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Sample records for high density ion

  1. High current density ion source

    International Nuclear Information System (INIS)

    King, H.J.

    1977-01-01

    A high-current-density ion source with high total current is achieved by individually directing the beamlets from an electron bombardment ion source through screen and accelerator electrodes. The openings in these screen and accelerator electrodes are oriented and positioned to direct the individual beamlets substantially toward a focus point. 3 figures, 1 table

  2. HIGH DENSITY QCD WITH HEAVY-IONS

    CERN Multimedia

    The Addendum 1 to Volume 2 of the CMS Physics TDR has been published The Heavy-Ion analysis group completed the writing of a TDR summarizing the CMS plans in using heavy ion collisions to study high density QCD. The document was submitted to the LHCC in March and presented in the Open Session of the LHCC on May 9th. The study of heavy-ion physics at the LHC is promising to be very exciting. LHC will open a new energy frontier in ultra-relativistic heavy-ion physics. The collision energy of heavy nuclei at sNN = 5.5 TeV will be thirty times larger than what is presently available at RHIC. We will certainly probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research programme is to study the fundamental theory of the strong interaction - Quantum Chromodynamics (QCD) - in extreme conditions of temperature, density and parton momentum fraction (low-x). Such studies, with impressive experimental and theoretical advances in recent years thanks to the wealth of high-qua...

  3. Foldable, High Energy Density Lithium Ion Batteries

    Science.gov (United States)

    Suresh, Shravan

    Lithium Ion Batteries (LIBs) have become ubiquitous owing to its low cost, high energy density and, power density. Due to these advantages, LIBs have garnered a lot of attention as the primary energy storage devices in consumer electronics and electric vehicles. Recent advances in the consumer electronics research and, the drive to reduce greenhouse gases have created a demand for a shape conformable, high energy density batteries. This thesis focuses on the aforementioned two aspects of LIBs: (a) shape conformability (b) energy density and provides potential solutions to enhance them. This thesis is divided into two parts viz. (i) achieving foldability in batteries and, (ii) improving its energy density. Conventional LIBs are not shape conformable due to two limitations viz. inelasticity of metallic foils, and delamination of the active materials while bending. In the first part of the thesis (in Chapter 3), this problem is solved by replacing metallic current collector with Carbon Nanotube Macrofilms (CNMs). CNMs are superelastic films comprising of porous interconnected nanotube network. Using Molecular Dynamics (MD) simulation, we found that in the presence of an interconnected nanotube network CNMs can be fully folded. This is because the resultant stress due to bending and, the effective bending angle at the interface is reduced due to the network of nanotubes. Hence, unlike an isolated nanotube (which ruptures beyond 120 degrees of bending), a network of nanotubes can be completely folded. Thus, by replacing metallic current collector foils with CNMs, the flexibility limitation of a conventional LIB can be transcended. The second part of this thesis focusses on enhancing the energy density of LIBs. Two strategies adopted to achieve this goal are (a) removing the dead weight of the batteries, and (b) incorporating high energy density electrode materials. By incorporating CNMs, the weight of the batteries was reduced by 5-10 times due to low mass loading of

  4. High current density ion beam measurement techniques

    International Nuclear Information System (INIS)

    Ko, W.C.; Sawatzky, E.

    1976-01-01

    High ion beam current measurements are difficult due to the presence of the secondary particles and beam neutralization. For long Faraday cages, true current can be obtained only by negative bias on the target and by summing the cage wall and target currents; otherwise, the beam will be greatly distorted. For short Faraday cages, a combination of small magnetic field and the negative target bias results in correct beam current. Either component alone does not give true current

  5. Highly Compressed Ion Beams for High Energy Density Science

    CERN Document Server

    Friedman, Alex; Briggs, Richard J; Callahan, Debra; Caporaso, George; Celata, C M; Davidson, Ronald C; Faltens, Andy; Grant-Logan, B; Grisham, Larry; Grote, D P; Henestroza, Enrique; Kaganovich, Igor D; Lee, Edward; Lee, Richard; Leitner, Matthaeus; Nelson, Scott D; Olson, Craig; Penn, Gregory; Reginato, Lou; Renk, Tim; Rose, David; Sessler, Andrew M; Staples, John W; Tabak, Max; Thoma, Carsten H; Waldron, William; Welch, Dale; Wurtele, Jonathan; Yu, Simon

    2005-01-01

    The Heavy Ion Fusion Virtual National Laboratory (HIF-VNL) is developing the intense ion beams needed to drive matter to the High Energy Density (HED) regimes required for Inertial Fusion Energy (IFE) and other applications. An interim goal is a facility for Warm Dense Matter (WDM) studies, wherein a target is heated volumetrically without being shocked, so that well-defined states of matter at 1 to 10 eV are generated within a diagnosable region. In the approach we are pursuing, low to medium mass ions with energies just above the Bragg peak are directed onto thin target "foils," which may in fact be foams or "steel wool" with mean densities 1% to 100% of solid. This approach complements that being pursued at GSI, wherein high-energy ion beams deposit a small fraction of their energy in a cylindrical target. We present the requirements for warm dense matter experiments, and describe suitable accelerator concepts, including novel broadband traveling wave pulse-line, drift-tube linac, RF, and single-gap approa...

  6. High baryon density from relativistic heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Y.; Kahana, S.H. [Brookhaven National Lab., Upton, NY (United States); Schlagel, T.J. [Brookhaven National Lab., Upton, NY (United States)]|[State Univ. of New York, Stony Brook, NY (United States)

    1993-10-01

    A quantitative model, based on hadronic physics, is developed and applied to heavy ion collisions at BNL-AGS energies. This model is in excellent agreement with observed particle spectra in heavy ion collisions using Si beams, where baryon densities of three and four times the normal nuclear matter density ({rho}{sub 0}) are reached. For Au on Au collisions, the authors predict the formation of matter at very high densities (up to 10 {rho}{sub 0}).

  7. Volume generation of negative ions in high density hydrogen discharges

    International Nuclear Information System (INIS)

    Hiskes, J.R.; Karo, A.M.

    1983-01-01

    A parametric survey is made of a high-density tandem two-chamber hydrogen negative ion system. The optimum extracted negative ion current densities are sensitive to the atom concentration in the discharge and to the system scale length. For scale lengths ranging from 10 cm to 0.1 cm optimum current densities range from of order 1 to 100 mA cm -2 , respectively

  8. High energy density in matter produced by heavy ion beams

    International Nuclear Information System (INIS)

    1987-08-01

    This annual report summarizes the results of research carried out in 1986 within the framework of the program 'High Energy Density in Matter Produced by Heavy Ion Beams' which is funded by the Federal Ministry for Research and Technology. Its initial motivation and its ultimate goal is the question whether inertial confinement can be achieved by intense beams of heavy ions. (orig./HSI)

  9. Moderate energy ions for high energy density physics experiments

    International Nuclear Information System (INIS)

    Grisham, L.R.

    2004-01-01

    This paper gives the results of a preliminary exploration of whether moderate energy ions (≅0.3-3 MeV/amu) could be useful as modest-cost drivers for high energy density physics experiments. It is found that if the target thickness is chosen so that the ion beam enters and then leaves the target in the vicinity of the peak of the dE/dX (stopping power) curve, high uniformity of energy deposition may be achievable while also maximizing the amount of energy per beam particle deposited within the target

  10. Numerical analysis of energy density and particle density in high energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Fu Yuanyong; Lu Zhongdao

    2004-01-01

    Energy density and particle density in high energy heavy-ion collisions are calculated with infinite series expansion method and Gauss-Laguerre formulas in numerical integration separately, and the results of these two methods are compared, the higher terms and linear terms in series expansion are also compared. The results show that Gauss-Laguerre formulas is a good method in calculations of high energy heavy-ion collisions. (author)

  11. DIAGNOSTICS FOR ION BEAM DRIVEN HIGH ENERGY DENSITY PHYSICS EXPERIMENTS

    International Nuclear Information System (INIS)

    Bieniosek, F.M.; Henestroza, E.; Lidia, S.; Ni, P.A.

    2010-01-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30-mA K + beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (VISAR), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  12. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    International Nuclear Information System (INIS)

    Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2008-01-01

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state

  13. High energy density in matter produced by heavy ion beams

    International Nuclear Information System (INIS)

    1989-07-01

    This Annual Report summarizes research activities carried out in 1988 in the framework of the government-funded program 'High Energy Density in Matter produced by Heavy Ion Beams'. It addresses fundamental problems of the generation of heavy ion beams and the investigation of hot dense plasmas produced by these beams. Its initial motivation and its long-term goal is the feasibility of inertial confinement fusion by intense heavy ion beams. Two outstanding events deserve to be mentioned explicity, the Heavy Ion Inertial Fusion Conference held in Darmstadt and organized by GSI end of June and the first heavy ion beam injected into the new SIS facility in November. The former event attracted more than hundred scientists for three days to the 4th Conference in this field. This symposium showed the impressive progress since the last conference in Washington two years ago. In particular the first beams in MBE-4 at LBL and results of beam plasma interaction experiments at GSI open new directions for future investigations. The ideas for non-Lionvillean injection into storage rings presented by Carlo Rubbia will bring the discussion of driver scenarios into a new stage. The latter event is a milestone for both machine and target experiments. It characterizes the beginning of the commissioning phase for the new SIS/ESR facility which will be ready for experiments at the end of this year. The commissioning of SIS is on schedule and first experiments can start at the beginning of 1990. A status report of the accelerator project is included. Theoretical activities were continued as in previous years, many of them providing guide lines for future experiments, in particular for the radiation transport aspects and for beam-plasma interaction. (orig.)

  14. High energy density in matter produced by heavy ion beams

    International Nuclear Information System (INIS)

    1986-05-01

    In this report the activities of the GSI Darmstadt (FRG) during 1985 concerning inertial confinement fusion by heavy ion beams. Short communications and abstracts are presented concerning a Z-pinch experiment, heavy ion pumped lasers and X-ray spectroscopy, the study of ion-ion collisions, a RFQ development and beam transport studies, accelerator theory, targets for SIS/ESR experiments, the rayleigh-Taylor instability, studies on the equation of state for matter under high pressure, as well as the development of computer codes. (HSI)

  15. Studies in High Current Density Ion Sources for Heavy Ion Fusion Applications

    Energy Technology Data Exchange (ETDEWEB)

    Chacon-Golcher, Edwin [Univ. of California, Berkeley, CA (United States)

    2002-06-01

    This dissertation develops diverse research on small (diameter ~ few mm), high current density (J ~ several tens of mA/cm2) heavy ion sources. The research has been developed in the context of a programmatic interest within the Heavy Ion Fusion (HIF) Program to explore alternative architectures in the beam injection systems that use the merging of small, bright beams. An ion gun was designed and built for these experiments. Results of average current density yield () at different operating conditions are presented for K+ and Cs+ contact ionization sources and potassium aluminum silicate sources. Maximum values for a K+ beam of ~90 mA/cm2 were observed in 2.3 μs pulses. Measurements of beam intensity profiles and emittances are included. Measurements of neutral particle desorption are presented at different operating conditions which lead to a better understanding of the underlying atomic diffusion processes that determine the lifetime of the emitter. Estimates of diffusion times consistent with measurements are presented, as well as estimates of maximum repetition rates achievable. Diverse studies performed on the composition and preparation of alkali aluminosilicate ion sources are also presented. In addition, this work includes preliminary work carried out exploring the viability of an argon plasma ion source and a bismuth metal vapor vacuum arc (MEVVA) ion source. For the former ion source, fast rise-times (~ 1 μs), high current densities (~ 100 mA/cm+) and low operating pressures (< 2 mtorr) were verified. For the latter, high but acceptable levels of beam emittance were measured (εn ≤ 0.006 π· mm · mrad) although measured currents differed from the desired ones (I ~ 5mA) by about a factor of 10.

  16. Studies in High Current Density Ion Sources for Heavy Ion Fusion Applications

    International Nuclear Information System (INIS)

    Chacon-Golcher, E.

    2002-01-01

    This dissertation develops diverse research on small (diameter ∼ few mm), high current density (J ∼ several tens of mA/cm 2 ) heavy ion sources. The research has been developed in the context of a programmatic interest within the Heavy Ion Fusion (HIF) Program to explore alternative architectures in the beam injection systems that use the merging of small, bright beams. An ion gun was designed and built for these experiments. Results of average current density yield ( ) at different operating conditions are presented for K + and Cs + contact ionization sources and potassium aluminum silicate sources. Maximum values for a K + beam of ∼90 mA/cm 2 were observed in 2.3 (micro)s pulses. Measurements of beam intensity profiles and emittances are included. Measurements of neutral particle desorption are presented at different operating conditions which lead to a better understanding of the underlying atomic diffusion processes that determine the lifetime of the emitter. Estimates of diffusion times consistent with measurements are presented, as well as estimates of maximum repetition rates achievable. Diverse studies performed on the composition and preparation of alkali aluminosilicate ion sources are also presented. In addition, this work includes preliminary work carried out exploring the viability of an argon plasma ion source and a bismuth metal vapor vacuum arc (MEVVA) ion source. For the former ion source, fast rise-times (∼ 1 (micro)s), high current densities (∼ 100 mA/cm 2 ) and low operating pressures ( e psilon) n (le) 0.006 π mm · mrad) although measured currents differed from the desired ones (I ∼ 5mA) by about a factor of 10

  17. Interaction of energetic ions with high-density plasmas

    International Nuclear Information System (INIS)

    Gericke, D.O.; Edie, D.; Grinenko, A.; Vorberger, J.

    2010-01-01

    highly compressed matter around the burning fusion core is however strongly increased due to degeneracy of the target electrons. This result implies the need for much larger hot spots than predicted by standard models. Similarly, the range of light ions considered for fast ignition is increased. This makes success of this efficient ICF approach harder to achieve, but already reflects the need for larger hot spots due to the larger spread of the α-particles heating. Acknowledgements: This work is funded by the Engineering and Physical Sciences Research Council of the UK.

  18. Towards high-density matter with relativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Nagamiya, Shoji.

    1990-04-01

    Recent progress in nucleus-nucleus collisions at BNL and CERN suggests a hint that the formation of high-density nuclear matter could be possible with relativistic heavy-ion beams. What is the maximum density that can be achieved by heavy-ion collisions? Are there data which show evidence or hints on the formation of high density matter? Why is the research of high-density interesting? How about the future possibilities on this subject? These points are discussed. (author)

  19. Fabrication and demonstration of high energy density lithium ion microbatteries

    Science.gov (United States)

    Sun, Ke

    density on a limited footprint area. In chapter 4, Li-ion batteries based on the LiMn2O4-TiP 2O7 couple are manufactured on flexible paper substrates; where the use of light-weight paper substrates significantly increase the gravimetric energy density of this electrode couple as compared to traditional metal current collectors. In chapter 5, a novel nanowire growth mechanism will be explored to grow interdigitated metal oxide nanowire micro battery electrodes. The growth kinetics of this mechanism is systematically studied to understand how to optimize the growth process to produce electrodes with improved electrochemical properties.

  20. Toward Low-Cost, High-Energy Density, and High-Power Density Lithium-Ion Batteries

    Science.gov (United States)

    Li, Jianlin; Du, Zhijia; Ruther, Rose E.; AN, Seong Jin; David, Lamuel Abraham; Hays, Kevin; Wood, Marissa; Phillip, Nathan D.; Sheng, Yangping; Mao, Chengyu; Kalnaus, Sergiy; Daniel, Claus; Wood, David L.

    2017-09-01

    Reducing cost and increasing energy density are two barriers for widespread application of lithium-ion batteries in electric vehicles. Although the cost of electric vehicle batteries has been reduced by 70% from 2008 to 2015, the current battery pack cost (268/kWh in 2015) is still >2 times what the USABC targets (125/kWh). Even though many advancements in cell chemistry have been realized since the lithium-ion battery was first commercialized in 1991, few major breakthroughs have occurred in the past decade. Therefore, future cost reduction will rely on cell manufacturing and broader market acceptance. This article discusses three major aspects for cost reduction: (1) quality control to minimize scrap rate in cell manufacturing; (2) novel electrode processing and engineering to reduce processing cost and increase energy density and throughputs; and (3) material development and optimization for lithium-ion batteries with high-energy density. Insights on increasing energy and power densities of lithium-ion batteries are also addressed.

  1. Nanomaterials Enabled High Energy and Power Density Li-ion Batteries, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — There is a need for high energy (~ 200 Wh/kg) and high power (> 500 W/kg) density rechargeable Li-ion batteries that are safe and reliable for several space and...

  2. High Energy Density Solid State Li-ion Battery with Enhanced Safety, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop an all solid state Li-ion battery which is capable of delivering high energy density, combined with high safety over a wide operating...

  3. High dislocation density structures and hardening produced by high fluency pulsed-ion-beam implantation

    International Nuclear Information System (INIS)

    Sharkeev, Yu.P.; Didenko, A.N.; Kozlov, E.V.

    1994-01-01

    The paper presents a review of experimental data on the ''long-range effect'' (a change in dislocation structure and in physicomechanical properties at distances considerably greater than the ion range value in ion-implanted metallic materials and semiconductors). Our results of electron microscopy studies of high density dislocation structure in ion-implanted metallic materials with different initial states are given. It has been shown that the nature of the dislocation structure and its quantitative characteristics in the implanted metals and alloys depend on the target initial state, the ion type and energy and the retained dose. The data obtained by different workers are in good agreement both with our results and with each other as well as with the results of investigation of macroscopic characteristics (wear resistance and microhardness). It has been established that the ''long-range effect'' occurs in metallic materials with a low yield point or high plasticity level and with little dislocation density in their initial state prior to ion implantation. ((orig.))

  4. Highly Oriented Graphene Sponge Electrode for Ultra High Energy Density Lithium Ion Hybrid Capacitors.

    Science.gov (United States)

    Ahn, Wook; Lee, Dong Un; Li, Ge; Feng, Kun; Wang, Xiaolei; Yu, Aiping; Lui, Gregory; Chen, Zhongwei

    2016-09-28

    Highly oriented rGO sponge (HOG) can be easily synthesized as an effective anode for application in high-capacity lithium ion hybrid capacitors. X-ray diffraction and morphological analyses show that successfully exfoliated rGO sponge on average consists of 4.2 graphene sheets, maintaining its three-dimensional structure with highly oriented morphology even after the thermal reduction procedure. Lithium-ion hybrid capacitors (LIC) are fabricated in this study based on a unique cell configuration which completely eliminates the predoping process of lithium ions. The full-cell LIC consisting of AC/HOG-Li configuration has resulted in remarkably high energy densities of 231.7 and 131.9 Wh kg(-1) obtained at 57 W kg(-1) and 2.8 kW kg(-1). This excellent performance is attributed to the lithium ion diffusivity related to the intercalation reaction of AC/HOG-Li which is 3.6 times higher that of AC/CG-Li. This unique cell design and configuration of LIC presented in this study using HOG as an effective anode is an unprecedented example of performance enhancement and improved energy density of LIC through successful increase in cell operation voltage window.

  5. U.S. Heavy Ion Beam Research for High Energy Density Physics Applications and Fusion

    International Nuclear Information System (INIS)

    Davidson, R.C.; Logan, B.G.; Barnard, J.J.; Bieniosek, F.M.; Briggs, R.J.

    2005-01-01

    Key scientific results from recent experiments, modeling tools, and heavy ion accelerator research are summarized that explore ways to investigate the properties of high energy density matter in heavy-ion-driven targets, in particular, strongly-coupled plasmas at 0.01 to 0.1 times solid density for studies of warm dense matter, which is a frontier area in high energy density physics. Pursuit of these near-term objectives has resulted in many innovations that will ultimately benefit heavy ion inertial fusion energy. These include: neutralized ion beam compression and focusing, which hold the promise of greatly improving the stage between the accelerator and the target chamber in a fusion power plant; and the Pulse Line Ion Accelerator (PLIA), which may lead to compact, low-cost modular linac drivers

  6. Generation of Ta ions at high laser-power densities

    Czech Academy of Sciences Publication Activity Database

    Láska, Leoš; Jungwirth, Karel; Králiková, Božena; Krása, Josef; Pfeifer, Miroslav; Rohlena, Karel; Skála, Jiří; Ullschmied, Jiří; Badziak, J.; Parys, P.; Wolowski, J.; Woryna, E.

    2002-01-01

    Roč. 52, Suppl. D (2002), s. D283-D291 ISSN 0011-4626. [Plasma Physics and Technology. Prague, 10.06.2002-13.06.2002] Institutional research plan: CEZ:AV0Z1010921 Keywords : laser produced plasma * multiple charged Ta ions Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.311, year: 2002

  7. Recent US advances in ion-beam-driven high energy density physics and heavy ion fusion

    International Nuclear Information System (INIS)

    Logan, B.G.; Bieniosek, F.M.; Celata, C.M.; Coleman, J.; Greenway, W.; Henestroza, E.; Kwan, J.W.; Lee, E.P.; Leitner, M.; Roy, P.K.; Seidl, P.A.; Vay, J.-L.; Waldron, W.L.; Yu, S.S.; Barnard, J.J.; Cohen, R.H.; Friedman, A.; Grote, D.P.; Kireeff Covo, M.; Molvik, A.W.; Lund, S.M.; Meier, W.R.; Sharp, W.; Davidson, R.C.; Efthimion, P.C.; Gilson, E.P.; Grisham, L.; Kaganovich, I.D.; Qin, H.; Sefkow, A.B.; Startsev, E.A.; Welch, D.; Olson, C.

