: OR = 18.8 (95%CI: 1.38-257.94), P = 0.028] and death [mtDNA: OR = 12.1 (95%CI: 2.57-57.07), P = 0.002; and IL-10: OR = 8.01 (95%CI: 1.26-50.97), P = 0.027]. In the cellular proliferation assay, NKbright, NKT and regulatory T cells (TReg) predominated in virus-specific stimulation in HAV-induced ALF patients with an anergic behavior in the cellular response to mitotic stimulation. Therefore, in non-viral-induced ALF, anergic behavior of activated T cells was not observed after mitotic stimulation, as expected and as described by the literature. CONCLUSION mtDNA and IL-10 may be predictors of ALF and death. TReg cells are

  18. Fluorescence quenching of TMR by guanosine in oligonucleotides

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Nucleotide-specific fluorescence quenching in fluorescently labeled DNA has many applications in biotechnology. We have studied the inter-and intra-molecular quenching of tetramethylrhodamine (TMR) by nucleotides to better understand their quenching mechanism and influencing factors. In agreement with previous work, dGMP can effectively quench TMR, while the quenching of TMR by other nucleotides is negligible. The Stern-Volmer plot between TMR and dGMP delivers a bimolecular quenching constant of Ks=52.3 M-1. The fluorescence of TMR in labeled oligonucleotides decreases efficiently through photoinduced electron transfer by guanosine. The quenching rate constant between TMR and guanosine was measured using fluorescence correlation spectroscopy (FCS). In addition, our data show that the steric hindrance by bases around guanosine has significant effect on the G-quenching. The availability of these data should be useful in designing fluorescent oligonucleotides and understanding the G-quenching process.

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

    NARCIS (Netherlands)

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

    2010-01-01

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

  20. The optimization of production and control of hot-electron plasmas

    Energy Technology Data Exchange (ETDEWEB)

    1988-03-11

    The research discussed in this paper consist of the following: Hot-Electron Plasma Formation in AMPHED; Kinectic Models of Hot-Electron Plasma Formation; Resonator Design and Tests; Results of 1-D Fokker-Planck ECH Study of TEXT; and AMPC/TEXT Collaboration.

  1. The use of laser-induced shock wave plasma spectroscopy (LISPS) for examining physical characteristics of pharmaceutical products

    Energy Technology Data Exchange (ETDEWEB)

    Abdulmadjid, Syahrun Nur, E-mail: syahrun-madjid@yahoo.com; Lahna, Kurnia, E-mail: kurnialahna@gmail.com [Department of Physics, Faculty of Mathematics and Natural Sciences, Syiah Kuala University, Darussalam, Banda Aceh 23111, Aceh (Indonesia); Desiyana, Lydia Septa, E-mail: lydia-septa@yahoo.com [Department of Pharmacy, Faculty of Mathematics and Natural Sciences, Syiah Kuala University, Darussalam, Banda Aceh 23111, Aceh (Indonesia)

    2016-03-11

    An experimental study has been performed to examine the physical characteristics of pharmaceutical products, such as tablet, by employing an emission plasma induced by Nd-YAG laser at a low pressure of Helium gas. The hardness of tablet is one of the parameters that examined during the production process for standard quality of pharmaceutical products. In the Laser-Induced Shock Wave Plasma Spectroscopy (LISPS), the shock wave has a significant role in inducing atomic excitation. It was known that, the speed of the shock wavefront depends on the hardness of the sample, and it correlates with the ionization rate of the ablated atoms. The hardness of the tablet is examined using the intensity ratio between the ion of Mg (II) 275.2 nm and the neutral of Mg (I) 285.2 nm emission lines detected from the laser-induced plasma. It was observed that the ratio changes with respect to the change in the tablet hardness, namely the ratio is higher for the hard tablet. Besides the ratio measurements, we also measured the depth profile of a tablet by focusing 60 shots of irradiation of laser light at a fixed position on the surface of the tablet. It was found that the depth profile varies differently with the hardness of the tablet. These experiment results show that the technique of LISPS can be applied to examine the quality of pharmaceutical products.

  2. Application of Best Estimate Approach for Modelling of QUENCH-03 and QUENCH-06 Experiments

    Directory of Open Access Journals (Sweden)

    Tadas Kaliatka

    2016-04-01

    In this article, the QUENCH-03 and QUENCH-06 experiments are modelled using ASTEC and RELAP/SCDAPSIM codes. For the uncertainty and sensitivity analysis, SUSA3.5 and SUNSET tools were used. The article demonstrates that applying the best estimate approach, it is possible to develop basic QUENCH input deck and to develop the two sets of input parameters, covering maximal and minimal ranges of uncertainties. These allow simulating different (but with the same nature tests, receiving calculation results with the evaluated range of uncertainties.

  3. Jet quenching and holographic thermalization with a chemical potential

    Energy Technology Data Exchange (ETDEWEB)

    Caceres, Elena [Facultad de Ciencias, Universidad de Colima,Bernal Diaz del Castillo 340, Colima (Mexico); Theory Group, Department of Physics,University of Texas at Austin, Austin, TX 78712 (United States); Kundu, Arnab [Theory Group, Department of Physics,University of Texas at Austin, Austin, TX 78712 (United States); Yang, Di-Lun [Department of Physics, Duke University,Durham, North Carolina 27708 (United States)

    2014-03-17

    We investigate jet quenching of virtual gluons and thermalization of a strongly-coupled plasma with a non-zero chemical potential via the gauge/gravity duality. By tracking a charged shell falling in an asymptotic AdS{sub d+1} background for d=3 and d=4, which is characterized by the AdS-Reissner-Nordström-Vaidya (AdS-RN-Vaidya) geometry, we extract a thermalization time of the medium with a non-zero chemical potential. In addition, we study the falling string as the holographic dual of a virtual gluon in the AdS-RN-Vaidya spacetime. The stopping distance of the massless particle representing the tip of the falling string in such a spacetime could reveal the jet quenching of an energetic light probe traversing the medium in the presence of a chemical potential. We find that the stopping distance decreases when the chemical potential is increased in both AdS-RN and AdS-RN-Vaidya spacetimes, which correspond to the thermalized and thermalizing media respectively. Moreover, we find that the soft gluon with an energy comparable to the thermalization temperature and chemical potential in the medium travels further in the non-equilibrium plasma. The thermalization time obtained here by tracking a falling charged shell does not exhibit, generically, the same qualitative features as the one obtained studying non-local observables. This indicates that — holographically — the definition of thermalization time is observer dependent and there is no unambiguos definition.

  4. Validation of Quench Simulation and Simulation of the TWIN Solenoid

    CERN Document Server

    Pots, Rosalinde Hendrika

    2015-01-01

    For the Future Circular Collider at CERN a multi-purpose detector is proposed. The 6T TWIN Solenoid, a very large magnet system with a stored energy of 53 GJ, is being designed. It is important to protect the magnet against quenches in the system. Therefore several existing quench protection systems are evaluated and simulations have be performed on quenches in the TWIN Solenoid. The simulations on quenches in the TWIN Solenoid have been performed with promising results; the hotspot temperatures do not exceed 120 K and layer to layer voltages stay below 500 V. Adding quench heaters to the system might improve the quench protection system further.

  5. Analysis of superconducting cavity quench events at SSRF

    Institute of Scientific and Technical Information of China (English)

    HOU Hong-Tao; LI Zheng; LIU Jian-Fei; ZHAO Yu-Bin; ZHAO Shen-jie; ZHANG Zhi-Gang; LUO Chen; FENG Zi-Qiang; MAO Dong-Qing; ZHENG Xiang

    2011-01-01

    Quench is important and dangerous to superconducting RF cavities. This paper illustrates the mechanism of quench and how a quench detector works, and analyzes the quench events happening during beam operations and cavity conditioning. We find that the quench protection is mostly triggered by some reasons such as fluctuation of cavity voltage, multipacting or arc, rather than a real cavity thermal breakdown. The results will be beneficial to optimize the operation parameters of superconducting cavities, to discover the real reasons for beam trip by quench interlock, and to improve the operation stability of superconducting RF systems.

  6. Quenched heavy-light decay constants

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, R.M.; Booth, S.P.; Bowler, K.C.; Collins, S.; Henty, D.S.; Kenway, R.D.; Richards, D.G.; Shanahan, H.P.; Simone, J.N.; Simpson, A.D.; Wilkes, B.E. (Department of Physics, The University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom)); Ewing, A.K.; Lellouch, L.; Sachrajda, C.T.; Wittig, H. (Physics Department, The University, Southampton SO9 5NH (United Kingdom)); (UKQCD Collaboration)

    1994-02-01

    We present results for heavy-light decay constants, using both propagating quarks and the static approximation, in [ital O]([ital a])-improved, quenched lattice QCD. At [beta]=6.2 on a 24[sup 3][times]48 lattice we find [ital f][sub [ital D

  7. Lattice QCD simulations beyond the quenched approximation

    Energy Technology Data Exchange (ETDEWEB)

    Ukawa, A. (European Organization for Nuclear Research, Geneva (Switzerland). Theory Div.)

    1989-07-01

    Present status of lattice QCD simulations incorporating the effects of dynamical quarks is presented. After a brief review of the formalism of lattice QCD, the dynamical fermion algorithms in use today are described. Recent attempts at the hadron mass calculation are discussed in relation to the quenched results, and current understanding on the finite temperature behavior of QCD is summarized. (orig.).

  8. An improved process for high nutrition of germinated brown rice production: Low-pressure plasma.

    Science.gov (United States)

    Chen, Hua Han; Chang, Hung Chia; Chen, Yu Kuo; Hung, Chien Lun; Lin, Su Yi; Chen, Yi Sheng

    2016-01-15

    Brown rice was exposed to low-pressure plasma ranging from 1 to 3kV for 10min. Treatment of brown rice in low-pressure plasma increases the germination percentage, seedling length, and water uptake in laboratory germination tests. Of the various treatments, 3-kV plasma exposure for 10min yielded the best results. In germinating brown rice, α-amylase activity was significantly higher in treated groups than in controls. The higher enzyme activity in plasma-treated brown rice likely triggers the rapid germination and earlier vigor of the seedlings. Low-pressure plasma also increased gamma-aminobutyric acid (GABA) levels from ∼19 to ∼28mg/100g. In addition, a marked increase in the antioxidant activity of brown rice was observed with plasma treatments compared to controls. The main finding of this study indicates that low-pressure plasma is effective at enhancing the growth and GABA accumulation of germinated brown rice, which can supply high nutrition to consumer.

  9. Plasma nitrate clearance in mice: modeling of the systemic production of nitrate following the induction of nitric oxide synthesis.

    Science.gov (United States)

    Veszelovsky, E; Holford, N H; Thomsen, L L; Knowles, R G; Baguley, B C

    1995-01-01

    Nitric oxide (NO) is produced in mammals by the enzyme NO synthase (NOS) in response to a number of agents, including the experimental antitumour agent flavone acetic acid (FAA) and the cytokine tumour necrosis factor-alpha (TNF). NO is converted rapidly in the presence of oxygen, water and haemoglobin to oxidation products, largely nitrate. To quantitate the production of nitric oxide it is necessary to know the clearance of nitrate. The concentration of nitrite and nitrate ion in the plasma of C3H and BDF1 (C57BL6 x DBA2) mice was assessed before and after injection of sodium nitrate and sodium nitrite. Nitrite was covered rapidly to nitrate and the kinetics of elimination of nitrate were determined. There was no significant difference between results obtained with different mouse strains, between levels of nitrite and nitrate, or between i.p. and i.v. administration, and the observations were therefore combined. The volume of distribution of nitrate was 0.71 +/- 0.04 l/kg and the clearance was 0.32 +/- 0.02 l/h-1/kg-1 (plasma half-life, 1.54 h). Using previously published data, we developed a pharmacokinetic-pharmacodynamic model that relates the production of TNF in response to administration of FAA, the enhancement of NOS activity in response to TNF, and the elevation of plasma nitrate in response to NO production. This information permits the prediction from observed plasma nitrate values of the amount of NOS induced in vivo.

  10. Hepatitis E virus and the safety of plasma products: investigations into the reduction capacity of manufacturing processes.

    Science.gov (United States)

    Farcet, Maria R; Lackner, Cornelia; Antoine, Gerhard; Rabel, Philip O; Wieser, Andreas; Flicker, Andreas; Unger, Ulrike; Modrof, Jens; Kreil, Thomas R

    2016-02-01

    Hepatitis E virus (HEV) has been transmitted by transfusion of labile blood products and the occasional detection of HEV RNA in plasma pools indicates that HEV viremic donations might enter the manufacturing process of plasma products. To verify the safety margins of plasma products with respect to HEV, virus reduction steps commonly used in their manufacturing processes were investigated for their effectiveness to reduce HEV. Detection methods for HEV removal (by reverse transcription quantitative polymerase chain reaction) and inactivation (using an infectivity assay) were established. Immunoaffinity chromatography and 20-nm virus filtration for Factor (F)VIII, cold ethanol fractionation, and low-pH treatment for immunoglobulin, heat treatment for human albumin, and 35-nm nanofiltration for FVIII inhibitor-bypassing activity (FEIBA) were investigated for their capacity to reduce HEV or the physicochemically similar viruses feline calicivirus (FCV) and hepatitis A virus (HAV). For FVIII, HEV reduction of 3.9 and more than 3.9 log was demonstrated for immunoaffinity chromatography and 20-nm nanofiltration, respectively, and the cold ethanol fractionation for immunoglobulin removed more than 3.5 log of HEV, to below the limit of detection (LOD). Heat treatment of human albumin inactivated more than 3.1 log of HEV to below the LOD and 35-nm nanofiltration removed 4.0 log of HEV from the FEIBA intermediate. The results indicated HAV rather than FCV as the more relevant model virus for HEV. Substantial HEV reduction during processes commonly used in the manufacturing of plasma products was demonstrated, similar to that previously demonstrated for HAV. © 2015 AABB.

  11. Cold atmospheric pressure plasma treatment of ready-to-eat meat: inactivation of Listeria innocua and changes in product quality.

    Science.gov (United States)

    Rød, Sara Katrine; Hansen, Flemming; Leipold, Frank; Knøchel, Susanne

    2012-05-01

    The application of cold atmospheric pressure plasma for decontamination of a sliced ready-to-eat (RTE) meat product (bresaola) inoculated with Listeria innocua was investigated. Inoculated samples were treated at 15.5, 31, and 62 W for 2-60 s inside sealed linear-low-density-polyethylene bags containing 30% oxygen and 70% argon. Treatments resulted in a reduction of L. innocua ranging from 0.8 ± 0.4 to 1.6 ± 0.5 log cfu/g with no significant effects of time and intensity while multiple treatments at 15.5 and 62 W of 20 s with a 10 min interval increased reduction of L. innocua with increasing number of treatments. Concentrations of thiobarbituric acid reactive substances (TBARS) increased with power, treatments and storage time and were significantly higher than those of control samples after 1 and 14 days of storage at 5 °C. However, the levels were low (from 0.1 to 0.4 mg/kg) and beneath the sensory threshold level. Surface colour changes included loss of redness of ∼40% and 70% after 1 and 14 days of storage, respectively, regardless of plasma treatment. The results indicate that plasma may be applicable in surface decontamination of pre-packed RTE food products. However, oxidation may constitute an issue in some products.

  12. Plasma phospholipid pentadecanoic acid, EPA, and DHA, and the frequency of dairy and fish product intake in young children

    Directory of Open Access Journals (Sweden)

    Nicolai A. Lund-Blix

    2016-08-01

    Full Text Available Background: There is a lack of studies comparing dietary assessment methods with the biomarkers of fatty acids in children. Objective: The objective was to evaluate the suitability of a food frequency questionnaire (FFQ to rank young children according to their intake of dairy and fish products by comparing food frequency estimates to the plasma phospholipid fatty acids pentadecanoic acid, eicosapentaenoic acid (EPA, and docosahexaenoic acid (DHA. Design: Cross-sectional data for the present study were derived from the prospective cohort ‘Environmental Triggers of Type 1 Diabetes Study’. Infants were recruited from the Norwegian general population during 2001–2007. One hundred and ten (age 3–10 years children had sufficient volumes of plasma and FFQ filled in within 2 months from blood sampling and were included in this evaluation study. The quantitative determination of plasma phospholipid fatty acids was done by fatty acid methyl ester analysis. The association between the frequency of dairy and fish product intake and the plasma phospholipid fatty acids was assessed by a Spearman correlation analysis and by investigating whether participants were classified into the same quartiles of distribution. Results: Significant correlations were found between pentadecanoic acid and the intake frequency of total dairy products (r=0.29, total fat dairy products (r=0.39, and cheese products (r=0.36. EPA and DHA were significantly correlated with the intake frequency of oily fish (r=0.26 and 0.37, respectively and cod liver/fish oil supplements (r=0.47 for EPA and r=0.50 DHA. To a large extent, the FFQ was able to classify individuals into the same quartile as the relevant fatty acid biomarker. Conclusions: The present study suggests that, when using the plasma phospholipid fatty acids pentadecanoic acid, EPA, and DHA as biomarkers, the FFQ used in young children showed a moderate capability to rank the intake frequency of dairy products with a

  13. Neutron Production Rates by Inverse-Beta Decay in Fully Ionized Plasmas

    CERN Document Server

    Maiani, L; Riquer, V

    2014-01-01

    Recently we showed that the nuclear transmutation rates are largely overestimated in the Widom-Larsen theory of the so called `Low Energy Nuclear Reactions'. Here we show that unbound plasma electrons are even less likely to initiate nuclear transmutations.

  14. Fibrin and fibrinogen degradation products in plasma : clinical and methodological studies using enzyme immuno assays

    NARCIS (Netherlands)

    H. Kroneman (Herman)

    1992-01-01

    textabstractThis thesis comprises studies with monoclonal antibody-based plasma assays for derivatives of fibrin and fibrinogen in patients with diseases and conditions characterized by an activated state of coagulation and fibrinolysis

  15. 提高丙烯腈回收率的一种新型急冷工艺和急冷塔%A new quenching process and tower to improve the recovery of acrylonitrile

    Institute of Scientific and Technical Information of China (English)

    甘永胜; 顾军民; 方永成

    2004-01-01

    Quenching process and design of the quenching tower in acrylonitrile production in China were studied in order to decrease the polymerization loss of acrylonitrile in the quenching tower.Based on the research of acrylonitrile polymerization in the quenching tower,a new quenching process was proposed to avoid the disadvantages of the original process.Two kinds of internals were installed to improve the performance of the quenching tower.Through a series of air-flow and real-flow model experiments,the new quenching process and new design were showed to be successful in enhancing the mass and heat transfer in the vapor-liquid system and decreasing the loss of acrylonitrile.Industrial application showed satisfactory results of decrease of the acrylonitrile loss in the quenching tower by about 4.5% and increase of the acrylonitrile recovery of the whole plant by more than 4%.

  16. Evaluation of Enoyl-Acyl Carrier Protein Reductase Inhibitors as Pseudomonas aeruginosa Quorum-Quenching Reagents

    Directory of Open Access Journals (Sweden)

    Søren Molin

    2010-02-01

    Full Text Available Pseudomonas aeruginosa is an opportunistic pathogen which is responsible for a wide range of infections. Production of virulence factors and biofilm formation by P. aeruginosa are partly regulated by cell-to-cell communication quorum-sensing systems. Identification of quorum-quenching reagents which block the quorum-sensing process can facilitate development of novel treatment strategies for P. aeruginosa infections. We have used molecular dynamics simulation and experimental studies to elucidate the efficiencies of two potential quorum-quenching reagents, triclosan and green tea epigallocatechin gallate (EGCG, which both function as inhibitors of the enoyl-acyl carrier protein (ACP reductase (ENR from the bacterial type II fatty acid synthesis pathway. Our studies suggest that EGCG has a higher binding affinity towards ENR of P. aeruginosa and is an efficient quorum-quenching reagent. EGCG treatment was further shown to be able to attenuate the production of virulence factors and biofilm formation of P. aeruginosa.

  17. System size dependence of nuclear modification and azimuthal anisotropy of jet quenching

    CERN Document Server

    De, Somnath

    2011-01-01

    We investigate the system size dependence of jet-quenching by analyzing transverse momentum spectra of neutral pions in Au+Au and Cu+Cu collisions at $\\sqrt{s_{\\textrm{NN}}}$ =200 GeV for different centralities. The fast partons are assumed to lose energy by radiating gluons as they traverse the plasma and undergo multiple collisions. The energy loss per collision, $\\epsilon$, is taken as proportional $E$ (where $E$ is the energy of the parton), proportional to $\\sqrt{E}$, or a constant depending on whether the formation time of the gluon is less than the mean path, greater than the mean free path but less than the path length, or greater than the path length of the partons, respectively. NLO pQCD is used to evaluate pion production by modifying the fragmentation function to account for the energy loss. We reproduce the nuclear modification factor $R_\\textrm{AA}$ by treating $\\epsilon$ as the only free parameter, depending on the centrality and the mechanism of energy loss. These values are seen to provide nu...

  18. SURFACE PREPARATION OF PRODUCTS MADE FROM Д16T ALLOYS PRIOR TO APPLICATION OF VACUUM-PLASMA COATINGS

    Directory of Open Access Journals (Sweden)

    S. Ivaschenko

    2013-01-01

    Full Text Available The paper presents results of  investigations on qualitative and quantitative characteristics of impurities on the surface of products made from aluminium alloy Д16Т .It has been shown that the main impurities of the products made from alloy Д16Т  are carbo-hydrates of paraffin and methanoic series.  In order to obtain high quality coating a technological process pertaining to surface cleaning prior to application vacuum-plasma coatings must include out- and intra-chamber treatments. 

  19. 基于模拟的热处理工艺设计:使淬火工艺与钢种和产品几何形状相匹配%Using Simulation for Heat Treatment Process Design:Matching Quenching Process with Steel Grade and Product Geometry

    Institute of Scientific and Technical Information of China (English)

    B.L.Ferguson; Z. Li

    2014-01-01

    The performance of steel parts is heavily dependent on the heat treatment process applied .The alloy content of the steel establishes the steel hardenability . The severity of the quenching establishes the local temperature history throughout the body of the part .In combination , the steel hardenability and the quenching process determine the final microstructure , mechanical properties , residual stress state and the performance of the part.The residual stress state , especially the surface stress state , is a significant factor in affecting fatigue life of the part.The steel hardenability and quenching practice can be adjusted to enhance residual surface compression and improve the fatigue life of a component .Computer simulation of the heat treatment process that includes calculation of the metallurgical phase transformations during the heating and cooling processes offers a method for scientifically designing the heat treatment process and selecting the steel alloy to optimise the performance of a particular product .In this paper , the DANTE heat treatment simulation software will be used to demonstrate this design methodology for a spur gear .%钢铁零件的性能主要决定于所采用的热处理工艺。钢的淬透性决定于合金元素含量,而淬火烈度确定了整个零件中不同部位的温度随时间变化过程。总的来说,零件最终的组织、力学性能、残余应力状态和服役性能均取决于钢的淬透性和淬火工艺。残余应力状态,特别是表面应力状态,是影响零件疲劳寿命的重要因素,可通过控制钢的淬透性和淬火工艺来提高零件的表面压应力,从而提高疲劳寿命。热处理工艺的计算机模拟,包括加热和冷却过程中的相变的计算,提供了一种科学地进行热处理工艺设计、钢种选择以优化某一特定产品性能的方法。本文采用热处理模拟软件DANTE来论证这种设计方法在正齿轮上的应用。

  20. Simulation of bundle test Quench-12 with integral code MELCOR

    Energy Technology Data Exchange (ETDEWEB)

    Duspiva, J. [Nuclear Research Inst., Rez plc (Czech Republic)

    2011-07-01

    The past NRI analyses cover the Quench-01, Quench-03 and Quench-06 with version MELCOR 1.8.5 (including reflood model), and Quench-01 and Quench-11 tests with the latest version MELCOR 1.8.6. The Quench-12 test is specific, because it has different bundle configuration related to the VVER bundle configuration with hexagonal grid of pins and also used E110 cladding material. Specificity of Quench-12 test is also in the used material of fuel rod cladding - E110. The test specificities are a reason for the highest concern, because the VVER reactors are operated in the Czech Republic. The new input model was developed with the taking into account all experience from previous simulations of the Quench bundle tests. The recent version MELCOR 1.8.6 YU{sub 2}911 was used for the simulation with slightly modified ELHEAT package. Sensitivity studies on input parameters and oxidation kinetics were performed. (author)

  1. Expanding plasmas from anti de Sitter black holes

    Energy Technology Data Exchange (ETDEWEB)

    Camilo, Giancarlo [Instituto de Fisica, Universidade de Sao Paulo, Departamento de Fisica Matematica, Sao Paulo (Brazil)

    2016-12-15

    We introduce a new foliation of AdS{sub 5} black holes such that the conformal boundary takes the form of a 4-dimensional FLRW spacetime with scale factor a(t). The foliation employs Eddington-Finkelstein-like coordinates and is applicable to a large class of AdS black holes, supported by matter fields or not, considerably extending previous efforts in the literature. We argue that the holographic dual picture of a CFT plasma on a FLRW background provides an interesting prototype to study the nonequilibrium dynamics of expanding plasmas and use holographic renormalization to extract the renormalized energy-momentum tensor of the dual plasma. We illustrate the procedure for three black holes of interest, namely AdS-Schwarzschild, AdS-Gauss-Bonnet, and AdS-Reissner-Nordstroem. For the latter, as a by-product, we show that the nonequilibrium dynamics of a CFT plasma subject to a quench in the chemical potential (i.e., a time-dependent chemical potential) resembles a cosmological evolution with the scale factor a(t) being inversely related to the quench profile μ(t). (orig.)

  2. Expanding plasmas from anti de Sitter black holes

    Science.gov (United States)

    Camilo, Giancarlo

    2016-12-01

    We introduce a new foliation of AdS_5 black holes such that the conformal boundary takes the form of a 4-dimensional FLRW spacetime with scale factor a( t). The foliation employs Eddington-Finkelstein-like coordinates and is applicable to a large class of AdS black holes, supported by matter fields or not, considerably extending previous efforts in the literature. We argue that the holographic dual picture of a CFT plasma on a FLRW background provides an interesting prototype to study the nonequilibrium dynamics of expanding plasmas and use holographic renormalization to extract the renormalized energy-momentum tensor of the dual plasma. We illustrate the procedure for three black holes of interest, namely AdS-Schwarzschild, AdS-Gauss-Bonnet, and AdS-Reissner-Nordström. For the latter, as a by-product, we show that the nonequilibrium dynamics of a CFT plasma subject to a quench in the chemical potential (i.e., a time-dependent chemical potential) resembles a cosmological evolution with the scale factor a( t) being inversely related to the quench profile μ (t).