    2007-01-01

    During the past two years, significant experimental and theoretical progress has been made in the US heavy ion fusion science program in longitudinal beam compression, ion-beam-driven warm dense matter, beam acceleration, high brightness beam transport, and advanced theory and numerical simulations. Innovations in longitudinal compression of intense ion beams by >50X propagating through background plasma enable initial beam target experiments in warm dense matter to begin within the next two years. We are assessing how these new techniques might apply to heavy ion fusion drivers for inertial fusion energy

  8. A Quasi-Solid-State Sodium-Ion Capacitor with High Energy Density.

    Science.gov (United States)

    Wang, Faxing; Wang, Xiaowei; Chang, Zheng; Wu, Xiongwei; Liu, Xiang; Fu, Lijun; Zhu, Yusong; Wu, Yuping; Huang, Wei

    2015-11-18

    A quasi-solid-state sodium-ion capacitor is demonstrated with nanoporous disordered carbon and macroporous graphene as the negative and positive electrodes, respectively, using a sodium-ion-conducting gel polymer electrolyte. It can operate at a cell voltage as high as 4.2 V with an energy density of record high 168 W h kg(-1). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Modification of high density polyethylene by gold implantation using different ion energies

    Energy Technology Data Exchange (ETDEWEB)

    Nenadović, M.; Potočnik, J. [INS Vinca, Laboratory of Atomic Physics, University of Belgrade, Mike Alasa 12–14, 11001 Belgrade (Serbia); Mitrić, M. [INS Vinca, Condensed Matter Physics Laboratory, University of Belgrade, Mike Alasa 12–14, 11001 Belgrade (Serbia); Štrbac, S. [ICTM Institute of Electrochemistry, University of Belgrade, Njegoseva 12, 11001 Belgrade (Serbia); Rakočević, Z., E-mail: zlatkora@vinca.rs [INS Vinca, Laboratory of Atomic Physics, University of Belgrade, Mike Alasa 12–14, 11001 Belgrade (Serbia)

    2013-11-01

    High density polyethylene (HDPE) samples were modified by Au{sup +} ion implantation at a dose of 5 × 10{sup 15} ions cm{sup −2}, using energies of 50, 100, 150 and 200 keV. The existence of implanted gold in the near-surface region of HDPE samples was confirmed by X-ray diffraction analysis. Surface roughness and Power Spectral Density analyses based on Atomic Force Microscopy (AFM) images of the surface topography revealed that the mechanism of HDPE modification during gold ion implantation depended on the energy of gold ions. Histograms obtained from phase AFM images indicated a qualitative change in the chemical composition of the surface during implantation with gold ions with different energies. Depth profiles obtained experimentally from cross-sectional Force Modulation Microscopy images and ones obtained from a theoretical simulation are in agreement for gold ions energies lower than 100 keV. The deviation that was observed for higher energies of the gold ions is explained by carbon precipitation in the near surface region of the HDPE, which prevented the penetration of gold ions further into the depth of the sample. - Highlights: • HDPE was implanted by Au{sup +} ions using energies of 50, 100, 150 and 200 keV. • Surface composition was analyzed from phase AFM images. • FMM depth profiles are in agreement with theoretical ones for energies up to 100 keV. • A deviation is observed for higher gold ion energies.

  10. Modification of high density polyethylene by gold implantation using different ion energies

    International Nuclear Information System (INIS)

    Nenadović, M.; Potočnik, J.; Mitrić, M.; Štrbac, S.; Rakočević, Z.

    2013-01-01

    High density polyethylene (HDPE) samples were modified by Au + ion implantation at a dose of 5 × 10 15 ions cm −2 , using energies of 50, 100, 150 and 200 keV. The existence of implanted gold in the near-surface region of HDPE samples was confirmed by X-ray diffraction analysis. Surface roughness and Power Spectral Density analyses based on Atomic Force Microscopy (AFM) images of the surface topography revealed that the mechanism of HDPE modification during gold ion implantation depended on the energy of gold ions. Histograms obtained from phase AFM images indicated a qualitative change in the chemical composition of the surface during implantation with gold ions with different energies. Depth profiles obtained experimentally from cross-sectional Force Modulation Microscopy images and ones obtained from a theoretical simulation are in agreement for gold ions energies lower than 100 keV. The deviation that was observed for higher energies of the gold ions is explained by carbon precipitation in the near surface region of the HDPE, which prevented the penetration of gold ions further into the depth of the sample. - Highlights: • HDPE was implanted by Au + ions using energies of 50, 100, 150 and 200 keV. • Surface composition was analyzed from phase AFM images. • FMM depth profiles are in agreement with theoretical ones for energies up to 100 keV. • A deviation is observed for higher gold ion energies

  11. Negative Ion Density Fronts

    International Nuclear Information System (INIS)

    Igor Kaganovich

    2000-01-01

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas

  12. Extraction Compression and Acceleration of High Line Charge Density Ion Beams

    CERN Document Server

    Henestroza, Enrique; Grote, D P; Peters, Craig; Yu, Simon

    2005-01-01

    HEDP applications require high line charge density ion beams. An efficient method to obtain this type of beams is to extract a long pulse, high current beam from a gun at high energy, and let the beam pass through a decelerating field to compress it. The low energy beam bunch is loaded into a solenoid and matched to a Brillouin flow. The Brillouin equilibrium is independent of the energy if the relationship between the beam size (a), solenoid magnetic field strength (B) and line charge density is such that (Ba)2

  13. Studies on the production of high energy densities in matter by intense heavy-ion beams

    International Nuclear Information System (INIS)

    Jacoby, J.

    1989-08-01

    In the framework of the present thesis the interaction of an intense heavy-ion beam with a small, but macroscopical amount of matter is studied. Thereby high energy densities in the target matter are produced. For this experiment it was for the first time possible to heat matter with ion beams from conventional heavy-ion accelerators up to plasma conditions. A KR + -ion beam was first accelerated with the heavy-ion accelerator MAXILAC to 45 keV/u and then focussed by a fine-focusing lens to a closed xenon gas target. The light emitted from the target was space- and time resolved taken up by a spectrometer as well as by a streak and CCD camera. Thereby the radial development of the plasma and the penetration behaviour of the ion beam was observed. The free electron density of the plasma was determined from the Stark broadening of emission lines (n e ≅ 4x10 16 cm -3 ). The temperature could be determined by different methods (shock-wave velocity, degree of ionization, line ratios). The electron temperature amounted in the center of the pipe to kT ≅ 0.75 eV. For the opacity of the target by which the emitted light power is determined under the assumption of the two-dimensional model (equilibrium between emitted and absorbed energy) the value κ p ≅ 7700 cm 2 /g resulted. (orig./HSI) [de

  14. Studies on the production of high energy density in matter with intense heavy-ion beams

    International Nuclear Information System (INIS)

    Jacoby, J.

    1989-01-01

    In the framework of the present thesis the interaction of an intense heavy-ion beam with a small, but macroscopic, amount of matter is studied. Thereby high energy densities are produced in the target matter. For this experiment it was for the first time possible to heat matter with ion beams from conventional heavy-ion accelerators up to plasma conditions. A Kr + ion beam was first accelerated with the heavy-ion accelerator MAXILAC to 45 keV/u and then focused by a fine-focusing lens on a closed xenon gas target. The light emitted from the target was space- and time-resolved taken up with a spectrometer as well a streak and CCD camera. Thereby the radial development of the plasma and the penetration behaviour of the ion beam were consecuted. The free-electron density of the plasma was determined from the Stark-broadening of emission lines (n e ≅ 4x10 16 cm -3 ). The electron temperature amounted in the center of the pipelet kT ≅ 0.75 eV. (orig./HSI) [de

  15. High energy density in matter produced by heavy ion beams. Annual report 1993

    International Nuclear Information System (INIS)

    1994-06-01

    The experimental activities at GSI were concentrated on the progress in beam-plasma interaction experiments of heavy ion with ionized matter, plasma -lens forming devices, intense beam at high temperature experimental area, and charge exchange collisions of ions. The development to higher intensities and phase space densities during 1993 for the SIS and the ESR is recorded. The possibility of studying of funneling of two beams in a two-beam RFQ is studied. Specific results are presented with respect to inertial confinement fusion (ICF). The problem of ion stopping in plasma and pumping X-ray lasers with heavy ion beams are discussed. Various contributions deal with dense plasma effects, shocks and opacity. (HP)

  16. Achieving high baryon densities in the fragmentation regions in heavy ion collisions at top RHIC energy

    International Nuclear Information System (INIS)

    Li, Ming; Kapusta, Joseph I.

    2017-01-01

    Heavy ion collisions at extremely high energy, such as the top energy at RHIC, exhibit the property of transparency where there is a clear separation between the almost net-baryon-free central rapidity region and the net-baryon-rich fragmentation region. We calculate the net-baryon rapidity loss and the nuclear excitation energy using the energy-momentum tensor obtained from the McLerran-Venugopalan model. Nuclear compression during the collision is further estimated using a simple space-time picture. The results show that extremely high baryon densities, about twenty times larger than the normal nuclear density, can be achieved in the fragmentation regions. (paper)

  17. High current density ion beam obtained by a transition to a highly focused state in extremely low-energy region

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Y., E-mail: y.hirano@aist.go.jp, E-mail: hirano.yoichi@phys.cst.nihon-u.ac.jp [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); College of Science and Technologies, Nihon University, Chiyodaku, Tokyo 101-0897 (Japan); Kiyama, S.; Koguchi, H. [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Fujiwara, Y.; Sakakita, H. [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki 305-8577 (Japan)

    2015-11-15

    A high current density (≈3 mA/cm{sup 2}) hydrogen ion beam source operating in an extremely low-energy region (E{sub ib} ≈ 150–200 eV) has been realized by using a transition to a highly focused state, where the beam is extracted from the ion source chamber through three concave electrodes with nominal focal lengths of ≈350 mm. The transition occurs when the beam energy exceeds a threshold value between 145 and 170 eV. Low-level hysteresis is observed in the transition when E{sub ib} is being reduced. The radial profiles of the ion beam current density and the low temperature ion current density can be obtained separately using a Faraday cup with a grid in front. The measured profiles confirm that more than a half of the extracted beam ions reaches the target plate with a good focusing profile with a full width at half maximum of ≈3 cm. Estimation of the particle balances in beam ions, the slow ions, and the electrons indicates the possibility that the secondary electron emission from the target plate and electron impact ionization of hydrogen may play roles as particle sources in this extremely low-energy beam after the compensation of beam ion space charge.

  18. Formation and disintegration of high-density nuclear matter in heavy-ion collisions

    International Nuclear Information System (INIS)

    Kitazoe, Yasuhiro; Matsuoka, Kazuo; Sano, Mitsuo

    1976-01-01

    The formation of high-density nuclear matter which may be expected to be attained in high-energy heavy-ion collisions and the subsequent disintegration of dense matter are investigated by means of the hydrodynamics. Head-on collisions of identical nuclei are considered in the nonrelativistic approximation. The compressed density cannot exceed 4 times of the normal one so long as the freedom of only nucleons is considered, and can become higher than 4 times when other freedoms such as the productions of mesons and also nucleon isobars are additionally taken into account. The angular distributions for ejected particles predominate both forwards and backwards at low collision energies, corresponding to the formation of nuclear density less than 2 times of the normal density and become isotropic at the point of 2 times of the normal one. As the collision energy increases further, lateral ejection is intensified gradually. (auth.)

  19. Unique aqueous Li-ion/sulfur chemistry with high energy density and reversibility.

    Science.gov (United States)

    Yang, Chongyin; Suo, Liumin; Borodin, Oleg; Wang, Fei; Sun, Wei; Gao, Tao; Fan, Xiulin; Hou, Singyuk; Ma, Zhaohui; Amine, Khalil; Xu, Kang; Wang, Chunsheng

    2017-06-13

    Leveraging the most recent success in expanding the electrochemical stability window of aqueous electrolytes, in this work we create a unique Li-ion/sulfur chemistry of both high energy density and safety. We show that in the superconcentrated aqueous electrolyte, lithiation of sulfur experiences phase change from a high-order polysulfide to low-order polysulfides through solid-liquid two-phase reaction pathway, where the liquid polysulfide phase in the sulfide electrode is thermodynamically phase-separated from the superconcentrated aqueous electrolyte. The sulfur with solid-liquid two-phase exhibits a reversible capacity of 1,327 mAh/(g of S), along with fast reaction kinetics and negligible polysulfide dissolution. By coupling a sulfur anode with different Li-ion cathode materials, the aqueous Li-ion/sulfur full cell delivers record-high energy densities up to 200 Wh/(kg of total electrode mass) for >1,000 cycles at ∼100% coulombic efficiency. These performances already approach that of commercial lithium-ion batteries (LIBs) using a nonaqueous electrolyte, along with intrinsic safety not possessed by the latter. The excellent performance of this aqueous battery chemistry significantly promotes the practical possibility of aqueous LIBs in large-format applications.

  20. High Energy Density Li-Ion Batteries Designed for Low Temperature Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The state-of-the-art Li-ion batteries do not fully meet the energy density, power density and safety requirements specified by NASA for future exploration missions....

  1. Flexible Aqueous Li-Ion Battery with High Energy and Power Densities.

    Science.gov (United States)

    Yang, Chongyin; Ji, Xiao; Fan, Xiulin; Gao, Tao; Suo, Liumin; Wang, Fei; Sun, Wei; Chen, Ji; Chen, Long; Han, Fudong; Miao, Ling; Xu, Kang; Gerasopoulos, Konstantinos; Wang, Chunsheng

    2017-11-01

    A flexible and wearable aqueous symmetrical lithium-ion battery is developed using a single LiVPO 4 F material as both cathode and anode in a "water-in-salt" gel polymer electrolyte. The symmetric lithium-ion chemistry exhibits high energy and power density and long cycle life, due to the formation of a robust solid electrolyte interphase consisting of Li 2 CO 3 -LiF, which enables fast Li-ion transport. Energy densities of 141 Wh kg -1 , power densities of 20 600 W kg -1 , and output voltage of 2.4 V can be delivered during >4000 cycles, which is far superior to reported aqueous energy storage devices at the same power level. Moreover, the full cell shows unprecedented tolerance to mechanical stress such as bending and cutting, where it not only does not catastrophically fail, as most nonaqueous cells would, but also maintains cell performance and continues to operate in ambient environment, a unique feature apparently derived from the high stability of the "water-in-salt" gel polymer electrolyte. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. High energy density in matter produced by heavy ion beams. Annual report 1987

    International Nuclear Information System (INIS)

    1988-08-01

    Research activities presented in this annual report were carried out in 1987 in the framework of the government-funded program 'High Energy Density in Matter Produced by Heavy Ion Beams'. It addresses fundamental problems of the generation and investigation of hot dense matter. Its initial motivation and its ultimate goal is the question whether inertial confinement can be achieved by intense heavy ion beams. The new accelerator facility SIS/ESR now under construction at GSI will provide an excellent potential for research in this field. The construction work at the new validity is on schedule. The building construction is near completion and the SIS accelerator will have its first beam at the beginning of next year. First experiments at lower intensity will start in summer 1989 and the full program will run after the cooler and storage ring ESR has got operational. Accordingly, the planning and the preparation of the high energy density experiments at this unique facility was an essential part of the activities last year. In this funding period emphasis was given to the experimental activities at the existing accelerator. In addition to a number of accelerator-oriented and instrumental developments, an experiment on beam-plasma interaction had first exciting results, a significant increase of the stopping power for heavy ions in plasma was measured. Other important activities were the investigation of dielectronic recombination of highly charged ions, spectroscopic investigations aiming at the pumping of short wavelength lasers by heavy ion beams and a crossed beam experiment for the determination of Bi + + Bi + ionization cross sections. As in previous years theoretical work an space-charge dominated beam dynamics as well as on hydrodynamics of dense plasmas, radiation transport and beam plasma interaction was continued, thus providing a basis for the future experiments. (orig.)

  3. Line profiles of hydrogenic ions from high-temperature and high-density plasmas

    International Nuclear Information System (INIS)

    Hou Qing; Li Jianming

    1991-01-01

    Applying the Hooper's first-order theory, the authors calculate the static micro-electric field distributions in plasmas containing various multiply-charged ions. The influences of the impurity concentrations on the micro electric field distributions and on the Lyman profiles (n→1) from hydrogenic ions are analysed. Based on the optical-thin line profiles, the radiation transfer equation in sphere plasmas with various optical depths is solved. The results confirm that the opacity-broadening of the line profiles has almost no effect on the separation of Lyman β splitted peaks. Such separation is determined by electric field at which the static micro-electric field distribution has a maximum. The separation can be utilized for spatially resolved and temporally resolved density diagnostic of fusion plasmas

  4. Probing the nuclear matter at high baryon and isospin density with heavy ion collisions

    International Nuclear Information System (INIS)

    Di Toro, M.; Colonna, M.; Ferini, G.

    2010-01-01

    Heavy Ion Collisions (HIC) represent a unique tool to probe the in-medium nuclear interaction in regions away from saturation. High Energy Collisions are studied in order to access nuclear matter properties at high density. Particular attention is devoted to the selection of observables sensitive to the poorly known symmetry energy at high baryon density, of large fundamental interest, even for the astrophysics implications. Using fully consistent covariant transport simulations built on effective field theories we are testing isospin observables ranging from nucleon/cluster emissions, collective flows (in particular the elliptic, squeeze out, part) and meson production. The possibility to shed light on the controversial neutron/proton effective mass splitting in asymmetric matter is also stressed. The "symmetry" repulsion at high baryon density will also lead to an "earlier" hadron-deconfinement transition in n-rich matter. The phase transition of hadronic to quark matter at high baryon and isospin density is analyzed. Nonlinear relativistic mean field models are used to describe hadronic matter, and the MIT bag model is adopted for quark matter. The boundaries of the mixed phase and the related critical points for symmetric and asymmetric matter are obtained. Isospin effects appear to be rather significant. The binodal transition line of the (T,ρ B ) diagram is lowered in a region accessible to heavy ion collisions in the energy range of the new planned FAIR/NICA facilities. Some observable effects of the mixed phase are suggested, in particular a neutron distillation mechanism. Theoretically a very important problem appears to be the suitable treatment of the isovector part of the interaction in effective QCD lagrangian approaches. (author)

  5. Electrodeposition of high-density lithium vanadate nanowires for lithium-ion battery

    Science.gov (United States)

    Hua, Kang; Li, Xiujuan; Fang, Dong; Yi, Jianhong; Bao, Rui; Luo, Zhiping

    2018-07-01

    Lithium vanadate nanowires have been electrodeposited onto a titanium (Ti) foil by a direct current electrodeposition without template. The morphology, crystal structure, and the effects of deposition voltage, temperature and time on the prepared samples were tested and presented. The as-prepared lithium vanadate nanowires/Ti composite can be used as electrode for lithium-ion battery. Electrochemical measurements showed that the electrode displayed a specific discharge capacitance as high as 235.1 mAh g-1 after 100 cycles at a current density of 30 mA g-1. This research provides a new pathway to explore high tap density vanadates nanowires on metals with enhanced electrochemical performance.

  6. Measurements of Ion Stopping around the Bragg Peak in High-Energy-Density Plasmas

    Science.gov (United States)

    Frenje, Johan

    2015-11-01

    Over the last few decades, ion stopping in weakly- to strongly-coupled High-Energy-Density (HED) plasmas has been subject to extensive analytical and numerical studies, but only a limited set of experimental data exists to check the validity of these theories. Most of these experiments also did not probe the detailed characteristics of the Bragg peak (peak ion stopping) where the ion velocity is similar to the average thermal electron velocity. To the best of our knowledge, only one exploratory attempt to do this was conducted by Hicks et al., who were able to describe qualitatively the behavior of the Bragg peak for one plasma condition. The work described in this presentation makes significant advances over previous experimental efforts by quantitatively assessing the characteristics of the ion stopping, ranging from low-velocity stopping, through the Bragg peak, to high-velocity stopping for different HED plasma conditions. This was achieved by measuring the energy loss of DD-tritons, D3He-alphas, DD-protons and D3He-protons, with distinctly different velocities, and the results indicate that the stopping power varies strongly with Te and ne. This effort represents the first experimental test of state-of-art plasma-stopping-power theories around the Bragg peak, which is an important first step in our efforts of getting a fundamental understanding of DT-alpha stopping in HED plasmas, a prerequisite for understanding ignition margins in various implosion designs with varying hot spot areal density at the National Ignition Facility. The work described here was performed in part at the LLE National Laser User's Facility (NLUF), and was supported in part by US DOE (Grant No. DE-FG03- 03SF22691), LLNL (subcontract Grant No. B504974) and LLE (subcontract Grant No. 412160-001G).

  7. Swift heavy ion induced single event upsets in high density UV-EPROM's

    Energy Technology Data Exchange (ETDEWEB)

    Dahiwale, S.S. [Department of Physics, University of Pune, Pune 7 (India); Shinde, N.S. [Department of Chemical Engineering, Mie University (Japan); Kanjilal, D. [Inter University Accelerator Center, New Delhi (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 7 (India); Dhole, S.D. [Department of Physics, University of Pune, Pune 7 (India)], E-mail: sanjay@physics.unipune.ernet.in

    2008-04-15

    A few high density UV-EPROM's (32Kb x 8) were irradiated with 5.41 MeV energy {alpha}-particles with fluences from 10{sup 4} to 10{sup 8} alphas/cm{sup 2} and 100 MeV nickel, iodine and silver ions for low fluences between 5 x 10{sup 7} and 10{sup 8} ions/cm{sup 2}. The energy and ion species was selected on the basis of predicted threshold values of linear energy transfer (LET) in silicon. The program which was stored in the memory found to be changed from 0 to 1 and 1 to 0 state, respectively. On the basis of changed states, the cross-sections ({sigma}) were calculated to investigate the single event effects/upsets. No upset was observed in case of {alpha}-particle since it has very low LET, but the SEU cross-section found to be more in case of Iodine i.e. 2.29 x 10{sup -3} cm{sup 2} than that of nickel, 2.12 x 10{sup -3} cm{sup 2} and silver, 2.26 x 10{sup -3}. This mainly attributes that LET for iodine is more as compared to silver and nickel ions, which deposits large amount of energy near the sensitive node of memory cell in the form of electron-hole pairs required to change the state. These measured SEU cross-section were also compared with theoretically predicted values along with the Weibull distribution fit to the ion induced experimental SEU data. The theoretical predicted SEU cross-section 3.27 x 10{sup -3} cm{sup 2} found to be in good agreement with the measured SEU cross-section.

  8. Achieving High-Energy-High-Power Density in a Flexible Quasi-Solid-State Sodium Ion Capacitor.

    Science.gov (United States)

    Li, Hongsen; Peng, Lele; Zhu, Yue; Zhang, Xiaogang; Yu, Guihua

    2016-09-14

    Simultaneous integration of high-energy output with high-power delivery is a major challenge for electrochemical energy storage systems, limiting dual fine attributes on a device. We introduce a quasi-solid-state sodium ion capacitor (NIC) based on a battery type urchin-like Na2Ti3O7 anode and a capacitor type peanut shell derived carbon cathode, using a sodium ion conducting gel polymer as electrolyte, achieving high-energy-high-power characteristics in solid state. Energy densities can reach 111.2 Wh kg(-1) at power density of 800 W kg(-1), and 33.2 Wh kg(-1) at power density of 11200 W kg(-1), which are among the best reported state-of-the-art NICs. The designed device also exhibits long-term cycling stability over 3000 cycles with capacity retention ∼86%. Furthermore, we demonstrate the assembly of a highly flexible quasi-solid-state NIC and it shows no obvious capacity loss under different bending conditions.