  3. Ion firehose instability in a dusty plasma considering product-bi-kappa distributions for the plasma particles

    Energy Technology Data Exchange (ETDEWEB)

    Santos, M. S. dos, E-mail: michel.santos@iffarroupilha.edu.br [Instituto de Física, Universidade Federal do Rio Grande do Sul, 91501-970, Porto Alegre, RS (Brazil); Instituto Federal de Educação, Ciência e Tecnologia Farroupilha, 98590-000, Santo Augusto, RS (Brazil); Ziebell, L. F., E-mail: luiz.ziebell@ufrgs.br; Gaelzer, R., E-mail: rudi.gaelzer@ufrgs.br [Instituto de Física, Universidade Federal do Rio Grande do Sul, 91501-970, Porto Alegre, RS (Brazil)

    2016-01-15

    We study the dispersion relation for low frequency waves in the whistler mode propagating along the ambient magnetic field, considering ions and electrons with product-bi-kappa (PBK) velocity distributions and taking into account the presence of a population of dust particles. The results obtained by numerical analysis of the dispersion relation show that the decrease in the κ indexes in the ion PBK distribution contributes to the increase in magnitude of the growth rates of the ion firehose instability and the size of the region in wave number space where the instability occurs. It is also shown that the decrease in the κ indexes in the electron PBK distribution contribute to decrease in the growth rates of instability, despite the fact that the instability occurs due to the anisotropy in the ion distribution function. For most of the interval of κ values which has been investigated, the ability of the non-thermal ions to increase the instability overcomes the tendency of decrease due to the non-thermal electron distribution, but for very small values of the kappa indexes the deleterious effect of the non-thermal electrons tends to overcome the effect due to the non-thermal ion distribution.

  4. Single photon detection with self-quenching multiplication

    Science.gov (United States)

    Zheng, Xinyu (Inventor); Cunningham, Thomas J. (Inventor); Pain, Bedabrata (Inventor)

    2011-01-01

    A photoelectronic device and an avalanche self-quenching process for a photoelectronic device are described. The photoelectronic device comprises a nanoscale semiconductor multiplication region and a nanoscale doped semiconductor quenching structure including a depletion region and an undepletion region. The photoelectronic device can act as a single photon detector or a single carrier multiplier. The avalanche self-quenching process allows electrical field reduction in the multiplication region by movement of the multiplication carriers, thus quenching the avalanche.

  5. Suppression of adenylyl cyclase-mediated cAMP production by plasma membrane associated cytoskeletal protein 4.1G.

    Science.gov (United States)

    Goto, Toshihiro; Chiba, Ayano; Sukegawa, Jun; Yanagisawa, Teruyuki; Saito, Masaki; Nakahata, Norimichi

    2013-03-01

    It has been shown lately that activity of G protein-coupled receptors (GPCRs) is regulated by an array of proteins binding to carboxy (C)-terminus of GPCRs. Proteins of 4.1 family are subsets of subcortical cytoskeletal proteins and are known to stabilize cellular structures and proteins at the plasma membrane. One of the 4.1 family proteins, 4.1G has been shown to interact with the C-terminus of GPCRs and regulate intracellular distribution of the receptors, including parathyroid hormone (PTH)/PTH-related protein receptor (PTHR). PTHR is coupled to trimeric G proteins G(s) and G(q), which activate the adenylyl cyclase/cyclic AMP (cAMP) pathway and phospholipase C pathway, respectively. During the course of investigation of the role of 4.1G on adenylyl cyclase/cAMP signaling pathway, we found that 4.1G suppressed forskolin-induced cAMP production in cells. The cAMP accumulation induced by forskolin was decreased in HEK293 cells overexpressing 4.1G or increased in 4.1G-knockdown cells. Furthermore, PTH -(1-34)-stimulated cAMP production was also suppressed in the presence of exogenously expressed 4.1G despite its activity to increase the distribution of PTHR to the cell surface. In cells overexpressing FERM domain-deleted 4.1G, a mutant form of the protein deficient in plasma membrane distribution, neither forskolin-induced nor PTH -(1-34)-stimulated cAMP production was not altered. The suppression of the forskolin-induced cAMP production was observed even in membrane preparations of 4.1G-overexpressing cells. In 4.1G-knockdown HEK293 cells, plasma membrane distribution of adenylyl cyclase 6, one of the major subtypes of the enzyme in the cells, showed a slight decrease, in spite of the increased production of cAMP in those cells when stimulated by forskolin. Also, cytochalasin D treatment did not cause any influence on forskolin-induced cAMP production in HEK293 cells. These data indicate that plasma membrane-associated 4.1G regulates GPCR-mediated G(s) signaling

  6. Nanosecond pulsed humid Ar plasma jet in air: shielding, discharge characteristics and atomic hydrogen production

    Science.gov (United States)

    Yatom, Shurik; Luo, Yuchen; Xiong, Qing; Bruggeman, Peter J.

    2017-10-01

    Gas phase non-equilibrium plasmas jets containing water vapor are of growing interest for many applications. In this manuscript, we report a detailed study of an atmospheric pressure nanosecond pulsed Ar  +  0.26% H2O plasma jet. The plasma jet operates in an atmospheric pressure air surrounding but is shielded with a coaxial argon flow to limit the air diffusion into the jet effluent core. The jet impinges on a metal plate electrode and produces a stable plasma filament (transient spark) between the needle electrode in the jet and the metal plate. The stable plasma filament is characterized by spatially and time resolved electrical and optical diagnostics. This includes Rayleigh scattering, Stark broadening of the hydrogen Balmer lines and two-photon absorption laser induced fluorescence (TaLIF) to obtain the gas temperature, the electron density and the atomic hydrogen density respectively. Electron densities and atomic hydrogen densities up to 5 × 1022 m-3 and 2 × 1022 m-3 have been measured. This shows that atomic hydrogen is one of the main species in high density Ar-H2O plasmas. The gas temperature does not exceed 550 K in the core of the plasma. To enable in situ calibration of the H TaLIF at atmospheric pressure a previously published O density calibration scheme is extended to include a correction for the line profiles by including overlap integrals as required by H TaLIF. The line width of H TaLIF, due to collision broadening has the same trend as the neutral density obtained by Rayleigh scattering. This suggests the possibility to use this technique to in situ probe neutral gas densities.

  7. Static and dynamic quenching of luminescent species in polymer media.

    Science.gov (United States)

    Hartmann, P; Leiner, M J; Lippitsch, M E

    1994-12-01

    A method developed for quantitative determination of static and dynamic contributions to luminescence quenching is applied to Ru(II) complexes in polymer matrices (silica gel and polystyrene), quenched by oxygen. This method is based on both intensity and lifetime quenching experiments. The curvature of intensity Stern-Volmer plots is related to the results.

  8. First experience with the new coupling loss induced quench system

    NARCIS (Netherlands)

    Ravaioli, E.; Datskov, V.I.; Dudarev, A.V.; Kirby, G.; Sperin, K.A.; Kate, ten H.H.J.; Verweij, A.P.

    2014-01-01

    New-generation high-field superconducting magnets pose a challenge relating to the protection of the coil winding pack in the case of a quench. The high stored energy per unit volume calls for a very efficient quench detection and fast quench propagation in order to avoid damage due to overheating. A

  9. The coffee diterpene cafestol increases plasma triacylglycerol by increasing the production rate of large VLDL apolipoprotein B in healthy normolipidemic subjects

    NARCIS (Netherlands)

    Roos, de B.; Caslake, M.J.; Stalenhoef, A.F.H.; Bedford, D.; Demacker, P.N.; Katan, M.B.; Packard, C.J.

    2001-01-01

    Background: Cafestol is a diterpene in unfiltered coffee that raises plasma triacylglycerol in humans. Objective: We studied whether cafestol increases plasma triacylglycerol by increasing the production rate or by decreasing the fractional catabolic rate of VLDL1 [Svedberg flotation unit (Sf) 60-40

  10. Formation of carbon deposits from coal in an arc plasma

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B.; Tian, Y.; Zhang, Y.; Zhu, S.; Lu, Y.; Zhang, Y.; Xie, K. [Taiyuan University of Technology, Taiyuan (China)

    2007-07-01

    The issue of deposited carbon (DC) on a reactor wall during the production of acetylene by the coal/arc plasma process is a potential obstacle for the industrialization process. The formation mechanism of DC is very difficult to reveal because the high complexity of coal and the volatile matter. Combining with quenching technique, the methane, liquid petroleum gas and benzene were employed as the model materials to roughly act as the light gas, chain and aromatic subcomponents of volatile matter, and then the reasonable formation mechanism of DC was subtly speculated accordingly.

  11. Plasma concentrations of parabens in postmenopausal women and self-reported use of personal care products: the NOWAC postgenome study.

    Science.gov (United States)

    Sandanger, Torkjel M; Huber, Sandra; Moe, Morten K; Braathen, Tonje; Leknes, Henriette; Lund, Eiliv

    2011-01-01

    Parabens are used extensively in personal care products; however, their estrogenic properties have raised concern over risks to human health. High levels of total parabens, mainly as conjugates, have been reported in human plasma/serum, with limited data on native parabens. Our objective was to assess and link plasma concentrations of native common parabens to self-reported use of personal care products in women from the general population. The information was obtained from an extensive questionnaire on diet and lifestyle previously answered by the women in the NOWAC study. Plasma samples from 332 individuals were extracted and cleaned up by automated solid phase extraction and analyzed by ultra high performance liquid chromatography time-of-flight mass spectrometry. Native methyl paraben dominated and was detected in 63% of the samples, with a median level of 9.4 ng/ml. Ethyl paraben (median paraben (median parabens were not detected. For the first time, elevated levels of native parabens are reported in women from the general population. The concentrations were significantly associated with the use of skin lotions, indicating that frequent (daily or more) use maintain elevated concentrations despite the parabens short half-lives. These findings clearly emphasize the need to study potential health effects in the general population.

  12. Collapse and Revival in Holographic Quenches

    CERN Document Server

    da Silva, Emilia; Mas, Javier; Serantes, Alexandre

    2014-01-01

    We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.

  13. Quench from Mott Insulator to Superfluid

    Energy Technology Data Exchange (ETDEWEB)

    Zurek, Wojciech H. [Los Alamos National Laboratory; Dziarmaga, Jacek [Instytut Fizyki Uniwersytetu Jagiello´nskiego; Tylutki, Marek [Instytut Fizyki Uniwersytetu Jagiello´nskiego

    2012-06-01

    We study a linear ramp of the nearest-neighbor tunneling rate in the Bose-Hubbard model driving the system from the Mott insulator state into the superfluid phase. We employ the truncated Wigner approximation to simulate linear quenches of a uniform system in 1...3 dimensions, and in a harmonic trap in 3 dimensions. In all these setups the excitation energy decays like one over third root of the quench time. The -1/3 scaling is explained by an impulse-adiabatic approximation - a variant of the Kibble-Zurek mechanism - describing a crossover from non-adiabatic to adiabatic evolution when the system begins to keep pace with the increasing tunneling rate.

  14. Quench dynamics in silver coated YBCO tapes

    Science.gov (United States)

    Duckworth, R. C.; Pfotenhauer, J. M.; Lue, J. W.; Gouge, M. J.; Lee, D. F.; Kroeger, D. M.

    2002-05-01

    The role of silver in the quench dynamics of RABiTS-processed YBCO tapes was examined. The voltage distribution along the 20 cm long YBCO tapes with silver thickness between two and eight micrometers was measured when different transport current pulses were applied. Measurements on each sample were performed in a conduction-cooling environment at approximately 50 K. After normal regions were induced in the sample by short over-current pulses, an operating current was applied to monitor the sample recovery or quench. When scaled to the lowest critical current, a thermal runaway current was identified and found to increase with increasing silver thickness. A simple one-dimensional model of the system supported this trend. [This paper is also published in Advances in Cryogenic Engineering Volume 47A, AIP Conference Proceedings Volume 613, pp. 449-456.

  15. Quench dynamics of the anisotropic Heisenberg model.

    Science.gov (United States)

    Liu, Wenshuo; Andrei, Natan

    2014-06-27

    We develop an analytical approach for the study of the quench dynamics of the anisotropic Heisenberg model (XXZ model) on the infinite line. We present the exact time-dependent wave functions after a quench in an integral form for any initial state and for any anisotropy Δ by means of a generalized Yudson contour representation. We calculate the evolution of several observables from two particular initial states: starting from a local Néel state we calculate the time evolution of the antiferromagnetic order parameter-staggered magnetization; starting from a state with consecutive flipped spins (1) we calculate the evolution of the local magnetization and express it in terms of the propagation of magnons and bound state excitations, and (2) we predict the evolution of the induced spin currents. These predictions can be confronted with experiments in ultracold gases in optical lattices. We also show how the "string" solutions of Bethe ansatz equations emerge naturally from the contour approach.

  16. Collapse and revival in holographic quenches

    Science.gov (United States)

    da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre

    2015-04-01

    We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.

  17. Plasma-photocatalyst interaction: Production of oxygen atoms in a low pressure discharge

    Science.gov (United States)

    Guaitella, O.; Gatilova, L.; Rousseau, A.

    2005-04-01

    A pulsed dc low pressure discharge in air (210 Pa) is used to study the mechanisms of activation of a photocatalytic material (TiO2) under plasma exposure. It is first shown that the presence of TiO2 inside the plasma region leads to a strong increase of the reduced electric field. Time resolved measurement of the atomic oxygen density is performed by actinometry during a 10 ms pulse at a low repetition rate (1 Hz) with and without TiO2 pellets inside the plasma region. The presence of TiO2 pellets strongly increases the O atom density during the first millisecond, but this effect saturates for longer exposure times.

  18. Microwave beatwave excitation of electron plasma wave and high energy electron production

    Energy Technology Data Exchange (ETDEWEB)

    Yatsuzuka, M.; Obata, K.; Nobuhara, S. [Himeji Inst. of Tech., Hyogo (Japan)

    1997-12-31

    Two X-band microwave beams with a slightly different frequency and the maximum output power of 50 kW are injected into a target plasma antiparallel to each other through a standard horn. The resonant excitation of an electron plasma wave is observed when the difference in frequency between counterstreaming microwaves is equal to the electron plasma frequency. The excited wave propagates in the same direction as the higher-frequency microwave with a wave length which satisfies the resonance condition of wave number. The wave amplitude grows with an increase in incident microwave power, and reaches the density perturbation {delta}n/n{sub 0} of approximately 3.2 % at the incident microwave power of 40 kW and beat frequency of 600 MHz. A small amount of high-energy electrons with the speed of 27 eV are observed in the high-power region of incident microwave. (author)

  19. Erosion products of plasma facing materials formed under ITER-like transient load and deuterium retention in them

    Energy Technology Data Exchange (ETDEWEB)

    Putrik, A. B., E-mail: putrik@triniti.ru; Klimov, N. S. [State Research Center of the Russian Federation Troitsk Institute for Innovation & Fusion Research (Russian Federation); Gasparyan, Yu. M., E-mail: yura@plasma.mephi.ru; Efimov, V. S. [National Research Nuclear University Moscow Engineering Physics Institute (Russian Federation); Barsuk, V. A.; Podkovyrov, V. L., E-mail: podk@triniti.ru; Zhitlukhin, A. M., E-mail: zhitlukh@triniti.ru; Yarochevskaya, A. D.; Kovalenko, D. V., E-mail: kovalenko@triniti.ru [State Research Center of the Russian Federation Troitsk Institute for Innovation & Fusion Research (Russian Federation)

    2015-12-15

    Erosion of the plasma-facing materials in particular evaporation of the materials in a fusion reactor under intense transient events is one of the problems of the ITER. The current experimental data are insufficient to predict the properties of the erosion products, a significant part of which will be formed during transient events (edge-localized modes (ELMs) and disruptions). The paper concerns the experimental investigation of the graphite and tungsten erosion products deposited under pulsed plasma load at the QSPA-T: heat load on the target was 2.6 MJ/m{sup 2} with 0.5 ms pulse duration. The designed diagnostics for measuring the deposition rate made it possible to determine that the deposition of eroded material occurs during discharge, and the deposition rate is in the range (0.1–100) × 10{sup 19} at/(cm{sup 2} s), which is much higher than that for stationary processes. It is found that the relative atomic concentrations D/C and D/(W + C) in the erosion products deposited during the pulse process are on the same level as for the stationary processes. An exposure of erosion products to photonic energy densities typical of those expected at mitigated disruptions in the ITER (pulse duration of 0.5–1 ms, integral energy density of radiation of 0.1–0.5 MJ/m2) significantly decreases the concentration of trapped deuterium.

  20. Many flaked particles generated by electric field stress working as an impulsive force in mass-production plasma etching equipment

    Science.gov (United States)

    Kasashima, Yuji; Uesugi, Fumihiko

    2015-09-01

    Particles generated in plasma etching significantly lower production yield. In plasma etching, etching reaction products adhere to the inner chamber walls, gradually forming films, and particles are generated by flaking of the deposited films due to electric field stress that acts boundary between the inner wall and the film. In this study, we have investigated the mechanism of instantaneous generation of many flaked particles using the mass-production reactive ion etching equipment. Particles, which flake off from the films on the ground electrode, are detected by the in-situ particle monitoring system using a sheet-shaped laser beam. The results indicate that the deposited films are severely damaged and flake off as numerous particles when the floating potential at the inner wall suddenly changes. This is because the rapid change in floating potential, observed when unusual wafer movement and micro-arc discharge occur, causes electric field stress working as an impulsive force. The films are easily detached by the impulsive force and many flaked particles are instantaneously generated. This mechanism can occur on not only a ground electrode but a chamber walls, and cause serious contamination in mass-production line. This work was partially supported by JSPS KAKENHI Grant Number B 26870903.

  1. Reductive fluorescence quenching of DMP with aniline

    Energy Technology Data Exchange (ETDEWEB)

    Asha Jhonsi, M. [B.S. Abdur Rahman University, Vandalur, Chennai 600048, Tamil Nadu (India); Kathiravan, A., E-mail: akathir23@hotmail.com [National Centre for Ultrafast Processes, University of Madras, Taramani Campus, Chennai 600113, Tamil Nadu (India)

    2014-01-15

    The photoinduced electron transfer (PET) between 8-(4-methoxyphenyl)-3,5-di[(E)-1-(4-methoxyphenyl)methylidene]-1,2,3,5,6, 7-hexahydrodicyclopenta[b,e]pyridine (DMP) and aniline is studied in acetonitrile medium by using steady state and time resolved absorption and fluorescence spectroscopic methods. Bimolecular quenching rate constants (k{sub q}) were calculated from the obtained linear Stern–Volmer plots from both steady state and time resolved measurements. The rate constant (k{sub q}) for PET between DMP and aniline is 1.4×10{sup 10} M{sup −1} s{sup −1}, which is in diffusion control limit. The free energy change (ΔG{sup 0}) has been evaluated by using Rehm–Weller equation for the evidence of electron transfer from aniline to DMP. Direct evidence for the electron transfer reaction in the present system has been obtained by characterizing the aniline cation radical using nanosecond time resolved absorption measurements in the visible region. Further, this quenching mechanism is attributed to be reductive in nature i.e. electron transfer occurs from ground state aniline to excited DMP. This is the first example of reductive fluorescence quenching of DMP with aniline in acetonitrile ever known. -- Highlights: • Photoinduced electron transfer between DMP and aniline using time resolved absorption and fluorescence spectroscopy has been investigated. • Reductive quenching behavior was observed. • Direct evidence for the ET reaction in the present system has been obtained by characterizing the aniline cation radical.

  2. Quenching of the Deuteron in Flight

    CERN Document Server

    Dillig, M

    2006-01-01

    We investigate the Lorentz contraction of a deuteron in flight. Our starting point is the Blankenbecler-Sugar projection of the Bethe-Salpeter equation to a 3-dimensional quasi potential equation, wqhich we apply for the deuteron bound in an harmonic oscillator potential (for an analytical result) and by the Bonn NN potential for a more realistic estimate. We find substantial quenching with increasing external momenta and a significant modification of the high momentum spectrum of the deuteron.

  3. Additional Beta due to Fast Fusion Products in D-3He Fusion Plasma

    Institute of Scientific and Technical Information of China (English)

    DENG Bai-Quan(邓柏权); G.A.Emmert; PENG Li-Lin(彭利林)

    2003-01-01

    An analytical formula for the additional beta due to fast fusion-born ions is derived by using the slowing-down approximation from the Fokker-Planck equation under the assumption of negligible loss term. It is found that the fast ion beta in a D-3 He fusion plasma at a typical temperature of 55 ke V is about 20% of the thermal beta,which is the same ratio as that obtained in a D-T plasma at 20keV.

  4. Production of fullerene ions by combining of plasma sputtering with laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, K., E-mail: yamada.keisuke@jaea.go.jp; Saitoh, Y.; Yokota, W. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2014-02-15

    We have produced C{sub 60} ion beams by combining plasma sputtering and laser ablation. A C{sub 60} sample was placed in an electron cyclotron resonance type ion source, negatively biased and sputtered by argon plasma. The beam current of C{sub 60}{sup +} decreased rapidly, but it was transiently recovered by a single laser shot that ablates the thin sample surface on the sputtered area. Temporal variations in beam current are reported in response to laser shots repeated at intervals of a few minutes.

  5. Production of CW High-Density Non-Equilibrium Plasma in the Atmosphere Using Microgap Discharge Excited by Microwave

    Science.gov (United States)

    Kono, Akihiro; Sugiyama, Tomohiko; Goto, Toshio; Furuhashi, Hideo; Uchida, Yoshiyuki

    2001-03-01

    A new technique for cw production of high-pressure, high-density, non-equilibrium plasma is presented. Using microwave excitation at 2.45 GHz, a stable atmospheric glow discharge was sustained between two knife-edge electrodes, having a length of 10 mm and facing each other across a ˜100 μm microgap. Laser Thomson scattering diagnostics indicates that the plasma density in the microgap is as high as 1.6× 1015 cm-3 at a microwave power of 100 W. The optical emission of the N2 second positive band indicates that the gas temperature in the microgap is 1800 K, much lower than the electron temperature.

  6. Successful magnet quench test for CAST.

    CERN Multimedia

    Brice Maximilien

    2002-01-01

    The CERN Axion Solar Telescope (CAST) consists of a prototype LHC dipole magnet with photon detectors at each end. It searches for very weakly interacting neutral particles called axions, which should originate in the core of the Sun. The telescope, located at Point 8, can move vertically within its wheeled platform, which travels horizontally along tracks in the floor. In this way, the telescope can view the Sun at sunrise through one end and at sunset through the other end. It has been cooled down to below 1.8 K and reached ~95% of its final magnetic field of 9 tesla before a quench was induced to test the whole cryogenic system under such conditions. The cryogenic system responded as expected to the magnet quench and CAST is now ready to start its three-year search for solar axions. Photos 01 & 02 : Members of the LHC cryogenics team pose in front of the axion telescope on the day of the first quench test, together with some of the CAST collaboration.

  7. Central and peripheral blood pressures in relation to plasma advanced glycation end products in a Chinese population.

    Science.gov (United States)

    Huang, Q-F; Sheng, C-S; Kang, Y-Y; Zhang, L; Wang, S; Li, F-K; Cheng, Y-B; Guo, Q-H; Li, Y; Wang, J-G

    2016-07-01

    We investigated the association of plasma AGE (advanced glycation end product) concentration with central and peripheral blood pressures and central-to-brachial blood pressure amplification in a Chinese population. The study subjects were from a newly established residential area in the suburb of Shanghai. Using the SphygmoCor system, we recorded radial arterial waveforms and derived aortic waveforms by a generalized transfer function and central systolic and pulse pressure by calibration for brachial blood pressure measured with an oscillometric device. The central-to-brachial pressure amplification was expressed as the central-to-brachial systolic blood pressure difference and pulse pressure difference and ratio. Plasma AGE concentration was measured by the enzyme-linked immunosorbent assay method and logarithmically transformed for statistical analysis. The 1051 participants (age, 55.1±13.1 years) included 663 women. After adjustment for sex, age and other confounding factors, plasma AGE concentration was associated with central but not peripheral blood pressures and with some of the pressure amplification indexes. Indeed, each 10-fold increase in plasma AGE concentration was associated with 2.94 mm Hg (P=0.04) higher central systolic blood pressure and 2.39% lower central-to-brachial pulse pressure ratio (P=0.03). In further subgroup analyses, the association was more prominent in the presence of hypercholesterolemia (+8.11 mm Hg, P=0.008) for central systolic blood pressure and in the presence of overweight and obesity (-4.89%, P=0.009), diabetes and prediabetes (-6.26%, P=0.10) or current smoking (-6.68%, P=0.045) for central-to-brachial pulse pressure ratio. In conclusion, plasma AGE concentration is independently associated with central systolic blood pressure and pulse pressure amplification, especially in the presence of several modifiable cardiovascular risk factors.

  8. The Mass Dependence of Dwarf Satellite Galaxy Quenching

    Science.gov (United States)

    Slater, Colin T.; Bell, Eric F.

    2014-09-01

    We combine observations of the Local Group with data from the NASA-Sloan Atlas to show the variation in the quenched fraction of satellite galaxies from low-mass dwarf spheroidals and dwarf irregulars to more massive dwarfs similar to the Magellanic Clouds. While almost all of the low-mass (M sstarf 5 Gyr ago. We also characterize how the susceptibility of dwarfs to ram pressure must vary as a function of mass if it is to account for the change in quenched fractions. Though neither model predicts the quenching effectiveness a priori, this modeling illustrates the physical requirements that the observed quenched fractions place on possible quenching mechanisms.

  9. Neutron production rates by inverse-beta decay in fully ionized plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Maiani, L.; Polosa, A.D.; Riquer, V. [Sapienza Universita di Roma, Dipartimento di Fisica (Italy); INFN, Rome (Italy)

    2014-04-15

    Recently we showed that the nuclear transmutation rates are largely overestimated in the Widom-Larsen theory of the so-called 'Low Energy Nuclear Reactions'. Here we show that unbound plasma electrons are even less likely to initiate nuclear transmutations. (orig.)

  10. Factors regulating immunoglobulin production by normal and disease-associated plasma cells.

    Science.gov (United States)

    Jackson, David A; Elsawa, Sherine F

    2015-01-21

    Immunoglobulins are molecules produced by activated B cells and plasma cells in response to exposure to antigens. Upon antigen exposure, these molecules are secreted allowing the immune system to recognize and effectively respond to a myriad of pathogens. Immunoglobulin or antibody secreting cells are the mature form of B lymphocytes, which during their development undergo gene rearrangements and selection in the bone marrow ultimately leading to the generation of B cells, each expressing a single antigen-specific receptor/immunoglobulin molecule. Each individual immunoglobulin molecule has an affinity for a unique motif, or epitope, found on a given antigen. When presented with an antigen, activated B cells differentiate into either plasma cells (which secrete large amounts of antibody that is specific for the inducing antigen), or memory B cells (which are long-lived and elicit a stronger and faster response if the host is re-exposed to the same antigen). The secreted form of immunoglobulin, when bound to an antigen, serves as an effector molecule that directs other cells of the immune system to facilitate the neutralization of soluble antigen or the eradication of the antigen-expressing pathogen. This review will focus on the regulation of secreted immunoglobulin by long-lived normal or disease-associated plasma. Specifically, the focus will be on signaling and transcriptional events that regulate the development and homeostasis of long-lived immunoglobulin secreting plasma cells.

  11. Efficient Plasma Production in Low Background Neutral Pressures with the M2P2 Prototype

    Science.gov (United States)

    Ziemba, T.; Euripides, P.; Winglee, R.; Slough, J.; Giersch, L.

    2003-01-01

    Mini-Magnetospheric Plasma Propulsion (M2P2) seeks the creation of a large-scale (10 km radius) magnetic wall or bubble (i.e. a magnetosphere) by the electromagnetic inflation of a small-scale (20 cm radius) dipole magnet. The inflated magnetosphere will intercept the solar wind and thereby provide high-speed propulsion with modest power and fuel requirements due to the gain provided by the ambient medium. Magnetic field inflation is produced by the injection of plasma onto the dipole magnetic field eliminating the need for large mechanical structures and added material weight at launch. For successful inflation of the magnetic bubble a beta near unity must be achieved along the imposed dipole field. This is dependent on the plasma parameters that can be achieved with a plasma source that provide continuous operation at the desired power levels of 1 to 2 kilowatts. Over the last two years we have been developing a laboratory prototype to demonstrate the inflation of the magnetic field under space-like conditions. In this paper we will present some of the latest results from the prototype development at the University of Washington and show that the prototype can produce high ionization efficiencies while operating in near space like neutral background pressures producing electron temperatures of a few tens of electron volts. This allows for operation with propellant expenditures lower than originally estimated.

  12. Production of high-beta magnetised plasmas by colliding supersonic flows from inverse wire arrays

    Science.gov (United States)

    Hare, Jack; Suttle, Lee; Lebedev, Sergey; Bennett, Matthew; Burdiak, Guy; Clayson, Thomas; Suzuki-Vidal, Francisco; Swadling, George; Patankar, Siddharth; Robinson, Timothy; Stuart, Nicholas; Smith, Roland; Yang, Qingguo; Wu, Jian; Rozmus, Wojciech

    2015-11-01

    HEDP often exhibit a high plasma β and an electron Hall parameter greater than one. This results in a complex interplay between the transport of heat and magnetic fields, relevant to the Magnetised Liner Inertial Fusion (MagLIF) concept. We can produce such plasmas by colliding two supersonic quasi-planar flows from two adjacent inverse wire arrays made from carbon. The standing shock formed by the collision heats and compresses the plasma. The plasma flows advect magnetic fields which are perpendicular to the flow direction. Depending on the experimental set up, this can result in either flux compression or reconnection in the interaction region. The experiments are conducted on MAGPIE (1.4 MA, 250 ns current pulse). The formed shock is stable over long timescales (~100 ns), and the electron temperature (100 eV) is close to the ion temperature (500 eV), measured by spatially resolved Thomson scattering. Magnetic fields above 5 T is observed using a Faraday rotation diagnostic, and an electron density of around 5x1017 cm-3 is measured by interferometry.

  13. Plasma membrane ubiquinone controls ceramide production and prevents cell death induced by serum withdrawal.

    Science.gov (United States)

    Barroso, M P; Gómez-Díaz, C; Villalba, J M; Burón, M I; López-Lluch, G; Navas, P

    1997-06-01

    Serum provides cultured cells with survival factors required to maintain growth. Its withdrawal induces the development of programmed cell death. HL-60 cells were sensitive to serum removal, and an increase of lipid peroxidation and apoptosis was observed. Long-term treatment with ethidium bromide induced the mitochondria-deficient rho(o)HL-60 cell line. These cells were surprisingly more resistant to serum removal, displaying fewer apoptotic cells and lower lipid peroxidation. HL-60 cells contained less ubiquinone at the plasma membrane than rho(o)HL-60 cells. Both cell types increased plasma membrane ubiquinone in response to serum removal, although this increase was much higher in rho(o) cells. Addition of ubiquinone to both cell cultures in the absence of serum improved cell survival with decreasing lipid peroxidation and apoptosis. Ceramide was accumulated after serum removal in HL-60 but not in rho(o)HL-60 cells, and exogenous ubiquinone reduced this accumulation. These results demonstrate a relationship between ubiquinone levels in the plasma membrane and the induction of serum withdrawal-induced apoptosis, and ceramide accumulation. Thus, ubiquinone, which is a central component of the plasma membrane electron transport system, can represent a first level of protection against oxidative damage caused by serum withdrawal.

  14. Multifluid MHD Investigation of Plasma Production and Transport in Saturn's Magnetosphere

    Science.gov (United States)

    Rajendar, A.; Paty, C. S.; Arridge, C. S.

    2014-12-01

    The dynamics of Saturn's inner magnetosphere are driven by the planet's strong magnetic field, rapid rotation rate, and interactions between magnetospheric plasma and Saturn's distributed neutral cloud. This cloud is composed mostly of water and OH molecules and primarily originates from the cryovolcanic plumes of Enceladus. Charge-exchange collisions between ions and neutrals result in a loss of momentum from the plasma, while photoionization and electron-impact ionization of neutrals produces new, slow-moving water group ions that are accelerated in the corotation direction by the J×Bforce associated with magnetosphere-ionosphere coupling currents. Unbalanced centrifugal stresses cause this newly-produced plasma to move radially outward, eventually leaving the magnetosphere. The characteristic signature of this process is the development of inward-moving fingers of hot, rarefied, outer magnetosphere plasma, as required by the conservation of magnetic flux. We investigate the dynamics of Saturn's inner magnetosphere using the latest iteration of the Saturn multifluid model with refined plasma-neutral interaction physics. Earlier versions of this model were used to investigate the external triggering of plasmoids and the interchange process using a fixed internal source rate. We use a static representation of Saturn's neutral cloud and modified multifluid MHD equations incorporating mass- and momentum-loading terms. Our collision physics calculations have been updated to include energy-dependent rate coefficients, and includes the ability to specify a radially-dependent suprathermal electron distribution to investigate ionization by this component. We validate our results using data from the Cassini Plasma Spectrometer and Magnetometer instruments (CAPS and MAG) during Saturn solstice. Inclusion of self-consistent ion-neutral interactions in our simulation allows us to examine the spatial and temporal variation in mass- and momentum-loading in the inner

  15. Exact solution for the quench dynamics of a nested integrable system

    Science.gov (United States)

    Mestyán, Márton; Bertini, Bruno; Piroli, Lorenzo; Calabrese, Pasquale

    2017-08-01

    Integrable models provide an exact description for a wide variety of physical phenomena. For example nested integrable systems contain different species of interacting particles with a rich phenomenology in their collective behavior, which is the origin of the unconventional phenomenon of spin-charge separation. So far, however, most of the theoretical work in the study of non-equilibrium dynamics of integrable systems has focussed on models with an elementary (i.e. not nested) Bethe ansatz. In this work we explicitly investigate quantum quenches in nested integrable systems, by generalizing the application of the quench action approach. Specifically, we consider the spin-1 Lai-Sutherland model, described, in the thermodynamic limit, by the theory of two different species of Bethe-ansatz particles, each one forming an infinite number of bound states. We focus on the situation where the quench dynamics starts from a simple matrix product state for which the overlaps with the eigenstates of the Hamiltonian are known. We fully characterize the post-quench steady state and perform several consistency checks for the validity of our results. Finally, we provide predictions for the propagation of entanglement and mutual information after the quench, which can be used as signature of the quasi-particle content of the model.

  16. Application of best estimate approach for modelling of QUENCH-03 and QUENCH-06 experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kaliatka, Tadas; Kaliatka, Algirdas; Vileiniskis, Virginijus [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, Breslaujos (Lithuania)

    2016-04-15

    One of the important severe accident management measures in the Light Water Reactors is water injection to the reactor core. The related phenomena are investigated by performing experiments and computer simulations. One of the most widely known is the QUENCH test-program. A number of analyses on QUENCH tests have also been performed by different computer codes for code validation and improvements. Unfortunately, any deterministic computer simulation is not free from the uncertainties. To receive the realistic calculation results, the best estimate computer codes should be used for the calculation with combination of uncertainty and sensitivity analysis of calculation results. In this article, the QUENCH-03 and QUENCH-06 experiments are modelled using ASTEC and RELAP/SCDAPSIM codes. For the uncertainty and sensitivity analysis, SUSA3.5 and SUNSET tools were used. The article demonstrates that applying the best estimate approach, it is possible to develop basic QUENCH input deck and to develop the two sets of input parameters, covering maximal and minimal ranges of uncertainties. These allow simulating different (but with the same nature) tests, receiving calculation results with the evaluated range of uncertainties.

  17. Effects of the pulse width on the reactive species production and DNA damage in cancer cells exposed to atmospheric pressure microsecond-pulsed helium plasma jets

    Science.gov (United States)

    Joh, Hea Min; Choi, Ji Ye; Kim, Sun Ja; Kang, Tae Hong; Chung, T. H.

    2017-08-01

    Plasma-liquid and plasma-cell interactions were investigated using an atmospheric pressure dc microsecond-pulsed helium plasma jet. We investigated the effects of the electrical parameters such as applied voltage and pulse width (determined by the pulse frequency and duty ratio) on the production of reactive species in the gas/liquid phases and on the DNA damage responses in the cancer cells. The densities of reactive species including OH radicals were estimated inside the plasma-treated liquids using a chemical probe method, and the nitrite concentration was detected by Griess assay. Importantly, the more concentration of OH resulted in the more DNA base oxidation and breaks in human lung cancer A549 cells. The data are very suggestive that there is strong correlation between the production of OH in the plasmas/liquids and the DNA damage.

  18. Development of Industrially Produced Composite Quench Heaters for the LHC Superconducting Lattice Magnets

    CERN Document Server

    Szeless, Balázs; Calvone, F

    1996-01-01

    The quench heaters are vital elements for the protection of the LHC superconducting lattice magnets in the case of resistive transitions of the conductor. The basic concept of magnet protection and technical solutions are briefly presented. The quench heater consists of partially copper clad stainless steel strips sandwiched in between electric insulating carrier foils with electrical and mechanical properties such as to withstand high voltages, low temperatures, pressures and ionizing radiation. Testing of some commercial available electric insulation foils, polyimide (PI), polyetheretherketon (PEEK) and polyarylate (PA) and combinations of adhesive systems which are suitable for industrial processing are described. Possible industrial methods for series production for some 80 km of these composite quench heaters are indicated.

  19. Tensor renormalization group: Local magnetizations, correlation functions, and phase diagrams of systems with quenched randomness

    Science.gov (United States)

    Güven, Can; Hinczewski, Michael; Berker, A. Nihat

    2011-03-01

    The tensor renormalization-group method, developed by Levin and Nave, brings systematic improvability to the position-space renormalization-group method and yields essentially exact results for phase diagrams and entire thermodynamic functions. The method, previously used on systems with no quenched randomness, is extended in this study to systems with quenched randomness. Local magnetizations and correlation functions as a function of spin separation are calculated as tensor products subject to renormalization-group transformation. Phase diagrams are extracted from the long-distance behavior of the correlation functions. The approach is illustrated with the quenched bond-diluted Ising model on the triangular lattice. An accurate phase diagram is obtained in temperature and bond-dilution probability for the entire temperature range down to the percolation threshold at zero temperature. This research was supported by the Alexander von Humboldt Foundation, the Scientific and Technological Research Council of Turkey (TÜBITAK), and the Academy of Sciences of Turkey.

  20. Tensor renormalization group: local magnetizations, correlation functions, and phase diagrams of systems with quenched randomness.

    Science.gov (United States)

    Güven, Can; Hinczewski, Michael; Berker, A Nihat

    2010-11-01

    The tensor renormalization-group method, developed by Levin and Nave, brings systematic improvability to the position-space renormalization-group method and yields essentially exact results for phase diagrams and entire thermodynamic functions. The method, previously used on systems with no quenched randomness, is extended in this study to systems with quenched randomness. Local magnetizations and correlation functions as a function of spin separation are calculated as tensor products subject to renormalization-group transformation. Phase diagrams are extracted from the long-distance behavior of the correlation functions. The approach is illustrated with the quenched bond-diluted Ising model on the triangular lattice. An accurate phase diagram is obtained in temperature and bond-dilution probability for the entire temperature range down to the percolation threshold at zero temperature.

  1. Quench propagation and protection analysis of the ATLAS Toroids

    CERN Document Server

    Dudarev, A; ten Kate, H H J; Baynham, D Elwyn; Courthold, M J D; Lesmond, C

    2000-01-01

    The ATLAS superconducting magnet system consists of the Barrel Toroid, two End Cap Toroids and the Central Solenoid. However, the Toroids of eight coils each are magnetically separate systems to the Central Solenoid. The Toroids are electrically connected in series and energized by a single power supply. The quench protection system is based on the use of relatively small external dump resistances in combination with quench-heaters activated after a quench event detection to initiate the internal dump of stored energy in all the coils. A rather strong quench-back effect due to eddy-currents in the coil casings at the transport current decay is beneficial for the quench protection efficiency in the event of heater failures. The quench behaviour of the ATLAS Toroids was computer simulated for normal operation of the quench protection system and its complete non-operation (failure) mode. (3 refs).

  2. Neonatal Plasma Polarizes TLR4-Mediated Cytokine Responses towards Low IL-12p70 and High IL-10 Production via Distinct Factors

    Science.gov (United States)

    Belderbos, Mirjam E.; Levy, Ofer; Stalpers, Femke; Kimpen, Jan L.; Meyaard, Linde; Bont, Louis

    2012-01-01

    Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR) responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs) produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP) or soluble CD14 (sCD14). The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection. PMID:22442690

  3. Neonatal plasma polarizes TLR4-mediated cytokine responses towards low IL-12p70 and high IL-10 production via distinct factors.

    Directory of Open Access Journals (Sweden)

    Mirjam E Belderbos

    Full Text Available Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP or soluble CD14 (sCD14. The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection.

  4. Minimum Quench Energy and Early Quench Development in NbTi Superconducting Strands

    CERN Document Server

    Breschi, M; Boselli, M; Bottura, Luca; Devred, Arnaud; Ribani, P L; Trillaud, F

    2007-01-01

    The stability of superconducting wires is a crucial task in the design of safe and reliable superconducting magnets. These magnets are prone to premature quenches due to local releases of energy. In order to simulate these energy disturbances, various heater technologies have been developed, such as coated tips, graphite pastes, and inductive coils. The experiments studied in the present work have been performed using a single-mode diode laser with an optical fiber to illuminate the superconducting strand surface. Minimum quench energies and voltage traces at different magnetic flux densities and transport currents have been measured on an LHC-type, Cu/NbTi wire bathed in pool boiling helium I. This paper deals with the numerical analysis of the experimental data. In particular, a coupled electromagnetic and thermal model has been developed to study quench development and propagation, focusing on the influence of heat exchange with liquid helium.

  5. Clean and direct production of acetylene - Coal pyrolysis in a H{sub 2}/Ar plasma jet

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.G.; Xie, K.C. [Taiyuan University of Technology, Taiyuan (China). Inst. of Chemical Engineering and Coal

    2002-06-01

    In order to develop a clean and direct production of acetylene, an H{sub 2}/Ar plasma jet is used to convert coal into acetylene. The efficiency of conversion depends on such factors as the size range of the coal particle, the volatile matter in the coal, and the operating conditions. Experimental results with different coals indicate that volatile content plays an important but not exclusive part in acetylene generation. Higher input power and smaller coal article size are in favor of the formation of acetylene.

  6. Effect of ion mass on pair production in the interaction of an ultraintense laser with overdense plasmas

    CERN Document Server

    Wan, F; Jia, M R; Wang, H Y; Xie, B S

    2016-01-01

    The effect of ion mass on pair production in the interaction of an ultraintense laser with overdense plasmas has been explored by particle-in-cell (PIC) simulation. It is found that the heavier ion mass excites the higher and broader electrostatic field, which is responsible for the enhancement of backward photon number. The pair yields are also reinforced due to the increase of head-on collision of backwards photon with incoming laser. By examining the density evolution and angle distribution of each particle species the origin of pair yields enhancement has been clarified further.

  7. Plasma Kinetics in Electrical Discharge in Mixture of Air, Water and Ethanol Vapors for Hydrogen Enriched Syngas Production

    CERN Document Server

    Shchedrin, A I; Ryabtsev, A V; Chernyak, V Ya; Yukhymenko, V V; Olszewski, S V; Naumov, V V; Prysiazhnevych, I V; Solomenko, E V; Demchina, V P; Kudryavtsev, V S

    2008-01-01

    The complex theoretical and experimental investigation of plasma kinetics of the electric discharge in the mixture of air and ethanol-water vapors is carried out. The discharge was burning in the cavity, formed by air jets pumping between electrodes, placed in aqueous ethanol solution. It is found out that the hydrogen yield from the discharge is maximal in the case when ethanol and water in the solution are in equal amounts. It is shown that the hydrogen production increases with the discharge power and reaches the saturation at high value. The concentrations of the main stable gas-phase components, measured experimentally and calculated numerically, agree well in the most cases.

  8. Biologic variability in plasma glucose, hemoglobin A1c, and advanced glycation end products associated with diabetes complications.

    Science.gov (United States)

    Leslie, R David G; Cohen, Robert M

    2009-07-01

    Plasma glucose plays a key role in the complications of diabetes mellitus. Hemoglobin A1c (HbA1c) and circulating concentrations of advanced glycation end products (AGEs) are central to diabetes clinical care and pathophysiology. However, there is evidence for variation between individuals in the relationship of plasma glucose to both these measures and to specific complications. The glycation gap (GG) and hemoglobin glycation index represent tools for quantitating the variability in the relationship between plasma glucose and HbA1c useful for identification of underlying mechanisms. Recent evidence demonstrates the heritability of HbA1c, the GG, and AGEs, yet not of glycated serum proteins. There has been tremendous effort devoted to identifying the heritable basis of types 1 and 2 diabetes; however, studies on the heritable contributors to these mediators of glucose effect on complications are only beginning. New evidence for normal biologic variation in the distribution of glucose into the red blood cell (RBC) intracellular compartment and RBC lifespan in people with and without diabetes represent candidates for heritable mechanisms and contributors to the rise in HbA1c with age. Taken as a whole, genetic and mechanistic evidence suggests new potential targets for complications prevention and improvement in complications risk estimation. These observations could help tilt the risk-benefit balance in glycemic control toward a more beneficial outcome.

  9. Relationship between late embryonic mortality and the increase in plasma advanced oxidised protein products (AOPP) in dairy cows.

    Science.gov (United States)

    Celi, Pietro; Merlo, Mariacristina; Da Dalt, Laura; Stefani, Annalisa; Barbato, Olimpia; Gabai, Gianfranco

    2011-01-01

    The involvement of protein oxidation in embryonic mortality (EM) has been poorly investigated in cows. Advanced oxidation protein products (AOPP) are markers of protein oxidation generated by activated neutrophils and involved in inflammation. The aim of this work was to study AOPP in cow plasma and their relationship with late EM. The outcomes of 158 artificial inseminations (AI) were examined in 72 cows, which were classified ex post on the basis of blood progesterone and pregnancy-associated glycoprotein concentrations and clinical confirmation of pregnancy into the following categories: (1) positive (AI+, resulted in pregnancy, n=58), (2) negative (AI-, did not result in pregnancy, n=86) and (3) embryonic mortality (EM, n=14). Plasma protein fractions, malondialdehyde (MDA), total glutathione and AOPP were measured at AI (Day 0) and on Days 15, 28, 35, 45 and 60. MDA was significantly higher in EM than AI+ and AI- animals on Day 45, and than AI+ animals on Day 60 (P<0.05). Mean plasma AOPP concentrations were significantly higher in the EM group (P<0.01) and the ratio of AOPP:albumin was significantly higher in the EM group on Days 15, 28, 45 and 60 (P<0.05). Based on the temporal pattern of the AOPP:albumin ratio, we propose that oxidative stress is implicated in and may possibly be a cause of EM.

  10. Plasma Levels of Soluble Receptor for Advanced Glycation End Products and Coronary Atherosclerosis: Possible Correlation with Clinical Presentation

    Directory of Open Access Journals (Sweden)

    Colomba Falcone

    2013-01-01

    Full Text Available Receptor for Advanced Glycation End-products (RAGE is a multi-ligand receptor ubiquitous present on epithelial, neuronal, vascular and inflammatory cells, usually expressed at low levels in homeostasis and to increased degrees at sites of stress or injury. The aim of the present study was to evaluate sRAGE plasma levels in patients with Acute Coronary Syndrome (ACS and to assess its diagnostic efficacy in identification of patients with acute events. Plasma levels of sRAGE were determined in 860 patients with Coronary Artery Disease (CAD: 530 patients presented stable angina and 330 were observed during acute ischemic event (147 with unstable angina and 183 with myocardial infarction. sRAGE plasma levels were significantly lower in patients with ACS than in patients with stable angina: [median 584 pg/mL (IQR: 266–851 pg/mL in MI patients, median 769 pg/mL (IQR: 394–987 pg/mL in patients with unstable angina, median 834 pg/mL (IQR 630–1005 pg/mL in patients with stable angina; P<0.001]. sRAGE levels did not differ among ACS patients stratified by the extent of coronary artery disease. In conclusion, this study confirm the role of sRAGE in activation and progression of inflammatory process and suggests the possibility that sRAGE can be considered an indicator of destabilization of vulnerable plaque.

  11. Impairment of liver synthetic function and the production of plasma proteins in primary breast cancer patients on doxorubicincyclophosphamide (AC) protocol.

    Science.gov (United States)

    Saleem, Zikria; Ahmad, Mobasher; Hashmi, Furqan Khurshid; Saeed, Hamid; Aziz, Muhammad Tahir

    2016-09-01

    Doxorubicin and Cyclophosphamide (AC protocol) combination is usually considered as a first line therapy in newly diagnosed breast cancer patients. Thus, a retrospective observational study was conducted to monitor the effect of AC protocol on liver synthetic functions and production of plasma proteins in breast cancer patients, reporting to specialized cancer care hospital of Lahore, Pakistan. A total of 75 patients (n=75) on AC protocol with breast cancer were observed in this study. The patient data including age, gender, body surface area, dosage, disease status and laboratory biochemical values were recorded by reviewing historical treatment records. Pre-treatment values were taken as baseline values for albumin, globulin, blood urea nitrogen (BUN), albumin/globulin (A/G) ratio and total proteins. The baseline values were compared after each cycle of by applying ANOVA using statistical tool SPSS® version 21. The plasma levels of blood urea nitrogen (BUN), total protein and globulin dropped significantly (p0.05). The A/G ratio level increased (pliver synthetic functions as observed by decreased blood urea nitrogen (BUN) and plasma protein levels.

  12. One-step phenol production from a water-toluene mixture using radio frequency in-liquid plasma

    Science.gov (United States)

    Muhammad, AGUNG; Shinfuku, NOMURA; Shinobu, MUKASA; Hiromichi, TOYOTA; Otsuka, KAZUHIKO; Hidekazu, GOTO

    2017-05-01

    The objectives of this research were to understand the process of converting toluene into phenol in a one-step process directly from a water-toluene mixture using the plasma in-liquid method. Experiments were conducted using 27.12 MHz radio frequency (RF) in-liquid plasma to decompose a solution of 30% toluene. Based on the experimental results as evaluated using gas chromatography-mass spectrometry (GC-MS), along with additional analysis by the Gaussian calculation, density functional theory (DFT) hybrid exchange-correlational functional (B3LYP) and 6-311G basis, the phenol generated from toluene was quantified including any by-products. In the experiment, it was found that OH radicals from water molecules produced using RF in-liquid plasma play a significant role in the chemical reaction with toluene. The experimental results suggest that phenol can be directly produced from a water-toluene mixture. The maximum phenol yields were 0.0013% and 0.0038% for irradiation times of 30 s and 60 s, respectively, at 120 W.

  13. Experimental and computational study of the injection of antiprotons into a positron plasma for antihydrogen production

    Science.gov (United States)

    Amole, C.; Ashkezari, M. D.; Baquero-Ruiz, M.; Bertsche, W.; Butler, E.; Capra, A.; Cesar, C. L.; Charlton, M.; Deller, A.; Eriksson, S.; Fajans, J.; Friesen, T.; Fujiwara, M. C.; Gill, D. R.; Gutierrez, A.; Hangst, J. S.; Hardy, W. N.; Hayden, M. E.; Isaac, C. A.; Jonsell, S.; Kurchaninov, L.; Little, A.; Madsen, N.; McKenna, J. T. K.; Menary, S.; Napoli, S. C.; Olchanski, K.; Olin, A.; Pusa, P.; Rasmussen, C. Ø.; Robicheaux, F.; Sarid, E.; Shields, C. R.; Silveira, D. M.; So, C.; Stracka, S.; Thompson, R. I.; van der Werf, D. P.; Wurtele, J. S.; Zhmoginov, A.; Friedland, L.

    2013-04-01

    One of the goals of synthesizing and trapping antihydrogen is to study the validity of charge-parity-time symmetry through precision spectroscopy on the anti-atoms, but the trapping yield achieved in recent experiments must be significantly improved before this can be realized. Antihydrogen atoms are commonly produced by mixing antiprotons and positrons stored in a nested Penning-Malmberg trap, which was achieved in ALPHA by an autoresonant excitation of the antiprotons, injecting them into the positron plasma. In this work, a hybrid numerical model is developed to simulate antiproton and positron dynamics during the mixing process. The simulation is benchmarked against other numerical and analytic models, as well as experimental measurements. The autoresonant injection scheme and an alternative scheme are compared numerically over a range of plasma parameters which can be reached in current and upcoming antihydrogen experiments, and the latter scheme is seen to offer significant improvement in trapping yield as the number of available antiprotons increases.

  14. Cylindrical dielectric barrier discharge plasma catalytic effect on chemical methods of silver nano-particle production

    Science.gov (United States)

    Bahrami, Zahra; Khani, Mohammad Reza; Shokri, Babak

    2016-11-01

    In this study, cylindrical dielectric barrier discharge plasma was used to study the catalytic effect on chemical methods of silver nano-particles for the first time. In this method, the processing time is short and the temperature of reaction is low. Also, the reactor is very simple, inexpensive, and accessible. In this work, pure AgNO3 as the precursor agent and poly vinyl pyrrolidone as the macromolecular surfactant were dissolved in ethanol as the solvent. UV-Vis and XRD were used to identify the colloidal and powder nano-particles, respectively. Optical emission spectroscopy was also used to identify the active species in plasma. Effects of gas flow rate, voltage, volume of solution, and processing time were also studied. Moreover, TEM and SEM images presented the mean diameter of nano-particle size around 10 to 20 nm. The results have been very promising.

  15. Plasma production by helicon waves with single mode number in low magnetic fields

    CERN Document Server

    Sato, G; Hatakeyama, R; Sato, Genta; Oohara, Wataru; Hatakeyama, Rikizo

    2004-01-01

    Radio-frequency discharges are performed in low magnetic fields (0-10 mT) using three types of helicon-wave exciting antennas with the azimuthal mode number of $|m|$ = 1. The most pronounced peak of plasma density is generated in the case of phased helical antenna at only a few mT, where the helicon wave with $|m| = 1$ is purely excited and propagates. An analysis based on the dispersion relation well explains the density-peak phenomenon in terms of the correspondence between the antenna one-wavelength and the helicon wavelength. The $m=+1$ helicon wave propagates even in high magnetic fields where the density peaks are not observed, but the $m=-1$ helicon wave disappers. It is expected theoretically that the $m=-1$ helicon wave shows cutoff behavior in a low density region, [M. Kramer, Phys. Plasmas 6, 1052 (1999)], and the cutoff of $m=-1$ helicon wave experimentally observed coincides with the calculated one.