  9. High Energy Density Li-ion Cells for EV’s Based on Novel, High Voltage Cathode Material Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kepler, Keith [Farasis Energy Inc; Slater, Michael [Farasis Energy Inc

    2018-03-14

    This Li-ion cell technology development project had three objectives: to develop advanced electrode materials and cell components to enable stable high-voltage operation; to design and demonstrate a Li-ion cell using these materials that meets the PHEV40 performance targets; and to design and demonstrate a Li-ion cell using these materials that meets the EV performance targets. The major challenge to creating stable high energy cells with long cycle life is system integration. Although materials that can give high energy cells are known, stabilizing them towards long-term cycling in the presence of other novel cell components is a major challenge. The major technical barriers addressed by this work include low cathode specific energy, poor electrolyte stability during high voltage operation, and insufficient capacity retention during deep discharge for Si-containing anodes. Through the course of this project, Farasis was able to improve capacity retention of NCM materials for 4.4+ V operation, through both surface treatment and bulk-doping approaches. Other material advances include increased rate capability and of HE-NCM materials through novel synthesis approach, doubling the relative capacity at 1C over materials synthesized using standard methods. Silicon active materials proved challenging throughout the project and ultimately were the limiting factor in the energy density vs. cycle life trade off. By avoiding silicon anodes for the lower energy PHEV design, we manufactured cells with intermediate energy density and long cycle life under high voltage operation for PHEV applications. Cells with high energy density for EV applications were manufactured targeting a 300 Wh/kg design and were able to achieve > 200 cycles.

  10. Collective Focusing of Intense Ion Beam Pulses for High-energy Density Physics Applications

    International Nuclear Information System (INIS)

    Dorf, Mikhail A.; Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.

    2011-01-01

    The collective focusing concept in which a weak magnetic lens provides strong focusing of an intense ion beam pulse carrying a neutralizing electron background is investigated by making use of advanced particle-in-cell simulations and reduced analytical models. The original analysis by Robertson Phys. Rev. Lett. 48, 149 (1982) is extended to the parameter regimes of particular importance for several high-energy density physics applications. The present paper investigates (1) the effects of non-neutral collective focusing in a moderately strong magnetic field; (2) the diamagnetic effects leading to suppression of the applied magnetic field due to the presence of the beam pulse; and (3) the influence of a finite-radius conducting wall surrounding the beam cross-section on beam neutralization. In addition, it is demonstrated that the use of the collective focusing lens can significantly simplify the technical realization of the final focusing of ion beam pulses in the Neutralized Drift Compression Experiment-I (NDCX-I), and the conceptual designs of possible experiments on NDCX-I are investigated by making use of advanced numerical simulations.

  11. Realization of a diamond based high density multi electrode array by means of Deep Ion Beam Lithography

    International Nuclear Information System (INIS)

    Picollo, F.; Battiato, A.; Bernardi, E.; Boarino, L.; Enrico, E.; Forneris, J.; Gatto Monticone, D.; Olivero, P.

    2015-01-01

    In the present work we report about a parallel-processing ion beam fabrication technique whereby high-density sub-superficial graphitic microstructures can be created in diamond. Ion beam implantation is an effective tool for the structural modification of diamond: in particular ion-damaged diamond can be converted into graphite, therefore obtaining an electrically conductive phase embedded in an optically transparent and highly insulating matrix. The proposed fabrication process consists in the combination of Deep Ion Beam Lithography (DIBL) and Focused Ion Beam (FIB) milling. FIB micromachining is employed to define micro-apertures in the contact masks consisting of thin (<10 μm) deposited metal layers through which ions are implanted in the sample. A prototypical single-cell biosensor was realized with the above described technique. The biosensor has 16 independent electrodes converging inside a circular area of 20 μm diameter (typical neuroendocrine cells size) for the simultaneous recording of amperometric signals

  12. Nernst-Planck modeling of multicomponent ion transport in a Nafion membrane at high current density

    NARCIS (Netherlands)

    Moshtari Khah, S.; Oppers, N.A.W.; de Groot, M.T.; Keurentjes, J.T.F.; Schouten, J.C.; van der Schaaf, J.

    A mathematical model of multicomponent ion transport through a cation-exchange membrane is developed based on the Nernst–Planck equation. A correlation for the non-linear potential gradient is derived from current density relation with fluxes. The boundary conditions are determined with the Donnan

  13. Swift heavy ion irradiation effects on carbonyl and trans-vinylene groups in high and low density polyethylene

    International Nuclear Information System (INIS)

    Grosso, M.F. del; Chappa, V.C.; Arbeitman, C.R.; Garcia Bermudez, G.; Behar, M.

    2009-01-01

    In this work, we have studied the effects of swift heavy ion irradiation on the creation of new functional groups in high and low density polyethylene (HDPE and LDPE). Polymers were irradiated with different ions (6.77 MeV He and 47 MeV Li) and fluences. The induced changes were analyzed by Fourier transform infrared (FTIR) spectroscopy. Creation and damage cross sections for some groups were compared for two different types of PE.

  14. Swift heavy ion irradiation effects on carbonyl and trans-vinylene groups in high and low density polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Grosso, M.F. del, E-mail: delgrosso@tandar.cnea.gov.a [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); Chappa, V.C. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); CONICET (Argentina); Arbeitman, C.R. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); Garcia Bermudez, G. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); CONICET (Argentina); Escuela de Ciencia y Tecnologia, UNSAM (Argentina); Behar, M. [Instituto de Fisica, UFRGS, Porto Alegre (Brazil)

    2009-10-01

    In this work, we have studied the effects of swift heavy ion irradiation on the creation of new functional groups in high and low density polyethylene (HDPE and LDPE). Polymers were irradiated with different ions (6.77 MeV He and 47 MeV Li) and fluences. The induced changes were analyzed by Fourier transform infrared (FTIR) spectroscopy. Creation and damage cross sections for some groups were compared for two different types of PE.

  15. Flexible Aqueous Lithium-Ion Battery with High Safety and Large Volumetric Energy Density.

    Science.gov (United States)

    Dong, Xiaoli; Chen, Long; Su, Xiuli; Wang, Yonggang; Xia, Yongyao

    2016-06-20

    A flexible and wearable aqueous lithium-ion battery is introduced based on spinel Li1.1 Mn2 O4 cathode and a carbon-coated NASICON-type LiTi2 (PO4 )3 anode (NASICON=sodium-ion super ionic conductor). Energy densities of 63 Wh kg(-1) or 124 mWh cm(-3) and power densities of 3 275 W kg(-1) or 11.1 W cm(-3) can be obtained, which are seven times larger than the largest reported till now. The full cell can keep its capacity without significant loss under different bending states, which shows excellent flexibility. Furthermore, two such flexible cells in series with an operation voltage of 4 V can be compatible with current nonaqueous Li-ion batteries. Therefore, such a flexible cell can potentially be put into practical applications for wearable electronics. In addition, a self-chargeable unit is realized by integrating a single flexible aqueous Li-ion battery with a commercial flexible solar cell, which may facilitate the long-time outdoor operation of flexible and wearable electronic devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Ion density in ionizing beams

    International Nuclear Information System (INIS)

    Knuyt, G.K.; Callebaut, D.K.

    1978-01-01

    The equations defining the ion density in a non-quasineutral plasma (chasma) are derived for a number of particular cases from the general results obtained in paper 1. Explicit calculations are made for a fairly general class of boundaries: all tri-axial ellipsoids, including cylinders with elliptic cross-section and the plane parallel case. The results are very simple. When the ion production and the beam intensity are constant then the steady state ion space charge is also constant in space, it varies over less than 10% for the various geometries, it may exceed the beam density largely for comparatively high pressures (usually still less than about 10 -3 Torr), it is tabulated for a number of interesting cases and moreover it can be calculated precisely and easily by some simple formulae for which also approximations are elaborated. The total potential is U =-ax 2 -by 2 -cz 2 , a, b and c constants which can be calculated immediately from the space charge density and the geometry; the largest coefficient varies at most over a factor four for various geometries; it is tabulated for a number of interesting cases. (author)

  17. High energy density layered-spinel hybrid cathodes for lithium ion rechargeable batteries

    Energy Technology Data Exchange (ETDEWEB)

    Basu, S., E-mail: sbasumajumder@yahoo.com [Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721 302 (India); Dahiya, P.P.; Akhtar, Mainul [Materials Science Center, Indian Institute of Technology Kharagpur, Kharagpur 721 302 (India); Ray, S.K. [Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721 302 (India); Chang, J.K. [Institute of Materials Science and Engineering, National Central University, Taiwan (China); Majumder, S.B. [Materials Science Center, Indian Institute of Technology Kharagpur, Kharagpur 721 302 (India)

    2016-11-15

    Highlights: • Structural integration of layered domains in spinel matrix of the composite particles. • Highest discharge capacity (275 mAh g{sup −1}) in composite with 30.0 mole% Li{sub 2}MnO{sub 3}. • Reasonably good rate capability of layered-spinel composite cathode. • Capacity fading with cycling is related to cubic to tetragonal structural phase transition. - Abstract: High energy density Li{sub 2}MnO{sub 3} (layered)–LiMn{sub 1.5}Ni{sub 0.5}O{sub 4} (spinel) composite cathodes have been synthesized using auto-combustion route. Rietveld refinements together with the analyses of high resolution transmission electron micrographs confirm the structural integration of Li{sub 2}MnO{sub 3} nano-domains into the LiMn{sub 1.5}Ni{sub 0.5}O{sub 4} matrix of the composite cathodes. The discharge capacity of the composite cathodes are due to the intercalation of Li{sup +} ion in the tetrahedral (8a) and octahedral (16c) sites of the spinel component and also the insertion of Li{sup +} in the freshly prepared MnO{sub 2} lattice, formed after Li{sub 2}O extraction from the Li{sub 2}MnO{sub 3} domains. The capacity fading of the composite cathodes are explained to be due to the layered to spinel transition of the Li{sub 2}MnO{sub 3} component and Li{sup +} insertion into the octahedral site of the spinel lattices which trigger cubic to tetragonal phase transition resulting volume expansion which eventually retard the Li{sup +} intercalation with cycling.

  18. Development of Functional Surfaces on High-Density Polyethylene (HDPE) via Gas-Assisted Etching (GAE) Using Focused Ion Beams.

    Science.gov (United States)

    Sezen, Meltem; Bakan, Feray

    2015-12-01

    Irradiation damage, caused by the use of beams in electron and ion microscopes, leads to undesired physical/chemical material property changes or uncontrollable modification of structures. Particularly, soft matter such as polymers or biological materials is highly susceptible and very much prone to react on electron/ion beam irradiation. Nevertheless, it is possible to turn degradation-dependent physical/chemical changes from negative to positive use when materials are intentionally exposed to beams. Especially, controllable surface modification allows tuning of surface properties for targeted purposes and thus provides the use of ultimate materials and their systems at the micro/nanoscale for creating functional surfaces. In this work, XeF2 and I2 gases were used in the focused ion beam scanning electron microscope instrument in combination with gallium ion etching of high-density polyethylene surfaces with different beam currents and accordingly different gas exposure times resulting at the same ion dose to optimize and develop new polymer surface properties and to create functional polymer surfaces. Alterations in the surface morphologies and surface chemistry due to gas-assisted etching-based nanostructuring with various processing parameters were tracked using high-resolution SEM imaging, complementary energy-dispersive spectroscopic analyses, and atomic force microscopic investigations.

  19. High density nitrogen-vacancy sensing surface created via He{sup +} ion implantation of {sup 12}C diamond

    Energy Technology Data Exchange (ETDEWEB)

    Kleinsasser, Ed E., E-mail: edklein@uw.edu [Department of Electrical Engineering, University of Washington, Seattle, Washington 98195-2500 (United States); Stanfield, Matthew M.; Banks, Jannel K. Q. [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States); Zhu, Zhouyang; Li, Wen-Di [HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen 518000 (China); Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong (China); Acosta, Victor M. [Department of Physics and Astronomy, Center for High Technology Materials, University of New Mexico, Albuquerque, New Mexico 87106 (United States); Watanabe, Hideyuki [Correlated Electronics Group, Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Itoh, Kohei M. [School of Fundamental Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Fu, Kai-Mei C., E-mail: kaimeifu@uw.edu [Department of Electrical Engineering, University of Washington, Seattle, Washington 98195-2500 (United States); Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2016-05-16

    We present a promising method for creating high-density ensembles of nitrogen-vacancy centers with narrow spin-resonances for high-sensitivity magnetic imaging. Practically, narrow spin-resonance linewidths substantially reduce the optical and RF power requirements for ensemble-based sensing. The method combines isotope purified diamond growth, in situ nitrogen doping, and helium ion implantation to realize a 100 nm-thick sensing surface. The obtained 10{sup 17 }cm{sup −3} nitrogen-vacancy density is only a factor of 10 less than the highest densities reported to date, with an observed 200 kHz spin resonance linewidth over 10 times narrower.

  20. Chiral symmetry restoration versus deconfinement in heavy-ion collisions at high baryon density

    Science.gov (United States)

    Bratkovskaya, E. L.; Palmese, A.; Cassing, W.; Seifert, E.; Steinert, T.; Moreau, P.

    2017-07-01

    The effect of the chiral symmetry restoration (CSR) on observables from heavy-ion collisions is studied in the energy range \\sqrt{{s}NN}=3-20 {GeV} within the Parton-Hadron-String Dynamics (PHSD) transport approach. The PHSD includes the deconfinement phase transition as well as essential aspects of CSR in the dense and hot hadronic medium, which are incorporated in the Schwinger mechanism for the hadronic particle production. We adopt different parametrizations of the nuclear equation of state from the non-linear σ - ω model, which enter in the computation of the quark scalar density for the CSR mechanism, in order to estimate the uncertainty in our calculations. For the pion-nucleon Σ-term we adopt Σ π ≈ 45 MeV which corresponds to some ‘world average’. Our systematic studies show that chiral symmetry restoration plays a crucial role in the description of heavy-ion collisions at \\sqrt{{s}NN}=3-20 {GeV}, realizing an increase of the hadronic particle production in the strangeness sector with respect to the non-strange one. We identify particle abundances and rapidity spectra to be suitable probes in order to extract information about CSR, while transverse mass spectra are less sensitive. Our results provide a microscopic explanation for the “horn” structure in the excitation function of the K +/π + ratio: the CSR in the hadronic phase produces the steep increase of this particle ratio up to \\sqrt{{s}NN}≈ 7 {GeV}, while the drop at higher energies is associated to the appearance of a deconfined partonic medium.

  1. Injection of auxiliary electrons for increasing the plasma density in highly charged and high intensity ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Odorici, F., E-mail: fabrizio.odorici@bo.infn.it; Malferrari, L.; Montanari, A. [INFN—Bologna, Viale B. Pichat, 6/2, 40127 Bologna (Italy); Rizzoli, R. [INFN—Bologna, Viale B. Pichat, 6/2, 40127 Bologna (Italy); CNR–Istituto per la Microelettronica ed i Microsistemi, Via Gobetti 101, 40129 Bologna (Italy); Mascali, D.; Castro, G.; Celona, L.; Gammino, S.; Neri, L. [INFN–Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy)

    2016-02-15

    Different electron guns based on cold- or hot-cathode technologies have been developed since 2009 at INFN for operating within ECR plasma chambers as sources of auxiliary electrons, with the aim of boosting the source performances by means of a higher plasma lifetime and density. Their application to microwave discharge ion sources, where plasma is not confined, has required an improvement of the gun design, in order to “screen” the cathode from the plasma particles. Experimental tests carried out on a plasma reactor show a boost of the plasma density, ranging from 10% to 90% when the electron guns are used, as explained by plasma diffusion models.

  2. Injection of auxiliary electrons for increasing the plasma density in highly charged and high intensity ion sources.

    Science.gov (United States)

    Odorici, F; Malferrari, L; Montanari, A; Rizzoli, R; Mascali, D; Castro, G; Celona, L; Gammino, S; Neri, L

    2016-02-01

    Different electron guns based on cold- or hot-cathode technologies have been developed since 2009 at INFN for operating within ECR plasma chambers as sources of auxiliary electrons, with the aim of boosting the source performances by means of a higher plasma lifetime and density. Their application to microwave discharge ion sources, where plasma is not confined, has required an improvement of the gun design, in order to "screen" the cathode from the plasma particles. Experimental tests carried out on a plasma reactor show a boost of the plasma density, ranging from 10% to 90% when the electron guns are used, as explained by plasma diffusion models.

  3. High energy density physics studies at the facility for antiprotons and ion research: the HEDgeHOB collaboration

    International Nuclear Information System (INIS)

    Tahir, N.A.; Stoehlker, T.; Geissel, H.; Shutov, A.; Lomonosov, I.V.; Fortov, V.E.; Piriz, A.R.; Redmer, R.; Deutsch, C.

    2011-01-01

    The forthcoming Facility for Antiprotons and Ion Research (FAIR) at Darmstadt, is going to be a unique accelerator facility that will deliver high quality, strongly bunched, well focused, intense beams of heavy ions that will lead to unprecedented specific power deposition in solid matter. This will generate macroscopic samples of High Energy Density (HED) matter with fairly uniform physical conditions. These samples can be used to study the thermophysical and transport properties of HED matter. Extensive theoretical work has been carried out over the past decade to design numerous dedicated experiments to study HED physics at the FAIR, which has provided the basis for the HEDgeHOB (High Energy Density Matter Generated by Heavy Ion Beams) scientific proposal. This work is still in progress as the feasibility studies for more experimental schemes are being carried out. Another, very important research area that will benefit tremendously from the FAIR facility, is the production of radioactive beams. A superconducting fragment separator, Super-FRS is being designed for the production and separation of rare radioactive isotopes. Unlike the HED targets, the Super-FRS production target should not be destroyed or damaged by the beam, but should remain intact during the long experimental campaign. However, the high level of specific power deposited in the production target by the high intensity ion beam at FAIR, could cause serious problems to the target survival. These HED issues related to the Super-FRS production target are also discussed in the present paper (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Lithium and sodium ion capacitors with high energy and power densities based on carbons from recycled olive pits

    Science.gov (United States)

    Ajuria, Jon; Redondo, Edurne; Arnaiz, Maria; Mysyk, Roman; Rojo, Teófilo; Goikolea, Eider

    2017-08-01

    In this work, we are presenting both lithium and sodium ion capacitors (LIC and NIC) entirely based on electrodes designed from recycled olive pit bio-waste derived carbon materials. On the one hand, olive pits were pyrolized to obtain a low specific surface area semigraphitic hard carbon to be used as the ion intercalation (battery-type) negative electrode. On the other hand, the same hard carbon was chemically activated with KOH to obtain a high specific surface area activated carbon that was further used as the ion-adsorption (capacitor-type) positive electrode. Both electrodes were custom-made to be assembled in a hybrid cell to either build a LIC or NIC in the corresponding Li- and Na-based electrolytes. For comparison purposes, a symmetric EDLC supercapacitor cell using the same activated carbon in 1.5 M Et4NBF4/acetonitrile electrolyte was also built. Both LIC and NIC systems demonstrate remarkable energy and power density enhancement over its EDLC counterpart while showing good cycle life. This breakthrough offers the possibility to easily fabricate versatile hybrid ion capacitors, covering a wide variety of applications where different requirements are demanded.

  5. Dynamic behaviour of interphases and its implication on high-energy-density cathode materials in lithium-ion batteries

    Science.gov (United States)

    Li, Wangda; Dolocan, Andrei; Oh, Pilgun; Celio, Hugo; Park, Suhyeon; Cho, Jaephil; Manthiram, Arumugam

    2017-01-01

    Undesired electrode–electrolyte interactions prevent the use of many high-energy-density cathode materials in practical lithium-ion batteries. Efforts to address their limited service life have predominantly focused on the active electrode materials and electrolytes. Here an advanced three-dimensional chemical and imaging analysis on a model material, the nickel-rich layered lithium transition-metal oxide, reveals the dynamic behaviour of cathode interphases driven by conductive carbon additives (carbon black) in a common nonaqueous electrolyte. Region-of-interest sensitive secondary-ion mass spectrometry shows that a cathode-electrolyte interphase, initially formed on carbon black with no electrochemical bias applied, readily passivates the cathode particles through mutual exchange of surface species. By tuning the interphase thickness, we demonstrate its robustness in suppressing the deterioration of the electrode/electrolyte interface during high-voltage cell operation. Our results provide insights on the formation and evolution of cathode interphases, facilitating development of in situ surface protection on high-energy-density cathode materials in lithium-based batteries. PMID:28443608

  6. High density lower hybrid current drive and Ion Bernstein Waves heating experiments on FTU

    International Nuclear Information System (INIS)

    Pericoli-Ridolfini, V.; Panaccione, L.; Podda, S.

    1999-01-01

    An investigation of the efficiency of CD in the LH range of frequency on FTU was performed up to densities above 1x10 20 m -3 . The dependence on temperature, density, magnetic field was elucidated. Preliminary results on IBW are reported. (author)

  7. Uniform current density and divergence control in high power extraction ion diodes

    International Nuclear Information System (INIS)

    Desjarlais, M.P.; Coats, R.S.; Lockner, T.R.; Pointon, T.D.; Johnson, D.J.; Slutz, S.A.; Lemke, R.W.; Cuneo, M.E.; Mehlhorn, T.A.

    1996-01-01

    A theory of radial beam uniformity in extraction ion diodes is presented. The theory is based on a locally one-dimensional analysis of the diamagnetic compression of magnetic streamlines and the self-consistent determination of the virtual cathode location. The radial dependence of the applied magnetic field is used to determine the critical parameters of this locally one-dimensional treatment. The theory has been incorporated into the ATHETA magnetic field code to allow the rapid evaluation of realistic magnetic field configurations. Comparisons between the theoretical results, simulations with the QUICKSILVER code, and experiments on the PBFA-X accelerator establish the usefulness of this tool for tuning magnetic fields to improve ion beam uniformity. The consequences of poor beam uniformity on the evolution of ion diode instabilities are discussed with supporting evidence from simulations, theory, and experiments. (author). 8 figs., 15 refs

  8. Uniform current density and divergence control in high power extraction ion diodes

    International Nuclear Information System (INIS)

    Desjarlais, M.P.; Coats, R.S.; Lockner, T.R.; Pointon, T.D.; Johnson, D.J.; Slutz, S.A.; Lemke, R.W.; Cuneo, M.E.; Melhorn, T.A.