  16. Experimental and computational study of the injection of antiprotons into a positron plasma for antihydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Amole, C.; Capra, A.; Menary, S. [Department of Physics and Astronomy, York University, Toronto, M3J 1P3 Ontario (Canada); Ashkezari, M. D.; Hayden, M. E. [Department of Physics, Simon Fraser University, Burnaby, V5A 1S6 British Columbia (Canada); Baquero-Ruiz, M.; Little, A.; So, C.; Zhmoginov, A. [Department of Physics, University of California, Berkeley, California 94720 (United States); Bertsche, W. [Department of Physics, College of Science, Swansea University, SA2 8PP Swansea (United Kingdom); School of Physics and Astronomy, University of Manchester, M13 9PL Manchester (United Kingdom); Daresbury Laboratory, Cockcroft Institute, WA4 4AD Warrington (United Kingdom); Butler, E. [Physics Department, CERN, CH-1211 Geneva 23 (Switzerland); Cesar, C. L.; Silveira, D. M. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941 (Brazil); Charlton, M.; Deller, A.; Eriksson, S.; Isaac, C. A.; Madsen, N.; Napoli, S. C.; Shields, C. R. [Department of Physics, College of Science, Swansea University, SA2 8PP Swansea (United Kingdom); Collaboration: ALPHA Collaboration; and others

    2013-04-15

    One of the goals of synthesizing and trapping antihydrogen is to study the validity of charge-parity-time symmetry through precision spectroscopy on the anti-atoms, but the trapping yield achieved in recent experiments must be significantly improved before this can be realized. Antihydrogen atoms are commonly produced by mixing antiprotons and positrons stored in a nested Penning-Malmberg trap, which was achieved in ALPHA by an autoresonant excitation of the antiprotons, injecting them into the positron plasma. In this work, a hybrid numerical model is developed to simulate antiproton and positron dynamics during the mixing process. The simulation is benchmarked against other numerical and analytic models, as well as experimental measurements. The autoresonant injection scheme and an alternative scheme are compared numerically over a range of plasma parameters which can be reached in current and upcoming antihydrogen experiments, and the latter scheme is seen to offer significant improvement in trapping yield as the number of available antiprotons increases.

  17. Plasma and Beam Production Experiments with HYBRIS, aMicrowave-assisted H- Ion

    Energy Technology Data Exchange (ETDEWEB)

    Keller, R. AUTHOR-Kwan, S.; Hahto, S.; Regis, M.; Wallig, J.

    2006-09-13

    A two-stage ion source concept had been presented a few years ago, consisting of a proven H- ion source and a 2.45-GHz Electron Cyclotron-Resonance (ECR) type ion source, here used as a plasma cathode. This paper describes the experimental development path pursued at Lawrence Berkeley National Laboratory, from the early concept to a working unit that produces plasma in both stages and creates a negative particle beam. Without cesiation applied to the second stage, the H{sup -} fraction of this beam is very low, yielding 75 micro-amperes of extracted ion beam current at best. The apparent limitations of this approach and envisaged improvements are discussed.

  18. PIC simulations of the production of high-quality electron beams via laser-plasma interaction

    Energy Technology Data Exchange (ETDEWEB)

    Benedetti, C. [Department of Physics, University of Bologna and INFN/Bologna, Via Irnerio 46, 40126 Bologna (Italy)], E-mail: carlo.benedetti@bo.infn.it; Londrillo, P. [INAF, Osservatorio Astronomico di Bologna, Via Ranzani 1, 40127 Bologna (Italy); Petrillo, V.; Serafini, L. [INFN/Milano, Via Celoria 14, 10133 Milano (Italy); Sgattoni, A. [Department of Physics, University of Bologna and INFN/Bologna, Via Irnerio 46, 40126 Bologna (Italy); Tomassini, P. [INFN/Milano, Via Celoria 14, 10133 Milano (Italy); Turchetti, G. [Department of Physics, University of Bologna and INFN/Bologna, Via Irnerio 46, 40126 Bologna (Italy)

    2009-09-01

    We present some numerical studies and parameter scans performed with the electromagnetic, relativistic, fully self-consistent Particle-In-Cell (PIC) code ALaDyn (Acceleration by LAser and DYNamics of charged particles), concerning the generation of a low emittance, high charge and low momentum spread electron bunch from laser-plasma interaction in the Laser WakeField Acceleration (LWFA) regime, in view of achieving beam brightness of interest for FEL applications.

  19. Baryon stopping and quark-gluon plasma production at RHIC and LHC

    Energy Technology Data Exchange (ETDEWEB)

    Lyakhov, K.

    2008-08-15

    Strong chromofields developed at early stages of relativistic heavy-ion collisions give rise to the collective deceleration of net baryons from colliding nuclei. We have solved classical equations of motion for baryonic slabs under the action of time-dependent chromofield. We have studied sensitivity of the slab trajectories and their final rapidities to the initial strength and decay pattern of the chromofield as well as to the back reaction of produced plasma. This mechanism can naturally explain significant baryon stopping observed at RHIC, an average rapidity loss left angle {delta}y right angle {approx} 2. Using a Bjorken hydrodynamical model with particle producing source we also study the evolution of partonic plasma produced as the result of chromofield decay. Due to the delayed formation and expansion of plasma its maximum energy density is much lower than the initial energy density of the chromofield. It is shown that the net-baryon and produced parton distributions are strongly correlated in the rapidity space. The shape of net-baryon spectra in midrapidity region found in the BRAHMS experiment cannot be reproduced by only one value of chromofield energy density parameter {epsilon}{sub 0}, even if one takes into account novel mechanisms as fluctuations of color charges generated on the slab surface, and weak interaction of baryon-rich matter with produced plasma. The further step to improve our results is to take into account rapidity dependence of saturation momentum as explained in thesis. Different values of parameter {epsilon}{sub 0} has been tried for different variants of chromofield decay to fit BRAHMS data for net-baryon rapidity distribution. In accordance with our analysis, data for fragmentation region correspond to the lower chromofield energy densities than mid-rapidity region. {chi}{sup 2} analysis favors power-law of chromofield decay with corresponding initial chromofield energy density of order {epsilon}{sub f}=30 GeV/fm{sup 3}. (orig.)

  20. Laboratory experiments investigating magnetic field production via the Weibel instability in interpenetrating plasma flows

    Science.gov (United States)

    Huntington, Channing; Fiuza, Frederico; Ross, James Steven; Zylstra, Alex; Pollock, Brad; Drake, R. Paul; Froula, Dustin; Gregori, Gianluca; Kugland, Nathan; Kuranz, Carolyn; Levy, Matthew; Li, Chikang; Meinecke, Jena; Petrasso, Richard; Remington, Bruce; Ryutov, Dmitri; Sakawa, Youichi; Spitkovsky, Anatoly; Takabe, Hideke; Turnbull, David; Park, Hye-Sook

    2015-08-01

    Astrophysical collisionless shocks are often associated with the presence of strong magnetic fields in a plasma flow. The magnetic fields required for shock formation may either be initially present, for example in supernova remnants or young galaxies, or they may be self-generated in systems such as gamma-ray bursts (GRBs). In the case of GRB outflows, the intense magnetic fields are greater than those seeded by the GRB progenitor or produced by misaligned density and temperature gradients in the plasma flow (the Biermann-battery effect). The Weibel instability is one candidate mechanism for the generation of sufficiently strong fields to create a collisionless shock. Despite their crucial role in astrophysical systems, observation of the magnetic fields produced by Weibel instabilities in experiments has been challenging. Using a proton probe to directly image electromagnetic fields, we present evidence of Weibel-generated magnetic fields that grow in opposing, initially unmagnetized plasma flows from laser-driven laboratory experiments. Three-dimensional particle-in-cell simulations reveal that the instability efficiently extracts energy from the plasma flows, and that the self-generated magnetic energy reaches a few percent of the total energy in the system. This result demonstrates an experimental platform suitable for the investigation of a wide range of astrophysical phenomena, including collisionless shock formation in supernova remnants, large-scale magnetic field amplification, and the radiation signature from gamma-ray bursts.This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  1. Formation of nitrogen oxides from atmospheric electrodeless microwave plasmas in nitrogen-oxygen mixtures

    Science.gov (United States)

    Lee, Jungwun; Sun, Hojoong; Im, Seong-kyun; Soo Bak, Moon

    2017-08-01

    Electrodeless microwave plasmas were produced in nitrogen-oxygen mixtures at atmospheric pressure to investigate the formation of nitrogen oxides (NOx) from the plasma. The oxygen content in the mixtures is varied in the range of 1%-3%, and the total flowrate is varied in the range of 25-45 slpm while the microwave power is fixed at 2 kW. The rotational and vibrational temperatures of the plasma are measured based on plasma optical emission spectroscopy, and the amount of NOx is measured using a NOx analyzer far downstream from the plasma. The temperatures at the plasma region reach ˜6700 K, and little difference is observed between the rotational and vibrational temperatures as a result of fast vibrational-translational relaxation. Moreover, these temperatures are found to be independent of the flowrate. As the flowrate decreases and the oxygen content in the mixture increases, the level of NOx is increased from 1612 ppm to 9380 ppm. For detailed investigation, plasma kinetic simulations considering trans-rotational, vibrational, and electron temperatures separately are developed and conducted for the plasma region. The level of NOx from the kinetic simulations is found to be considerably smaller than that measured. As the equilibrium mole fraction of NOx is the highest at a temperature of 3120 ± 100 K, with the variation attributable to the composition of species, significant production of NOx is expected to occur at the post-plasma region when the plasma stream is quenched by mixing with the surrounding flow.

  2. Effects of thermal quenching on the breakup of pyroclasts

    Science.gov (United States)

    Patel, A.; Manga, M.; Carey, R. J.; Degruyter, W.; Dufek, J.

    2012-12-01

    It is often assumed that magma fragments when it contacts water. Obsidian chips and glass spheres crack when quenched. Vesicular pyroclasts are made of similar glass, so thermal quenching may cause them to break more easily. We performed a set of experiments on air fall pumice from Medicine Lake, California. Density and texture of similar samples are described in Manga et al., Bull Volc 2010. We made "quenched" samples by heating natural pyroclasts to 600 °C, quenching them in water at 21 °C, drying them at 105 °C, and then cooling them to room temperature. We compare these samples with untreated air fall pumice from the same deposit, hereafter referred to as "regular" pumice. We tested whether quenched pumice would 1) shatter more easily in collisions and 2) abrade faster. Our collision experiment methods are described in Dufek et al., Nature Geoscience 2012. Our abrasion experiment methods are described in Manga et al., Bull Volc 2010. We also tested whether individual clasts lose mass upon quenching and whether they increase in effective wet density. Effective wet density is defined as underwater density of a clast when water occupies part of the pore space. Effective wet density, measured as a function of time after immersion, indicates the volume fraction of the pore space that becomes occupied by water. We compare effective wet density of individual clasts pre-quenching with effective wet density after having been quenched, thoroughly dried and then cooled to room temperature. An increase in effective wet density would suggest that bubble walls had been damaged during quenching, allowing water to occupy the pore space faster. We also compare pre-quenching and post-quenching textures using X-Ray Tomography (XRT) and SEM images. Results from collision experiments show no obvious difference between quenched pumice and regular pumice. Quenched pumice abraded more quickly than regular pumice. We find that 1 to 2 % of mass was lost during quenching. Effective

  3. Explaining jet quenching with perturbative QCD alone

    CERN Document Server

    Zapp, Korinna C; Wiedemann, Urs A

    2011-01-01

    We present a new formulation of jet quenching in perturbative QCD beyond the eikonal approximation. Multiple scattering in the medium is modelled through infra-red-continued (2 -> 2) scattering matrix elements in QCD and the parton shower describing further emissions. The interplay between these processes is arranged in terms of a formation time constraint such that coherent emissions can be treated consistently. Emerging partons are hadronised by the Lund string model, tuned to describe LEP data in conjunction with the parton shower. Based on this picture we obtain a good description of the nuclear modification factor R_AA at RHIC and LHC.

  4. Quench modeling of the ATLAS superconducting toroids

    CERN Document Server

    Gavrilin, A V; ten Kate, H H J

    2001-01-01

    Details of the normal zone propagation and the temperature distribution in the coils of ATLAS toroids under quench are presented. A tailor-made mathematical model and corresponding computer code enable obtainment of computational results for the propagation process over the coils in transverse (turn-to-turn) and longitudinal directions. The slow electromagnetic diffusion into the pure aluminum stabilizer of the toroid's conductor, as well as the essentially transient heat transfer through inter-turn insulation, is appropriately included in the model. The effect of nonuniform distribution of the magnetic field and the thermal links to the coil casing on the temperature gradients within the coils is analyzed in full. (5 refs).

  5. Quenching simulation of steel grinding balls

    Energy Technology Data Exchange (ETDEWEB)

    Zapata-Hernandez, O.; Reyes, L. A.; Camurri, C.; Carrasco, C.; Garza-Monte-de-Oca, F.; Colas, R.

    2015-07-01

    The phase transformations of high carbon steel during quenching and equalizing were modelled using commercial computer packages based on the finite element method and the kinetic transformation of steel. The model was used to predict the temperature and microstructural changes taking place within balls of two different sizes that are used for grinding mineral ores. A good correlation between the temperatures measured by inserted thermocouples and those predicted by the model was obtained after modifying the thermal conductivity of the steel within the temperature domain at which mixed phases are present. The phase transformations predicted were confirmed by metallographic analyses. (Author)

  6. Jet Quenching Measurements with ATLAS at LHC

    CERN Document Server

    Brooks, W K; The ATLAS collaboration

    2009-01-01

    A broad program of measurements is planned for heavy ion collisions in ATLAS. With up to a factor of 30 increase in collision energy compared to existing data, significant new insights are anticipated to be obtained with the first data measured. Global features of the LHC collisions will be accessible with the early data and will set the stage for the precision measurements to follow. ATLAS is particularly well suited for exploration of "jet quenching," the extinction of energetic jets in the hot dense medium. Observations of heavy quark jet suppression will be possible with unprecedented energy reach and statistical precision, potentially yielding new insights into the basic mechanisms involved.

  7. $B_{K}$ from quenched overlap QCD

    CERN Document Server

    Garron, N; Hölbling, C; Lellouch, L P; Rebbi, C

    2003-01-01

    We present an exploratory calculation of the standard model Delta S=2 matrix element relevant for indirect CP violation in K -> pi pi decays. The computation is performed with overlap fermions in the quenched approximation at beta=6.0 on a 16^3x32 lattice. The resulting bare matrix element is renormalized non-perturbatively. Our preliminary result is B_K^{NDR}(2 GeV)=0.61(7), where the error does not yet include an estimate of systematic uncertainties.

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

    Science.gov (United States)

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

    2015-02-20

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

  9. Neutron production in deuterium gas-puff z-pinch with outer plasma shell at current of 3 MA

    Science.gov (United States)

    Cikhardt, J.; Klir, D.; Rezac, K.; Cikhardtova, B.; Kravarik, J.; Kubes, P.; Sila, O.; Shishlov, A. V.; Cherdizov, R. K.; Frusov, F. I.; Kokshenev, V. A.; Kurmaev, N. E.; Labetsky, A. Yu.; Ratakhin, N. A.; Dudkin, G. N.; Garapatsky, A. A.; Padalko, V. N.; Varlachev, V. A.; Turek, K.; Krasa, J.

    2015-11-01

    Z-pinch experiments at the current of about 3 MA were carried out on the GIT-12 generator. The outer plasma shell of deuterium gas-puff was generated by the system of 48 plasma guns. This configuration exhibits a high efficiency of the production of DD fusion neutrons with the yield of above 1012 neutrons produced in a single shot with the duration of about 20 ns. The maximum energy of the neutrons produced in this pulse exceeded 30 MeV. The neutron radiation was measured using scintillation TOF detectors, CR-39 nuclear track detectors, bubble detectors BD-PND and BDS-10000 and by several types of nuclear activation detectors. These diagnostic tools were used to measure the anisotropy of neutron fluence and neutron energy spectra. It allows us to estimate the total number of DD neutrons, the contribution of other nuclear reactions, the amount of scattered neutrons, and other parameters of neutron production. This work was supported by the MSMT grants LH13283, LD14089.

  10. I/asterisk/ /6s 4P/ collisional quenching - Application to the IF 491-nm laser

    Science.gov (United States)

    Hutchison, S. B.; Verdeyen, J. T.; Eden, J. G.

    1981-01-01

    Measurements of the rate constants for quenching of the excited I (6s 4P) states by Ar, Xe, CF39I, UF6, and NF3 are described. Each rate constant is determined by recording the exponential time decay of the excited IF or excited I2 (342 nm) fluorescence in the afterglow of the e-beam-excited plasmas containing Ar, CF3I, NF3, and the desired quenching gas. In addition, further experimental evidence in support of neutral channel formation of excited IF in e-beam-pumped Ar/CF3I/NF3 mixtures is presented. Details of the experimental apparatus and gas handling procedures are given, and the kinetics model developed to interpret the experimental data is described.

  11. Photons and dileptons production in a quark gluon plasma: infrared structure and coherent scattering effects; Production de photons et de dileptons dans un plasma de quarks et de gluons: structure infrarouge et effets coherents

    Energy Technology Data Exchange (ETDEWEB)

    Zaraket, H

    2000-06-01

    This work is devoted to photon and dilepton production in a quark gluon plasma. The theoretical framework in which the study is carried out is Thermal Field Theory, more precisely the hard thermal loop effective theory. Several features of the observables preclude a straightforward application of the effective theory and new tools had to be developed such as the counter term method to avoid double counting. The first part of my study concerns static virtual photon production where I show that important physical contributions are missing in the effective theory at one loop level and hence a two loop calculation is indispensable. Furthermore I give an analytic leading logarithmic estimate of this two loop result showing clearly the insufficiency of the effective theory. The second part of the work focuses on real and quasi real photon production. Again, important contributions arise at two loop level due to collinear divergences. For high mass dilepton the two loop calculation is sufficient. On the other hand, near the light cone photon production rate is non perturbative. Getting closer to the light cone coherent scattering effects (Landau-Pomeranchuk-Migdal effect) arise, which imply the resummation of an infinite series of diagrams. Still nearer the light cone we found a dependence on the non perturbative magnetic mass due to infrared singularities. (author)

  12. Utilizing QFD model to determine quality characteristics of the products and priority needs of customers in the medical industry products (Case Study: Plasma seat product in mashhad`s Sahateb medical equipment company

    Directory of Open Access Journals (Sweden)

    Zeinab Armoun

    2012-10-01

    Full Text Available Quality Function Deployment (QFD as one of the quality engineering methods; originates from market study and product or service customers identification, where by determining their needs; tries to involve them in all stages of product or service development. This study uses QFD method to apply customers’ criteria in production of Coach Plasma in Mashhad`s Sahateb Company. Coach Plasma is used for healthy bloodletting. The proposed study of this paper designed and distributed a questionnaire, which includes identification & determination of customers’ needs and investigation of their satisfaction of manufactured products, while looking for technical and engineering characteristics related to their needs. The Coach Plasma costumers are categorized into two groups of local and external customers. Data collection was done based on available documents, experts opinions, structured interview with managers and questionnaire. Customers’ needs were studied in QFD teams. Collecting essential information such as needs importance degree and competitive benchmarking of customer`s needs, the weight of each need has been evaluated. In this research, House of Quality was used from first matrix of QFD leading to estimation of engineering & technical characteristics in order to enter to the quality deployment matrix. Take a look at obtained results, we could mention the role of each of these external factors in satisfaction of Sahateb Company customers and technical characteristics of the company in providing these factors and the prioritization of the customer's needs.

  13. Dilepton production rate in a hot and magnetized quark-gluon plasma

    CERN Document Server

    Sadooghi, N

    2016-01-01

    The differential multiplicity of dileptons in a hot and magnetized quark-gluon plasma, $\\Delta_{B}\\equiv dN_{B}/d^{4}xd^{4}q$, is derived from first principles. The constant magnetic field $B$ is assumed to be aligned in a fixed spatial direction. It is shown that the anisotropy induced by the $B$ field is mainly reflected in the general structure of photon spectral density function. This is related to the imaginary part of the vacuum polarization tensor, $\\mbox{Im}[\\Pi^{\\mu\

  14. Production of a Uniform ECR Plasma Using Large Diameter Multi Slot Antennas

    OpenAIRE

    上田, 洋子; 寺西, 秀明; 田中, 雅慶; 篠原, 俊二郎; 河合, 良信

    1994-01-01

    A uniform ECR plasma is produced with a multi slot antenna of 280mm in diameter. The radial profile of the ion saturation current density is examined as a function of microwave power and pressure. The radial uniformity of the ion saturation current density is within pm3% over 8 inches in diameter for the input microwave power lkW at pressure of 2mTorr. Furthermore, the deposition of a-Si:H films is attempted on glass substrates using mixture SiH4/He. When the microwave power is increased, the...

  15. Azimuthal anisotropy of π⁰ production in Au+Au collisions at sqrt((s)NN)=200  GeV: path-length dependence of jet quenching and the role of initial geometry.

    Science.gov (United States)

    Adare, A; Afanasiev, S; Aidala, C; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Alexander, J; Aoki, K; Aramaki, Y; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bickley, A A; Bok, J S; Boyle, K; Brooks, M L; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Camacho, C M; Campbell, S; Chen, C-H; Chi, C Y; Chiu, M; Choi, I J; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; Connors, M; Constantin, P; Csanád, M; Csörgo, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Denisov, A; Deshpande, A; Desmond, E J; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Finger, M; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Garishvili, I; Glenn, A; Gong, H; Gonin, M; Goto, Y; Granier de Cassagnac, R; Grau, N; Greene, S V; Grosse Perdekamp, M; Gunji, T; Gustafsson, H-Å; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Hanks, J; Han, R; Hartouni, E P; Haslum, E; Hayano, R; Heffner, M; Hegyi, S; Hemmick, T K; Hester, T; He, X; Hill, J C; Hohlmann, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Ide, J; Ikeda, Y; Imai, K; Inaba, M; Isenhower, D; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Jacak, B V; Jia, J; Jin, J; Johnson, B M; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kang, J H; Kapustinsky, J; Karatsu, K; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kim, B I; Kim, D H; Kim, D J; Kim, E J; Kim, E; Kim, S H; Kim, Y J; Kinney, E; Kiriluk, K; Kiss, A; Kistenev, E; Kochenda, L; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kozlov, A; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K B; Lee, K; Lee, K S; Leitch, M J; Leite, M A L; Leitner, E; Lenzi, B; Liebing, P; Linden Levy, L A; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Li, X; Love, B; Luechtenborg, R; Lynch, D; Maguire, C F; Makdisi, Y I; Malakhov, A; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; Means, N; Meredith, B; Miake, Y; Mignerey, A C; Mikeš, P; Miki, K; Milov, A; Mishra, M; Mitchell, J T; Mohanty, A K; Morino, Y; Morreale, A; Morrison, D P; Moukhanova, T V; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, T; Nakano, K; Newby, J; Nguyen, M; Nouicer, R; Nyanin, A S; O'Brien, E; Oda, S X; Ogilvie, C A; Okada, K; Oka, M; Onuki, Y; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, I H; Park, J; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J-C; Pereira, H; Peresedov, V; Peressounko, D Yu; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Purwar, A K; Qu, H; Rak, J; Rakotozafindrabe, A; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Rosnet, P; Rukoyatkin, P; Ružička, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Semenov, A Yu; Seto, R; Sharma, D; Shein, I; Shibata, T-A; Shigaki, K; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Sparks, N A; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sziklai, J; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tarján, P; Themann, H; Thomas, T L; Togawa, M; Toia, A; Tomášek, L; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Vinogradov, A A; Virius, M; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Wood, J P; Woody, C L; Wright, R M; Wysocki, M; Xie, W; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; Young, G R; Younus, I; You, Z; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zolin, L

    2010-10-01

    We have measured the azimuthal anisotropy of π⁰ production for 1

  16. Azimuthal Anisotropy of π0 Production in Au+Au Collisions at sNN=200GeV: Path-Length Dependence of Jet Quenching and the Role of Initial Geometry

    Science.gov (United States)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Al-Bataineh, H.; Alexander, J.; Aoki, K.; Aramaki, Y.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Barish, K. N.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Baublis, V.; Baumann, C.; Bazilevsky, A.; Belikov, S.; Belmont, R.; Bennett, R.; Berdnikov, A.; Berdnikov, Y.; Bickley, A. A.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Camacho, C. M.; Campbell, S.; Chen, C.-H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Connors, M.; Constantin, P.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Danchev, I.; Das, K.; Datta, A.; David, G.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Dietzsch, O.; Dion, A.; Donadelli, M.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; Dutta, D.; Edwards, S.; Efremenko, Y. V.; Ellinghaus, F.; Engelmore, T.; Enokizono, A.; En'Yo, H.; Esumi, S.; Fadem, B.; Fields, D. E.; Finger, M., Jr.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Garishvili, I.; Glenn, A.; Gong, H.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gunji, T.; Gustafsson, H.-Å.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamblen, J.; Hanks, J.; Han, R.; Hartouni, E. P.; Haslum, E.; Hayano, R.; Heffner, M.; Hegyi, S.; Hemmick, T. K.; Hester, T.; He, X.; Hill, J. C.; Hohlmann, M.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hornback, D.; Huang, S.; Ichihara, T.; Ichimiya, R.; Ide, J.; Ikeda, Y.; Imai, K.; Inaba, M.; Isenhower, D.; Ishihara, M.; Isobe, T.; Issah, M.; Isupov, A.; Ivanischev, D.; Jacak, B. V.; Jia, J.; Jin, J.; Johnson, B. M.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kametani, S.; Kamihara, N.; Kamin, J.; Kang, J. H.; Kapustinsky, J.; Karatsu, K.; Kawall, D.; Kawashima, M.; Kazantsev, A. V.; Kempel, T.; Khanzadeev, A.; Kijima, K. M.; Kim, B. I.; Kim, D. H.; Kim, D. J.; Kim, E. J.; Kim, E.; Kim, S. H.; Kim, Y. J.; Kinney, E.; Kiriluk, K.; Kiss, Á.; Kistenev, E.; Kochenda, L.; Komkov, B.; Konno, M.; Koster, J.; Kotchetkov, D.; Kozlov, A.; Král, A.; Kravitz, A.; Kunde, G. J.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, D. M.; Lee, J.; Lee, K. B.; Lee, K.; Lee, K. S.; Leitch, M. J.; Leite, M. A. L.; Leitner, E.; Lenzi, B.; Liebing, P.; Linden Levy, L. A.; Liška, T.; Litvinenko, A.; Liu, H.; Liu, M. X.; Li, X.; Love, B.; Luechtenborg, R.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Malakhov, A.; Malik, M. D.; Manko, V. I.; Mannel, E.; Mao, Y.; Masui, H.; Matathias, F.; McCumber, M.; McGaughey, P. L.; Means, N.; Meredith, B.; Miake, Y.; Mignerey, A. C.; Mikeš, P.; Miki, K.; Milov, A.; Mishra, M.; Mitchell, J. T.; Mohanty, A. K.; Morino, Y.; Morreale, A.; Morrison, D. P.; Moukhanova, T. V.; Murata, J.; Nagamiya, S.; Nagle, J. L.; Naglis, M.; Nagy, M. I.; Nakagawa, I.; Nakamiya, Y.; Nakamura, T.; Nakano, K.; Newby, J.; Nguyen, M.; Nouicer, R.; Nyanin, A. S.; O'Brien, E.; Oda, S. X.; Ogilvie, C. A.; Okada, K.; Oka, M.; Onuki, Y.; Oskarsson, A.; Ouchida, M.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, I. H.; Park, J.; Park, S. K.; Park, W. J.; Pate, S. F.; Pei, H.; Peng, J.-C.; Pereira, H.; Peresedov, V.; Peressounko, D. Yu.; Pinkenburg, C.; Pisani, R. P.; Proissl, M.; Purschke, M. L.; Purwar, A. K.; Qu, H.; Rak, J.; Rakotozafindrabe, A.; Ravinovich, I.; Read, K. F.; Reygers, K.; Riabov, V.; Riabov, Y.; Richardson, E.; Roach, D.; Roche, G.; Rolnick, S. D.; Rosati, M.; Rosen, C. A.; Rosendahl, S. S. E.; Rosnet, P.; Rukoyatkin, P.; Ružička, P.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sakashita, K.; Samsonov, V.; Sano, S.; Sato, T.; Sawada, S.; Sedgwick, K.; Seele, J.; Seidl, R.; Semenov, A. Yu.; Seto, R.; Sharma, D.; Shein, I.; Shibata, T.-A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Silvestre, C.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Slunečka, M.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Sourikova, I. V.; Sparks, N. A.; Stankus, P. W.; Stenlund, E.; Stoll, S. P.; Sugitate, T.; Sukhanov, A.; Sziklai, J.; Takagui, E. M.; Taketani, A.; Tanabe, R.; Tanaka, Y.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tarján, P.; Themann, H.; Thomas, T. L.; Togawa, M.; Toia, A.; Tomášek, L.; Torii, H.; Towell, R. S.; Tserruya, I.; Tsuchimoto, Y.; Vale, C.; Valle, H.; van Hecke, H. W.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Vinogradov, A. A.; Virius, M.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Wei, F.; Wei, R.; Wessels, J.; White, S. N.; Winter, D.; Wood, J. P.; Woody, C. L.; Wright, R. M.; Wysocki, M.; Xie, W.; Yamaguchi, Y. L.; Yamaura, K.; Yang, R.; Yanovich, A.; Ying, J.; Yokkaichi, S.; Young, G. R.; Younus, I.; You, Z.; Yushmanov, I. E.; Zajc, W. A.; Zhang, C.; Zhou, S.; Zolin, L.; PHENIX Collaboration

    2010-10-01

    We have measured the azimuthal anisotropy of π0 production for 1

  17. Quench dynamics in SRF cavities: can we locate the quench origin with 2nd sound?

    Energy Technology Data Exchange (ETDEWEB)

    Maximenko, Yulia; /Moscow, MIPT; Segatskov, Dmitri A.; /Fermilab

    2011-03-01

    A newly developed method of locating quenches in SRF cavities by detecting second-sound waves has been gaining popularity in SRF laboratories. The technique is based on measurements of time delays between the quench as determined by the RF system and arrival of the second-sound wave to the multiple detectors placed around the cavity in superfluid helium. Unlike multi-channel temperature mapping, this approach requires only a few sensors and simple readout electronics; it can be used with SRF cavities of almost arbitrary shape. One of its drawbacks is that being an indirect method it requires one to solve an inverse problem to find the location of a quench. We tried to solve this inverse problem by using a parametric forward model. By analyzing the data we found that the approximation where the second-sound emitter is a near-singular source does not describe the physical system well enough. A time-dependent analysis of the quench process can help us to put forward a more adequate model. We present here our current algorithm to solve the inverse problem and discuss the experimental results.

  18. Higher plasma soluble Receptor for Advanced Glycation End Products (sRAGE) levels are associated with incident cardiovascular disease and all-cause mortality in type 1 diabetes

    DEFF Research Database (Denmark)

    Nin, Johanna W M; Jorsal, Anders; Ferreira, Isabel;

    2010-01-01

    To investigate the associations of plasma levels of soluble receptor for advanced glycation end products (sRAGE) with incident cardiovascular disease (CVD) and all-cause mortality in type 1 diabetes and the extent to which any such associations could be explained by endothelial and renal dysfunct......To investigate the associations of plasma levels of soluble receptor for advanced glycation end products (sRAGE) with incident cardiovascular disease (CVD) and all-cause mortality in type 1 diabetes and the extent to which any such associations could be explained by endothelial and renal...... dysfunction, low-grade inflammation, arterial stiffness, and advanced glycation end products (AGEs)....

  19. The Receptor for Advanced Glycation End Products (Rage) and Its Ligands in Plasma and Infrainguinal Bypass Vein.

    Science.gov (United States)

    Malmstedt, J; Frebelius, S; Lengquist, M; Jörneskog, G; Wang, J; Swedenborg, J

    2016-04-01

    The aim was to investigate whether RAGE and its ligands are associated with infrainguinal bypass outcome in patients with and without diabetes. This was a prospective observational cohort. Patients (n = 68) with (n = 38) and without (n = 30) diabetes undergoing infrainguinal vein bypass for peripheral arterial disease were followed for 3 years. Endosecretory RAGE (esRAGE), S100A12, advanced glycation end products, and carboxymethyl-lysine (CML) were determined in plasma using ELISA. The influence of plasma levels on the main outcome (amputation free survival) was evaluated using Cox proportional hazard analysis. Plasma esRAGE, CML, and S100A12 in healthy controls (n = 30) without cardiovascular disease matched for sex and age were compared with patients, using the Mann-Whitney U test. Veins from bypass surgery procedures were stained and S100A12, RAGE, AGE, and CML were determined using immunohistochemistry. Forty-six patients survived with an intact leg during follow up. Seventeen died (median survival time 702 days, IQR 188-899 day), and six had amputations. High plasma S100A12 was associated with reduced amputation free survival (hazard ratio [HR] 2.99; 95% CI 1.24-7.24) when comparing levels above the 75th percentile with levels below. The increased risk was unchanged adjusting for age, sex, and diabetes. Diabetic patients had higher plasma S100A12 (11.75 ng/mL; 95% CI 8.12-15.38 ng/mL) than non-diabetic patients (5.0141 ng/mL; 95% CI 3.62-6.41 ng/mL), whereas plasma CML, esRAGE, and AGE were similar. Plasma CML and S100A12 were higher in patients than in controls (1.25 μg/mL, 95% CI 1.18-1.32 μg/mL vs. 0.8925 μg/mL, 95% CI 0.82-0.96 μg/mL; and 8.7 μg/mL, 95% CI 6.52-10.95 μg/mL vs. 3.47 μg/mL, 95% CI 2.95-3.99 μg/mL, respectively). The proportion of vein tissue stained for AGE (21%), RAGE (5%), CML (9%) and S100A12 (3%), were similar in patients with and without diabetes. Plasma S100A12 and CML are elevated in peripheral arterial disease and markers of

  20. Heavy flavours production in quark-gluon plasma formed in high energy nuclear reactions

    Science.gov (United States)

    Kloskinski, J.

    1985-01-01

    Results on compression and temperatures of nuclear fireballs and on relative yield of strange and charmed hadrons are given . The results show that temperatures above 300 MeV and large compressions are unlikely achieved in average heavy ion collision. In consequence, thermal production of charm is low. Strange particle production is, however, substantial and indicates clear temperature - threshold behavior.

  1. Holographic quenches towards a Lifshitz point

    CERN Document Server

    Camilo, Giancarlo; Abdalla, Elcio

    2015-01-01

    We use the holographic duality to study quantum quenches of a strongly coupled CFT that drive the theory towards a non-relativistic fixed point with Lifshitz scaling. We consider the case of a Lifshitz dynamical exponent $z$ close to unity, where the non-relativistic field theory can be understood as a specific deformation of the corresponding CFT and, hence, the standard holographic dictionary can be applied. On the gravity side this amounts to finding a dynamical bulk solution which interpolates between AdS and Lishitz spacetimes as time evolves. We show that an asymptotically Lifshitz black hole is always formed in the final state. This indicates that it is impossible to reach the vacuum state of the Lifshitz theory from the CFT vacuum as a result of the proposed quenching mechanism. The nonequilibrium dynamics following the breaking of the relativistic scaling symmetry is also probed using both local and non-local observables. In particular, we conclude that the equilibration process happens in a top-down...

  2. Heat transfer model for quenching by submerging

    Energy Technology Data Exchange (ETDEWEB)

    Passarella, D N; Varas, F [Departamento de Matematica Aplicada II, E.T.S. de Ing. de Telecomunicacion, Universidad de Vigo, Campus Marcosende, 36310 Vigo (Spain); MartIn, E B, E-mail: diego@dma.uvigo.es, E-mail: fvaras@uvigo.es, E-mail: emortega@uvigo.es [Area de Mecanica de Fluidos, E.T.S. de Ing. Industriales, Universidad de Vigo, Campus Marcosende, 36310 Vigo (Spain)

    2011-05-01

    In quenching by submerging the workpiece is cooled due to vaporization, convective flow and interaction of both mechanisms. The dynamics of these phenomena is very complex and the corresponding heat fluxes are strongly dependent on local flow variables such as velocity of fluid and vapor fraction. This local dependence may produce very different cooling rates along the piece, responsible for inappropriate metallurgical transformations, variability of material properties and residual stresses. In order to obtain an accurate description of cooling during quenching, a mathematical model of heat transfer is presented here. The model is based on the drift-flux mixture-model for multiphase flows, including an equation of conservation of energy for the liquid phase and specific boundary conditions that account for evaporation and presence of vapor phase on the surface of the piece. The model was implemented on Comsol Multiphysics software. Generation of appropriate initial and boundary conditions, as well as numerical resolution details, is briefly discussed. To test the model, a simple flow condition was analyzed. The effect of vapor fraction on heat transfer is assessed. The presence of the typical vapor blanket and its collapse can be recovered by the model, and its effect on the cooling rates on different parts of the piece is analyzed. Comparisons between numerical results and data from literature are made.

  3. Quench thresholds in operational superconducting magnets

    Energy Technology Data Exchange (ETDEWEB)

    Allinger, J; Danby, G; Foelsche, H; Jackson, J; Lowenstein, D; Prodell, A; Weng, W

    1978-01-01

    Superconducting magnets exposed to intense primary proton beams in high energy physics applications are subject to potentially extreme heat deposition. The beam power density, its duration and spatial distribution, the current density in the superconductor and, potentially, in the normal metal substrate, as well as the construction and cooling details of the magnet, are all relevant parameters. An extension of some earlier work is discussed in which 28.5 GeV/c proton beams with up to 50 k joules of energy were targeted upstream from a 4 m long, 4 T dipole magnet used to deflect the protons through an angle of 8/sup 0/. Quench thresholds much greater than the enthalpy limit of the magnet materials were observed. In the beam exposure experiment described, intense beams of 1.5 GeV/c protons have been deflected directly into the magnet coil at relatively steep angles of incidence. The magnet quench threshold was studied by varying the beam currents and beam sizes.

  4. Quorum Quenching Revisited—From Signal Decays to Signalling Confusion

    Directory of Open Access Journals (Sweden)

    Kok-Gan Chan

    2012-04-01

    Full Text Available In a polymicrobial community, while some bacteria are communicating with neighboring cells (quorum sensing, others are interrupting the communication (quorum quenching, thus creating a constant arms race between intercellular communication. In the past decade, numerous quorum quenching enzymes have been found and initially thought to inactivate the signalling molecules. Though this is widely accepted, the actual roles of these quorum quenching enzymes are now being uncovered. Recent evidence extends the role of quorum quenching to detoxification or metabolism of signalling molecules as food and energy source; this includes “signalling confusion”, a term coined in this paper to refer to the phenomenon of non-destructive modification of signalling molecules. While quorum quenching has been explored as a novel anti-infective therapy targeting, quorum sensing evidence begins to show the development of resistance against quorum quenching.

  5. System and method for quench protection of a superconductor

    Science.gov (United States)

    Huang, Xianrui; Sivasubramaniam, Kiruba Haran; Bray, James William; Ryan, David Thomas

    2008-03-11

    A system and method for protecting a superconductor from a quench condition. A quench protection system is provided to protect the superconductor from damage due to a quench condition. The quench protection system comprises a voltage detector operable to detect voltage across the superconductor. The system also comprises a frequency filter coupled to the voltage detector. The frequency filter is operable to couple voltage signals to a control circuit that are representative of a rise in superconductor voltage caused by a quench condition and to block voltage signals that are not. The system is operable to detect whether a quench condition exists in the superconductor based on the voltage signal received via the frequency filter and to initiate a protective action in response.

  6. Bridging global and local quantum quenches in conformal field theories

    CERN Document Server

    Wen, Xueda

    2016-01-01

    Entanglement evolutions after a global quantum quench and a local quantum quench in 1+1 dimensional conformal field theories (CFTs) show qualitatively different behaviors, and are studied within two different setups. In this work, we bridge global and local quantum quenches in (1+1)-d CFTs in the same setup, by studying the entanglement evolution from a specific inhomogeneous initial state. By utilizing conformal mappings, this inhomogeneous quantum quench is analytically solvable. It is found that the entanglement evolution shows a global quantum quench feature in the short time limit, and a local quantum quench feature in the long time limit. The same features are observed in single-point correlation functions of primary fields. We provide a clear physical picture for the underlying reason.

  7. Variation of Quench Propagation Velocities in YBCO Cables

    CERN Document Server

    Härö, E.; Stenvall, A.; 10.1007/s10948-015-2976-y

    2015-01-01

    changes during the quench. Due to the large temperature margin between the operation and the current sharing temperatures, the normal zone does not propagate with the temperature front. This means that the temperature will rise in a considerably larger volume when compared to the quenched volume. Thus, the evolution of the temperature distribution below current sharing temperature Tcs after the quench onset affects the normal zone propagation velocity in HTS more than in LTS coils. This can be seen as an acceleration of the quench propagation velocities while the quench evolves when margin to Tcs is high. In this paper we scrutinize quench propagation in a stack of YBCO cables with an in-house finite element method software which solves the heat diffusion equation. We compute the longitudinal and transverse normal zone propagation velocities at various distances from the hot spot to demonstrate the distance-variation...

  8. Accelerator Magnet Quench Heater Technology and Quality Control Tests for the LHC High Luminosity Upgrade

    CERN Document Server

    Meuter, Florian

    The High Luminosity upgrade of the Large Hadron Collider (HL-LHC) foresees the installation of new superconducting Nb3Sn magnets. For the protection of these magnets, quench heaters are placed on the magnet coils. The quench heater circuits are chemically etched from a stainless steel foil that is glued onto a flexible Polyimide film, using flexible printed circuit production technology. Approximately 500 quench heaters with a total length of about 3000 m are needed for the HL-LHC magnets. In order to keep the heater circuit electrical resistance in acceptable limits, an approximately 10 µm-thick Cu coating is applied onto the steel foil. The quality of this Cu coating has been found critical in the quench heater production. The work described in this thesis focuses on the characterisation of Cu coatings produced by electrolytic deposition, sputtering and electron beam evaporation. The quality of the Cu coatings from different manufacturers has been assessed for instance by ambient temperature electrical res...

  9. Effect of inter-critical quenching on mechanical properties of casting low-alloy steel

    Directory of Open Access Journals (Sweden)

    Liu Zhongli

    2013-07-01

    Full Text Available For some casting low-alloy steels, traditional quenching and tempering heat treatments can improve the strength; however, sometimes the ductility is not satisfied. Therefore, some kind of effective heat treatment method seems necessary; one which could improve the ductility, but not seriously affect the strength. In this paper, the effect of inter-critical quenching (IQ on the mechanical properties of casting low-alloy steel was studied. IQ was added between quenching and tempering heat treatment; and the microstructure and mechanical properties were compared to the same steel with the traditional quenching and tempering treatments. The experimental results show that the microstructure comprises small-size ferrite and martensite when the IQ is adopted; and that different temperatures can control the ferrite quantity and distribution, and, as a result, influence the mechanical properties. In the case of IQ, the tensile strength decreases just a little, but the ductility increases a lot; and the strength-ductility product (its value is the arithmetic product of elongation and tensile strength increases by between 6% and 10%, which means the IQ heat treatment can improve comprehensive mechanical properties.

  10. Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from Radio Frequency plasma) experiment: tests in BATMAN (BAvarian Test Machine for Negative ions).

    Science.gov (United States)

    Brombin, M; Spolaore, M; Serianni, G; Pomaro, N; Taliercio, C; Dalla Palma, M; Pasqualotto, R; Schiesko, L

    2014-11-01

    A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors' holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

  11. Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

    Energy Technology Data Exchange (ETDEWEB)

    Brombin, M., E-mail: matteo.brombin@igi.cnr.it; Spolaore, M.; Serianni, G.; Pomaro, N.; Taliercio, C.; Palma, M. Dalla; Pasqualotto, R. [Consorzio RFX, Corso Stati Uniti 4, I-35127 Padova (Italy); Schiesko, L. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany)

    2014-11-15

    A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors’ holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

  12. Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

    Science.gov (United States)

    Brombin, M.; Spolaore, M.; Serianni, G.; Pomaro, N.; Taliercio, C.; Palma, M. Dalla; Pasqualotto, R.; Schiesko, L.

    2014-11-01

    A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors' holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

  13. Production of electron cyclotron resonance plasma by using multifrequencies microwaves and active beam profile control on a large bore electron cyclotron resonance ion source with permanent magnets.

    Science.gov (United States)

    Kato, Yushi; Watanabe, Takeyoshi; Matsui, Yuuki; Hirai, Yoshiaki; Kutsumi, Osamu; Sakamoto, Naoki; Sato, Fuminobu; Iida, Toshiyuki

    2010-02-01

    A new concept on magnetic field with all magnets on plasma production and confinement has been proposed to enhance efficiency of an electron cyclotron resonance (ECR) plasma for broad and dense ion beam source under the low pressure. The magnetic field configuration is constructed by a pair of magnets assembly, i.e., comb-shaped magnet which cylindrically surrounds the plasma chamber. The resonance zones corresponding to the fundamental ECR for 2.45 GHz and 11-13 GHz frequencies are constructed at different positions. The profiles of the plasma parameters in the ECR ion source are different from each frequency of microwave. Large bore extractor is set at the opposite side against the microwave feeds. It is found that differences of their profiles also appear at those of ion beam profiles. We conducted to launch simultaneously multiplex frequencies microwaves controlled individually, and tried to control the profiles of the plasma parameters and then those of extracted ion beam.

  14. Subsequent effect of subacute T-2 toxicosis on spermatozoa, seminal plasma and testosterone production in rabbits.

    Science.gov (United States)

    Kovács, M; Tornyos, G; Matics, Zs; Kametler, L; Rajli, V; Bodnár, Zs; Kulcsár, M; Huszenicza, Gy; Keresztes, Zs; Cseh, S

    2011-08-01

    Pannon White (n=12) male rabbits (weight: 4050 to 4500 g, age: 9 months) received 2 ml of a suspension containing purified T-2 toxin by gavage for 3 days. The daily toxin intake was 4 mg/animal (0.78 to 0.99 mg/kg body weight (BW)). Control animals (n=12) received toxin-free suspension for 3 days. Since a feed-refusal effect was observed on the second day after T-2 administration, a group of bucks (n=10) were kept as controls (no toxin treatment) but on a restricted feeding schedule, that is, the same amount of feed was provided to them as was consumed by the exposed animals. On day 51 of the experiment (i.e. 48 days after the 3-day toxin treatment), semen was collected, and pH, concentration, motility and morphology of the spermatozoa, as well as concentration of citric acid, zinc and fructose in the seminal plasma, were measured. After gonadotropin-releasing hormone (GnRH) analogue treatment, the testosterone level was examined. One day of T-2 toxin treatment dramatically decreased voluntary feed intake (by 27% compared to control, P0.05). The ratio of spermatozoa with abnormal morphology increased (Pplasma (Pplasma parameters (fructose and zinc) was observed. T-2 toxin decreased the basic testosterone level by 45% compared to control (Pcomposition of the seminal plasma or testosterone concentration--its effect needs further examination.

  15. RF Plasma Torch System for Metal Matrix Composite Production in Nuclear Fuel Cladding

    Science.gov (United States)

    Holik, Eddie, III

    2007-10-01

    For the first time in 30 years, plans are afoot to build new fission power plants in the US. It is timely to develop technology that could improve the safety and efficiency of new reactors. A program of development for advanced fuel cycles and Generation IV reactors is underway. The path to greater efficiency is to increase the core operating temperature. That places particular challenges to the cladding tubes that contain the fission fuel. A promising material for this purpose is a metal matrix composite (MMC) in which ceramic fibers are bonded within a high-strength steel matrix, much like fiberglass. Current MMC technology lacks the ability to effectively bond traditional high-temperature alloys to ceramic strands. The purpose of this project is to design an rf plasma torch system to use titanium as a buffer between the ceramic fibers and the refractory outer material. The design and methods of using an rf plasma torch to produce a non-equilibrium phase reaction to bond together the MMC will be discussed. The effects of having a long lived fuel cladding in the design of future reactors will also be discussed.

  16. Plasma processing of niobium for the production of thin-film superconducting devices

    Energy Technology Data Exchange (ETDEWEB)

    Tugwell, A.J.; Hutson, D.; Pegrum, C.M.; Donaldson, G.B.

    1987-01-01

    Josephson junctions, which are regions of weak electrical connection between two superconductors, are the active elements of very sensitive thin-film magnetometers. Junctions are fabricated by growing barriers of native oxide on thin Nb films and depositing a layer of PbIn alloy on top. High sensitivity magnetometers require junctions of small area, and to achieve this, edge junctions are fabricated in which one dimension is defined by the thickness of the Nb and the other is set by the limit of optical lithography. An edge with a suitable angle is produced by reactive ion etching using 5 vol % O/sub 2/ in CF/sub 4/ in a parallel plate rf plasma etcher. Details of etch rates and edge profiles are given. The barrier is formed by a cleaning and oxidation process in an rf plasma at a pressure of 10/sup -6/ bar. Details of the design of a purpose built rf cathode and the run-to-run reproducibility of junction characteristics are given. Different oxidation times and bias voltages are necessary to produce a given oxide thickness on a sloping edge of Nb, as compared to a planar surface, and an explanation for this is proposed. Examples are described of magnetometers made using the above processes.

  17. Production of geopolymers using glass produced from DC plasma treatment of air pollution control (APC) residues.

    Science.gov (United States)

    Kourti, Ioanna; Rani, D Amutha; Deegan, D; Boccaccini, A R; Cheeseman, C R

    2010-04-15

    Air pollution control (APC) residues are the hazardous waste produced from cleaning gaseous emissions at energy-from-waste (EfW) facilities processing municipal solid waste (MSW). APC residues have been blended with glass-forming additives and treated using DC plasma technology to produce a high calcium alumino-silicate glass. This research has investigated the optimisation and properties of geopolymers prepared from this glass. Work has shown that high strength geopolymers can be formed and that the NaOH concentration of the activating solution significantly affects the properties. The broad particle size distribution of the APC residue glass used in these experiments results in a microstructure that contains unreacted glass particles included within a geopolymer binder phase. The high calcium content of APC residues may cause the formation of some amorphous calcium silicate hydrate (C-S-H) gel. A mix prepared with S/L=3.4, Si/Al=2.6 and [NaOH]=6M in the activating solution, produced high strength geopolymers with compressive strengths of approximately 130 MPa. This material had high density (2070 kg/m(3)) and low porosity. The research demonstrates for the first time that glass derived from DC plasma treatment of APC residues can be used to form high strength geopolymer-glass composites that have potential for use in a range of applications.

  18. Optimization of plasma parameters for the production of silicon nano-crystals

    CERN Document Server

    Chaabane, N; Vach, H; Cabarrocas, P R I

    2003-01-01

    We use silane-hydrogen plasmas to synthesize silicon nano-crystals in the gas phase and thermophoresis to collect them onto a cooled substrate. To distinguish between nano-crystals formed in the plasma and those grown on the substrate, as a result of surface and subsurface reactions, we have simultaneously deposited films on a conventional substrate heated at 250 deg. C and on a second substrate cooled down to 90 deg. C. A series of samples deposited at various discharge pressures, in the range of 400 mTorr to 1.2 Torr, have been characterized by Raman spectroscopy and ellipsometry. At low pressure (400-500 mTorr), the films are amorphous on the cold substrate and micro-crystalline on the hot one. As pressure increases, gas phase reactions lead to the formation of nano-crystalline particles which are attracted by the cold substrate due to thermophoresis. Consequently, we obtain nano-crystalline silicon thin films on the cold substrate and amorphous thin films on the heated one in the pressure range of 600-900...

  19. Argon/UF6 plasma experiments: UF6 regeneration and product analysis

    Science.gov (United States)

    Roman, W. C.

    1980-03-01

    An experimental and analytical investigation was conducted to aid in developing some of the technology necessary for designing a self-critical fissioning uranium plasma core reactors (PCR). This technology is applicable to gaseous uranium hexafluoride nuclear-pumped laser systems. The principal equipment used included 1.2 MW RF induction heater, a d.c. plasma torch, a uranium tetrafluoride feeder system, and batch-type fluorine/UF6 regeneration systems. Overall objectives were to continue to develop and test materials and handling techniques suitable for use with high-temperature, high-pressure, gaseous UF6; and to continue development of complementary diagnostic instrumentation and measurement techniques to characterize the effluent exhaust gases and residue deposited on the test chamber and exhaust system components. Specific objectives include: a development of a batch-type UF6 regeneration system employing pure high-temperature fluorine; development of a ruggedized time-of-flight mass spectrometer and associated data acquisition system capable of making on-line concentration measurements of the volatile effluent exhaust gas species in a high RF environment and corrosive environment of UF6 and related halide compounds.

  20. Quenching of porous silicon photoluminescence by deposition of metal adsorbates

    Energy Technology Data Exchange (ETDEWEB)

    Andsager, D.; Hilliard, J.; Hetrick, J.M.; AbuHassan, L.H.; Plisch, M.; Nayfeh, M.H. (Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States))

    1993-10-01

    Various metals were deposited on luminescent porous silicon (PS) by immersion in metal ion solutions and by evaporation. The photoluminescence (PL) was quenched upon immersion in ionic solutions of Cu, Ag, and Au but not noticeably quenched in other ionic solutions. Evaporation of 100 A of Cu or 110 A of Au was not observed to quench PL. Auger electron spectroscopy performed on samples quenched and then immediately removed from solution showed a metallic concentration in the PS layer of order 10 at.%, but persisting to a depth of order 3000 A.

  1. Luminescence Decay Times and Bimolecular Quenching: An Ultrafast Kinetics Experiment

    Science.gov (United States)

    Demas, J. N.

    1976-01-01

    Describes the theory, apparatus, and procedure for an experiment that measures the bimolecular quenching constant for the deactivation of an excited ruthenium ion complex using dissolved oxygen. (MLH)

  2. Quench Analysis of the PANDA Target Spectrometer Solenoid

    CERN Document Server

    Deelen, Nikkie

    2014-01-01

    A quench analysis of the PANDA Target Solenoid has been performed. The characteristic time of the fast discharge is $12\\ \\text{s}$. The peak temperature and peak voltage during a quench are $30\\ \\text{K}$ and $160\\ \\text{V}$ respectively. During a quench the energy stored in the magnetic field is mostly dissipated in the dump resistor. The slow discharge of the PANDA solenoid takes approximately $1950\\ \\text{s}$ during which nearly all the energy is dissipated in the diodes of the quench protection circuit.

  3. Quenching of fluorescence in membrane protein by hypocrellin B.

    Science.gov (United States)

    Yue, J; Pang, S

    1997-04-01

    The hypocrellin B (HB) was used as a fluorescence quencher to study the basic physical charactcristics of HB in membrane systems, including the diffusion speed of quencher from aqueous phase into membrane phase, the partition coefficient (P) of quenchtr between membrane and water, and the fluorescence quenching constant of protein (K(sv); K(q),). The experimental results show that the quenching of fluorescence in membrane protein by HB can be determined by the principle of dynamic quenching. The experimental process of fluorescence quenching was observed in detail by using the ESR technique. The signal of HB- was found to arise from an electron transfer from excited trytophan to HB.