    1996-01-01

    A theory of radial beam uniformity in extraction ion diodes is presented. The theory is based on a locally one dimensional analysis of the diamagnetic compression of magnetic streamlines and the self consistent determination of the virtual cathode location. The radial dependence of the applied magnetic field is used to determine the critical parameters of this locally one dimensional treatment. The theory has been incorporated into the ATHETA magnetic field code to allow the rapid evaluation of realistic magnetic field configurations. Comparisons between the theoretical results, simulations with the QUICKSILVER code, and experiments on the PBFA-X accelerator establish the usefulness of this tool for tuning magnetic fields to improve ion beam uniformity. The consequences of poor beam uniformity on the evolution of ion diode instabilities are discussed with supporting evidence from simulations, theory, and experiments

  9. Uniform current density and divergence control in high power extraction ion diodes

    Energy Technology Data Exchange (ETDEWEB)

    Desjarlais, M P; Coats, R S; Lockner, T R; Pointon, T D; Johnson, D J; Slutz, S A; Lemke, R W; Cuneo, M E; Mehlhorn, T A [Sandia Labs., Albuquerque, NM (United States)

    1997-12-31

    A theory of radial beam uniformity in extraction ion diodes is presented. The theory is based on a locally one-dimensional analysis of the diamagnetic compression of magnetic streamlines and the self-consistent determination of the virtual cathode location. The radial dependence of the applied magnetic field is used to determine the critical parameters of this locally one-dimensional treatment. The theory has been incorporated into the ATHETA magnetic field code to allow the rapid evaluation of realistic magnetic field configurations. Comparisons between the theoretical results, simulations with the QUICKSILVER code, and experiments on the PBFA-X accelerator establish the usefulness of this tool for tuning magnetic fields to improve ion beam uniformity. The consequences of poor beam uniformity on the evolution of ion diode instabilities are discussed with supporting evidence from simulations, theory, and experiments. (author). 8 figs., 15 refs.

  10. Multicomponent ion transport in a mono and bilayer cation-exchange membrane at high current density

    NARCIS (Netherlands)

    Moshtari Khah, S.; Oppers, N.A.W.; de Groot, M.T.; Keurentjes, J.T.F.; Schouten, J.C.; van der Schaaf, J.

    2017-01-01

    This work describes a model for bilayer cation-exchange membranes used in the chlor-alkali process. The ion transport inside the membrane is modeled with the Nernst–Planck equation. A logistic function is used at the boundary between the two layers of the bilayer membrane to describe the change in

  11. Short bunch length detector for ion beam with high bunch density

    International Nuclear Information System (INIS)

    Tron, A.M.; Shako, V.V.

    1993-01-01

    The secondary electron rf monitors for short ion bunch phase distribution measurements are presented. Construction particularities of the monitors, influence of space charge of both the primary and the secondary electron beams on the phase resolution, thermal regime of the target during beam-target interaction are considered

  12. Coating and functionalization of high density ion track structures by atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Mättö, Laura [Department of Physics, University of Jyväskylä, P.O. Box 35 (YFL), FI-40014 (Finland); Szilágyi, Imre M., E-mail: imre.szilagyi@mail.bme.hu [Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Szent Gellért tér 4, Budapest H-1111 (Hungary); MTA-BME Technical Analytical Research Group, Szent Gellért tér 4, Budapest H-1111 (Hungary); Department of Chemistry, University of Helsinki, P.O. Box 55, Helsinki FI-00014 (Finland); Laitinen, Mikko [Department of Physics, University of Jyväskylä, P.O. Box 35 (YFL), FI-40014 (Finland); Ritala, Mikko; Leskelä, Markku [Department of Chemistry, University of Helsinki, P.O. Box 55, Helsinki FI-00014 (Finland); Sajavaara, Timo [Department of Physics, University of Jyväskylä, P.O. Box 35 (YFL), FI-40014 (Finland)

    2016-10-01

    In this study flexible TiO{sub 2} coated porous Kapton membranes are presented having electron multiplication properties. 800 nm crossing pores were fabricated into 50 μm thick Kapton membranes using ion track technology and chemical etching. Consecutively, 50 nm TiO{sub 2} films were deposited into the pores of the Kapton membranes by atomic layer deposition using Ti({sup i}OPr){sub 4} and water as precursors at 250 °C. The TiO{sub 2} films and coated membranes were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray reflectometry (XRR). Au metal electrode fabrication onto both sides of the coated foils was achieved by electron beam evaporation. The electron multipliers were obtained by joining two coated membranes separated by a conductive spacer. The results show that electron multiplication can be achieved using ALD-coated flexible ion track polymer foils. - Highlights: • Porous Kapton membranes were obtained by ion track technology and chemical etching. • TiO{sub 2} films were deposited by ALD into the pores of the Kapton membranes. • TiO{sub 2} nanotube array was prepared by removing the polymer core. • MCP structures were obtained from the coated membranes. • Electron multiplication was achieved using the ALD-coated Kapton foils.

  13. The disparate impact of the ion temperature gradient and the density gradient on edge transport and the low-high transition in tokamaks

    International Nuclear Information System (INIS)

    Kleva, Robert G.; Guzdar, Parvez N.

    2009-01-01

    Steepening of the ion temperature gradient in nonlinear fluid simulations of the edge region of a tokamak plasma causes a rapid degradation in confinement. As the density gradient steepens, there is a continuous improvement in confinement analogous to the low (L) to high (H) transition observed in tokamaks. In contrast, as the ion temperature gradient steepens, there is a rapid increase in the particle and energy fluxes and no L-H transition. For a given pressure gradient, confinement always improves when more of the pressure gradient arises from the density gradient, and less of the pressure gradient arises from the ion temperature gradient.

  14. Super high energy density of Li3V2(PO4)3 as cathode materials for lithium ion batteries

    Science.gov (United States)

    Noerochim, Lukman; Amin, Mochammad Karim Al; Susanti, Diah; Triwibowo, Joko

    2018-04-01

    Lithium ion batteries have many advantages such as high energy density, no memory effect, long time cycleability and friendly environment. One type of cathode material that can be developed is Li3V2(PO4)3. In this study has been carried out the synthesis of Li3V2(PO4)3 with a hydrothermal temperature variation of 140, 160 and 180 °C and calcination temperature at 800 °C. SEM images show that the morphology of Li3V2(PO4)3 has irregular flakes with a size between 1-10 µm. CV results show redox reaction occurs in the range between 3 V to 4.8 V with the highest specific discharge capacity of 136 mAh/g for specimen with temperature hydrothermal and calcination are 180 °C and 800 °C. This result demonstrates that Li3V2(PO4)3 has a great potential as cathode material for lithium ion battery.

  15. Composite Conducting Polymer Cathodes For High Energy Density Lithium-Ion Batteries, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future NASA planetary exploration missions require secondary (rechargeable) batteries that can operate at extreme temperatures (-60oC to 60oC) yet deliver high...

  16. Physics of intense light ion beams and production of high energy density in matter. Annual report 1994

    International Nuclear Information System (INIS)

    Bluhm, H.J.

    1995-06-01

    This report presents the results obtained in 1994 within the FZK-program on 'Physics of intense ion beams and pulsed plasmas'. It describes the present status of the 6 MW, 2 TW pulsed generator KALIF-HELIA, the production and focussing of high power ion beams and numerical simulations and experiments related to the hydrodynamics of beam matter interaction. (orig.) [de

  17. Effect of Porosity on the Thick Electrodes for High Energy Density Lithium Ion Batteries for Stationary Applications

    Directory of Open Access Journals (Sweden)

    Madhav Singh

    2016-11-01

    Full Text Available A series of 250–350 μ m-thick single-sided lithium ion cell graphite anodes and lithium nickel manganese cobalt oxide (NMC cathodes with constant area weight, but varying porosity were prepared. Over this wide thickness range, micron-sized carbon fibers were used to stabilize the electrode structure and to improve electrode kinetics. By choosing the proper porosities for the anode and cathode, kinetic limitations and aging losses during cell cycling could be minimized and energy density improved. The cell (C38%-A48% exhibits the highest energy density, 441 Wh/L at the C/10 rate, upon cycling at elevated temperature and different C-rates. The cell (C38%-A48% showed 9% higher gravimetric energy density at C/10 in comparison to the cell with as-coated electrodes.

  18. High density matter at RHIC

    Indian Academy of Sciences (India)

    QCD predicts a phase transition between hadronic matter and a quark-gluon plasma at high energy density. The relativistic heavy ion collider (RHIC) at Brookhaven National Laboratory is a new facility dedicated to the experimental study of matter under extreme conditions. Already the first round of experimental results at ...

  19. Proposal for the Study of Thermophysical Properties of High-Energy-Density Matter Using Current and Future Heavy-Ion Accelerator Facilities at GSI Darmstadt

    International Nuclear Information System (INIS)

    Tahir, N.A.; Spiller, P.; Deutsch, C.; Fortov, V.E.; Gryaznov, V.; Kulish, M.; Lomonosov, I.V.; Mintsev, V.; Nikolaev, D.; Shilkin, N.; Shutov, A.; Ternovoi, V.; Hoffmann, D.H.H.; Ni, P.; Udrea, S.; Varentsov, D.; Piriz, A.R.; Temporal, M.

    2005-01-01

    The subject of high-energy-density (HED) states in matter is of considerable importance to numerous branches of basic as well as applied physics. Intense heavy-ion beams are an excellent tool to create large samples of HED matter in the laboratory with fairly uniform physical conditions. Gesellschaft fuer Schwerionenforschung, Darmstadt, is a unique worldwide laboratory that has a heavy-ion synchrotron, SIS18, that delivers intense beams of energetic heavy ions. Construction of a much more powerful synchrotron, SIS100, at the future international facility for antiprotons and ion research (FAIR) at Darmstadt will lead to an increase in beam intensity by 3 orders of magnitude compared to what is currently available. The purpose of this Letter is to investigate with the help of two-dimensional numerical simulations, the potential of the FAIR to carry out research in the field of HED states in matter

  20. High-density carrier-accumulated and electrically stable oxide thin-film transistors from ion-gel gate dielectric.

    Science.gov (United States)

    Fujii, Mami N; Ishikawa, Yasuaki; Miwa, Kazumoto; Okada, Hiromi; Uraoka, Yukiharu; Ono, Shimpei

    2015-12-18

    The use of indium-gallium-zinc oxide (IGZO) has paved the way for high-resolution uniform displays or integrated circuits with transparent and flexible devices. However, achieving highly reliable devices that use IGZO for low-temperature processes remains a technological challenge. We propose the use of IGZO thin-film transistors (TFTs) with an ionic-liquid gate dielectric in order to achieve high-density carrier-accumulated IGZO TFTs with high reliability, and we discuss a distinctive mechanism for the degradation of this organic-inorganic hybrid device under long-term electrical stress. Our results demonstrated that an ionic liquid or gel gate dielectric provides highly reliable and low-voltage operation with IGZO TFTs. Furthermore, high-density carrier accumulation helps improve the TFT characteristics and reliability, and it is highly relevant to the electronic phase control of oxide materials and the degradation mechanism for organic-inorganic hybrid devices.

  1. Multiphoton ionization of many-electron atoms and highly-charged ions in intense laser fields: a relativistic time-dependent density functional theory approach

    Science.gov (United States)

    Tumakov, Dmitry A.; Telnov, Dmitry A.; Maltsev, Ilia A.; Plunien, Günter; Shabaev, Vladimir M.

    2017-10-01

    We develop an efficient numerical implementation of the relativistic time-dependent density functional theory (RTDDFT) to study multielectron highly-charged ions subject to intense linearly-polarized laser fields. The interaction with the electromagnetic field is described within the electric dipole approximation. The resulting time-dependent relativistic Kohn-Sham (RKS) equations possess an axial symmetry and are solved accurately and efficiently with the help of the time-dependent generalized pseudospectral method. As a case study, we calculate multiphoton ionization probabilities of the neutral argon atom and argon-like xenon ion. Relativistic effects are assessed by comparison of our present results with existing non-relativistic data.

  2. Synthesis of Three-Dimensional Nanoporous Li-Rich Layered Cathode Oxides for High Volumetric and Power Energy Density Lithium-Ion Batteries.

    Science.gov (United States)

    Qiu, Bao; Yin, Chong; Xia, Yonggao; Liu, Zhaoping

    2017-02-01

    As rechargeable Li-ion batteries have expanded their applications into on-board energy storage for electric vehicles, the energy and power must be increased to meet the new demands. Li-rich layered oxides are one of the most promising candidate materials; however, it is very difficult to make them compatible with high volumetric energy density and power density. Here, we develop an innovative approach to synthesize three-dimensional (3D) nanoporous Li-rich layered oxides Li[Li 0.144 Ni 0.136 Co 0.136 Mn 0.544 ]O 2 , directly occurring at deep chemical delithiation with carbon dioxide. It is found that the as-prepared material presents a micrometer-sized spherical structure that is typically composed of interconnected nanosized subunits with narrow distributed pores at 3.6 nm. As a result, this unique 3D micro-/nanostructure not only has a high tap density over 2.20 g cm -3 but also exhibits excellent rate capability (197.6 mA h g -1 at 1250 mA g -1 ) as an electrode. The excellent electrochemical performance is ascribed to the unique nanoporous micro-nanostructures, which facilitates the Li + diffusion and enhances the structural stability of the Li-rich layered cathode materials. Our work offers a comprehensive designing strategy to construct 3D nanoporous Li-rich layered oxides for both high volumetric energy density and power density in Li-ion batteries.

  3. High energy density of Li3-xNaxV2(PO4)3/C cathode material with high rate cycling performance for lithium-ion batteries

    Science.gov (United States)

    Zuo, Zong-Lin; Deng, Jian-Qiu; Pan, Jin; Luo, Wen-Bin; Yao, Qing-Rong; Wang, Zhong-Min; Zhou, Huai-Ying; Liu, Hua-Kun

    2017-07-01

    A serials of micro-sized Li3-xNaxV2(PO4)3/C composite has been synthesized by sol-gel method, comprised of numerous primary nanocrystals. This structure can efficiently facilitate lithium-ion transport in secondary aggregated individual particles due to the short diffusion distance among primary nanocrystals, along with a high tap density. With the increasing of Na doping content, the structure evolution occurs in Li3-xNaxV2(PO4)3 from a single-phase structure to a two-phase structure. The appearance of rhombohedral phase can provide a larger free volume of the interstitial space, fastening ionic movement to offer an excellent high rate capability. Furthermore, Na doping can stabilize the rhombohedral structure of the V2(PO4)3 framework, leading to the remarkable cycling stability. Among all the composites, Li2.6Na0.4V2(PO4)3/C presents the best electrochemical performance with a high energy density of 478.8 Wh kg-1, delivering high initial discharge capacities of 121.6, 113.8 and 109.7 mAh g-1 at the rate of 5 C, 10 C and 20 C in a voltage range of 3.0 - 4.3 V, respectively. It also exhibit an excellent high rate cycling performance, with capacity retention of 85.9 %, 81.7 % and 76.5 % after 1000 cycles at the rate of 5 C, 10 C and 20 C in a voltage range of 3.0 - 4.3 V.

  4. High density operation in pulsator

    International Nuclear Information System (INIS)

    Klueber, O.; Cannici, B.; Engelhardt, W.; Gernhardt, J.; Glock, E.; Karger, F.; Lisitano, G.; Mayer, H.M.; Meisel, D.; Morandi, P.

    1976-03-01

    This report summarizes the results of experiments at high electron densities (>10 14 cm -3 ) which have been achieved by pulsed gas inflow during the discharge. At these densities a regime is established which is characterized by βsub(p) > 1, nsub(i) approximately nsub(e), Tsub(i) approximately Tsub(e) and tausub(E) proportional to nsub(e). Thus the toroidal magnetic field contributes considerably to the plasma confinement and the ions constitute almost half of the plasma pressure. Furthermore, the confinement is appreciably improved and the plasma becomes impermeable to hot neutrals. (orig.) [de

  5. Studies of thermophysical properties of high-energy-density states in matter using intense heavy ion beams at the future Fair accelerator facilities: The HEDgeHOB collaboration

    International Nuclear Information System (INIS)

    Tahir, N.A.; Deutsch, C.; Hoffmann, D.H.H.; Shutov, A.; Lomonosov, I.V.; Gryaznov, V.; Fortov, V.E.; Hoffmann, D.H.H.; Ni, P.; Udrea, S.; Varentsov, D.; Piriz, A.R.; Wouchuk, G.

    2006-01-01

    Intense beams of energetic heavy ions are believed to be a very efficient and novel tool to create states of High-Energy-Density (HED) in matter. This paper shows with the help of numerical simulations that the heavy ion beams that will be generated at the future Facility for Antiprotons and Ion Research (FAIR) will allow one to use two different experimental schemes to study HED states in matter. The German government has recently approved the construction of FAIR at Darmstadt. First scheme named HIHEX (Heavy Ion Heating and EXpansion), will generate high-pressure, high-entropy states in matter by volumetric isochoric heating. The heated material will then be allowed to expand in an isentropic way. Using this scheme, it will be possible to study important regions of the phase diagram that are either difficult to access or are even unaccessible using traditional methods of shock compression. The second scheme would allow one to achieve low-entropy compression of a sample material like hydrogen or water to produce conditions that are believed to exist in the interiors of the giant planets. This scheme is named LAPLAS after Laboratory Planetary Sciences. (authors)

  6. Synthesis and characterization of high-density LiFePO4/C composites as cathode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Chang Zhaorong; Lv Haojie; Tang Hongwei; Li Huaji; Yuan Xiaozi; Wang Haijiang

    2009-01-01

    To achieve a high-energy-density lithium electrode, high-density LiFePO 4 /C composite cathode material for a lithium-ion battery was synthesized using self-produced high-density FePO 4 as a precursor, glucose as a C source, and Li 2 CO 3 as a Li source, in a pipe furnace under an atmosphere of 5% H 2 -95% N 2 . The structure of the synthesized material was analyzed and characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The electrochemical properties of the synthesized LiFePO 4 /carbon composite were investigated by cyclic voltammetry (CV) and the charge/discharge process. The tap-density of the synthesized LiFePO 4 /carbon composite powder with a carbon content of 7% reached 1.80 g m -3 . The charge/discharge tests show that the cathode material has initial charge/discharge capacities of 190.5 and 167.0 mAh g -1 , respectively, with a volume capacity of 300.6 mAh cm -3 , at a 0.1C rate. At a rate of 5C, the LiFePO 4 /carbon composite shows a high discharge capacity of 98.3 mAh g -1 and a volume capacity of 176.94 mAh cm -3 .

  7. Balance of ionization and recombination of carbon ions in high density peripheral plasmas of the JT-60 U tokamak

    International Nuclear Information System (INIS)

    Nakano, T.; Kubo, H.; Asakura, N.; Shimizu, K.

    2009-01-01

    In high density and low temperature peripheral plasmas of JT-60 U, i.e. detached divertor plasmas, C III and C IV lines were observed by a visible and VUV spectrometers in order to investigate dominant radiators, radiation power and particle balance between the radiators. An emission peak was found between the inner strike and the X-point. With increasing electron density, the emission peak moved to the X-point with a constant electron temperature of ∼7 eV. In the case the emission peak was located on the X-point, the dominant radiators in the emission peak were C 2+ and C 3+ , which contributed 30% and 60% to the total radiative power. It was found that C 3+ was produced by the ionization of C 2+ and the volume recombination of C 4+ at a similar rates. However, the loss flux of C 3+ was lower by two orders of magnitude than the C 3+ production flux, indicating that another loss mechanism such as transport loss around the X-point was significant.

  8. High density dispersion fuel

    International Nuclear Information System (INIS)

    Hofman, G.L.

    1996-01-01

    A fuel development campaign that results in an aluminum plate-type fuel of unlimited LEU burnup capability with an uranium loading of 9 grams per cm 3 of meat should be considered an unqualified success. The current worldwide approved and accepted highest loading is 4.8 g cm -3 with U 3 Si 2 as fuel. High-density uranium compounds offer no real density advantage over U 3 Si 2 and have less desirable fabrication and performance characteristics as well. Of the higher-density compounds, U 3 Si has approximately a 30% higher uranium density but the density of the U 6 X compounds would yield the factor 1.5 needed to achieve 9 g cm -3 uranium loading. Unfortunately, irradiation tests proved these peritectic compounds have poor swelling behavior. It is for this reason that the authors are turning to uranium alloys. The reason pure uranium was not seriously considered as a dispersion fuel is mainly due to its high rate of growth and swelling at low temperatures. This problem was solved at least for relatively low burnup application in non-dispersion fuel elements with small additions of Si, Fe, and Al. This so called adjusted uranium has nearly the same density as pure α-uranium and it seems prudent to reconsider this alloy as a dispersant. Further modifications of uranium metal to achieve higher burnup swelling stability involve stabilization of the cubic γ phase at low temperatures where normally α phase exists. Several low neutron capture cross section elements such as Zr, Nb, Ti and Mo accomplish this in various degrees. The challenge is to produce a suitable form of fuel powder and develop a plate fabrication procedure, as well as obtain high burnup capability through irradiation testing

  9. High-Energy-Density Aqueous Magnesium-Ion Battery Based on a Carbon-Coated FeVO4 Anode and a Mg-OMS-1 Cathode.

    Science.gov (United States)

    Zhang, Hongyu; Ye, Ke; Zhu, Kai; Cang, Ruibai; Yan, Jun; Cheng, Kui; Wang, Guiling; Cao, Dianxue

    2017-12-01

    Porous FeVO 4 is prepared by hydrothermal method and further modified by coating with carbon to obtain FeVO 4 /C with a hierarchical pore structure. FeVO 4 /C is used as an anodic electrode in aqueous rechargeable magnesium-ion batteries. The FeVO 4 /C material not only has improved electrical conductivity as a result of the carbon coating layer, but also has an increased specific surface area as a result of the hierarchical pore structure, which is beneficial for magnesium-ion insertion/deinsertion. Therefore, an aqueous rechargeable magnesium-ion full battery is successfully constructed with FeVO 4 /C as the anode, Mg-OMS-1 (OMS=octahedral molecular sieves) as the cathode, and 1.0 mol L -1 MgSO 4 as the electrolyte. The discharge capacity of the Mg-OMS-1//FeVO 4 /C aqueous battery is 58.9 mAh g -1 at a current density of 100 mA g -1 ; this value is obtained by calculating the total mass of two electrodes and the capacity retention rate of this device is 97.7 % after 100 cycles, with almost 100 % coulombic efficiency, which indicates that the system has a good electrochemical reversibility. Additionally, this system can achieve a high energy density of 70.4 Wh kg -1 , which provides powerful evidence that an aqueous magnesium-ion battery is possible. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. In situ electrochemical creation of cobalt oxide nanosheets with favorable performance as a high tap density anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Lin, Qian; Sha, Yujing; Zhao, Bote; Chen, Yubo; Tadé, Moses O.; Shao, Zongping

    2015-01-01

    Highlights: • Cobalt oxide nanosheets in situ electrochemical generated from commercial LiCoO_2. • TEM indicates creation of cobalt oxide nanosheets from coarse layered LiCoO_2_. • Coarse-type LiCoO_2 with high tap density shows promising anode performance. • Optimizing weight ratio of LiCoO_2 in electrode, a high capacity was achieved. - Abstract: Cobalt oxides are attractive alternative anode materials for next-generation lithium-ion batteries (LIBs). To improve the performance of conversion-type anode materials such as cobalt oxides, well dispersed and nanosized particulate morphology is typically required. In this study, we describe the in situ electrochemical generation of cobalt oxide nanosheets from commercial micrometer-sized LiCoO_2 oxide as an anode material for LIBs. The electrode material as prepared was analyzed by XRD, FE-SEM and TEM. The electrochemical properties were investigated by cyclic voltammetry and by a constant current galvanostatic discharge–charge test. The material shows a high tap density and promising anode performance in terms of capacity, rate performance and cycling stability. A capacity of 560 mA h g"−"1 is still achieved at a current density of 1000 mA g"−"1 by increasing the amount of additives in the electrode to 40 wt%. This paper provides a new technique for developing a high-performance conversion-type anode for LIBs.