  4. Quenching of fluorescence in membrane protein by hypocrellin B

    Institute of Scientific and Technical Information of China (English)

    乐加昌; 庞素珍

    1997-01-01

    The hypocrellin B (HB) was used as a fluorescence quencher to study the basic physical characteris-tics of HB in membrane systems, including the diffusion speed of quencher from aqueous phase into membrane phase, the partition coefficient (P) of quencher between membrane and water, and the fluorescence quenching constant of protein (Ksv; Kq). The experimental results show that the quenching of fluorescence in membrane protein by HB can be determined by the principle of dynamic quenching. The experimental process of fluorescence quenching was ob-served in detail by using the ESR technique. The signal of HB" was found to arise from an electron transfer from ex-cited trytophan to HB.

  5. Optimising Gas Quenching Technology through Modelling of Heat Transfer

    Institute of Scientific and Technical Information of China (English)

    Florent Chaffotte; Linda L(e)fevre; Didier Domergue; Aymeric Goldsteinas; Xavier Doussot; Qingfei Zhang

    2004-01-01

    Gas Quenching represents an environmentally friendly alternative to more commonly-used oil quenching. Yet,the performances of this technology remain limited in terms of cooling rates reached compared to oil quenching. Distortion and process homogeneity also have to be controlled carefully. The efficiency of the gas quenching process fully depends on the heat transfer between the gas and the quenched parts. The goal of this study is the optimisation of the gas quenching process efficiency through a better understanding of the heat transfer phenomena involved. The study has been performed with modelling means and validated by an experimental approach. The configuration of the gas flow has a major influence on the heat transfer phenomena between the gas and the parts. The fluid dynamics modelling approach performed in this study allows to optimise the heat transfer phenomena. New gas quenching processes allowing enhanced gas quenching performance through higher cooling rates can be thereby identified. The new solutions have been validated in experimental and industrial conditions. Results obtained allow to expect significant improvement of high pressure gas quenching technology.

  6. Numerical Simulation on Carburizing and Quenching of Gear Ring

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The carburizing process of the gear ring was simulated by taking into account the practical carburizing and quenching techniques of the gear ring and by solving the diffusion equation. The carbon content distribution in the carburized layer was obtained. Based on the results, the quenching process of the gear ring was then simulated using the metallic thermodynamics and FEM; it was found that the carburization remarkably affects the quenching process.Microstructures and stress distributions of the gear ring in the quenching process were simulated, and the results are confirmed by experiments.

  7. Optimising Gas Quenching Technology through Modelling of Heat Transfer

    Institute of Scientific and Technical Information of China (English)

    FiorentChaffotte; LindaLefevre; DidierDomergue; AymericGoidsteinas; XavierDoussot; QingfeiZhang

    2004-01-01

    Gas Quenching represents an environmentally friendly alternative to more commonly-used oil quenching. Yet,the performances of this technology remain limited in terms of cooling rates reached compared to oil quenching. Distortion and process homogeneity also have to be controlled carefully. The efficiency of the gas quenching process fully depends on the heat transfer between the gas and the quenched parts. The goal of this study is the optimisation of the gas quenching process efficiency through a better understanding of the heat transfer phenomena involved. The study has been performed with modelling means and validated by an experimental approach. ThE configuration of the gas flow has a major influence on the heat transfer phenomena between the gas and the parts. The fluid dynamics modelling approach performed in this study allows to optimise the heat transfer phenomena. New gas quenching processes allowing enhanced gas quenching performance through higher cooling rates can be thereby identified. The new solutions have been validated in experimental and industrial conditions. Results obtained allow to expect significant improvement of high pressure gas quenching technology.

  8. Efficiency Assessment of Using Flammable Compounds from Water Treatment and Methanol Production Waste for Plasma Synthesis of Iron-Containing Pigments

    OpenAIRE

    Shekhovtsova, Anastasia; Karengin, Aleksander Grigorievich

    2016-01-01

    This article describes the possibility of applying the low-temperature plasma for obtaining iron-containing pigments from water purification and flammable methanol production waste. In this paper were calculated combustion parameters of water-saltorganic compositions (WSOC) with different consists. Authors determined the modes of energy- efficient processing of the previously mentioned waste in an air plasma. Having considered the obtained results there were carried out experiments with flamm...

  9. Efficiency Assessment of Using Flammable Compounds from Water Treatment and Methanol Production Waste for Plasma Synthesis of Iron-Containing Pigments

    Science.gov (United States)

    Shekhovtsova, Anastasia P.; Karengin, Alexander G.

    2016-08-01

    This article describes the possibility of applying the low-temperature plasma for obtaining iron-containing pigments from water purification and flammable methanol production waste. In this paper were calculated combustion parameters of water-saltorganic compositions (WSOC) with different consists. Authors determined the modes of energy- efficient processing of the previously mentioned waste in an air plasma. Having considered the obtained results there were carried out experiments with flammable dispersed water-saltorganic compositions on laboratory plasma stand. All the experimental results are confirmed by calculations.

  10. Hydrogen production from banyan leaves using an atmospheric-pressure microwave plasma reactor.

    Science.gov (United States)

    Lin, Yuan-Chung; Wu, Tzi-Yi; Jhang, Syu-Ruei; Yang, Po-Ming; Hsiao, Yi-Hsing

    2014-06-01

    Growth of the hydrogen market has motivated increased study of hydrogen production. Understanding how biomass is converted to hydrogen gas can help in evaluating opportunities for reducing the environmental impact of petroleum-based fuels. The microwave power used in the reaction is found to be proportional to the rate of production of hydrogen gas, mass of hydrogen gas produced per gram of banyan leaves consumed, and amount of hydrogen gas formed with respect to the H-atom content of banyan leaves decomposed. Increase the microwave power levels results in an increase of H2 and decrease of CO2 concentrations in the gaseous products. This finding may possibly be ascribed to the water-gas shift reaction. These results will help to expand our knowledge concerning banyan leaves and hydrogen yield on the basis of microwave-assisted pyrolysis, which will improve the design of hydrogen production technologies.

  11. Experimental methods for quenching structures in lunar-analog silicate melts: Variations as a function of quench media and composition

    Science.gov (United States)

    Dyar, M. D.

    1985-01-01

    Compositions analogous to lunar green, organge, and brown glasses were synthesized under consistent conditions, then quenched into a variety of different media when the samples were removed from the furnace. Iron valence and coordination are a direct function of quench media used, spanning the range from brine/ice (most effective quench), water, butyl phthalate, silicone oil, liquid nitrogen, highly reducing CO-CO2 gas, to air (least efficient quench). In the green and brown glasses, Fe(3+) in four-fold and six-fold coordination is observed in the slowest-quenched samples; Fe(2+) coordination varies directly with quench efficiency. Less pronounced changes were observed in the Ti-rich orange glass. Therefore the remote-sensed spectrum of a glass-bearing regolith on the Moon may be influenced by the process by which the glass cooled, and extreme caution must be used when comparing spectra of synthetic glass analogs with real lunar glasses.

  12. Experimental methods for quenching structures in lunar-analog silicate melts - Variations as a function of quench media and composition

    Science.gov (United States)

    Dyar, M. D.

    1984-01-01

    Compositions analogous to lunar green, orange, and brown glasses were synthesized under consistent conditions, then quenched into a variety of different media when the samples were removed from the furnace. Iron valence and coordination are a direct function of quench media used, spanning the range from brine/ice (most effective quench), water, butyl phthalate, silicone oil, liquid nitrogen, highly reducing CO-CO2 gas, to air (least efficient quench). In the green and brown glasses, Fe(3+) in four-fold and six-fold coordination is observed in the slowest-quenched samples; Fe(2+) coordination varies directly with quench efficiency. Less pronounced changes were observed in the Ti-rich orange glass. Therefore the remote-sensed spectrum of a glass-bearing regolith on the moon may be influenced by the process by which the glass cooled, and extreme caution must be used when comparing spectra of synthetic glass analogs with real lunar glasses.

  13. Effect of rooibos tea (Aspalathus linearis) on Japanese quail growth, egg production and plasma metabolites.

    Science.gov (United States)

    Juráni, M; Lamosová, D; Mácajová, M; Kostál, L; Joubert, E; Greksák, M

    2008-01-01

    1. Birds have been proposed as a suitable model for studies on ageing because of their long life in comparison with similar-sized mammals. However, some weak fliers, such as Galliformes, are the exception to this rule. The aim of the present study was to determine the effects of the treatment with rooibos tea (Aspalathus linearis), a natural source of flavonoid antioxidants and compounds with phyto-oestrogenic activity, on postnatal development and egg production of aged Japanese quail (Coturnix coturnix japonica). 2. Substitution of drinking water with traditional rooibos tea or diet supplementation with ground rooibos tea affected body weight of Japanese quail up to 100 d of age. The body weight of males drinking rooibos tea or eating rooibos-supplemented food decreased significantly. There was a trend toward increased body weight of tea drinking females and a significant increase in the body weight of hens fed the rooibos-supplemented diet. Although rooibos treatment did not significantly increase egg production in young hens, the decrease in egg production of rooibos-treated aged hens (360 d of age) was significantly reduced, regardless of the egg production levels (high - 80%; low - 20%) before the treatment. 3. The results suggest that treatment with rooibos tea positively affected body weight and egg production in quail hens and prolonged the productive period of aged animals. Further studies would be needed to address the question whether these effects are due to the antioxidant or phyto-oestrogenic activities of rooibos.

  14. Plasma membrane is the site of productive HIV-1 particle assembly.

    Directory of Open Access Journals (Sweden)

    Nolwenn Jouvenet

    2006-12-01

    Full Text Available Recently proposed models that have gained wide acceptance posit that HIV-1 virion morphogenesis is initiated by targeting the major structural protein (Gag to late endosomal membranes. Thereafter, late endosome-based secretory pathways are thought to deliver Gag or assembled virions to the plasma membrane (PM and extracellular milieu. We present several findings that are inconsistent with this model. Specifically, we demonstrate that HIV-1 Gag is delivered to the PM, and virions are efficiently released into the extracellular medium, when late endosome motility is abolished. Furthermore, we show that HIV-1 virions are efficiently released when assembly is rationally targeted to the PM, but not when targeted to late endosomes. Recently synthesized Gag first accumulates and assembles at the PM, but a proportion is subsequently internalized via endocytosis or phagocytosis, thus accounting for observations of endosomal localization. We conclude that HIV-1 assembly is initiated and completed at the PM, and not at endosomal membranes.

  15. Production of Cloned Miniature Pigs Expressing High Levels of Human Apolipoprotein(a in Plasma.

    Directory of Open Access Journals (Sweden)

    Masayuki Ozawa

    Full Text Available High lipoprotein(a [Lp(a] levels are a major risk factor for the development of atherosclerosis. However, because apolipoprotein(a [apo(a], the unique component of Lp(a, is found only in primates and humans, the study of human Lp(a has been hampered due to the lack of appropriate animal models. Using somatic cell nuclear transfer (SCNT techniques, we produced transgenic miniature pigs expressing human apo(a in the plasma. First, we placed the hemagglutinin (HA-tagged cDNA of human apo(a under the control of the β-actin promoter and cytomegalovirus enhancer, and then introduced this construct into kidney epithelial cells. Immunostaining of cells with anti-HA antibody allowed identification of cells stably expressing apo(a; one of the positive clones was used to provide donor cells for SCNT, yielding blastocysts that expressed apo(a. Immunohistochemical analysis of tissue sections and RT-PCR analysis of total RNA from organs of cloned piglet revealed that apo(a is expressed in various tissues/organs including heart, liver, kidney, and intestine. More importantly, a transgenic line exhibited a high level (>400 mg/dL of Lp(a in plasma, and the transgenic apo(a gene was transmitted to the offspring. Thus, we generated a human apo(a-transgenic miniature pig that can be used as a model system to study advanced atherosclerosis related to human disease. The anatomical and physiological similarities between the swine and human cardiovascular systems will make this pig model a valuable source of information on the role of apo(a in the formation of atherosclerosis, as well as the mechanisms underlying vascular health and disease.

  16. Dynamic scaling at classical phase transitions approached through nonequilibrium quenching

    Science.gov (United States)

    Liu, Cheng-Wei; Polkovnikov, Anatoli; Sandvik, Anders W.

    2014-02-01

    We use Monte Carlo simulations to demonstrate generic scaling aspects of classical phase transitions approached through a quench (or annealing) protocol where the temperature changes as a function of time with velocity v. Using a generalized Kibble-Zurek ansatz, we demonstrate dynamic scaling for different types of stochastic dynamics (Metropolis, Swendsen-Wang, and Wolff) on Ising models in two and higher dimensions. We show that there are dual scaling functions governing the dynamic scaling, which together describe the scaling behavior in the entire velocity range v ∈[0,∞). These functions have asymptotics corresponding to the adiabatic and diabatic limits, and close to these limits they are perturbative in v and 1/v, respectively. Away from their perturbative domains, both functions cross over into the same universal power-law scaling form governed by the static and dynamic critical exponents (as well as an exponent characterizing the quench protocol). As a by-product of the scaling studies, we obtain high-precision estimates of the dynamic exponent z for the two-dimensional Ising model subject to the three variants of Monte Carlo dynamics: for single-spin Metropolis updates zM=2.1767(5), for Swendsen-Wang multicluster updates zSW=0.297(3), and for Wolff single-cluster updates zW=0.30(2). For Wolff dynamics, we find an interesting behavior with a nonanalytic breakdown of the quasiadiabatic and diabatic scalings, instead of the generic smooth crossover described by a power law. We interpret this disconnect between the two scaling regimes as a dynamic phase transition of the Wolff algorithm, caused by an effective sudden loss of ergodicity at high velocity.

  17. A perturbative framework for jet quenching

    CERN Document Server

    Zapp, Korinna C; Wiedemann, Urs A

    2013-01-01

    We present a conceptually new framework for describing jet evolution in the dense medium produced in ultra-relativistic nucleus-nucleus collisions using perturbative QCD and its implementation into the Monte Carlo event generator JEWEL. The rescattering of hard partons in the medium is modelled by infrared continued pQCD matrix elements supplemented with parton showers. The latter approximate higher order real-emission matrix elements and thus generate medium-induced gluon emissions. The interplay between different emissions is governed by their formation times. The destructive interference between subsequent scattering processes, the non-Abelian version of the Landau-Pomeranchuk-Migdal effect, is also taken into account. In this way the complete radiation pattern is consistently treated in a uniform way. Results obtained within this minimal and theoretically well constrained framework are compared with a variety of experimental data susceptible to jet-quenching effects at both RHIC and the LHC. Overall, a go...

  18. Response functions after a quantum quench

    Science.gov (United States)

    Marcuzzi, Matteo; Gambassi, Andrea

    2014-04-01

    The response of physical systems to external perturbations can be used to probe both their equilibrium and nonequilibrium dynamics. While response and correlation functions are related in equilibrium by fluctuation-dissipation theorems, out of equilibrium they provide complementary information on the dynamics. In the past years, a method has been devised to map the quantum dynamics of an isolated extended system after a quench onto a static theory with boundaries in imaginary time; up to now, however, the focus was entirely on symmetrized correlation functions. Here we provide a prescription which, in principle, allows one to retrieve the whole set of relevant dynamical quantities characterizing the evolution, including linear response functions. We illustrate this construction with some relevant examples, showing in the process the emergence of light-cone effects similar to those observed in correlation functions.

  19. How Cosmic Web Detachment Drives Galaxy Quenching

    CERN Document Server

    Aragon-Calvo, Miguel A; Silk, Joseph

    2016-01-01

    We present the Cosmic Web Detachment (CWD) model, a conceptual framework to interpret galaxy evolution in a cosmological context, providing a direct link between the star formation history of galaxies and the cosmic web. The CWD model unifies several mechanism known to disrupt or stop star formation into one single physical process and provides a natural explanation for a wide range of galaxy properties. Galaxies begin accreting star-forming gas at early times via a network of primordial highly coherent filaments. The efficient star formation phase ends when non-linear interactions with other galaxies or elements of the cosmic web detach the galaxy from its network of primordial filaments, thus ending the efficient accretion of cold gas. The stripping of the filamentary web around galaxies is the physical process responsible of star formation quenching in gas stripping, harassment, strangulation and starvation. Being a purely gravitational/mechanical process CWD acts at a more fundamental level than internal ...

  20. Thermal quenching of luminescence processes in feldspars

    DEFF Research Database (Denmark)

    Poolton, N.R.J.; Bøtter-Jensen, L.; Duller, G.A.T.

    1995-01-01

    The technique of optically stimulated luminescence has important uses in the dose evaluation of irradiated feldspars. The luminescence process involves the eviction of electrons from donor traps, charge transfer through the conduction band, and recombination at acceptor sites; each...... of these processes is, in general, thermally dependent, and leads either to enhancement or quenching of the luminescence with increasing temperature. Previous studies have measured the combined thermal activation characteristics of all three processes, and show a strong dependence on stimulation energy....... In this article, an initial attempt is made to isolate only the recombination part of the luminescence cycle, and determine its thermal characteristics separately. A Variety of luminescence transitions are examined in a range of both alkali and plagioclase feldspars; three distinct emission types are identified...

  1. Charmonium properties in hot quenched lattice QCD

    CERN Document Server

    Ding, H -T; Kaczmarek, O; Karsch, F; Satz, H; Soeldner, W

    2012-01-01

    We study the properties of charmonium states at finite temperature in quenched QCD on large and fine isotropic lattices. We perform a detailed analysis of charmonium correlation and spectral functions both below and above $T_c$. Our analysis suggests that both S wave states ($J/\\psi$ and $\\eta_c$) and P wave states ($\\chi_{c0}$ and $\\chi_{c1}$) disappear already at about $1.5 T_c$. The charm diffusion coefficient is estimated through the Kubo formula and found to be compatible with zero below $T_c$ and approximately $1/\\pi T$ at $1.5 T_c\\lesssim T\\lesssim 3 T_c$.

  2. Charmonium properties in hot quenched lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Ding, H. -T.; Francis, A.; Kaczmarek, O.; Karsch, F.; Satz, H.; Soeldner, W.

    2012-07-01

    We study the properties of charmonium states at finite temperature in quenched QCD on large and fine isotropic lattices. We perform a detailed analysis of charmonium correlation and spectral functions both below and above Tc. Our analysis suggests that both S wave states (J/ψ and ηc) and P wave states (χc0 and χc1) disappear already at about 1.5Tc. The charm diffusion coefficient is estimated through the Kubo formula and found to be compatible with zero below Tc and approximately 1/πT at 1.5Tc≲T≲3Tc.

  3. Magnetic Barkhausen Noise in quenched carburized steels

    Energy Technology Data Exchange (ETDEWEB)

    De Campos, M F; Santos, R; Da Silva, F S; Lins, J F C [PUVR- Universidade Federal Fluminense, Av dos Trabalhadores 420, Vila Santa Cecilia, Volta Redonda, RJ, 27255-125 (Brazil); Franco, F A; Ribeiro, S B; Padovese, L R, E-mail: mcampos@metal.eeimvr.uff.br, E-mail: mfdcampo@uol.com.br [Escola Politecnica, Universidade de Sao Paulo, Sao Paulo, SP (Brazil)

    2011-07-06

    Steels with different carbon content, 0.11%C and 0.48%C were submitted to a heat treatment for carburization in the surface. The samples were analyzed after several types of heat treatment, including quenching for producing martensite. The Magnetic Barkhausen Noise (MBN) is directly related to the microstructure. Samples with lower carbon content, have ferrite, a constituent where domain walls can move freely and present higher amplitude in the envelope of MBN. It is also found that the MBN peaks are quite distinct for the samples with martensite, which have lower permeability, and the results suggest that domain rotation contributes as mechanism for reversal of magnetization in martensite. The results also indicate that MBN is very suitable for monitoring the carburizing heat treatment.

  4. Magnetic Barkhausen Noise in quenched carburized steels

    Science.gov (United States)

    de Campos, M. F.; Franco, F. A.; Santos, R.; da Silva, F. S.; Ribeiro, S. B.; Lins, J. F. C.; Padovese, L. R.

    2011-07-01

    Steels with different carbon content, 0.11%C and 0.48%C were submitted to a heat treatment for carburization in the surface. The samples were analyzed after several types of heat treatment, including quenching for producing martensite. The Magnetic Barkhausen Noise (MBN) is directly related to the microstructure. Samples with lower carbon content, have ferrite, a constituent where domain walls can move freely and present higher amplitude in the envelope of MBN. It is also found that the MBN peaks are quite distinct for the samples with martensite, which have lower permeability, and the results suggest that domain rotation contributes as mechanism for reversal of magnetization in martensite. The results also indicate that MBN is very suitable for monitoring the carburizing heat treatment.

  5. Collisional quenching of highly rotationally excited HF

    CERN Document Server

    Yang, Benhui; Forrey, R C; Stancil, P C; Balakrishnan, N

    2015-01-01

    Collisional excitation rate coefficients play an important role in the dynamics of energy transfer in the interstellar medium. In particular, accurate rotational excitation rates are needed to interpret microwave and infrared observations of the interstellar gas for nonlocal thermodynamic equilibrium line formation. Theoretical cross sections and rate coefficients for collisional deexcitation of rotationally excited HF in the vibrational ground state are reported. The quantum-mechanical close-coupling approach implemented in the nonreactive scattering code MOLSCAT was applied in the cross section and rate coefficient calculations on an accurate 2D HF-He potential energy surface. Estimates of rate coefficients for H and H$_2$ colliders were obtained from the HF-He collisional data with a reduced-potential scaling approach. The calculation of state-to-state rotational quenching cross sections for HF due to He with initial rotational levels up to $j=20$ were performed for kinetic energies from 10$^{-5}$ to 15000...

  6. Thermal quenching of fluorescence in condensed media

    Science.gov (United States)

    Lagos, Miguel; Paredes, Rodrigo

    2016-09-01

    Environmental factors strongly affect the features of the electromagnetic spectra of fluorescent compounds hosted by material media. The shape of the absorption and emission peaks, their characteristic asymmetry and breadth, the Stokes shift and quantum yield are generally temperature dependent and heavily influenced by both the local and extended physical properties of the medium. The theoretical method used before to obtain the lineshape function is extended here to other terms of the interaction energy between the optically sensitive orbital and the hosting medium, which become significant when the spectral feature is broad. An analytical expression for the temperature dependent decay rate by non-radiative processes is obtained by this way. Comparison with experiment on thermal quenching gives agreement within the experimental uncertainty. The solvent polarity, its protic or aprotic character, hydrogen bonds, proximity effects and presence of quenchers are expected to enter through the coupling constants of the corresponding energy terms.

  7. Orientifold Planar Equivalence: The Quenched Meson Spectrum

    CERN Document Server

    Lucini, Biagio; Patella, Agostino; Rago, Antonio

    2010-01-01

    A numerical study of Orientifold Planar Equivalence is performed in SU(N) Yang-Mills theories for N=2,3,4,6. Quenched meson masses are extracted in the antisymmetric, symmetric and adjoint representations for the pseudoscalar and vector channels. An extrapolation of the vector mass as a function of the pseudoscalar mass to the large-N limit shows that the numerical results agree within errors for the three theories, as predicted by Orientifold Planar Equivalence. As a byproduct of the extrapolation, the size of the corrections up to O(1/N^3) are evaluated. A crucial prerequisite for the extrapolation is the determination of an analytical relationship between the corrections in the symmetric and in the antisymmetric representations, order by order in a 1/N expansion.

  8. Quenched mesonic spectrum at large N

    CERN Document Server

    Del Debbio, Luigi; Patella, Agostino; Pica, Claudio

    2008-01-01

    We compute the masses of the $\\pi$ and of the $\\rho$ mesons in the quenched approximation on a lattice with fixed lattice spacing $a \\simeq 0.145 \\ \\mathrm{fm}$ for SU($N$) gauge theory with $N = 2,3,4,6$. We find that a simple linear expression in $1/N^2$ correctly captures the features of the lowest-lying meson states at those values of $N$. This enables us to extrapolate to $N = \\infty$ the behaviour of $m_{\\pi}$ as a function of the quark mass and of $m_{\\rho}$ as a function of $m_{\\pi}$. Our results for the latter agree within 5% with recent predictions obtained in the AdS/CFT framework.

  9. [Historical changes in the list of plasma fractionation products placed on the WHO Model List of Essential Medicines].

    Science.gov (United States)

    Sakagami, Yuichiro; Tsutani, Kiichiro

    2014-01-01

    The purpose of this study was to summarize the historical changes in the list of plasma fractionation products (PFP) placed on the Model List of Essential Medicines (EML) issued by the World Health Organization (WHO). PFP such as albumin, blood coagulation factors, and immunoglobulins are derived from blood collected from thousands of people. PFP have been listed since the first edition of the EML (1977). However, the PFP listed on the EML have changed dramatically because EML's selection process has changed from experience-based to evidence-based. For example, albumin, which had been listed since the 2nd edition (1979), was deleted in the 11th edition (2000) because of the uncertainty of its efficacy. Human immunoglobulin normal, which had been deleted from the 13th edition (2003), was relisted in the 15th edition (2007). Moreover, the WHO has issued several resolutions and guidelines regarding PFP production, quality, and safety in order to promote the establishment of blood programmes in every nation. The focus of WHO's EML selection process has changed over 30 years. In the 20th century, WHO mainly focused on PFP efficacy, quality, and safety problems. However, currently the focus is on the problem of PFP accessibility, especially in developing countries. Therefore, it would be important to know how to capitalize on established knowledge and production technology to increase the accessibility of PFP worldwide.

  10. On the impact of the plasma jet energy on the product of plasmadynamic synthesis in the Si-C system

    Science.gov (United States)

    Nikitin, D.; Sivkov, A.

    2015-10-01

    Silicon carbide (SiC) nanoparticles can be used for ceramics reinforcement, creation of nanostructured ceramics, microelectromechanical systems. The paper presents the results of plasmadynamic synthesis of silicon carbide nanopowders. This method was realized by the synthesis in an electrodischarge plasma jet generated by a high-current pulsed coaxial magnetoplasma accelerator. Powdered carbon and silicon were used as precursors for the reaction. Four experiments with different energy levels (from 10.0 to 30.0 kJ) were carried out. The synthesized products were analysed by several modern techniques including X-ray diffractometry, scanning and transmission electron microscopy. According to analysis results all the products mainly composed of cubic silicon carbide (b-SiC) with a small amount of unreacted precursors. Silicon carbide particles have a clear crystal structure, a triangular shape and sizes to a few hundred nanometers. Comparison of the results of experiments with different energy levels made it possible to draw conclusions on ways to control product phase composition and dispersion. The silicon carbide content and particles sizes increase with increasing the energy level.