  11. Constraints on the high-density nuclear equation of state from the phenomenology of compact stars and heavy-ion collisions

    International Nuclear Information System (INIS)

    Klaehn, T.; Blaschke, D.; Typel, S.; Dalen, E. N. E. van; Faessler, A.; Fuchs, C.; Gaitanos, T.; Wolter, H. H.; Grigorian, H.; Ho, A.; Weber, F.; Kolomeitsev, E. E.; Miller, M. C.; Roepke, G.; Truemper, J.; Voskresensky, D. N.

    2006-01-01

    A new scheme for testing nuclear matter equations of state (EoSs) at high densities using constraints from neutron star (NS) phenomenology and a flow data analysis of heavy-ion collisions is suggested. An acceptable EoS shall not allow the direct Urca process to occur in NSs with masses below 1.5M · , and also shall not contradict flow and kaon production data of heavy-ion collisions. Compact star constraints include the mass measurements of 2.1±0.2M · (1σ level) for PSR J0751+1807 and of 2.0±0.1M · from the innermost stable circular orbit for 4U 1636-536, the baryon mass--gravitational mass relationships from Pulsar B in J0737-3039 and the mass-radius relationships from quasiperiodic brightness oscillations in 4U 0614+09 and from the thermal emission of RX J1856-3754. This scheme is applied to a set of relativistic EoSs which are constrained otherwise from nuclear matter saturation properties. We demonstrate on the given examples that the test scheme due to the quality of the newly emerging astrophysical data leads to useful selection criteria for the high-density behavior of nuclear EoSs

  12. High current ion sources

    International Nuclear Information System (INIS)

    Brown, I.G.

    1989-06-01

    The concept of high current ion source is both relative and evolutionary. Within the domain of one particular kind of ion source technology a current of microamperers might be 'high', while in another area a current of 10 Amperes could 'low'. Even within the domain of a single ion source type, what is considered high current performance today is routinely eclipsed by better performance and higher current output within a short period of time. Within their fields of application, there is a large number of kinds of ion sources that can justifiably be called high current. Thus, as a very limited example only, PIGs, Freemen sources, ECR sources, duoplasmatrons, field emission sources, and a great many more all have their high current variants. High current ion beams of gaseous and metallic species can be generated in a number of different ways. Ion sources of the kind developed at various laboratories around the world for the production of intense neutral beams for controlled fusion experiments are used to form large area proton deuteron beams of may tens of Amperes, and this technology can be used for other applications also. There has been significant progress in recent years in the use of microwave ion sources for high current ion beam generation, and this method is likely to find wide application in various different field application. Finally, high current beams of metal ions can be produced using metal vapor vacuum arc ion source technology. After a brief consideration of high current ion source design concepts, these three particular methods are reviewed in this paper

  13. Development of high-polarization Fe/Ge neutron polarizing supermirror: Possibility of fine-tuning of scattering length density in ion beam sputtering

    Science.gov (United States)

    Maruyama, R.; Yamazaki, D.; Akutsu, K.; Hanashima, T.; Miyata, N.; Aoki, H.; Takeda, M.; Soyama, K.

    2018-04-01

    The multilayer structure of Fe/Si and Fe/Ge systems fabricated by ion beam sputtering (IBS) was investigated using X-ray and polarized neutron reflectivity measurements and scanning transmission electron microscopy with energy-dispersive X-ray analysis. The obtained result revealed that the incorporation of sputtering gas particles (Ar) in the Ge layer gives rise to a marked reduction in the neutron scattering length density (SLD) and contributes to the SLD contrast between the Fe and Ge layers almost vanishing for spin-down neutrons. Bundesmann et al. (2015) have shown that the implantation of primary Ar ions backscattered at the target is responsible for the incorporation of Ar particles and that the fraction increases with increasing ion incidence angle and increasing polar emission angle. This leads to a possibility of fine-tuning of the SLD for the IBS, which is required to realize a high polarization efficiency of a neutron polarizing supermirror. Fe/Ge polarizing supermirror with m = 5 fabricated under the same condition showed a spin-up reflectivity of 0.70 at the critical momentum transfer. The polarization was higher than 0.985 for the qz range where the correction for the polarization inefficiencies of the beamline works properly. The result of the polarized neutron reflectivity measurement suggests that the "magnetically-dead" layers formed at both sides of the Fe layer, together with the SLD contrast, play a critical role in determining the polarization performance of a polarizing supermirror.

  14. Synthesis and characterization of high-density LiFePO{sub 4}/C composites as cathode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Chang Zhaorong [College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007 (China)], E-mail: czr_56@163.com; Lv Haojie; Tang Hongwei; Li Huaji [College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007 (China); Yuan Xiaozi; Wang Haijiang [Institute for Fuel Cell Innovation, National Research Council of Canada, Vancouver, BC, V6T 1W5 (Canada)

    2009-08-01

    To achieve a high-energy-density lithium electrode, high-density LiFePO{sub 4}/C composite cathode material for a lithium-ion battery was synthesized using self-produced high-density FePO{sub 4} as a precursor, glucose as a C source, and Li{sub 2}CO{sub 3} as a Li source, in a pipe furnace under an atmosphere of 5% H{sub 2}-95% N{sub 2}. The structure of the synthesized material was analyzed and characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The electrochemical properties of the synthesized LiFePO{sub 4}/carbon composite were investigated by cyclic voltammetry (CV) and the charge/discharge process. The tap-density of the synthesized LiFePO{sub 4}/carbon composite powder with a carbon content of 7% reached 1.80 g m{sup -3}. The charge/discharge tests show that the cathode material has initial charge/discharge capacities of 190.5 and 167.0 mAh g{sup -1}, respectively, with a volume capacity of 300.6 mAh cm{sup -3}, at a 0.1C rate. At a rate of 5C, the LiFePO{sub 4}/carbon composite shows a high discharge capacity of 98.3 mAh g{sup -1} and a volume capacity of 176.94 mAh cm{sup -3}.

  15. High brightness ion source

    International Nuclear Information System (INIS)

    Dreyfus, R.W.; Hodgson, R.T.

    1975-01-01

    A high brightness ion beam is obtainable by using lasers to excite atoms or molecules from the ground state to an ionized state in increments, rather than in one step. The spectroscopic resonances of the atom or molecule are used so that relatively long wavelength, low power lasers can be used to obtain such ion beam

  16. Optimum extracted H- and D- current densities from gas-pressure-limited high-power hydrogen/deuterium tandem ion sources

    International Nuclear Information System (INIS)

    Hiskes, J.R.

    1993-01-01

    The tandem hydrogen/deuterium ion source is modelled for the purpose of identifying the maximum current densities that can be extracted subject to the gas-pressure constraints proposed for contemporary beam-line systems. Optimum useful extracted current densities are found to be in the range of approximately 7 to 10 mA cm -2 . The sensitivity of these current densities is examined subject to uncertainties in the underlying atomic/molecular rate processes; A principal uncertainty remains the quantification of the molecular vibrational distribution following H 3 + wall collisions

  17. 2.5-dimensional numerical modeling of the formation of a plasma channel due to ion redistribution during the propagation of a finite sequence of relativistic electron bunches through high-density and low-density plasmas

    International Nuclear Information System (INIS)

    Karas, V.I.; Karas, I.V.; Levchenko, V.D.; Sigov, Yu.S.; Fainberg, Ya.B.

    1997-01-01

    Results of numerical simulations of the excitation of wake fields in high- and low-density plasmas are presented. The propagation of relativistic electron bunches in a plasma is described by a closed set of relativistic Vlasov equations for two spatial coordinates and three velocity coordinates for each plasma component and the nonlinear Maxwell equations for self-consistent electromagnetic fields. Numerical modeling shows that, under ordinary experimental conditions (when the length and radius of the bunch are much less than the skin depth), the radius of the bunches propagating in a plasma varies over a wide range. In this case, the dynamics of both the plasma and the bunches is nonlinear. The radial redistribution of the plasma ions in self-consistent fields leads to the formation of a plasma channel. Incorporating this phenomenon is important for studying the propagation of relativistic electron bunches in a plasma

  18. High density hydrogen research

    International Nuclear Information System (INIS)

    Hawke, R.S.

    1977-01-01

    The interest in the properties of very dense hydrogen is prompted by its abundance in Saturn and Jupiter and its importance in laser fusion studies. Furthermore, it has been proposed that the metallic form of hydrogen may be a superconductor at relatively high temperatures and/or exist in a metastable phase at ambient pressure. For ten years or more, laboratories have been developing the techniques to study hydrogen in the megabar region (1 megabar = 100 GPa). Three major approaches to study dense hydrogen experimentally have been used, static presses, shockwave compression, and magnetic compression. Static tchniques have crossed the megabar threshold in stiff materials but have not yet been convincingly successful in very compressible hydrogen. Single and double shockwave techniques have improved the precision of the pressure, volume, temperature Equation of State (EOS) of molecular hydrogen (deuterium) up to near 1 Mbar. Multiple shockwave and magnetic techniques have compressed hydrogen to several megabars and densities in the range of the metallic phase. The net result is that hydrogen becomes conducting at a pressure between 2 and 4 megabars. Hence, the possibility of making a significant amount of hydrogen into a metal in a static press remains a formidable challenge. The success of such experiments will hopefully answer the questions about hydrogen's metallic vs. conducting molecular phase, superconductivity, and metastability. 4 figures, 15 references

  19. High Power Density Motors

    Science.gov (United States)

    Kascak, Daniel J.

    2004-01-01

    With the growing concerns of global warming, the need for pollution-free vehicles is ever increasing. Pollution-free flight is one of NASA's goals for the 21" Century. , One method of approaching that goal is hydrogen-fueled aircraft that use fuel cells or turbo- generators to develop electric power that can drive electric motors that turn the aircraft's propulsive fans or propellers. Hydrogen fuel would likely be carried as a liquid, stored in tanks at its boiling point of 20.5 K (-422.5 F). Conventional electric motors, however, are far too heavy (for a given horsepower) to use on aircraft. Fortunately the liquid hydrogen fuel can provide essentially free refrigeration that can be used to cool the windings of motors before the hydrogen is used for fuel. Either High Temperature Superconductors (HTS) or high purity metals such as copper or aluminum may be used in the motor windings. Superconductors have essentially zero electrical resistance to steady current. The electrical resistance of high purity aluminum or copper near liquid hydrogen temperature can be l/lOO* or less of the room temperature resistance. These conductors could provide higher motor efficiency than normal room-temperature motors achieve. But much more importantly, these conductors can carry ten to a hundred times more current than copper conductors do in normal motors operating at room temperature. This is a consequence of the low electrical resistance and of good heat transfer coefficients in boiling LH2. Thus the conductors can produce higher magnetic field strengths and consequently higher motor torque and power. Designs, analysis and actual cryogenic motor tests show that such cryogenic motors could produce three or more times as much power per unit weight as turbine engines can, whereas conventional motors produce only 1/5 as much power per weight as turbine engines. This summer work has been done with Litz wire to maximize the current density. The current is limited by the amount of heat it

  20. Supernovae and high density nuclear matter

    International Nuclear Information System (INIS)

    Kahana, S.

    1986-01-01

    The role of the nuclear equation of state (EOS) in producing prompt supernova explosions is examined. Results of calculations of Baron, Cooperstein, and Kahana incorporating general relativity and a new high density EOS are presented, and the relevance of these calculations to laboratory experiments with heavy ions considered. 31 refs., 6 figs., 2 tabs

  1. Supernovae and high density nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Kahana, S.

    1986-01-01

    The role of the nuclear equation of state (EOS) in producing prompt supernova explosions is examined. Results of calculations of Baron, Cooperstein, and Kahana incorporating general relativity and a new high density EOS are presented, and the relevance of these calculations to laboratory experiments with heavy ions considered. 31 refs., 6 figs., 2 tabs.

  2. Effects of retarded electrical fields on observables sensitive to the high-density behavior of the nuclear symmetry energy in heavy-ion collisions at intermediate energies

    Science.gov (United States)

    Wei, Gao-Feng; Li, Bao-An; Yong, Gao-Chan; Ou, Li; Cao, Xin-Wei; Liu, Xu-Yang

    2018-03-01

    Within the isospin- and momentum-dependent transport model IBUU11, we examine the relativistic retardation effects of electrical fields on the π-/π+ ratio and neutron-proton differential transverse flow in heavy-ion collisions at intermediate energies. Compared to the static Coulomb fields, the retarded electric fields of fast-moving charges are known to be anisotropic and the associated relativistic corrections can be significant. They are found to increase the number of energetic protons in the participant region at the maximum compression by as much as 25% but that of energetic neutrons by less than 10% in 197Au+197Au reactions at a beam energy of 400 MeV/nucleon. Consequently, more π+ and relatively fewer π- mesons are produced, leading to an appreciable reduction of the π-/π+ ratio compared to calculations with the static Coulomb fields. Also, the neutron-proton differential transverse flow, as another sensitive probe of high-density symmetry energy, is also decreased appreciably due to the stronger retarded electrical fields in directions perpendicular to the velocities of fast-moving charges compared to calculations using the isotropic static electrical fields. Moreover, the retardation effects on these observables are found to be approximately independent of the reaction impact parameter.

  3. Simple, high current, antimony ion source

    International Nuclear Information System (INIS)

    Sugiura, H.

    1979-01-01

    A simple metal ion source capable of producing a continuous, uncontaminated, high current beam of Sb ions is presented. It produced a total ion current of 200 μA at 1 kV extraction voltage. A discharge occurred in the source at a pressure of 6 x 10 -4 Torr. The ion current extracted from the source increased with the 3/2 power of the extraction voltage. The perveance of the source and ion density in the plasma were 8 x 10 -9 and 1.8 x 10 11 cm -3 , respectively

  4. Process controls for improving bioleaching performance of both Li and Co from spent lithium ion batteries at high pulp density and its thermodynamics and kinetics exploration.

    Science.gov (United States)

    Niu, Zhirui; Zou, Yikan; Xin, Baoping; Chen, Shi; Liu, Changhao; Li, Yuping

    2014-08-01

    Release of Co and Li from spent lithium ion batteries (LIBs) by bioleaching has attracted growing attentions. However, the pulp density was only 1% or lower, meaning that a huge quantity of media was required for bioleaching. In this work, bioleaching behavior of the spent LIBs at pulp densities ranging from 1% to 4% was investigated and process controls to improve bioleaching performance at pulp density of 2% were explored. The results showed that the pulp density exerted a considerable influence on leaching performance of Co and Li. The bioleaching efficiency decreased respectively from 52% to 10% for Co and from 80% to 37% for Li when pulp density rose from 1% to 4%. However, the maximum extraction efficiency of 89% for Li and 72% for Co was obtained at pulp density of 2% by process controls. Bioleaching of the spent LIBs has much greater potential to occur than traditional chemical leaching based on thermodynamics analysis. The product layer diffusion model described best bioleaching behavior of Co and Li. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Performance Degradation of Thermal Parameters during Cycle Ageing of High Energy Density Ni-Mn-Co based Lithium-Ion Battery Cells

    DEFF Research Database (Denmark)

    Stanciu, Tiberiu; Stroe, Daniel Loan; Swierczynski, Maciej Jozef

    2016-01-01

    The accelerated demand for electrifying the transportation sector, coupled with the continuous improvement of rechargeable batteries’ characteristics, have made modern high-energy Lithium-ion (Li-ion) batteries the standard choice for hybrid and electric vehicles (EVs). Consequently, Li......-ion batteries’ electrochemical and thermal characteristics are very important topics, putting them at the forefront of the research. Along with the electrical performance of Li-ion battery cells, their thermal behavior needs to be accurately predicted during operation and over the lifespan of the application...... as well, since the thermal management of the battery is crucial for the safety of the EV driver. Moreover, the thermal management system can significantly lower the degradation rate of the battery pack and thus reduce costs. In this paper, the thermal characterization of a commercially available Nickel...

  6. Energy density, stopping and flow in ultrarelativistic heavy ion collisions

    International Nuclear Information System (INIS)

    Sorge, H.; von Keitz, A.; Mattiello, R.; Stoecker, H.; Greiner, W.

    1990-01-01

    The Lorentz invariant molecular dynamics approach (RQMD) is employed to investigate the space-time evolution of heavy ion collisions at energies (E kin = 10AGeV hor-ellipsis 200AGeV). The calculations for various nucleus nucleus reactions show a high degree of stopping power. The importance of secondary rescattering at these beam energies is demonstrated. The computed nucleon rapidity distributions are compared to available experimental data. It is demonstrated that nonlinear, collective effects like full stopping of target and projectile and matter flow could be expected for heavy projectiles only. For nuclear collisions in the Booster era at BNL and for the lead beam at CERN SPS the authors predict a stimulating future: then a nearly equilibrated, long lived (8 fm/c) macroscopic volume of very high energy density (> 1 GeV/fm 3 ) and baryon density (> 5 times ground state density) is produced

  7. Nitrogen-Doped Holey Graphene as an Anode for Lithium-Ion Batteries with High Volumetric Energy Density and Long Cycle Life.

    Science.gov (United States)

    Xu, Jiantie; Lin, Yi; Connell, John W; Dai, Liming

    2015-12-01

    Nitrogen-doped holey graphene (N-hG) as an anode material for lithium-ion batteries has delivered a maximum volumetric capacity of 384 mAh cm(-3) with an excellent long-term cycling life up to 6000 cycles, and as an electrochemical capacitor has delivered a maximum volumetric energy density of 171.2 Wh L(-1) and a volumetric capacitance of 201.6 F cm(-3) . © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Improved GAMMA 10 tandem mirror confinement in high density plasma

    International Nuclear Information System (INIS)

    Yatsu, K.; Cho, T.; Higaki, H.; Hirata, M.; Hojo, H.; Ichimura, M.; Ishii, K.; Ishimoto, Y.; Itakura, A.; Katanuma, I.; Kohagura, J.; Minami, R.; Nakashima, Y.; Numakura, T.; Saito, T.; Saosaki, S.; Takemura, Y.; Tatematsu, Y.; Yoshida, M.; Yoshikawa, M.

    2003-01-01

    GAMMA 10 experiments have advanced in high density experiments after the last IAEA fusion energy conference in 2000 where we reported the production of the high density plasma through use of ion cyclotron range of frequency heating at a high harmonic frequency and neutral beam injection in the anchor cells. However, the diamagnetic signal of the plasma decreased when electron cyclotron resonance heating was applied for the potential formation. Recently a high density plasma has been obtained without degradation of the diamagnetic signal and with much improved reproducibility than before. The high density plasma was attained through adjustment of the spacing of the conducting plates installed in the anchor transition regions. The potential confinement of the plasma has been extensively studied. Dependences of the ion confinement time, ion-energy confinement time and plasma confining potential on plasma density were obtained for the first time in the high density region up to a density of 4x10 18 m -3 . (author)

  9. High Intensity High Charge State ECR Ion Sources

    CERN Document Server

    Leitner, Daniela

    2005-01-01

    The next-generation heavy ion beam accelerators such as the proposed Rare Isotope Accelerator (RIA), the Radioactive Ion Beam Factory at RIKEN, the GSI upgrade project, the LHC-upgrade, and IMP in Lanzhou require a great variety of high charge state ion beams with a magnitude higher beam intensity than currently achievable. High performance Electron Cyclotron Resonance (ECR) ion sources can provide the flexibility since they can routinely produce beams from hydrogen to uranium. Over the last three decades, ECR ion sources have continued improving the available ion beam intensities by increasing the magnetic fields and ECR heating frequencies to enhance the confinement and the plasma density. With advances in superconducting magnet technology, a new generation of high field superconducting sources is now emerging, designed to meet the requirements of these next generation accelerator projects. The talk will briefly review the field of high performance ECR ion sources and the latest developments for high intens...

  10. High energy ion implantation

    International Nuclear Information System (INIS)

    Ziegler, J.F.

    1985-01-01

    High energy ion implantation offers the oppertunity for unique structures in semiconductor processing. The unusual physical properties of such implantations are discussed as well as the special problems in masking and damage annealing. A review is made of proposed circuit structures which involve deep implantation. Examples are: deep buried bipolar collectors fabricated without epitaxy, barrier layers to reduce FET memory sensitivity to soft-fails, CMOS isolation well structures, MeV implantation for customization and correction of completed circuits, and graded reach-throughs to deep active device components. (orig.)

  11. Metallic ions catalysis for improving bioleaching yield of Zn and Mn from spent Zn-Mn batteries at high pulp density of 10.

    Science.gov (United States)

    Niu, Zhirui; Huang, Qifei; Wang, Jia; Yang, Yiran; Xin, Baoping; Chen, Shi

    2015-11-15

    Bioleaching of spent batteries was often conducted at pulp density of 1.0% or lower. In this work, metallic ions catalytic bioleaching was used for release Zn and Mn from spent ZMBs at 10% of pulp density. The results showed only Cu(2+) improved mobilization of Zn and Mn from the spent batteries among tested four metallic ions. When Cu(2+) content increased from 0 to 0.8 g/L, the maximum release efficiency elevated from 47.7% to 62.5% for Zn and from 30.9% to 62.4% for Mn, respectively. The Cu(2+) catalysis boosted bioleaching of resistant hetaerolite through forming a possible intermediate CuMn2O4 which was subject to be attacked by Fe(3+) based on a cycle of Fe(3+)/Fe(2+). However, poor growth of cells, formation of KFe3(SO4)2(OH)6 and its possible blockage between cells and energy matters destroyed the cycle of Fe(3+)/Fe(2+), stopping bioleaching of hetaerolite. The chemical reaction controlled model fitted best for describing Cu(2+) catalytic bioleaching of spent ZMBs. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Effects of low central fuelling on density and ion temperature profiles in reversed shear plasmas on JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Takenaga, H; Ide, S; Sakamoto, Y; Fujita, T [Japan Atomic Energy Agency, Naka Ibaraki 311-0193 (Japan)], E-mail: takenaga.hidenobu@jaea.go.jp

    2008-07-15

    Effects of low central fuelling on density and ion temperature profiles have been investigated using negative ion based neutral beam injection and electron cyclotron heating (ECH) in reversed shear plasmas on JT-60U. Strong internal transport barrier (ITB) was maintained in density and ion temperature profiles, when central fuelling was decreased by switching positive ion based neutral beam injection to ECH after the strong ITB formation. Similar density and ion temperature ITBs were formed for the low and high central fuelling cases during the plasma current ramp-up phase. Strong correlation between the density gradient and the ion temperature gradient was observed, indicating that particle transport and ion thermal transport are strongly coupled or the density gradient assists the ion temperature ITB formation through suppression of drift wave instabilities such as ion temperature gradient mode. These results support that the density and ion temperature ITBs can be formed under reactor relevant conditions.

  13. Effects of low central fuelling on density and ion temperature profiles in reversed shear plasmas on JT-60U

    Science.gov (United States)

    Takenaga, H.; Ide, S.; Sakamoto, Y.; Fujita, T.; JT-60 Team

    2008-07-01

    Effects of low central fuelling on density and ion temperature profiles have been investigated using negative ion based neutral beam injection and electron cyclotron heating (ECH) in reversed shear plasmas on JT-60U. Strong internal transport barrier (ITB) was maintained in density and ion temperature profiles, when central fuelling was decreased by switching positive ion based neutral beam injection to ECH after the strong ITB formation. Similar density and ion temperature ITBs were formed for the low and high central fuelling cases during the plasma current ramp-up phase. Strong correlation between the density gradient and the ion temperature gradient was observed, indicating that particle transport and ion thermal transport are strongly coupled or the density gradient assists the ion temperature ITB formation through suppression of drift wave instabilities such as ion temperature gradient mode. These results support that the density and ion temperature ITBs can be formed under reactor relevant conditions.

  14. High resolution studies of the origins of polyatomic ions in inductively coupled plasma-mass spectrometry, Part I. Identification methods and effects of neutral gas density assumptions, extraction voltage, and cone material

    International Nuclear Information System (INIS)

    Ferguson, Jill Wisnewski; Houk, R.S.

    2006-01-01

    Common polyatomic ions (ArO + , NO + , H 2 O + , H 3 O + , Ar 2 + , ArN + , OH + , ArH + , O 2 + ) in inductively coupled plasma-mass spectrometry (ICP-MS) are identified using high mass resolution and studied using kinetic gas temperatures (T gas ) determined from a dissociation reaction approach. Methods for making accurate mass measurements, confirming ion identifications, and correcting for mass bias are discussed. The effects of sampler and skimmer cone composition and extraction voltage on polyatomic ion formation are also explored. Neutral species densities at several locations in the extraction interface are estimated and the corresponding effects of the T gas value are calculated. The results provide information about the origins of background ions and indicate possible locations for their formation or removal

  15. Production of High-Intensity, Highly Charged Ions

    CERN Document Server

    Gammino, S.

    2013-12-16

    In the past three decades, the development of nuclear physics facilities for fundamental and applied science purposes has required an increasing current of multicharged ion beams. Multiple ionization implies the formation of dense and energetic plasmas, which, in turn, requires specific plasma trapping configurations. Two types of ion source have been able to produce very high charge states in a reliable and reproducible way: electron beam ion sources (EBIS) and electron cyclotron resonance ion sources (ECRIS). Multiple ionization is also obtained in laser-generated plasmas (laser ion sources (LIS)), where the high-energy electrons and the extremely high electron density allow step-by-step ionization, but the reproducibility is poor. This chapter discusses the atomic physics background at the basis of the production of highly charged ions and describes the scientific and technological features of the most advanced ion sources. Particular attention is paid to ECRIS and the latest developments, since they now r...

  16. High-ion temperature experiments with negative-ion-based NBI in LHD

    International Nuclear Information System (INIS)

    Takeiri, Y.; Morita, S.; Tsumori, K.; Ikeda, K.; Oka, Y.; Osakabe, M.; Nagaoka, K.; Goto, M.; Miyazawa, J.; Masuzaki, S.; Ashikawa, N.; Yokoyama, M.; Narihara, K.; Yamada, I.; Kubo, S.; Shimozuma, T.; Inagaki, S.; Tanaka, K.; Peterson, B.J.; Ida, K.; Kaneko, O.; Komori, A.; Murakami, S.

    2005-01-01

    High-Z plasmas have been produced with Ar- and/or Ne-gas fuelling to increase the ion temperature in the LHD plasmas heated with the high-energy negative-ion-based NBI. Although the electron heating is dominant in the high-energy NBI heating, the direct ion heating power is much enhanced effectively in low-density plasmas due to both an increase in the beam absorption (ionisation) power and a reduction of the ion density in the high-Z plasmas. Intensive Ne- and/or Ar-glow discharge cleaning works well to suppress dilution of the high-Z plasmas with the wall-absorbed hydrogen. As a result, the ion temperature increases with an increase in the ion heating power normalized by the ion density, and reaches 10 keV. An increase in the ion temperature is also observed with an addition of the centrally focused ECRH to the low-density and high-Z NBI plasma, suggesting improvement of the ion transport. The results obtained in the high-Z plasma experiments with the high-energy NBI heating indicate that an increase in the direct ion heating power and improvement of the ion transport are essential to the ion temperature rise, and that a high-ion temperature would be obtained as well in hydrogen plasmas with low-energy positive-NBI heating which is planed in near future in LHD. (author)

  17. Negative-ion current density dependence of the surface potential of insulated electrode during negative-ion implantation

    International Nuclear Information System (INIS)

    Tsuji, Hiroshi; Okayama, Yoshio; Toyota, Yoshitaka; Gotoh, Yasuhito; Ishikawa, Junzo; Sakai, Shigeki; Tanjyo, Masayasu; Matsuda, Kouji.

    1994-01-01

    Positive ion implantation has been utilized as the method of impurity injection in ultra-LSI production, but the problem of substrate charging cannot be resolved by conventional charge compensation method. It was forecast that by negative ion implantation, this charging problem can be resolved. Recently the experiment on the negative ion implantation into insulated electrodes was carried out, and the effect of negative ion implantation to this problem was proved. However, the dependence of charged potential on the increase of negative ion current at the time of negative ion implantation is a serious problem in large current negative ion implantation hereafter. The charged potential of insulated conductor substrates was measured by the negative ion implantation using the current up to several mA/cm 2 . The experimental method is explained. Medium current density and high current density negative ion implantation and charged potential are reported. Accordingly in negative ion implantation, if current density is optimized, the negative ion implantation without charging can be realized. (K.I.)

  18. High Energy Density Laboratory Astrophysics

    CERN Document Server

    Lebedev, Sergey V

    2007-01-01

    During the past decade, research teams around the world have developed astrophysics-relevant research utilizing high energy-density facilities such as intense lasers and z-pinches. Every two years, at the International conference on High Energy Density Laboratory Astrophysics, scientists interested in this emerging field discuss the progress in topics covering: - Stellar evolution, stellar envelopes, opacities, radiation transport - Planetary Interiors, high-pressure EOS, dense plasma atomic physics - Supernovae, gamma-ray bursts, exploding systems, strong shocks, turbulent mixing - Supernova remnants, shock processing, radiative shocks - Astrophysical jets, high-Mach-number flows, magnetized radiative jets, magnetic reconnection - Compact object accretion disks, x-ray photoionized plasmas - Ultrastrong fields, particle acceleration, collisionless shocks. These proceedings cover many of the invited and contributed papers presented at the 6th International Conference on High Energy Density Laboratory Astrophys...

  19. Electron density measurements during ion beam transport on Gamble II

    International Nuclear Information System (INIS)

    Weber, B.V.; Hinshelwood, D.D.; Neri, J.M.; Ottinger, P.F.; Rose, D.V.; Stephanakis, S.J.; Young, F.C.

    1999-01-01

    High-sensitivity laser interferometry was used to measure the electron density created when an intense proton beam (100 kA, 1 MeV, 50 ns) from the Gamble II generator was transported through low-pressure gas as part of a project investigating Self-Pinched Transport (SPT) of intense ion beams. This measurement is non-perturbing and sufficiently quantitative to allow benchmarking of codes (particularly IPROP) used to model beam-gas interaction and ion-beam transport. Very high phase sensitivity is required for this measurement. For example, a 100-kA, 1-MeV, 10-cm-radius proton beam with uniform current density has a line-integrated proton density equal to n b L = 3 x 10 13 cm -2 . An equal electron line-density, n e L = n b L, (expected for transport in vacuum) will be detected as a phase shift of the 1.064 microm laser beam of only 0.05degree, or an optical path change of 1.4 x 10 -4 waves (about the size of a hydrogen atom). The time-history of the line-integrated electron density, measured across a diameter of the transport chamber at 43 cm from the input aperture, starts with the proton arrival time and decays differently depending on the gas pressure. The gas conditions included vacuum (10 -4 Torr air), 30 to 220 mTorr He, and 1 Torr air. The measured densities vary by three orders of magnitude, from 10 13 to 10 16 cm -2 for the range of gas pressures investigated. In vacuum, the measured electron densities indicate only co-moving electrons (n e L approximately n b L). In He, when the gas pressure is sufficient for ionization by beam particles and SPT is observed, n e L increases to about 10 n b L. At even higher pressures where electrons contribute to ionization, even higher electron densities are observed with an ionization fraction of about 2%. The diagnostic technique as used on the SPT experiment will be described and a summary of the results will be given. The measurements are in reasonable agreement with theoretical predictions from the IPROP code

  20. Spectroscopy with trapped highly charged ions

    International Nuclear Information System (INIS)

    Beiersdorfer, Peter

    2009-01-01

    We give an overview of atomic spectroscopy performed on electron beam ion traps at various locations throughout the world. Spectroscopy at these facilities contributes to various areas of science and engineering, including but not limited to basic atomic physics, astrophysics, extreme ultraviolet lithography, and the development of density and temperature diagnostics of fusion plasmas. These contributions are accomplished by generating, for example, spectral surveys, making precise radiative lifetime measurements, accounting for radiative power emitted in a given wavelength band, illucidating isotopic effects, and testing collisional-radiative models. While spectroscopy with electron beam ion traps had originally focused on the x-ray emission from highly charged ions interacting with the electron beam, the operating modes of such devices have expanded to study radiation in almost all wavelength bands from the visible to the hard x-ray region; and at several facilities the ions can be studied even in the absence of an electron beam. Photon emission after charge exchange or laser excitation has been observed; and the work is no longer restricted to highly charged ions. Much of the experimental capabilities are unique to electron beam ion traps, and the work performed with these devices cannot be undertaken elsewhere. However, in other areas the work on electron beam ion traps rivals the spectroscopy performed with conventional ion traps or heavy-ion storage rings. The examples we present highlight many of the capabilities of the existing electron beam ion traps and their contributions to physics.

  1. An innovative high-power constant-current pulsed-arc power-supply for a high-density pulsed-arc-plasma ion-source using a LaB6-filament.

    Science.gov (United States)

    Ueno, A; Oguri, H; Ikegami, K; Namekawa, Y; Ohkoshi, K; Tokuchi, A

    2010-02-01

    An innovative high-power constant-current (CC) pulsed-arc (PA) power-supply (PS) indispensable for a high-density PA plasma ion-source using a lanthanum hexaboride (LaB(6)) filament was devised by combining a constant-voltage (CV) PA-PS, which is composed of an insulated gate bipolar transistor (IGBT) switch, a CV direct-current (dc) PS and a 270 mF capacitor with a CC-PA-PS, which is composed of an IGBT-switch, a CC-dc-PS and a 400 microH inductor, through the inductor. The hybrid-CC-PA-PS succeeded in producing a flat arc-pulse with a peak power of 56 kW (400 A x 140 V) and a duty factor of more than 1.5% (600 micros x 25 Hz) for Japan Proton Accelerator Research Complex (J-PARC) H(-) ion-source stably. It also succeeded in shortening the 99% rising-time of the arc-pulse-current to about 20 micros and tilting up or down the arc-pulse-current arbitrarily and almost linearly by changing the setting voltage of its CV-dc-PS.

  2. An innovative high-power constant-current pulsed-arc power-supply for a high-density pulsed-arc-plasma ion-source using a LaB6-filament

    International Nuclear Information System (INIS)

    Ueno, A.; Oguri, H.; Ikegami, K.; Namekawa, Y.; Ohkoshi, K.; Tokuchi, A.

    2010-01-01

    An innovative high-power constant-current (CC) pulsed-arc (PA) power-supply (PS) indispensable for a high-density PA plasma ion-source using a lanthanum hexaboride (LaB 6 ) filament was devised by combining a constant-voltage (CV) PA-PS, which is composed of an insulated gate bipolar transistor (IGBT) switch, a CV direct-current (dc) PS and a 270 mF capacitor with a CC-PA-PS, which is composed of an IGBT-switch, a CC-dc-PS and a 400 μH inductor, through the inductor. The hybrid-CC-PA-PS succeeded in producing a flat arc-pulse with a peak power of 56 kW (400 Ax140 V) and a duty factor of more than 1.5%(600 μsx25 Hz) for Japan Proton Accelerator Research Complex (J-PARC) H - ion-source stably. It also succeeded in shortening the 99% rising-time of the arc-pulse-current to about 20 μs and tilting up or down the arc-pulse-current arbitrarily and almost linearly by changing the setting voltage of its CV-dc-PS.

  3. Photoionization and High Density Gas

    Science.gov (United States)

    Kallman, T.; Bautista, M.; White, Nicholas E. (Technical Monitor)

    2002-01-01

    We present results of calculations using the XSTAR version 2 computer code. This code is loosely based on the XSTAR v.1 code which has been available for public use for some time. However it represents an improvement and update in several major respects, including atomic data, code structure, user interface, and improved physical description of ionization/excitation. In particular, it now is applicable to high density situations in which significant excited atomic level populations are likely to occur. We describe the computational techniques and assumptions, and present sample runs with particular emphasis on high density situations.

  4. High-density multicore fibers

    DEFF Research Database (Denmark)

    Takenaga, K.; Matsuo, S.; Saitoh, K.

    2016-01-01

    High-density single-mode multicore fibers were designed and fabricated. A heterogeneous 30-core fiber realized a low crosstalk of −55 dB. A quasi-single-mode homogeneous 31-core fiber attained the highest core count as a single-mode multicore fiber.......High-density single-mode multicore fibers were designed and fabricated. A heterogeneous 30-core fiber realized a low crosstalk of −55 dB. A quasi-single-mode homogeneous 31-core fiber attained the highest core count as a single-mode multicore fiber....

  5. Ball lightning dynamics and stability at moderate ion densities

    International Nuclear Information System (INIS)

    Morrow, R

    2017-01-01

    A general mechanism is presented for the dynamics and structure of ball lightning and for the maintenance of the ball lightning structure for several seconds. Results are obtained using a spherical geometry for air at atmospheric pressure, by solving the continuity equations for electrons, positive ions and negative ions coupled with Poisson’s equation. A lightning strike can generate conditions in the lightning channel with a majority of positive nitrogen ions, and a minority of negative oxygen ions and electrons. The calculations are initiated with electrons included; however, at the moderate ion densities chosen the electrons are rapidly lost to form negative ions, and after 1 µ s their influence on the ion dynamics is negligible. Further development after 1 µ s is followed using a simpler set of equations involving only positive ions and negative ions, but including ion diffusion. The space-charge electric field generated by the majority positive ions drives them from the centre of the distribution and drives the minority negative ions and electrons towards the centre of the distribution. In the central region the positive and negative ion distributions eventually overlap exactly and their space-charge fields cancel resulting in zero electric field, and the plasma ball formed is quite stable for a number of seconds. The formation of such plasma balls is not critically dependent on the initial diameter of the ion distributions, or the initial density of minority negative ions. The ion densities decrease relatively slowly due to mutual neutralization of positive and negative ions. The radiation from this neutralization process involving positive nitrogen ions and negative oxygen ions is not sufficient to account for the reported luminosity of ball lightning and some other source of luminosity is shown to be required; the plasma ball model used could readily incorporate other ions in order to account for the luminosity and range of colours reported for ball

  6. High energy density lithium batteries

    CERN Document Server

    Aifantis, Katerina E; Kumar, R Vasant

    2010-01-01

    Cell phones, portable computers and other electronic devices crucially depend on reliable, compact yet powerful batteries. Therefore, intensive research is devoted to improving performance and reducing failure rates. Rechargeable lithium-ion batteries promise significant advancement and high application potential for hybrid vehicles, biomedical devices, and everyday appliances. This monograph provides special focus on the methods and approaches for enhancing the performance of next-generation batteries through the use of nanotechnology. Deeper understanding of the mechanisms and strategies is

  7. US Heavy Ion Beam Research for Energy Density Physics Applications and Fusion

    International Nuclear Information System (INIS)

    Davidson, R.C.; Logan, B.G.; Barnard, J.J.; Bieniosek, F.M.; Briggs, R.J.; Callahan D.A.; Kireeff Covo, M.; Celata, C.M.; Cohen, R.H.; Coleman, J.E.; Debonnel, C.S.; Grote, D.P.; Efthimiom, P.C.; Eylon, S.; Friedman, A.; Gilson, E.P.; Grisham, L.R.; Henestroza, E.; Kaganovich, I.D.; Kwan, J.W.; Lee, E.P.; Lee, W.W.; Leitner, M.; Lund, S.M.; Meier, W.R.; Molvik, A.W.; Olson, C.L.; Penn, G.E.; Qin, H.; Roy, P.K.; Rose, D.V.; Sefkow, A.; Seidl, P.A.; Sharp, W.M.; Startsev, E.A.; Tabak, M.; Thoma, C.; Vay, J-L; Wadron, W.L.; Wurtele, J.S.; Welch, D.R.; Westenskow, G.A.; Yu, S.S.

    2005-01-01

    Key scientific results from recent experiments, modeling tools, and heavy ion accelerator research are summarized that explore ways to investigate the properties of high energy density matter in heavy-ion-driven targets, in particular, strongly-coupled plasmas at 0.01 to 0.1 times solid density for studies of warm dense matter, which is a frontier area in high energy density physics. Pursuit of these near-term objectives has resulted in many innovations that will ultimately benefit heavy ion inertial fusion energy. These include: neutralized ion beam compression and focusing, which hold the promise of greatly improving the stage between the accelerator and the target chamber in a fusion power plant; and the Pulse Line Ion Accelerator (PLIA), which may lead to compact, low-cost modular linac drivers

  8. Determination of gas phase protein ion densities via ion mobility analysis with charge reduction.

    Science.gov (United States)

    Maisser, Anne; Premnath, Vinay; Ghosh, Abhimanyu; Nguyen, Tuan Anh; Attoui, Michel; Hogan, Christopher J

    2011-12-28

    We use a charge reduction electrospray (ESI) source and subsequent ion mobility analysis with a differential mobility analyzer (DMA, with detection via both a Faraday cage electrometer and a condensation particle counter) to infer the densities of single and multiprotein ions of cytochrome C, lysozyme, myoglobin, ovalbumin, and bovine serum albumin produced from non-denaturing (20 mM aqueous ammonium acetate) and denaturing (1 : 49.5 : 49.5, formic acid : methanol : water) ESI. Charge reduction is achieved through use of a Po-210 radioactive source, which generates roughly equal concentrations of positive and negative ions. Ions produced by the source collide with and reduce the charge on ESI generated drops, preventing Coulombic fissions, and unlike typical protein ESI, leading to gas-phase protein ions with +1 to +3 excess charges. Therefore, charge reduction serves to effectively mitigate any role that Coulombic stretching may play on the structure of the gas phase ions. Density inference is made via determination of the mobility diameter, and correspondingly the spherical equivalent protein volume. Through this approach it is found that for both non-denaturing and denaturing ESI-generated ions, gas-phase protein ions are relatively compact, with average densities of 0.97 g cm(-3) and 0.86 g cm(-3), respectively. Ions from non-denaturing ESI are found to be slightly more compact than predicted from the protein crystal structures, suggesting that low charge state protein ions in the gas phase are slightly denser than their solution conformations. While a slight difference is detected between the ions produced with non-denaturing and denaturing ESI, the denatured ions are found to be much more dense than those examined previously by drift tube mobility analysis, in which charge reduction was not employed. This indicates that Coulombic stretching is typically what leads to non-compact ions in the gas-phase, and suggests that for gas phase

  9. Distributions of the ion temperature, ion pressure, and electron density over the current sheet surface

    Energy Technology Data Exchange (ETDEWEB)

    Kyrie, N. P., E-mail: kyrie@fpl.gpi.ru; Markov, V. S., E-mail: natalya.kyrie@yandex.ru; Frank, A. G.; Vasilkov, D. G.; Voronova, E. V. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

    2016-06-15

    The distributions of the ion temperature, ion pressure, and electron density over the width (the major transverse dimension) of the current sheet have been studied for the first time. The current sheets were formed in discharges in argon and helium in 2D and 3D magnetic configurations. It is found that the temperature of argon ions in both 2D and 3D magnetic configurations is almost uniform over the sheet width and that argon ions are accelerated by the Ampère force. In contrast, the distributions of the electron density and the temperature of helium ions are found to be substantially nonuniform. As a result, in the 2D magnetic configuration, the ion pressure gradient across the sheet width makes a significant contribution (comparable with the Ampère force) to the acceleration of helium ions, whereas in the 3D magnetic configuration, the Ampère force is counterbalanced by the pressure gradient.