  11. Rapid analysis of pharmaceuticals and personal care products in fish plasma micro-aliquots using liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Chen, Fangfang; Gong, Zhiyuan; Kelly, Barry C

    2015-02-27

    A sensitive analytical method based on liquid-liquid extraction (LLE) and liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed for rapid analysis of 11 pharmaceuticals and personal care products (PPCPs) in fish plasma micro-aliquots (∼20μL). Target PPCPs included, bisphenol A, carbamazepine, diclofenac, fluoxetine, gemfibrozil, ibuprofen, naproxen, risperidone, sertraline, simvastatin and triclosan. A relatively quicker and cheaper LLE procedure exhibited comparable analyte recoveries with solid-phase extraction. Rapid separation and analysis of target compounds in fish plasma extracts was achieved by employing a high efficiency C-18 HPLC column (Agilent Poroshell 120 SB-C18, 2.1mm×50mm, 2.7μm) and fast polarity switching, enabling effective monitoring of positive and negative ions in a single 9min run. With the exception of bisphenol A, which exhibited relatively high background contamination, method detection limits of individual PPCPs ranged between 0.15 and 0.69pg/μL, while method quantification limits were between 0.05 and 2.3pg/μL. Mean matrix effect (ME) values ranged between 65 and 156% for the various target analytes. Isotope dilution quantification using isotopically labelled internal surrogates was utilized to correct for signal suppression or enhancement and analyte losses during sample preparation. The method was evaluated by analysis of 20μL plasma micro-aliquots collected from zebrafish (Danio rerio) from a laboratory bioaccumulation study, which included control group fish (no exposure), as well as fish exposed to environmentally relevant concentrations of PPCPs. Using the developed LC-MS/MS based method, concentrations of the studied PPCPs were consistently detected in the low pg/μL (ppb) range. The method may be useful for investigations requiring fast, reliable concentration measurements of PPCPs in fish plasma. In particular, the method may be applicable for in situ contaminant biomonitoring, as well as

  12. Ion-cyclotron instability in plasmas described by product-bi-kappa distributions

    Energy Technology Data Exchange (ETDEWEB)

    Santos, M. S. dos; Ziebell, L. F., E-mail: luiz.ziebell@ufrgs.br; Gaelzer, R., E-mail: rudi.gaelzer@ufrgs.br [Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, CEP: 91501-970 Porto Alegre, RS (Brazil)

    2015-12-15

    The dispersion relation for parallel propagating waves in the ion-cyclotron branch is investigated numerically by considering that the velocity distribution of the ion population is a function of type product-bi-kappa. We investigate the effects of the non-thermal features and of the anisotropy associated with this type of distribution on the ion-cyclotron instability, as well as the influence of different forms of the electron distribution, by considering Maxwellian distributions, bi-kappa distributions, and product-bi-kappa distributions. The cases of ions described by either Maxwellian or bi-kappa distributions are also considered, for comparison. The results of the numerical analysis show that the increase in the non-thermal character associated with the anisotropic kappa distributions for ions contributes to enhance the instability as compared to that obtained in the Maxwellian case, in magnitude and in wave number range, with more significant enhancement for the case of ion product-bi-kappa distributions than for the case of ion bi-kappa distributions. It is also shown that the ion-cyclotron instability is decreased if the electrons are described by product-bi-kappa distributions, while electrons described by bi-kappa distributions lead to growth rates which are very similar to those obtained considering a Maxwellian distribution for the electron population.

  13. An Efficient Fluid-Dynamic Analysis to Improve Industrial Quenching Systems

    Directory of Open Access Journals (Sweden)

    Manuel de J. Barrena-Rodríguez

    2017-05-01

    Full Text Available This paper addresses the problem of understanding the relationship between fluid flow and heat transfer in industrial quenching systems. It also presents an efficient analysis to design or optimize long standing quenching tanks to increase productivity. The study case is automotive leaf springs quenched in an oil-tank agitated with submerged jets. This analysis combined an efficient numerical prediction of the detailed isothermal flow field in the whole tank with the thermal characterization of steel probes in plant and laboratory during quenching. These measurements were used to determine the heat flow by solving the inverse heat conduction problem. Differences between laboratory and plant heat flux results were attributed to the difference in surface area size between samples. A proposed correlation between isothermal wall shear stress and heat flux at the surface of the steel component, based on the Reynolds-Colburn analogy, provided the connection between thermal characterization and computed isothermal fluid flow. The present approach allowed the identification of the potential benefits of changes in the tank design and the evaluation of operating conditions while using a much shorter computing time and storage memory than full-domain fluid flow calculations.

  14. Bioluminophore and Flavin Mononucleotide Fluorescence Quenching of Bacterial Bioluminescence-A Theoretical Study.

    Science.gov (United States)

    Luo, Yanling; Liu, Ya-Jun

    2016-11-02

    Bacterial bioluminescence with continuous glow has been applied to the fields of environmental toxin monitoring, drug screening, and in vivo imaging. Nonetheless, the chemical form of the bacterial bioluminophore is still a bone of contention. Flavin mononucleotide (FMN), one of the light-emitting products, and 4a-hydroxy-5-hydro flavin mononucleotide (HFOH), an intermediate of the chemical reactions, have both been assumed candidates for the light emitter because they have similar molecular structures and fluorescence wavelengths. The latter is preferred in experiments and was assigned in our previous density functional study. HFOH displays weak fluorescence in solutions, but exhibits strong bioluminescence in the bacterial luciferase. FMN shows the opposite behavior; its fluorescence is quenched when it is bound to the luciferase. This is the first example of flavin fluorescence quenching observed in bioluminescent systems and is merely an observation, both the quenching mechanism and quencher are still unclear. Based on theoretical analysis of high-level quantum mechanics (QM), combined QM and molecular mechanics (QM/MM), and molecular dynamics (MD), this paper confirms that HFOH in its first singlet excited state is the bioluminophore of bacterial bioluminescence. More importantly, the computational results indicate that Tyr110 in the luciferase quenches the FMN fluorescence via an electron-transfer mechanism.

  15. Hadron production in relativistic heavy ion interactions and the search for the quark-gluon plasma

    Energy Technology Data Exchange (ETDEWEB)

    Tannenbaum, M.J.

    1989-12-01

    The course starts with an introduction, from the experimentalist's point of view, of the challenge of measuring Relativistic Heavy Ion interactions. A review of some theoretical predictions for the expected signatures of the quark gluon plasma will be made, with a purpose to understand how they relate to quantities which may be experimentally measured. A short exposition of experimental techniques and details is given including charged particles in matter, momentum resolution, kinematics and Lorentz Transformations, calorimetry. Principles of particle identification including magnetic spectrometers, time of flight measurement. Illustrations using the E802 spectrometer and other measured results. Resolution smearing of spectra, and binning effects. Parent to daughter effects in decay, with {pi}{sup 0} {yields} {gamma} {gamma} as an example. The experimental situation from the known data in p -- p collisions and proton-nucleus reactions is reviewed and used as a basis for further discussions. The Cronin Effect'' and the Seagull Effect'' being two arcana worth noting. Then, selected experiments from the BNL and CERN heavy ion programs are discussed in detail. 118 refs., 45 figs.

  16. Neutron production with mixture of deuterium and krypton in Sahand Filippov type plasma focus facility

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi, M.A., E-mail: mohammadidorbash@yahoo.com [Department of Atomic and Molecular Physics, Faculty of Physics, University of Tabriz, Tabriz (Iran, Islamic Republic of); Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz (Iran, Islamic Republic of); Sobhanian, S. [Department of Atomic and Molecular Physics, Faculty of Physics, University of Tabriz, Tabriz (Iran, Islamic Republic of); Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz (Iran, Islamic Republic of); Rawat, R.S. [Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University (Singapore)

    2011-08-01

    This Letter reports the order of magnitude enhancement in neutron yield from Sahand plasma focus device with krypton seeded deuterium operation. The highest average neutron yield of 2.2x10{sup 9} neutrons per shot was achieved at 1.00 Torr deuterium with 3% krypton which is higher than the best average neutron yield of 3.18x10{sup 8} neutrons per shot for pure deuterium operation. Estimation of average neutron energy showed that the maximum and minimum average energies are 2.98±0.6 MeV at 16 kV in 0.25 Torr deuterium with 3% Kr and 2.07±0.2 MeV at 18 kV operation in 0.5 Torr deuterium with 3% Kr, respectively. The anisotropy of neutron emission from Sahand DPF showed that the neutrons are produced mainly by beam-target mechanisms. -- Highlights: → The highest average neutron yield of 2.2x10{sup 9} neutrons per shot was achieved at mixture of deuterium and krypton. → In the krypton seeding of deuterium also anisotropy of neutron emission deuterium is found. → The krypton seeding of deuterium made the neutron emission more reliable over wider operating pressure ranges.

  17. Effect of dietary protein sources on production performance, egg quality, and plasma parameters of laying hens

    Science.gov (United States)

    Wang, Xiaocui; Zhang, Haijun; Wang, Hao; Wang, Jing; Wu, Shugeng; Qi, Guanghai

    2017-01-01

    Objective This study was conducted to evaluate the effects of dietary protein sources (soybean meal, SBM; low-gossypol cottonseed meal, LCSM; double-zero rapeseed meal, DRM) on laying performance, egg quality, and plasma parameters of laying hens. Methods A total of 432 32-wk-old laying hens were randomly divided into 6 treatments with 6 replicates of 12 birds each. The birds were fed diets containing SBM, LCSM100, or DRM100 individually or in combination with an equal amount of crude protein (CP) (LCSM50, DRM50, and LCSM50-DRM50). The experimental diets, which were isocaloric (metabolizable energy, 11.11 MJ/kg) and isonitrogenous (CP, 16.5%), had similar digestible amino acid profile. The feeding trial lasted 12 weeks. Results The daily egg mass was decreased in the LCSM100 and LCSM50-DRM50 groups (p0.05) and showed increased yolk color at the end of the trial (p0.05). Conclusion Together, our results suggest that the LCSM100 or DRM100 diets may produce the adverse effects on laying performance and egg quality after feeding for 8 more weeks. The 100.0 g/kg LCSM diet or the148.7 g/kg DRM diet has no adverse effects on laying performance and egg quality. PMID:27608634

  18. Silanization of plasma-grown silicon quantum dots for production of a tunable, stable, colloidal solution

    Science.gov (United States)

    Anderson, Ingrid E.; Shircliff, Rebecca A.; Lee, Benjamin G.; Simonds, Brian; Agarwal, Sumit; Stradins, Paul; Collins, Reuben T.

    2011-09-01

    Nanomaterials have the potential to revolutionize photovoltaics with the promise of new physics, novel architectures and low cost synthesis. Silicon quantum dots, relative to their II-VI counterparts, are understudied due to the difficulty of solution synthesis and chemical passivation. However, silicon is still an attractive solar cell material, providing an optimal band gap, low toxicity, and a very solid body of physical understanding of bulk silicon to draw from. We have synthesized silicon quantum dots with plasma enhanced chemical vapor deposition, and have developed a method for chemical passivation of these silicon quantum dots that can be used on particles created in a variety of ways. This versatile method utilizes oxidation via wet chemical etch and subsequent siloxane bond formation. The attachment of a silane to the SiOx shell leads to stability of the silicon core for over a month in air, and individual particles can be seen with TEM; thus a stable, colloidal suspension is formed. The future for this technique, including increasing quantum yield of the particles by changing the nature of the oxide, will be discussed.

  19. Analysis of Pregnancy-Associated Plasma Protein A Production in Human Adult Cardiac Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Piera D’Elia

    2013-01-01

    Full Text Available IGF-binding proteins (IGFBPs and their proteases regulate IGFs bioavailability in multiple tissues. Pregnancy-associated plasma protein A (PAPP-A is a protease acting by cleaving IGFBP2, 4, and 5, regulating local bioavailability of IGFs. We have previously shown that IGFs and IGFBPs are produced by human adult cardiac progenitor cells (haCPCs and that IGF-1 exerts paracrine therapeutic effects in cardiac cell therapy with CPCs. Using immunofluorescence and enzyme immunoassays, we firstly report that PAPP-A is produced and secreted in surprisingly high amounts by haCPCs. In particular, the homodimeric, enzymatically active, PAPP-A is secreted in relevant concentrations in haCPC-conditioned media, while the enzymatically inactive PAPPA/proMBP complex is not detectable in the same media. Furthermore, we show that both homodimeric PAPP-A and proMBP can be detected as cell associated, suggesting that the previously described complex formation at the cell surface does not occur easily, thus positively affecting IGF signalling. Therefore, our results strongly support the importance of PAPP-A for the IGFs/IGFBPs/PAPP-A axis in CPCs biology.

  20. Quark production, Bose-Einstein condensates and thermalization of the quark-gluon plasma

    CERN Document Server

    Blaizot, Jean-Paul; Yan, Li

    2014-01-01

    In this paper, we study the thermalization of gluons and N_f flavors of massless quarks and antiquarks in a spatially homogeneous system. First, two coupled transport equations for gluons and quarks (and antiquarks) are derived within the diffusion approximation of the Boltzmann equation, with only 2 2 processes included in the collision term. Then, these transport equations are solved numerically in order to study the thermalization of the quark-gluon plasma. At initial time, we assume that no quarks or antiquarks are present and we choose the gluon distribution in the form f = f_0 theta (1-p/Q_s) with Q_s the saturation momentum and f_0 a constant. The subsequent evolution of systems may, or may not, lead to the formation of a (transient) Bose condensate, depending on the value of f_0. In fact, we observe, depending on the value of f_0, three different patterns: (a) thermalization without gluon Bose-Einstein condensate (BEC) for f_0 1 > f_{0c}, the onset of BEC occurs at a finite time t_c ~ 1/((alpha_s f_0...

  1. Stability and quench development study in small HTSC magnet

    NARCIS (Netherlands)

    Ilyin, Yu. A.; Vysotski, V.S.; Kiss, T.; Takeo, M.; Okamoto, H.; Irie, F.

    2001-01-01

    Stability and quench development in a HTSC magnet have been experimentally studied with the transport current in the magnet being below or above the “thermal quench current” level. The magnet was tested at both cryocooler cooling and liquid nitrogen cooling, with and without background magnetic fiel

  2. The quenched generating functional for hadronic weak interactions

    NARCIS (Netherlands)

    Pallante, E.

    1999-01-01

    The ultraviolet behaviour of the generating functional for hadronic weak interactions with |ΔS| = 1, 2 is investigated to one loop for a generic number of flavours and in the quenched approximation. New quenched chiral logarithms generated by the weak interactions can be accounted for via a redefin

  3. Stability and quench development study in small HTSC magnet

    NARCIS (Netherlands)

    Ilyin, Y.; Vysotski, V.S.; Kiss, T.; Takeo, M.; Okamoto, H.; Irie, F.

    2001-01-01

    Stability and quench development in a HTSC magnet have been experimentally studied with the transport current in the magnet being below or above the “thermal quench current” level. The magnet was tested at both cryocooler cooling and liquid nitrogen cooling, with and without background magnetic

  4. QUENCHING PROBLEMS OF DEGENERATE FUNCTIONAL REACTION-DIFFUSION EQUATION

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper is concerned with the quenching problem of a degenerate functional reaction-diffusion equation. The quenching problem and global existence of solution for the reaction-diffusion equation are derived and, some results of the positive steady state solutions for functional elliptic boundary value are also presented.

  5. Quenched transmission of light through ultrathin metal films

    DEFF Research Database (Denmark)

    Xiao, Sanshui; Mortensen, N. Asger

    2011-01-01

    We discuss optical properties of ultrathin metal films, with particular attention to the phenomenon of quenched transmission. Transmission of light through an optically ultrathin metal film with a thickness comparable to its skin depth is significant. We demonstrate the quenched transmission thro...

  6. Chiral and continuum extrapolation of partially quenched lattice results

    Energy Technology Data Exchange (ETDEWEB)

    C.R. Allton; W. Armour; D.B. Leinweber; A.W. Thomas; R.D. Young

    2005-04-01

    The vector meson mass is extracted from a large sample of partially quenched, two-flavor lattice QCD simulations. For the first time, discretization, finite-volume and partial quenching artifacts are treated in a unified chiral effective field theory analysis of the lattice simulation results.

  7. Angular dependence of jet quenching indicates its strong enhancement near the QCD phase transition.

    Science.gov (United States)

    Liao, Jinfeng; Shuryak, Edward

    2009-05-22

    We study dependence of jet quenching on matter density, using "tomography" of the fireball provided by RHIC data on azimuthal anisotropy v_{2} of high p_{t} hadron yield at different centralities. Slicing the fireball into shells with constant (entropy) density, we derive a "layer-wise geometrical limit" v_{2};{max} which is indeed above the data v_{2} QGP at T > T_{c}. One possible reason for such enhancement may be recent indications that the near-T_{c} region is a magnetic plasma of relatively light color-magnetic monopoles.

  8. AgInCd control rod failure in the QUENCH-13 bundle test

    Energy Technology Data Exchange (ETDEWEB)

    Sepold, L. [Forschungszentrum Karlsruhe, Institut fuer Materialforschung, Nuclear Safety Program (NUKLEAR), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)], E-mail: leo.sepold@imf.fzk.de; Lind, T. [Paul Scherrer Institut, Laboratory for Thermalhydralics (LTH), Department of Nuclear Energy and Safety (NES), 5232 Villigen PSI (Switzerland); Csordas, A. Pinter [Fuel Materials Department, HAS KFKI AEKI, 1121 Budapest (Hungary); Stegmaier, U.; Steinbrueck, M.; Stuckert, J. [Forschungszentrum Karlsruhe, Institut fuer Materialforschung, Nuclear Safety Program (NUKLEAR), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2009-09-15

    The QUENCH off-pile experiments performed at the Karlsruhe Research Center are to investigate the high-temperature behavior of Light Water Reactor (LWR) core materials under transient conditions and in particular the hydrogen source term resulting from the water injection into an uncovered LWR core. The typical LWR-type QUENCH test bundle, which is electrically heated, consists of 21 fuel rod simulators with a total length of approximately 2.5 m. The Zircaloy-4 rod claddings and the grid spacers are identical to those used in Pressurized Water Reactors (PWR) whereas the fuel is represented by ZrO{sub 2} pellets. In the QUENCH-13 experiment the single unheated fuel rod simulator in the center of the test bundle was replaced by a PWR-type control rod. The QUENCH-13 experiment consisting of pre-oxidation, transient, and quench water injection at the bottom of the test section investigated the effect of an AgInCd/stainless steel/Zircaloy-4 control rod assembly on early-phase bundle degradation and on reflood behavior. Furthermore, in the frame of the EU 6th Framework Network of Excellence SARNET, release and transport of aerosols of a failed absorber rod were to be studied in QUENCH-13, which was accomplished with help of aerosol measurements performed by PSI-Switzerland and AEKI-Hungary. Control rod failure was initiated by eutectic interaction of steel cladding and Zircaloy-4 guide tube and was indicated at about 1415 K by axial peak absorber and bundle temperature responses and additionally by the on-line aerosol monitoring system. Significant releases of aerosols and melt relocation from the control rod were observed at an axial peak bundle temperature of 1650 K. At a maximum bundle temperature of 1820 K reflood from the bottom was initiated with cold water at a flooding rate of 52 g/s. There was no noticeable temperature escalation during quenching. This corresponds to the small amount of about 1 g in hydrogen production during the quench phase (compared to 42 g

  9. Vitamin C conjugates of genotoxic lipid peroxidation products: Structural characterization and detection in human plasma

    OpenAIRE

    Sowell, John; Frei, Balz; Stevens, Jan F.

    2004-01-01

    α,β-Unsaturated aldehydes such as 4-hydroxy-2-nonenal (HNE) and other electrophilic lipid peroxidation (LPO) products may contribute to the pathogenesis of cancer, cardiovascular diseases, and other age-related diseases by cytotoxic, genotoxic, and proinflammatory mechanisms. The notion that vitamin C (ascorbic acid) acts as a biological antioxidant has been challenged recently by an in vitro study showing that ascorbic acid promotes, rather than inhibits, the formation of genotoxic LPO produ...

  10. The effects of added hydrogen on a helium atmospheric-pressure plasma jet ambient desorption/ionization source.

    Science.gov (United States)

    Wright, Jonathan P; Heywood, Matthew S; Thurston, Glen K; Farnsworth, Paul B

    2013-03-01

    We present mass spectrometric data demonstrating the effect that hydrogen has on a helium-based dielectric-barrier discharge (DBD) atmospheric-pressure plasma jet used as an ambient desorption/ionization (ADI) source. The addition of 0.9 % hydrogen to the helium support gas in a 35-W plasma jet increased signals for a range of test analytes, with enhancement factors of up to 68, without proportional increases in background levels. The changes in signal levels result from a combination of changes in the desorption kinetics from the surface and increased ion production in the gas phase. The enhancement in ADI-MS performance despite the quenching of key plasma species reported in earlier studies suggests that ionization with a H2/He plasma jet is the result of an alternate mechanism involving the direct generation of ionized hydrogen.

  11. Chiral Loops and Ghost States in the Quenched Scalar Propagator

    Energy Technology Data Exchange (ETDEWEB)

    W. Bardeen; A. Duncan; E. Eichten; N. Isgur; H. Thacker

    2001-06-01

    The scalar, isovector meson propagator is analyzed in quenched QCD, using the MQA pole-shifting ansatz to study the chiral limit. In addition to the expected short-range exponential falloff characteristic of a heavy scalar meson, the propagator also exhibits a longer-range, negative metric contribution which becomes pronounced for smaller quark masses. We show that this is a quenched chiral loop effect associated with the anomalous structure of the eta' propagator in quenched QCD. Both the time dependence and the quark mass dependence of this effect are well-described by a chiral loop diagram corresponding to an eta'-pi intermediate state, which is light and effectively of negative norm in the quenched approximation. The relevant parameters of the effective Lagrangian describing the scalar sector of the quenched theory are determined.

  12. Dynamics of Holographic Entanglement Entropy Following a Local Quench

    CERN Document Server

    Rangamani, Mukund; Vincart-Emard, Alexandre

    2015-01-01

    We discuss the behaviour of holographic entanglement entropy following a local quench in 2+1 dimensional strongly coupled CFTs. The entanglement generated by the quench propagates along an emergent light-cone, reminiscent of the Lieb-Robinson light-cone propagation of correlations in non-relativistic systems. We find the the speed of propagation is bounded from below by the entanglement tsunami velocity obtained earlier for global quenches in holographic systems, and from above by the speed of light. The former is realized for sufficiently broad quenches, while the latter pertains for well localized quenches. The non-universal behavior in the intermediate regime appears to stem from finite-size effects. We also note that the entanglement entropy of subsystems reverts to the equilibrium value exponentially fast, in contrast to a much slower equilibration seen in certain spin models.

  13. Study of jet quenching in heavy ion collisions at LHC using ATLAS detector

    CERN Document Server

    Štefko, Pavol

    2015-01-01

    Quark-Gluon Plasma (QGP) is one of the most extreme states of matter which exists only in extraordinary conditions of heavy-ion collisions that can be achieved at particle accelerators. Interactions between the partons and the hot, dense QGP are expected to cause the loss of the jet energy, which is phenomenon called jet quenching. In this talk we provide an introduction to the problematics of ultra-relativistic heavy ion collisions and we show how the jet quenching can be used to analyze the properties of QGP. We also present some “work in progress” results of the jet analysis done on the data taken by the ATLAS detector during the 2011 heavy-ion run at the LHC. Jets are studied as a function of collision centrality and dijet energy imbalance. Dijets are observed to be increasingly asymmetric with increasing centrality. The study of charged particles indicates an increase of yields of low- p T tracks in events with strongly quenched jets

  14. Design and implementation of quench detection instrumentation for TF magnet system of SST-1

    Energy Technology Data Exchange (ETDEWEB)

    Khristi, Y.; Sharma, A.N.; Doshi, K.; Banaudha, M.; Prasad, U.; Varmora, P.; Patel, D.; Pradhan, S., E-mail: subrata.s.pradhan@gmail.com

    2014-05-15

    Steady State Superconducting Tokamak-1 (SST-1) at Institute for Plasma Research (IPR), India is now in engineering validation phase. The assembled Toroidal Field (TF) magnet system of SST-1 will be operated at 10 kA of nominal current at helium cooled condition of 4.5 K. A reliable and fail proof quench detection (QD) system is essential for the safety and the investment protection requirements of the magnets. This QD system needs to continuously monitor all the superconducting coils, which include 16 TF magnets, return-loop, bus bars and current leads. In case of any event initiating the normal resistive zone and reaching thermal run-away, the QD system needs to trigger the magnet protection circuits. Precision instrumentation and control system with 204 signal channels had been developed for detection of quench anywhere in the entire TF magnet system. In the present configuration of quench detection scheme, the voltage drop across each double pancake (DP) of each TF coil are compared with its two adjacent DPs for the detection of normal zone and cancelation of inductive couples. Two identical redundant systems with one out of two configurations are successfully commissioned and tested at IPR. This paper describes the design and implementation of the QD system, Installation experience, validation test and initial results from the recent SST-1 magnet system charging.

  15. Multicapillary SDS-gel electrophoresis for the analysis of fluorescently labeled mAb preparations: a high throughput quality control process for the production of QuantiPlasma and PlasmaScan mAb libraries.

    Science.gov (United States)

    Székely, Andrea; Szekrényes, Akos; Kerékgyártó, Márta; Balogh, Attila; Kádas, János; Lázár, József; Guttman, András; Kurucz, István; Takács, László

    2014-08-01

    Molecular heterogeneity of mAb preparations is the result of various co- and post-translational modifications and to contaminants related to the production process. Changes in molecular composition results in alterations of functional performance, therefore quality control and validation of therapeutic or diagnostic protein products is essential. A special case is the consistent production of mAb libraries (QuantiPlasma™ and PlasmaScan™) for proteome profiling, quality control of which represents a challenge because of high number of mAbs (>1000). Here, we devise a generally applicable multicapillary SDS-gel electrophoresis process for the analysis of fluorescently labeled mAb preparations for the high throughput quality control of mAbs of the QuantiPlasma™ and PlasmaScan™ libraries. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Quantitative quenching evaluation and direct intracellular metabolite analysis in Penicillium chrysogenum.

    Science.gov (United States)

    Meinert, Sabine; Rapp, Sina; Schmitz, Katja; Noack, Stephan; Kornfeld, Georg; Hardiman, Timo

    2013-07-01

    Sustained progress in metabolic engineering methodologies has stimulated new efforts toward optimizing fungal production strains such as through metabolite analysis of Penicillium chrysogenum industrial-scale processes. Accurate intracellular metabolite quantification requires sampling procedures that rapidly stop metabolism (quenching) and avoid metabolite loss via the cell membrane (leakage). When sampling protocols are validated, the quenching efficiency is generally not quantitatively assessed. For fungal metabolomics, quantitative biomass separation using centrifugation is a further challenge. In this study, P. chrysogenum intracellular metabolites were quantified directly from biomass extracts using automated sampling and fast filtration. A master/slave bioreactor concept was applied to provide industrial production conditions. Metabolic activity during sampling was monitored by 13C tracing. Enzyme activities were efficiently stopped and metabolite leakage was absent. This work provides a reliable method for P. chrysogenum metabolomics and will be an essential base for metabolic engineering of industrial processes.

  17. Quench and partitioning steel: a new AHSS concept for automotive anti-intrusion applications

    Energy Technology Data Exchange (ETDEWEB)

    De Cooman, B.C. [Graduate Inst. for Ferrous Technology, Pohang Univ. of Science and Technology, Pohang (Korea); Speer, J.G. [Advanced Steel Processing and Products Research Centre, Colorado School of Mines, Golden, CO (United States)

    2006-09-15

    A new type of high strength, high toughness, martensitic steel, based on a newly proposed quench and partitioning (Q and P) process, is presented. This high strength martensitic grade is produced by the controlled low temperature partitioning of carbon from as-quenched martensite laths to retained inter-lath austenite under conditions where both low temperature transition carbide formation and cementite precipitation are suppressed. The contribution focuses on both the current understanding of the fundamental processes involved and includes a discussion of the technical feasibility of large-scale industrial production of these steels as sheet products. The Q and P process, which is carried out on steels with a lean composition, should be implemented easily on some current industrial continuous annealing and galvanizing lines. In addition, martensitic Q and P sheet steel is characterized by very favourable combinations of strength, ductility and toughness, which are particularly relevant for high strength anti-intrusion automotive parts. (orig.)

  18. Reference distribution functions for magnetically confined plasmas from the minimum entropy production theorem and the MaxEnt principle, subject to the scale-invariant restrictions

    Energy Technology Data Exchange (ETDEWEB)

    Sonnino, Giorgio, E-mail: gsonnino@ulb.ac.be [Université Libre de Bruxelles (U.L.B.), Department of Physics, Campus de la Plaine Code Postal 231 - Boulevard du Triomphe, 1050 Brussels (Belgium); Cardinali, Alessandro [EURATOM-ENEA Fusion Association, Via E. Fermi 45, C.P. 65-00044 Frascati, Rome (Italy); Steinbrecher, Gyorgy [EURATOM-MEdC Fusion Association, Physics Faculty, University of Craiova, Str. A.I. Cuza 13, 200585 Craiova (Romania); Peeters, Philippe [Université Libre de Bruxelles (U.L.B.), Department of Physics, Campus de la Plaine Code Postal 231 - Boulevard du Triomphe, 1050 Brussels (Belgium); Sonnino, Alberto [Université Catholique de Louvain (UCL), Ecole Polytechnique de Louvain (EPL), Rue Archimède, 1 bte L6.11.01, 1348 Louvain-la-Neuve (Belgium); Nardone, Pasquale [Université Libre de Bruxelles (U.L.B.), Department of Physics, Campus de la Plaine Code Postal 231 - Boulevard du Triomphe, 1050 Brussels (Belgium)

    2013-12-09

    We derive the expression of the reference distribution function for magnetically confined plasmas far from the thermodynamic equilibrium. The local equilibrium state is fixed by imposing the minimum entropy production theorem and the maximum entropy (MaxEnt) principle, subject to scale invariance restrictions. After a short time, the plasma reaches a state close to the local equilibrium. This state is referred to as the reference state. The aim of this Letter is to determine the reference distribution function (RDF) when the local equilibrium state is defined by the above mentioned principles. We prove that the RDF is the stationary solution of a generic family of stochastic processes corresponding to an universal Landau-type equation with white parametric noise. As an example of application, we consider a simple, fully ionized, magnetically confined plasmas, with auxiliary Ohmic heating. The free parameters are linked to the transport coefficients of the magnetically confined plasmas, by the kinetic theory.

  19. ITER Side Correction Coil Quench model and analysis

    Science.gov (United States)

    Nicollet, S.; Bessette, D.; Ciazynski, D.; Duchateau, J. L.; Gauthier, F.; Lacroix, B.

    2016-12-01

    Previous thermohydraulic studies performed for the ITER TF, CS and PF magnet systems have brought some important information on the detection and consequences of a quench as a function of the initial conditions (deposited energy, heated length). Even if the temperature margin of the Correction Coils is high, their behavior during a quench should also be studied since a quench is likely to be triggered by potential anomalies in joints, ground fault on the instrumentation wires, etc. A model has been developed with the SuperMagnet Code (Bagnasco et al., 2010) for a Side Correction Coil (SCC2) with four pancakes cooled in parallel, each of them represented by a Thea module (with the proper Cable In Conduit Conductor characteristics). All the other coils of the PF cooling loop are hydraulically connected in parallel (top/bottom correction coils and six Poloidal Field Coils) are modeled by Flower modules with equivalent hydraulics properties. The model and the analysis results are presented for five quench initiation cases with/without fast discharge: two quenches initiated by a heat input to the innermost turn of one pancake (case 1 and case 2) and two other quenches initiated at the innermost turns of four pancakes (case 3 and case 4). In the 5th case, the quench is initiated at the middle turn of one pancake. The impact on the cooling circuit, e.g. the exceedance of the opening pressure of the quench relief valves, is detailed in case of an undetected quench (i.e. no discharge of the magnet). Particular attention is also paid to a possible secondary quench detection system based on measured thermohydraulic signals (pressure, temperature and/or helium mass flow rate). The maximum cable temperature achieved in case of a fast current discharge (primary detection by voltage) is compared to the design hot spot criterion of 150 K, which includes the contribution of helium and jacket.

  20. Surface recombination of oxygen atoms in O2 plasma at increased pressure: II. Vibrational temperature and surface production of ozone

    Science.gov (United States)

    Lopaev, D. V.; Malykhin, E. M.; Zyryanov, S. M.

    2011-01-01

    Ozone production in an oxygen glow discharge in a quartz tube was studied in the pressure range of 10-50 Torr. The O3 density distribution along the tube diameter was measured by UV absorption spectroscopy, and ozone vibrational temperature TV was found comparing the calculated ab initio absorption spectra with the experimental ones. It has been shown that the O3 production mainly occurs on a tube surface whereas ozone is lost in the tube centre where in contrast the electron and oxygen atom densities are maximal. Two models were used to analyse the obtained results. The first one is a kinetic 1D model for the processes occurring near the tube walls with the participation of the main particles: O(3P), O2, O2(1Δg) and O3 molecules in different vibrational states. The agreement of O3 and O(3P) density profiles and TV calculated in the model with observed ones was reached by varying the single model parameter—ozone production probability (\\gamma_{O_{3}}) on the quartz tube surface on the assumption that O3 production occurs mainly in the surface recombination of physisorbed O(3P) and O2. The phenomenological model of the surface processes with the participation of oxygen atoms and molecules including singlet oxygen molecules was also considered to analyse \\gamma_{O_{3}} data obtained in the kinetic model. A good agreement between the experimental data and the data of both models—the kinetic 1D model and the phenomenological surface model—was obtained in the full range of the studied conditions that allowed consideration of the ozone surface production mechanism in more detail. The important role of singlet oxygen in ozone surface production was shown. The O3 surface production rate directly depends on the density of physisorbed oxygen atoms and molecules and can be high with increasing pressure and energy inputted into plasma while simultaneously keeping the surface temperature low enough. Using the special discharge cell design, such an approach opens up the

  1. Plasma advanced glycation end products (AGEs) and NF-κB activity are independent determinants of diastolic and pulse pressure

    DEFF Research Database (Denmark)

    Sourris, Karly C; Lyons, Jasmine G; Dougherty, Sonia L;

    2013-01-01

    Abstract Background: High levels of circulating advanced glycation end products (AGEs) can initiate chronic low-grade activation of the immune system (CLAIS) with each of these factors independently associated with cardiovascular (CV) morbidity and mortality. Therefore, our objective was to chara......Abstract Background: High levels of circulating advanced glycation end products (AGEs) can initiate chronic low-grade activation of the immune system (CLAIS) with each of these factors independently associated with cardiovascular (CV) morbidity and mortality. Therefore, our objective...... was to characterize the relationship between serum AGEs, CLAIS and other risk factors for CV disease in normotensive non-diabetic individuals. Methods: We measured body mass index (BMI), waist-to-hip ratio (WHR), blood pressure, lipid and glucose profile in 44 non-diabetic volunteers (17 female, 27 males......). Carboxymethyl-lysine (CML) was measured by ELISA as a marker for circulating AGEs and NF-κB p65 activity as an inflammatory marker by DNA-binding in peripheral blood mononuclear cells lysates (PBMC). Results: Plasma CML concentrations were related to diastolic blood pressure (r=-0.51, p...

  2. Total iodine in infant formula and nutritional products by inductively coupled plasma/mass spectrometry: First Action 2012.14.

    Science.gov (United States)

    Pacquette, Lawrence H; Levenson, Alan M; Thompson, Joseph J; Dowell, Dawn

    2013-01-01

    After an assessment of data generated from a single-laboratory validation study published in the Journal of AOAC INTERNATIONAL 95, 169-176 (2012), a method for determining the total level of iodine in infant formula and nutritional products was presented for consideration for adoption by AOAC during the AOAC Annual Meeting held September 30-October 3, 2012 in Las Vegas, NV. An Expert Review Panel on Infant Formula and Adult Nutritionals concluded that the method met the established standard method performance requirements, and approved the method as AOAC Official First Action. The method involves digestion of the sample with nitric acid in a closed vessel microwave oven, followed by determination by inductively coupled plasma/MS using tellurium as the internal standard. The method LOQ for total iodine was 1.5 microg/100 g, but a practical LOQ was used at 5 microg/100 g total iodine. The analytical range of the method was 5-100 microg/100 g total iodine. The recoveries from 15 spiked nutritional products ranged from 90 to 105%.

  3. Mesenchymal stromal cell proliferation, gene expression and protein production in human platelet-rich plasma-supplemented media.

    Science.gov (United States)

    Amable, Paola Romina; Teixeira, Marcus Vinicius Telles; Carias, Rosana Bizon Vieira; Granjeiro, José Mauro; Borojevic, Radovan

    2014-01-01

    Platelet-rich plasma (PRP) is increasingly used as a cell culture supplement, in order to reduce the contact of human cells with animal-derived products during in vitro expansion. The effect of supplementation changes on cell growth and protein production is not fully characterized. Human mesenchymal stromal cells from bone marrow, adipose tissue and Wharton's Jelly were isolated and cultured in PRP-supplemented media. Proliferation, in vitro differentiation, expression of cell surface markers, mRNA expression of key genes and protein secretion were quantified. 10% PRP sustained five to tenfold increased cell proliferation as compared to 10% fetal bovine serum. Regarding cell differentiation, PRP reduced adipogenic differentiation and increased calcium deposits in bone marrow and adipose tissue-mesenchymal stromal cells. Wharton's Jelly derived mesenchymal stromal cells secreted higher concentrations of chemokines and growth factors than other mesenchymal stromal cells when cultured in PRP-supplemented media. Bone marrow derived mesenchymal stromal cells secreted higher concentrations of pro-inflammatory and pro-angiogenic proteins. Mesenchymal stromal cells isolated from adipose tissue secreted higher amounts of extracellular matrix components. Mesenchymal stromal cells purified from different tissues have distinct properties regarding differentiation, angiogenic, inflammatory and matrix remodeling potential when cultured in PRP supplemented media. These abilities should be further characterized in order to choose the best protocols for their therapeutic use.

  4. Silicon nanocrystal production through non-thermal plasma synthesis: a comparative study between silicon tetrachloride and silane precursors

    Science.gov (United States)

    Yasar-Inceoglu, Ozgul; Lopez, Thomas; Farshihagro, Ebrahim; Mangolini, Lorenzo

    2012-06-01

    Silicon nanocrystals with sizes between 5 and 10 nm have been produced in a non-thermal plasma reactor using silicon tetrachloride as precursor. We demonstrate that high-quality material can be produced with this method and that production rates as high as 140 mg h-1 can be obtained, with a maximum precursor utilization rate of roughly 50%. Compared to the case in which particles are produced using silane as the main precursor, the gas composition needs to be modified and hydrogen needs to be added to the mixture to enable the nucleation and growth of the powder. The presence of chlorine in the system leads to the production of nanoparticles with a chlorine terminated surface which is significantly less robust against oxidation in air compared to the case of a hydrogen terminated surface. We also observe that significantly higher power input is needed to guarantee the formation of crystalline particles, which is a consequence not only of the different gas-phase composition, but also of the influence of chlorine on the stability of the crystalline structure.

  5. Quenching of singlet oxygen by pyocyanin and related phenazines.

    Science.gov (United States)

    Reszka, Krzysztof J; Bilski, Piotr J; Britigan, Bradley E

    2010-01-01

    Pseudomonas aeruginosa is a human pathogen, which causes infections of various organs, including lung, skin and eye, particularly in individuals who are immunocompromised. Pyocyanin (1-hydroxy-5-methylphenazine), a cytotoxic pigment secreted by the bacterium, is among the factors that contribute to virulence of this pathogen. We have previously shown that rose bengal and riboflavin photosensitize oxidation of pyocyanin to a product(s) with diminished reactivity and toxicity. Singlet oxygen was suggested as the major oxidant, based on the inhibitory effect of sodium azide. In the present study, we used the time resolved technique to investigate direct interaction of pyocyanin and related phenazines (1-hydroxyphenazine [1-OH-Phen], 1-methoxy-5-methylphenazine [1-MeO-PCN] and phenazine methosulfate [PMS]) with (1)O(2). The rate constants for the (1)O(2) quenching (physical + chemical) by pyocyanin and 1-OH-Phen in D(2)O buffer (pD approximately 7.2) have been determined to be 4.8 x 10(8) and 6.8 x 10(8) M(-1) s(-1), respectively. 1-MeO-PCN and PMS were markedly less efficient (1)O(2) quenchers. Among the phenazines studied only phenazine methosulfate photogenerated (1)O(2) (Phi((1)O(2)) = 0.56 in acetonitrile). Interaction of (1)O(2) with pyocyanin and other related phenazines produced by the bacteria may be important in determining the potential utility of photochemical/pharmacological approaches to eradicate P. aeruginosa from infected tissues.

  6. Quench Protection and Magnet Supply Requirements for the MICEFocusingand Coupling Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Green, Michael A.; Witte, Holger

    2005-06-08

    This report discusses the quench protection and power supply requirements of the MICE superconducting magnets. A section of the report discusses the quench process and how to calculate the peak voltages and hotspot temperature that result from a magnet quench. A section of the report discusses conventional quench protection methods. Thermal quench back from the magnet mandrel is also discussed. Selected quench protection methods that result in safe quenching of the MICE focusing and coupling magnets are discussed. The coupling of the MICE magnets with the other magnets in the MICE is described. The consequences of this coupling on magnet charging and quenching are discussed. Calculations of the quenching of a magnet due quench back from circulating currents induced in the magnet mandrel due to quenching of an adjacent magnet are discussed. The conclusion of this report describes how the MICE magnet channel will react when one or magnets in that channel are quenched.

  7. 40 CFR 1065.370 - CLD CO2 and H2O quench verification.

    Science.gov (United States)

    2010-07-01

    ... analyzer uses quench compensation algorithms that utilize H2O and/or CO2 measurement instruments, evaluate quench with these instruments active and evaluate quench with the compensation algorithms applied....

  8. Comparisons of four quench methods for high temperature Syngas-Exergy Analyses

    Science.gov (United States)

    Liu, Y. H.; Chen, W.; Che, D. F.; Cao, Z. D.

    2010-03-01

    Entrained flow slagging gasifiers have been found in many applications, one of which is IGCC. The quench of high temperature syngas from first stage of entrained flow slagging gasifiers is of great importance for the availability of gasifiers, and it influences the economical running of utilization system. Four kinds of quench methods including water quench, gas quench, radiant quench and chemical quench, are investigated by Gibbs free energy minimization and exergy analyses. The exergy distributions of the streams into and out of each quench system are obtained. The results show that exergy loss of water quench is the biggest, and the exergy loss of chemical quench is the least and can be neglectable. The exergy losses of the other two quench methods are comparable, which are only 1/3 smaller than that of water quench. Chemical quench not only features in lower oxygen consumption as well as a higher cold gas efficiency, but also has high exergy efficiency.

  9. Synthesis of functional nanocrystallites through reactive thermal plasma processing

    Directory of Open Access Journals (Sweden)

    Takamasa Ishigaki and Ji-Guang Li

    2007-01-01

    Full Text Available A method of synthesizing functional nanostructured powders through reactive thermal plasma processing has been developed. The synthesis of nanosized titanium oxide powders was performed by the oxidation of solid and liquid precursors. Quench gases, either injected from the shoulder of the reactor or injected counter to the plasma plume from the bottom of the reactor, were used to vary the quench rate, and therefore the particle size, of the resultant powders. The experimental results are well supported by numerical analysis on the effects of the quench gas on the flow pattern and temperature field of the thermal plasma as well as on the trajectory and temperature history of the particles. The plasma-synthesized TiO2 nanoparticles showed phase preferences different from those synthesized by conventional wet-chemical processes. Nanosized particles of high crystallinity and nonequilibrium chemical composition were formed in one step via reactive thermal plasma processing.

  10. Higher plasma levels of advanced glycation end products are associated with incident cardiovascular disease and all-cause mortality in type 1 diabetes

    DEFF Research Database (Denmark)

    Nin, Johanna W; Jorsal, Anders; Ferreira, Isabel;

    2011-01-01

    OBJECTIVE: To investigate the associations of plasma levels of advanced glycation end products (AGEs) with incident cardiovascular disease (CVD) and all-cause mortality in type 1 diabetes and the extent to which any such associations could be explained by endothelial and renal dysfunction, low...

  11. EFFECT OF HIGH-FAT DIETS SUPPLEMENTED WITH OKARA SOYBEAN BY-PRODUCT ON LIPID PROFILES OF PLASMA, LIVER AND FAECES IN SYRIAN HAMSTERS

    Science.gov (United States)

    The main components of okara, a by-product from soybean, is dietary fiber and protein. Both dietary fiber and protein can reduce plasma cholesterol. In this study we fed okara based diets with different amounts of fiber, protein and isoflavones to determine the most important component for choleste...

  12. A perturbative framework for jet quenching

    Science.gov (United States)

    Zapp, Korinna C.; Krauss, Frank; Wiedemann, Urs A.

    2013-03-01

    We present a conceptually new framework for describing jet evolution in the dense medium produced in ultra-relativistic nucleus-nucleus collisions using perturbative QCD and its implementation into the Monte Carlo event generator Jewel. The rescattering of hard partons in the medium is modelled by infrared continued pQCD matrix elements supplemented with parton showers. The latter approximate higher order real-emission matrix elements and thus generate medium-induced gluon emissions. The interplay between different emissions is governed by their formation times. The destructive interference between subsequent scattering processes, the non-Abelian version of the Landau-Pomeranchuk-Migdal effect, is also taken into account. In this way the complete radiation pattern is consistently treated in a uniform way. Results obtained within this minimal and theoretically well constrained framework are compared with a variety of experimental data susceptible to jet-quenching effects at both RHIC and the LHC. Overall, a good agreement between data and simulation is found. This new framework also allows to identify and quantify the dominant uncertainties in the simulation, and we show some relevant examples for this.

  13. Quenched Heavy-Light Decay Constants

    CERN Document Server

    Baxter, R M; Bowler, K C; Collins, S; Henty, D S; Kenway, R D; Richards, D G; Shanahan, H P; Simone, J N; Simpson, A D; Wilkes, B E; Ewing, A K; Lellouch, L P; Sachrajda, Christopher T C; Wittig, H

    1994-01-01

    We present results for heavy-light decay constants, using both propagating quarks and the static approximation, in O(a)-improved, quenched lattice QCD. At beta=6.2 on a 24^3x48 lattice we find f_D=185 +4-3(stat)+42-7(syst) MeV, f_B=160 +6-6 +53-19 MeV, f_{D_s}/f_D=1.18 +2-2 and f_{B_s}/f_B=1.22 +4-3, in good agreement with earlier studies. From the static theory we obtain f_B^stat=253 +16-15 +105-14 MeV. We also present results from a simulation at beta=6.0 on a 16^3x48 lattice, which are consistent with those at beta=6.2. In order to study the effects of improvement, we present a direct comparison of the results using both the Wilson and the improved action at beta=6.0.

  14. Nonequilibrium States of a Quenched Bose Gas

    Science.gov (United States)

    Ling, Hong; Kain, Ben

    2014-05-01

    Yin and Radzihovsky [Phys. Rev. A 88, 063611 (2014)] recently developed a self-consistent extension of a Bogoliubov theory, in which the condensate number density, nc, is treated as a mean field that changes with time in order to analyze a JILA experiment by Makotyn et al. [Nature Physics doi:10.1038/nphys2850 (2014)] on a 85Rb Bose gas following a deep quench to a large scattering length. We apply this theory to construct a set of closed equations that highlight the role of dnc/dt, which is to induce an effective interaction between quasiparticles. We show analytically that such a system supports a steady state characterized by a constant condensate density and a steady but periodically changing momentum distribution, whose time average is described exactly by the generalized Gibbs ensemble. We discuss how the dnc/dt-induced effective interaction, which cannot be ignored on the grounds of the adiabatic approximation for modes near the gapless Goldstone mode, can affect experimentally measurable quantities such as Tan's contact. This work is supported in part by the US Army Research Office under Grant No. W911NF-10-1-0096 and in part by the US National Science Foundation under Grant No. PHY11-25915.

  15. Quenching parameter in a holographic thermal QCD

    CERN Document Server

    Patra, Binoy Krishna

    2016-01-01

    We have calculated the quenching parameter, $\\hat{q}$ in a model-independent way using the gauge-gravity duality. In earlier calculations, the geometry in the gravity side at finite temperature was usually taken as the pure AdS blackhole metric for which the dual gauge theory becomes conformally invariant unlike QCD. Therefore we use a metric which incorporates the fundamental quarks by embedding the coincident D7 branes in the Klebanov-Tseytlin background and a finite temperature is switched on by inserting a black hole into the background, known as OKS-BH metric. Further inclusion of an additional UV cap to the metric prepares the dual gauge theory to run similar to thermal QCD. Moreover $\\hat{q}$ is usually defined in the literature from the Glauber-model perturbative QCD evaluation of the Wilson loop, which has no reasons to hold if the coupling is large and is thus against the main idea of gauge-gravity duality. Thus we use an appropriate definition of $\\hat{q}$: $\\hat{q} L^- = 1/L^2$, where $L$ is the s...

  16. Quorum Quenching Agents: Resources for Antivirulence Therapy

    Directory of Open Access Journals (Sweden)

    Kaihao Tang

    2014-05-01

    Full Text Available The continuing emergence of antibiotic-resistant pathogens is a concern to human health and highlights the urgent need for the development of alternative therapeutic strategies. Quorum sensing (QS regulates virulence in many bacterial pathogens, and thus, is a promising target for antivirulence therapy which may inhibit virulence instead of cell growth and division. This means that there is little selective pressure for the evolution of resistance. Many natural quorum quenching (QQ agents have been identified. Moreover, it has been shown that many microorganisms are capable of producing small molecular QS inhibitors and/or macromolecular QQ enzymes, which could be regarded as a strategy for bacteria to gain benefits in competitive environments. More than 30 species of marine QQ bacteria have been identified thus far, but only a few of them have been intensively studied. Recent studies indicate that an enormous number of QQ microorganisms are undiscovered in the highly diverse marine environments, and these marine microorganism-derived QQ agents may be valuable resources for antivirulence therapy.

  17. Molecular insights into Zeaxanthin-dependent quenching in higher plants

    Science.gov (United States)

    Xu, Pengqi; Tian, Lijin; Kloz, Miroslav; Croce, Roberta

    2015-01-01

    Photosynthetic organisms protect themselves from high-light stress by dissipating excess absorbed energy as heat in a process called non-photochemical quenching (NPQ). Zeaxanthin is essential for the full development of NPQ, but its role remains debated. The main discussion revolves around two points: where does zeaxanthin bind and does it quench? To answer these questions we have followed the zeaxanthin-dependent quenching from leaves to individual complexes, including supercomplexes. We show that small amounts of zeaxanthin are associated with the complexes, but in contrast to what is generally believed, zeaxanthin binding per se does not cause conformational changes in the complexes and does not induce quenching, not even at low pH. We show that in NPQ conditions zeaxanthin does not exchange for violaxanthin in the internal binding sites of the antennas but is located at the periphery of the complexes. These results together with the observation that the zeaxanthin-dependent quenching is active in isolated membranes, but not in functional supercomplexes, suggests that zeaxanthin is acting in between the complexes, helping to create/participating in a variety of quenching sites. This can explain why none of the antennas appears to be essential for NPQ and the multiple quenching mechanisms that have been observed in plants. PMID:26323786

  18. Quench simulations for superconducting elements in the LHC accelerator

    CERN Document Server

    Sonnemann, F

    2000-01-01

    The design of he protection system for he superconducting elements in an accel- erator such as the Large Hadron Collider (LHC),now under construction at CERN, requires a detailed understanding of the hermo-hydraulic and electrodynamic pro- cesses during a quench.A numerical program (SPQR -Simulation Program for Quench Research)has been developed o evaluate temperature and voltage dis ri- butions during a quench as a func ion of space and ime.The quench process is simulated by approximating the heat balance equation with the finite di fference method in presence of variable cooling and powering conditions.The simulation predicts quench propagation along a superconducting cable,forced quenching with heaters,impact of eddy curren s induced by a magnetic field change,and heat trans- fer hrough an insulation layer in o helium,an adjacen conductor or other material. The simulation studies allowed a better understanding of experimental quench data and were used for determining the adequ...

  19. Systematic study of particle quenching in organic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Santiago, L.M.; Bagán, H. [Department of Analytical Chemistry of the University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain); Tarancón, A., E-mail: alex.tarancon@ub.edu [Department of Analytical Chemistry of the University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain); Rauret, G.; Garcia, J.F. [Department of Analytical Chemistry of the University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain)

    2013-01-11

    Among the different factors that affect measurements by organic scintillators, the majority of attention has been focused on those related to the scintillator (i.e., ionization, chemical, color and optical quenching), and less attention has been paid to the loss of energy before the particle (i.e., alpha or beta) arrives at the scintillator (i.e., particle quenching). This study evaluates the effect of particle quenching in different scintillation methods (i.e., using two plastic scintillation microspheres (PSm1 and PSm2), liquid scintillator and gel scintillator) by measuring solutions that contain increasing concentrations of NaCl, BaCl{sub 2} and glycerin. The results show the importance of particle quenching in PSm measurements because detection efficiency decreases with increasing concentrations of the quenching component, although the spectrum position and external standard parameter remain constant. The results have shown evidence of particle quenching, although at a lower magnitude, in the liquid scintillation or gel scintillation measurements. Moreover, the use of two PSm with different diameters and salty compound that alters the equilibrium of the liquid and gel emulsions also exemplified the importance of the transmission of optical photons through different scintillation media (i.e., optical quenching). Improvement and deterioration of the optical conditions on the scintillation media is manifested as a movement of the spectrum to higher and lower energies, respectively. The results obtained with PSm were confirmed by Monte Carlo simulation.

  20. The Mass Dependence of Dwarf Satellite Galaxy Quenching

    CERN Document Server

    Slater, Colin T

    2014-01-01

    We combine observations of the Local Group with data from the NASA-Sloan Atlas to show the variation in the quenched fraction of satellite galaxies from low mass dwarf spheroidals and dwarf irregulars to more massive dwarfs similar to the Magellanic clouds. While almost all of the low mass ($M_\\star \\lesssim 10^7$ $M_\\odot$) dwarfs are quenched, at higher masses the quenched fraction decreases to approximately 40-50%. This change in the quenched fraction is large, and suggests a sudden change in the effectiveness of quenching that correlates with satellite mass. We combine this observation with models of satellite infall and ram pressure stripping to show that the low mass satellites must quench within 1-2 Gyr of pericenter passage to maintain a high quenched fraction, but that many more massive dwarfs must continue to form stars today even though they likely fell in to their host >5 Gyr ago. We also characterize how the susceptibility of dwarfs to ram pressure must vary as a function of mass if it is to acco...