  10. Distributions of the ion temperature, ion pressure, and electron density over the current sheet surface

    International Nuclear Information System (INIS)

    Kyrie, N. P.; Markov, V. S.; Frank, A. G.; Vasilkov, D. G.; Voronova, E. V.

    2016-01-01

    The distributions of the ion temperature, ion pressure, and electron density over the width (the major transverse dimension) of the current sheet have been studied for the first time. The current sheets were formed in discharges in argon and helium in 2D and 3D magnetic configurations. It is found that the temperature of argon ions in both 2D and 3D magnetic configurations is almost uniform over the sheet width and that argon ions are accelerated by the Ampère force. In contrast, the distributions of the electron density and the temperature of helium ions are found to be substantially nonuniform. As a result, in the 2D magnetic configuration, the ion pressure gradient across the sheet width makes a significant contribution (comparable with the Ampère force) to the acceleration of helium ions, whereas in the 3D magnetic configuration, the Ampère force is counterbalanced by the pressure gradient.

  11. Characterization of the internal ion environment of biofilms based on charge density and shape of ion.

    Science.gov (United States)

    Kurniawan, Andi; Tsuchiya, Yuki; Eda, Shima; Morisaki, Hisao

    2015-12-01

    Biofilm polymers contain both electrically positively and negatively charged sites. These charged sites enable the biofilm to trap and retain ions leading to an important role of biofilm such as nutrient recycling and pollutant purification. Much work has focused on the ion-exchange capacity of biofilms, and they are known to adsorb ions through an exchange mechanism between the ions in solution and the ions adsorbed to the charged sites on the biofilm polymer. However, recent studies suggest that the adsorption/desorption behavior of ions in a biofilm cannot be explained solely by this ion exchange mechanism. To examine the possibility that a substantial amount of ions are held in the interstitial region of the biofilm polymer by an electrostatic interaction, intact biofilms formed in a natural environment were immersed in distilled water and ion desorption was investigated. All of the detected ion species were released from the biofilms over a short period of time, and very few ions were subsequently released over more time, indicating that the interstitial region of biofilm polymers is another ion reserve. The extent of ion retention in the interstitial region of biofilms for each ion can be determined largely by charge density, |Z|/r, where |Z| is the ion valence as absolute value and r is the ion radius. The higher |Z|/r value an ion has, the stronger it is retained in the interstitial region of biofilms. Ion shape is also a key determinant of ion retention. Spherical and non-spherical ions have different correlations between the condensation ratio and |Z|/r. The generality of these findings were assured by various biofilm samples. Thus, the internal regions of biofilms exchange ions dynamically with the outside environment. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. High density fuel storage rack

    International Nuclear Information System (INIS)

    Zezza, L.J.

    1980-01-01

    High storage density for spent nuclear fuel assemblies in a pool achieved by positioning fuel storage cells of high thermal neutron absorption materials in an upright configuration in a rack. The rack holds the cells at required pitch. Each cell carries an internal fuel assembly support, and most cells are vertically movable in the rack so that they rest on the pool bottom. Pool water circulation through the cells and around the fuel assemblies is permitted by circulation openings at the top and bottom of the cells above and below the fuel assemblies

  13. Profiles of plasma parameters and density of negative hydrogen ions by laser detachment measurements in RF-driven ion sources

    International Nuclear Information System (INIS)

    Christ-Koch, Sina

    2007-01-01

    This work shows the application of the Laserdetachment method for spatially resolved measurements of negative Hydrogen/Deuterium ion density. It was applied on a high power low pressure RF-driven ion source. The Laser detachment method is based on the measurement of electron currents on a positively biased Langmuir probe before and during/after a laser pulse. The density ratio of negative ions to electrons can be derived from the ratio of currents to the probe. The absolute density of negative ions can be obtained when the electron density is measured with the standard Langmuir probe setup. Measurements with the Langmuir probe additionally yield information about the floating and plasma potential, the electron temperature and the density of positive ions. The Laser detachment setup had to be adapted to the special conditions of the RF-driven source. In particular the existence of RF fields (1 MHz), high source potential (-20 kV), magnetic fields (∝ 7 mT) and caesium inside the source had to be considered. The density of negative ions could be identified in the range of n(H - )=1.10 17 1/m 3 , which is in the same order of magnitude as the electron density. Only the application of the Laser detachment method with the Langmuir probe measurements will yield spatially resolved plasma parameters and H- density profiles. The influence of diverse external parameters, such as pressure, RF-power, magnetic fields on the plasma parameters and their profiles were studied and explained. Hence, the measurements lead to a detailed understanding of the processes inside the source. (orig.)

  14. Double trouble at high density:

    DEFF Research Database (Denmark)

    Gergs, André; Palmqvist, Annemette; Preuss, Thomas G

    2014-01-01

    Population size is often regulated by negative feedback between population density and individual fitness. At high population densities, animals run into double trouble: they might concurrently suffer from overexploitation of resources and also from negative interference among individuals...... regardless of resource availability, referred to as crowding. Animals are able to adapt to resource shortages by exhibiting a repertoire of life history and physiological plasticities. In addition to resource-related plasticity, crowding might lead to reduced fitness, with consequences for individual life...... history. We explored how different mechanisms behind resource-related plasticity and crowding-related fitness act independently or together, using the water flea Daphnia magna as a case study. For testing hypotheses related to mechanisms of plasticity and crowding stress across different biological levels...

  15. Experimental observations of anomalous potential drops over ion density cavities

    International Nuclear Information System (INIS)

    Bohm, M.

    1991-08-01

    Experiments are reported showing the plasma potential response when a step voltage is applied over the plasma column between the two plasma sources in a triple plasma machine. The time resolution is sufficient to resolve potential variations caused essentially by the electron motion, and two independent probe methods are used to obtain this time resolution. Depending on the initial conditions two different responses were observed on the time scale of the electron motion. When the initial ion density varies along the plasma column and has a local minimum (that is, forms an ion density cavity), the applied potential drop becomes distributed over the cavity after a few electron transit times. Later the profile steepens to a double layer on the time scale of the ion motion. The width of the cavity is comparable to the length of the plasma column. When the initial density is axially uniform, most of the potential drop instead concentrates to a narrow region at the low potential end of the plasma column after a few electron transit times. On the time scale of the ion motion this potential drop begins to propagate into the plasma as a double layer. The results obtained are consistent with those from numerical simulations with similar boundary conditions. Further experiments are necessary to get conclusive insight into the voltage supporting capability of an ion density cavity. (au) (34 refs.)

  16. Physical mechanisms leading to high currents of highly charged ions in laser-driven ion sources

    International Nuclear Information System (INIS)

    Haseroth, Helmut; Hora, Heinrich; Regensburg Inst. of Tech.

    1996-01-01

    Heavy ion sources for the big accelerators, for example, the LHC, require considerably more ions per pulse during a short time than the best developed classical ion source, the electron cyclotron resonance (ECR) provides; thus an alternative ion source is needed. This can be expected from laser-produced plasmas, where dramatically new types of ion generation have been observed. Experiments with rather modest lasers have confirmed operation with one million pulses of 1 Hz, and 10 11 C 4+ ions per pulse reached 2 GeV/u in the Dubna synchrotron. We review here the complexities of laser-plasma interactions to underline the unique and extraordinary possibilities that the laser ion source offers. The complexities are elaborated with respect to keV and MeV ion generation, nonlinear (ponderomotive) forces, self-focusing, resonances and ''hot'' electrons, parametric instabilities, double-layer effects, and the few ps stochastic pulsation (stuttering). Recent experiments with the laser ion source have been analyzed to distinguish between the ps and ns interaction, and it was discovered that one mechanism of highly charged ion generation is the electron impact ionization (EII) mechanism, similar to the ECR, but with so much higher plasma densities that the required very large number of ions per pulse are produced. (author)

  17. Physical mechanisms leading to high currents of highly charged ions in laser-driven ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Haseroth, Helmut [European Organization for Nuclear Research, Geneva (Switzerland); Hora, Heinrich [New South Wales Univ., Kensington, NSW (Australia)]|[Regensburg Inst. of Tech. (Germany). Anwenderzentrum

    1996-12-31

    Heavy ion sources for the big accelerators, for example, the LHC, require considerably more ions per pulse during a short time than the best developed classical ion source, the electron cyclotron resonance (ECR) provides; thus an alternative ion source is needed. This can be expected from laser-produced plasmas, where dramatically new types of ion generation have been observed. Experiments with rather modest lasers have confirmed operation with one million pulses of 1 Hz, and 10{sup 11} C{sup 4+} ions per pulse reached 2 GeV/u in the Dubna synchrotron. We review here the complexities of laser-plasma interactions to underline the unique and extraordinary possibilities that the laser ion source offers. The complexities are elaborated with respect to keV and MeV ion generation, nonlinear (ponderomotive) forces, self-focusing, resonances and ``hot`` electrons, parametric instabilities, double-layer effects, and the few ps stochastic pulsation (stuttering). Recent experiments with the laser ion source have been analyzed to distinguish between the ps and ns interaction, and it was discovered that one mechanism of highly charged ion generation is the electron impact ionization (EII) mechanism, similar to the ECR, but with so much higher plasma densities that the required very large number of ions per pulse are produced. (author).

  18. A high-energy electron beam ion trap for production of high-charge high-Z ions

    International Nuclear Information System (INIS)

    Knapp, D.A.; Marrs, R.E.; Elliott, S.R.; Magee, E.W.; Zasadzinski, R.

    1993-01-01

    We have developed a new high-energy electron beam ion trap, the first laboratory source of low-energy, few-electron, high-Z ions. We describe the device and report measurements of its performance, including the electron beam diameter, current density and energy, and measurements of the ionization balance for several high-Z elements in the trap. This device opens up a wide range of possible experiments in atomic physics, plasma physics, and nuclear physics. (orig.)

  19. Ultralow energy ion beam surface modification of low density polyethylene.

    Science.gov (United States)

    Shenton, Martyn J; Bradley, James W; van den Berg, Jaap A; Armour, David G; Stevens, Gary C

    2005-12-01

    Ultralow energy Ar+ and O+ ion beam irradiation of low density polyethylene has been carried out under controlled dose and monoenergetic conditions. XPS of Ar+-treated surfaces exposed to ambient atmosphere show that the bombardment of 50 eV Ar+ ions at a total dose of 10(16) cm(-2) gives rise to very reactive surfaces with oxygen incorporation at about 50% of the species present in the upper surface layer. Using pure O+ beam irradiation, comparatively low O incorporation is achieved without exposure to atmosphere (approximately 13% O in the upper surface). However, if the surface is activated by Ar+ pretreatment, then large oxygen contents can be achieved under subsequent O+ irradiation (up to 48% O). The results show that for very low energy (20 eV) oxygen ions there is a dose threshold of about 5 x 10(15) cm(-2) before surface oxygen incorporation is observed. It appears that, for both Ar+ and O+ ions in this regime, the degree of surface modification is only very weakly dependent on the ion energy. The results suggest that in the nonequilibrium plasma treatment of polymers, where the ion flux is typically 10(18) m(-2) s(-1), low energy ions (<50 eV) may be responsible for surface chemical modification.

  20. Freestanding rGO-SWNT-STN Composite Film as an Anode for Li Ion Batteries with High Energy and Power Densities

    Directory of Open Access Journals (Sweden)

    Taeseup Song

    2015-12-01

    Full Text Available Freestanding Si-Ti-Ni alloy particles/reduced graphene oxide/single wall carbon nanotube composites have been prepared as an anode for lithium ion batteries via a simple filtration method. This composite electrode showed a 9% increase in reversible capacity, a two-fold higher cycle retention at 50 cycles and a two-fold higher rate capability at 2 C compared to pristine Si-Ti-Ni (STN alloy electrodes. These improvements were attributed to the suppression of the pulverization of the STN active material by the excellent mechanical properties of the reduced graphene oxide-single wall carbon nanotube networks and the enhanced kinetics associated with both electron and Li ion transport.

  1. Production of ultrahigh ion current densities at skin-layer subrelativistic laser-plasma interaction

    Energy Technology Data Exchange (ETDEWEB)

    Badziak, J [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Glowacz, S [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Jablonski, S [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Parys, P [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Wolowski, J [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Hora, H [Department of Theoretical Physics, University of New South Wales, Sydney (Australia); Krasa, J [Institute of Physics, ASCR, Prague (Czech Republic); Laska, L [Institute of Physics, ASCR, Prague (Czech Republic); Rohlena, K [Institute of Physics, ASCR, Prague (Czech Republic)

    2004-12-01

    Some applications of fast ions driven by a short ({<=}1 ps) laser pulse (e.g. fast ignition of ICF targets, x-ray laser pumping, laboratory astrophysics research or some nuclear physics experiments) require ion beams of picosecond (or shorter) time durations and of very high ion current densities ({approx}10{sup 10} A cm{sup -2} or higher). A possible way of producing ion beams with such extreme parameters is ballistic focusing of fast ions generated by a target normal sheath acceleration (TNSA) mechanism at relativistic laser intensities. In this paper we discuss another method, where the production of short-pulse ion beams of ultrahigh current densities is possible in a planar geometry at subrelativistic laser intensities and at a low energy ({<=}1 J) of the laser pulse. This method-referred to as skin-layer ponderomotive acceleration (S-LPA)-uses strong ponderomotive forces induced at the skin-layer interaction of a short laser pulse with a proper preplasma layer in front of a solid target. The basic features of the high-current ion generation by S-LPA were investigated using a simplified theory, numerical hydrodynamic simulations and measurements. The experiments were performed with subjoule 1 ps laser pulses interacting with massive or thin foil targets at intensities of up to 2 x 10{sup 17} W cm{sup -2}. It was found that both in the backward and forward directions highly collimated high-density ion beams (plasma blocks) with current densities at the ion source (close to the target) approaching 10{sup 10} A cm{sup -2} are produced, in accordance with the theory and numerical calculations. These ion current densities were found to be comparable to (or even higher than) those estimated from recent short-pulse TNSA experiments with relativistic laser intensities. Apart from the simpler physics of the laser-plasma interaction, the advantage of the considered method is the low energy of the driving laser pulses allowing the production of ultrahigh-current-density

  2. Importing low-density ideas to high-density revitalisation

    DEFF Research Database (Denmark)

    Arnholtz, Jens; Ibsen, Christian Lyhne; Ibsen, Flemming

    2016-01-01

    Why did union officials from a high-union-density country like Denmark choose to import an organising strategy from low-density countries such as the US and the UK? Drawing on in-depth interviews with key union officials and internal documents, the authors of this article argue two key points. Fi...

  3. 3.0 V High Energy Density Symmetric Sodium-Ion Battery: Na4V2(PO4)3∥Na3V2(PO4)3.

    Science.gov (United States)

    Yao, Xuhui; Zhu, Zixuan; Li, Qi; Wang, Xuanpeng; Xu, Xiaoming; Meng, Jiashen; Ren, Wenhao; Zhang, Xinhe; Huang, Yunhui; Mai, Liqiang

    2018-03-28

    Symmetric sodium-ion batteries (SIBs) are considered as promising candidates for large-scale energy storage owing to the simplified manufacture and wide abundance of sodium resources. However, most symmetric SIBs suffer from suppressed energy density. Here, a superior congeneric Na 4 V 2 (PO 4 ) 3 anode is synthesized via electrochemical preintercalation, and a high energy density symmetric SIB (Na 3 V 2 (PO 4 ) 3 as a cathode and Na 4 V 2 (PO 4 ) 3 as an anode) based on the deepened redox couple of V 4+ /V 2+ is built for the first time. When measured in half cell, both electrodes show stabilized electrochemical performance (over 3000 cycles). The symmetric SIBs exhibit an output voltage of 3.0 V and a cell-level energy density of 138 W h kg -1 . Furthermore, the sodium storage mechanism under the expanded measurement range of 0.01-3.9 V is disclosed through an in situ X-ray diffraction technique.

  4. Electrostatic lens to focus an ion beam to uniform density

    International Nuclear Information System (INIS)

    Johnson, C.H.

    1977-01-01

    A focusing lens for an ion beam having a gaussian or similar density profile is described. The lens is constructed to provide an inner zero electrostatic field, and an outer electrostatic field such that ions entering this outer field are deflected by an amount that is a function of their distance from the edge of the inner field. The result is a beam that focuses to uniform density in a manner analogous to that of an optical ring lens. In one embodiment, a conically-shaped network of fine wires is enclosed within a cylindrical anode. The wire net together with the anode produces a voltage field that re-directs the outer particles of the beam while the axial particles pass undeflected through a zero field inside the wire net. The result is a focused beam having a uniform intensity over a given target area and at a given distance from the lens

  5. High baryon and energy densities achievable in heavy-ion collisions at √{sN N}=39 GeV

    Science.gov (United States)

    Ivanov, Yu. B.; Soldatov, A. A.

    2018-02-01

    Baryon and energy densities, which are reached in central Au+Au collisions at collision energy of √{sN N}= 39 GeV, are estimated within the model of three-fluid dynamics. It is shown that the initial thermalized mean proper baryon and energy densities in a sizable central region approximately are nB/n0≈ 10 and ɛ ≈ 40 GeV/fm3, respectively. The study indicates that the deconfinement transition at the stage of interpenetration of colliding nuclei makes the system quite opaque. The final fragmentation regions in these collisions are formed not only by primordial fragmentation fireballs, i.e., the baryon-rich matter passed through the interaction region (containing approximately 30% of the total baryon charge), but also by the baryon-rich regions of the central fireball pushed out to peripheral rapidities by the subsequent almost one-dimensional expansion of the central fireball along the beam direction.

  6. Error estimation and parameter dependence of the calculation of the fast ion distribution function, temperature, and density using data from the KF1 high energy neutral particle analyzer on Joint European Torus

    International Nuclear Information System (INIS)

    Schlatter, Christian; Testa, Duccio; Cecconello, Marco; Murari, Andrea; Santala, Marko

    2004-01-01

    Joint European Torus high energy neutral particle analyzer measures the flux of fast neutrals originating from the plasma core. From this data, the fast ion distribution function f i fast , temperature T i,perpendicular fast , and density n i fast are derived using knowledge of various plasma parameters and of the cross section for the required atomic processes. In this article, a systematic sensitivity study of the effect of uncertainties in these quantities on the evaluation of the neutral particle analyzer f i fast , T i,perpendicular fast , and n i fast is reported. The dominant parameter affecting n i fast is the impurity confinement time and therefore a reasonable estimate of this quantity is necessary to reduce the uncertainties in n i fast below 50%. On the other hand, T i,perpendicular fast is much less sensitive and can certainly be provided with an accuracy of better than 10%

  7. ECRIS sources for highly charged ions

    International Nuclear Information System (INIS)

    Geller, R.

    1991-01-01

    The so-called Philips ionization gauge ion sources (PIGIS) were used until quite recently in heavy ion accelerators so multiply charged ions could only be obtained by incorporating a stripper to remove electrons. Electron cyclotron resonance ion sources (ECRIS) now dominate as they produce more highly charged ions. (orig.)

  8. Production of highly ionized recoil ions in heavy ion impact

    International Nuclear Information System (INIS)

    Tawara, H.; Tonuma, T.; Be, S.H.; Shibata, H.; Kase, M.; Kambara, T.; Kumagai, H.; Kohno, I.

    1985-01-01

    The production mechanisms of highly ionized recoil ions in energetic, highly charged heavy ion impact are compared with those in photon and electron impact. In addition to the innershell ionization processes which are important in photon and electron impact, the electron transfer processes are found to play a key role in heavy ion impact. In molecular targets are also observed highly ionized monoatomic ions which are believed to be produced through production of highly ionized molecular ions followed by prompt dissociation. The observed N 6+ ions produced in 1.05MeV/amu Ar 12+ ions on N 2 molecules are produced through, for example, N 2 12+ *→N 6+ +N 6+ process. (author)

  9. Searching for high baryon density at the AGS with ARC

    International Nuclear Information System (INIS)

    Kahana, S.H.; Schlagel, T.J.; Pang, Y.

    1993-08-01

    A relativistic cascade ARC is used to analyse heavy ion experiments at the AGS. In particular predictions from ARC for Au on Au at 11.6 GeV/c have proved to be remarkably accurate. Going to lower energies and inserting a phenomenological equation of state into the cascade should lead to information about the interesting region of high baryon density

  10. Determination of Hydrogen Density by Swift Heavy Ions.

    Science.gov (United States)

    Xu, Ge; Barriga-Carrasco, M D; Blazevic, A; Borovkov, B; Casas, D; Cistakov, K; Gavrilin, R; Iberler, M; Jacoby, J; Loisch, G; Morales, R; Mäder, R; Qin, S-X; Rienecker, T; Rosmej, O; Savin, S; Schönlein, A; Weyrich, K; Wiechula, J; Wieser, J; Xiao, G Q; Zhao, Y T

    2017-11-17

    A novel method to determine the total hydrogen density and, accordingly, a precise plasma temperature in a lowly ionized hydrogen plasma is described. The key to the method is to analyze the energy loss of swift heavy ions interacting with the respective bound and free electrons of the plasma. A slowly developing and lowly ionized hydrogen theta-pinch plasma is prepared. A Boltzmann plot of the hydrogen Balmer series and the Stark broadening of the H_{β} line preliminarily defines the plasma with a free electron density of (1.9±0.1)×10^{16}  cm^{-3} and a free electron temperature of 0.8-1.3 eV. The temperature uncertainty results in a wide hydrogen density, ranging from 2.3×10^{16} to 7.8×10^{18}  cm^{-3}. A 108 MHz pulsed beam of ^{48}Ca^{10+} with a velocity of 3.652  MeV/u is used as a probe to measure the total energy loss of the beam ions. Subtracting the calculated energy loss due to free electrons, the energy loss due to bound electrons is obtained, which linearly depends on the bound electron density. The total hydrogen density is thus determined as (1.9±0.7)×10^{17}  cm^{-3}, and the free electron temperature can be precisely derived as 1.01±0.04  eV. This method should prove useful in many studies, e.g., inertial confinement fusion or warm dense matter.

  11. High density energy storage capacitor

    International Nuclear Information System (INIS)

    Whitham, K.; Howland, M.M.; Hutzler, J.R.

    1979-01-01

    The Nova laser system will use 130 MJ of capacitive energy storage and have a peak power capability of 250,000 MW. This capacitor bank is a significant portion of the laser cost and requires a large portion of the physical facilities. In order to reduce the cost and volume required by the bank, the Laser Fusion Program funded contracts with three energy storage capacitor producers: Aerovox, G.E., and Maxwell Laboratories, to develop higher energy density, lower cost energy storage capacitors. This paper describes the designs which resulted from the Aerovox development contract, and specifically addresses the design and initial life testing of a 12.5 kJ, 22 kV capacitor with a density of 4.2 J/in 3 and a projected cost in the range of 5 cents per joule

  12. Density changes in amorphous Pd80Si20 during low temperature ion irradiation

    International Nuclear Information System (INIS)

    Schumacher, G.; Birtcher, R.C.; Rehn, L.E.

    1994-11-01

    Density changes in amorphous Pd 80 Si 20 during ion irradiation below 100K were detected by in situ HVEM measurements of the changes in specimen length as a function of ion fluence. A decrease in mass density as a function of the ion fluence was observed. The saturation value of the change in mass density was determined to be approximately -1.2%

  13. High-density lipoprotein cholesterol: How High

    Directory of Open Access Journals (Sweden)

    G Rajagopal

    2012-01-01

    Full Text Available The high-density lipoprotein cholesterol (HDL-C is considered anti-atherogenic good cholesterol. It is involved in reverse transport of lipids. Epidemiological studies have found inverse relationship of HDL-C and coronary heart disease (CHD risk. When grouped according to HDL-C, subjects having HDL-C more than 60 mg/dL had lesser risk of CHD than those having HDL-C of 40-60 mg/dL, who in turn had lesser risk than those who had HDL-C less than 40 mg/dL. No upper limit for beneficial effect of HDL-C on CHD risk has been identified. The goals of treating patients with low HDL-C have not been firmly established. Though many drugs are known to improve HDL-C concentration, statins are proven to improve CHD risk and mortality. Cholesteryl ester transfer protein (CETP is involved in metabolism of HDL-C and its inhibitors are actively being screened for clinical utility. However, final answer is still awaited on CETP-inhibitors.

  14. Fluorescent Fe K Emission from High Density Accretion Disks

    Science.gov (United States)

    Bautista, Manuel; Mendoza, Claudio; Garcia, Javier; Kallman, Timothy R.; Palmeri, Patrick; Deprince, Jerome; Quinet, Pascal

    2018-06-01

    Iron K-shell lines emitted by gas closely orbiting black holes are observed to be grossly broadened and skewed by Doppler effects and gravitational redshift. Accordingly, models for line profiles are widely used to measure the spin (i.e., the angular momentum) of astrophysical black holes. The accuracy of these spin estimates is called into question because fitting the data requires very high iron abundances, several times the solar value. Meanwhile, no plausible physical explanation has been proffered for why these black hole systems should be so iron rich. The most likely explanation for the super-solar iron abundances is a deficiency in the models, and the leading candidate cause is that current models are inapplicable at densities above 1018 cm-3. We study the effects of high densities on the atomic parameters and on the spectral models for iron ions. At high densities, Debye plasma can affect the effective atomic potential of the ions, leading to observable changes in energy levels and atomic rates with respect to the low density case. High densities also have the effec of lowering energy the atomic continuum and reducing the recombination rate coefficients. On the spectral modeling side, high densities drive level populations toward a Boltzman distribution and very large numbers of excited atomic levels, typically accounted for in theoretical spectral models, may contribute to the K-shell spectrum.

  15. States of high energy density

    International Nuclear Information System (INIS)

    Murray, M.

    1988-02-01

    The transverse energy, E/sub tau/ spectra for O 16 and S 32 incident for various elements at 200 GeVnucleon are shown. The target and projectile dependencies of the data are discussed. The energy density achieved is estimated. For O 16 on Tungsten the multiplicity spectrum is also presented as well as the pseudorapidity spectra as a function of the transverse energy. The multiplicity cross section dσdN as measured in the backward hemisphere (0.9 < /eta/ < 2.9/ is found to be very similar in shape to the transverse energy distribution dσdE/tau/ reflecting the particular geometry of nucleus nucleus nucleus collisions. The dependence on the atomic mass of the target, A/sub tau/ and projectile A/sub p/ is not what one would expect from naive considerations

  16. High Energy Density Physics and Exotic Acceleration Schemes

    International Nuclear Information System (INIS)

    Cowan, T.; Colby, E.

    2005-01-01

    The High Energy Density and Exotic Acceleration working group took as our goal to reach beyond the community of plasma accelerator research with its applications to high energy physics, to promote exchange with other disciplines which are challenged by related and demanding beam physics issues. The scope of the group was to cover particle acceleration and beam transport that, unlike other groups at AAC, are not mediated by plasmas or by electromagnetic structures. At this Workshop, we saw an impressive advancement from years past in the area of Vacuum Acceleration, for example with the LEAP experiment at Stanford. And we saw an influx of exciting new beam physics topics involving particle propagation inside of solid-density plasmas or at extremely high charge density, particularly in the areas of laser acceleration of ions, and extreme beams for fusion energy research, including Heavy-ion Inertial Fusion beam physics. One example of the importance and extreme nature of beam physics in HED research is the requirement in the Fast Ignitor scheme of inertial fusion to heat a compressed DT fusion pellet to keV temperatures by injection of laser-driven electron or ion beams of giga-Amp current. Even in modest experiments presently being performed on the laser-acceleration of ions from solids, mega-amp currents of MeV electrons must be transported through solid foils, requiring almost complete return current neutralization, and giving rise to a wide variety of beam-plasma instabilities. As keynote talks our group promoted Ion Acceleration (plenary talk by A. MacKinnon), which historically has grown out of inertial fusion research, and HIF Accelerator Research (invited talk by A. Friedman), which will require impressive advancements in space-charge-limited ion beam physics and in understanding the generation and transport of neutralized ion beams. A unifying aspect of High Energy Density applications was the physics of particle beams inside of solids, which is proving to

  17. Production of highly charged ion beams from ECR ion sources

    International Nuclear Information System (INIS)

    Xie, Z.Q.

    1997-09-01

    Electron Cyclotron Resonance (ECR) ion source development has progressed with multiple-frequency plasma heating, higher mirror magnetic fields and better technique to provide extra cold electrons. Such techniques greatly enhance the production of highly charged ions from ECR ion sources. So far at cw mode operation, up to 300 eμA of O 7+ and 1.15 emA of O 6+ , more than 100 eμA of intermediate heavy ions for charge states up to Ar 13+ , Ca 13+ , Fe 13+ , Co 14+ and Kr 18+ , and tens of eμA of heavy ions with charge states to Kr 26+ , Xe 28+ , Au 35+ , Bi 34+ and U 34+ have been produced from ECR ion sources. At an intensity of at least 1 eμA, the maximum charge state available for the heavy ions are Xe 36+ , Au 46+ , Bi 47+ and U 48+ . An order of magnitude enhancement for fully stripped argon ions (I ≥ 60 enA) also has been achieved. This article will review the ECR ion source progress and discuss key requirement for ECR ion sources to produce the highly charged ion beams

  18. Ion transition heights from topside electron density profiles

    International Nuclear Information System (INIS)

    Titheridge, J.E.

    1976-01-01

    Theoretical electron density profiles are calculated for the topside ionosphere to determine the major factors controlling the profile shape. Only the mean temperature, the vertical temperature gradient and the O + /H + ion transition height are important. Vertical proton fluxes alter the ion transition height but have no other effect on the profile shape. Diffusive equilibrium profiles including only these three effects fit observed profiles, at all latitudes, to within experimental accuracy. Values of plasma temperature, temperature gradient and ion transition height hsub(T) were determined by fitting theoretical models to 60,000 experimental profiles obtained from Alouette 1 ionograms, at latitudes of 75 0 S to 85 0 N near solar minimum. Inside the plasmasphere hsub(T) varies from about 500 km on winter nights to 850 km on summer days. Diurnal variations are caused primarily by the production and loss of O + in the ionosphere. The approximately constant winter night value of hsub(T) is close to the level for chemical equilibrium. In summer hsub(T) is always above the equilibrium level, giving a continual production of protons which travel along lines of force to aid in maintaining the conjugate winter night ionosphere. Outside the plasmasphere hsub(T) is 300 to 600 km above the equilibrium level at all times. This implies a continual near-limiting upwards flux of protons which persists down to latitudes of about 60 0 at night and 50 0 during the day. (author)

  19. Characteristics of a High Current Helicon Ion Source With High Monatomic Fraction

    International Nuclear Information System (INIS)

    Jung, Hwa-Dong; Chung, Kyoung-Jae; Hwang, Yong-Seok

    2006-01-01

    Applications of neutron need compact and high yield neutron sources as well as very intense neutron sources from giant devices such as accelerators. Ion source based neutron sources using nuclear fusion reactions such as D(d, 3He)n, D(t, 4He)n can meet the requirements. This type of neutron generators can be simply composed of an ion source and a target. High-performance neutron generators with high yield require ion sources with high beam current, high monatomic fraction and long lifetime. Helicon ion source can meet these requirements. To make high current ion source, characteristics of helicon plasma such as high plasma density can be utilized. Moreover, efficient plasma heating with RF power lead high fraction of monatomic ion beam. Here, Characteristics of helicon plasma sources are described. Design and its performances of a helicon ion source are presented

  20. Rechargeable Lithium-Ion Based Batteries and Thermal Management for Airborne High Energy Electric Lasers (Preprint)

    National Research Council Canada - National Science Library

    Fellner, Joseph P; Miller, Ryan M; Shanmugasundaram, Venkatrama

    2006-01-01

    ...). Rechargeable lithium-ion polymer batteries, for applications such as remote-control aircraft, are achieving simultaneously high energy density and high power density (>160 Whr/kg at > 1.0 kW/kg...

  1. High density harp for SSCL linac

    International Nuclear Information System (INIS)

    Fritsche, C.T.; Krogh, M.L.; Crist, C.E.

    1993-01-01

    AlliedSignal Inc., Kansas City Division, and the Superconducting Super Collider Laboratory (SSCL) are collaboratively developing a high density harp for the SSCL linac. This harp is designed using hybrid microcircuit (HMC) technology to obtain a higher wire density than previously available. The developed harp contains one hundred twenty-eight 33-micron-diameter carbon wires on 0.38-mm centers. The harp features an onboard broken wire detection circuit. Carbon wire preparation and attachment processes were developed. High density surface mount connectors were located. The status of high density harp development will be presented along with planned future activities

  2. High density harp for SSCL linac

    International Nuclear Information System (INIS)

    Fritsche, C.T.; Krogh, M.L.

    1993-05-01

    AlliedSignal Inc., Kansas City Division, and the Superconducting Super Collider Laboratory (SSCL) are collaboratively developing a high density harp for the SSCL linac. This harp is designed using hybrid microcircuit (HMC) technology to obtain a higher wire density than previously available. The developed harp contains one hundred twenty-eight 33-micron-diameter carbon wires on 0.38-mm centers. The harp features an onboard broken wire detection circuit. Carbon wire preparation and attachment processes were developed. High density surface mount connectors were located. The status of high density harp development will be presented along with planned future activities

  3. Space-charge compensation of highly charged ion beam from laser ion source

    International Nuclear Information System (INIS)

    Kondrashev, S.A.; Collier, J.; Sherwood, T.R.

    1996-01-01

    The problem of matching an ion beam delivered by a high-intensity ion source with an accelerator is considered. The experimental results of highly charged ion beam transport with space-charge compensation by electrons are presented. A tungsten thermionic cathode is used as a source of electrons for beam compensation. An increase of ion beam current density by a factor of 25 is obtained as a result of space-charge compensation at a distance of 3 m from the extraction system. The process of ion beam space-charge compensation, requirements for a source of electrons, and the influence of recombination losses in a space-charge-compensated ion beam are discussed. (author)

  4. High density matter at RHIC

    Indian Academy of Sciences (India)

    are screened, and short range (high momentum) interactions are weak, leading to an ideal gas equation .... I will briefly touch on 'soft physics' ..... thermodynamic concepts to describe multi-particle production has a long history beginning with ...

  5. Silicon-Based Lithium-Ion Capacitor for High Energy and High Power Application

    Science.gov (United States)

    Wu, James J.; Demattia, Brianne; Loyselle, Patricia; Reid, Concha; Kohout, Lisa

    2017-01-01

    Si-based Li-ion capacitor has been developed and demonstrated. The results show it is feasible to improve both power density and energy density in this configuration. The applied current density impacts the power and energy density: low current favors energy density while high current favors power density. Active carbon has a better rate capability than Si. Next StepsFuture Directions. Si electrode needs to be further studied and improved. Further optimization of SiAC ratio and evaluation of its impact on energy density and power density.

  6. Evaporation of carbon using electrons of a high density plasma

    International Nuclear Information System (INIS)

    Muhl, S.; Camps, E.; Escobar A, L.; Garcia E, J.L.; Olea, O.

    1999-01-01

    The high density plasmas are used frequently in the preparation of thin films or surface modification, for example to nitridation. In these processes, are used mainly the ions and the neutrals which compose the plasma. However, the electrons present in the plasma are not used, except in the case of chemical reactions induced by collisions, although the electron bombardment usually get hot the work piece. Through the adequate polarization of a conductor material, it is possible to extract electrons from a high density plasma at low pressure, that could be gotten the evaporation of this material. As result of the interaction between the plasma and the electron flux with the vapor produced, this last will be ionized. In this work, it is reported the use of this novelty arrangement to prepare carbon thin films using a high density argon plasma and a high purity graphite bar as material to evaporate. It has been used substrates outside plasma and immersed in the plasma. Also it has been reported the plasma characteristics (temperature and electron density, energy and ions flux), parameters of the deposit process (deposit rate and ion/neutral rate) as well as the properties of the films obtained (IR absorption spectra and UV/Vis, elemental analysis, hardness and refractive index. (Author)

  7. High current vacuum arc ion source for heavy ion fusion

    International Nuclear Information System (INIS)

    Qi, N.; Schein, J.; Gensler, S.; Prasad, R.R.; Krishnan, M.; Brown, I.

    1999-01-01

    Heavy Ion fusion (HIF) is one of the approaches for the controlled thermonuclear power production. A source of heavy ions with charge states 1+ to 2+, in ∼0.5 A current beams with ∼20 micros pulse widths and ∼10 Hz repetition rates are required. Thermionic sources have been the workhorse for the HIF program to date, but suffer from sloe turn-on, heating problems for large areas, are limited to low (contact) ionization potential elements and offer relatively low ion fluxes with a charge state limited to 1+. Gas injection sources suffer from partial ionization and deleterious neutral gas effects. The above shortcomings of the thermionic ion sources can be overcome by a vacuum arc ion source. The vacuum arc ion source is a good candidate for HIF applications. It is capable of providing ions of various elements and different charge states, in short and long pulse bursts, with low emittance and high beam currents. Under a Phase-I STTR from DOE, the feasibility of the vacuum arc ion source for the HIF applications is investigated. An existing ion source at LBNL was modified to produce ∼0.5 A, ∼60 keV Gd (A∼158) ion beams. The experimental effort concentrated on beam noise reduction, pulse-to-pulse reproducibility and achieving low beam emittance at 0.5 A ion current level. Details of the source development will be reported

  8. Electronic DC transformer with high power density

    NARCIS (Netherlands)

    Pavlovský, M.

    2006-01-01

    This thesis is concerned with the possibilities of increasing the power density of high-power dc-dc converters with galvanic isolation. Three cornerstones for reaching high power densities are identified as: size reduction of passive components, reduction of losses particularly in active components

  9. New aspects of high energy density plasma

    International Nuclear Information System (INIS)

    Hotta, Eiki

    2005-10-01

    The papers presented at the symposium on 'New aspects of high energy density plasma' held at National Institute for Fusion Science are collected in this proceedings. The papers reflect the present status and recent progress in the experiments and theoretical works on high energy density plasma produced by pulsed power technology. The 13 of the presented papers are indexed individually. (J.P.N.)

  10. AMODS and High Energy Density Sciences

    International Nuclear Information System (INIS)

    Rhee, Y.-J.

    2011-01-01

    Following a brief introduction to the Lab for Quantum Optics (LFQO) in KAERI, which has been devoted to the research on atomic spectroscopy for more than 20 years with precision measurement of atomic parameters such as isotope shift, hyperfine structures, autoionization levels and so on as well as with theoretical analysis of atomic systems by developing relativistic calculation methodologies for laser propagation and population dynamics, electron impact ionization, radiative transitions of high Z materials, etc for the application to isotope separation, the AMODS (Atomic Molecular and Optical Database Systems) which was established in 1997 and has been a member of International Data Center Network of IAEA since then is explained by giving an information on the data sources and internal structure of the compilation of AMODS. Since AMODS was explained in detail during last DCN meeting, just a brief introduction is given this time. Then more specific research themes carried out in LFQO in conjunction with A+M data are discussed, including (1) electron impact ionization processes of W, Mo, Be, C, etc, (2) spectra of highly charged ions of W, Xe, and Si, (3) dielectronic recombination process of Fe ion. Also given are the talk about research activities about the simulations of high energy density experiments such as those performed at (1) GEKKO laser facility (Japan) for X-ray photoionization of low temperature Si plasma, which can explain the unsolved arguments on the X-ray spectra of black holes and/or neutron stars, (2) VULCAN laser facility (UK) for two dimensional compression of cylindrical target and investigation of hot electron transport in the compressed target plasma to understand the fast ignition process of laser fusion, (3) LULI laser facility (France) and TITAN laser facility (USA) for one dimensional compression of aluminum targets with different laser energies, and (4) PALS facility (Czech Republic) for 'Laser Induced Cavity Pressure Acceleration' to

  11. High regression rate, high density hybrid fuels, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR program will investigate high energy density novel nanofuels combined with high density binders for use with an N2O oxidizer. Terves has developed...

  12. Magnetization of High Density Hadronic Fluid

    DEFF Research Database (Denmark)

    Bohr, Henrik; Providencia, Constanca; da Providencia, João

    2012-01-01

    In the present paper the magnetization of a high density relativistic fluid of elementary particles is studied. At very high densities, such as may be found in the interior of a neutron star, when the external magnetic field is gradually increased, the energy of the normal phase of the fluid...... in the particle fluid. For nuclear densities above 2 to 3 rho(0), where rho(0) is the equilibrium nuclear density, the resulting magnetic field turns out to be rather huge, of the order of 10(17) Gauss....

  13. Generation of high brightness ion beam from insulated anode PED

    International Nuclear Information System (INIS)

    Matsukawa, Yoshinobu

    1988-01-01

    Generation and focusing of a high density ion beam with high brightness from a organic center part of anode of a PED was reported previously. Mass, charge and energy distribution of this beam were analyzed. Three kind of anode were tried. Many highly ionized medium mass ions (up to C 4+ , O 6+ ) accelarated to several times of voltage difference between anode and cathode were observed. In the case of all insulator anode the current carried by the medium mass ions is about half of that carried by protons. (author)

  14. Possible new form of matter at high density

    International Nuclear Information System (INIS)

    Lee, T.D.

    1974-01-01

    As a preliminary to discussion of the possibility of new forms of matter at high density, questions relating to the vacuum and vacuum excitation are considered. A quasi-classical approach to the development of abnormal nuclear states is undertaken using a Fermi gas of nucleons of uniform density. Discontinuous transitions are considered in the sigma model (tree approximation) followed by brief consideration of higher order loop diagrams. Production and detection of abnormal nuclear states are discussed in the context of high energy heavy ion collisions. Remarks are made on motivation for such research. 8 figures

  15. Highly Stripped Ion Sources for MeV Ion Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, Ady

    2009-06-30

    Original technical objectives of CRADA number PVI C-03-09 between BNL and Poole Ventura, Inc. (PVI) were to develop an intense, high charge state, ion source for MeV ion implanters. Present day high-energy ion implanters utilize low charge state (usually single charge) ion sources in combination with rf accelerators. Usually, a MV LINAC is used for acceleration of a few rnA. It is desirable to have instead an intense, high charge state ion source on a relatively low energy platform (de acceleration) to generate high-energy ion beams for implantation. This de acceleration of ions will be far more efficient (in energy utilization). The resultant implanter will be smaller in size. It will generate higher quality ion beams (with lower emittance) for fabrication of superior semiconductor products. In addition to energy and cost savings, the implanter will operate at a lower level of health risks associated with ion implantation. An additional aim of the project was to producing a product that can lead to long­ term job creation in Russia and/or in the US. R&D was conducted in two Russian Centers (one in Tomsk and Seversk, the other in Moscow) under the guidance ofPVI personnel and the BNL PI. Multiple approaches were pursued, developed, and tested at various locations with the best candidate for commercialization delivered and tested at on an implanter at the PVI client Axcelis. Technical developments were exciting: record output currents of high charge state phosphorus and antimony were achieved; a Calutron-Bemas ion source with a 70% output of boron ion current (compared to 25% in present state-of-the-art). Record steady state output currents of higher charge state phosphorous and antimony and P ions: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb {sup 4 +}, Sb{sup 5+}, and Sb{sup 6+} respectively. Ultimate commercialization goals did not succeed (even though a number of the products like high

  16. Long-time evolution of a low-density ion beam

    International Nuclear Information System (INIS)

    Zachary, A.L.; Cohen, B.I.; Max, C.E.; Arons, J.

    1989-01-01

    With a new, orbit-averaged hybrid computer simulation code, we study a cold, fast low-density ion beam which propagates along the ambient magnetic field as it interacts with a much denser fluid background. We examine the character of the interactions as we vary the ion beam density relative to the background density over the range 1 x 10/sup -5/ to 3 x 10/sup -3/. The low beam density simulations may not be directly observable upstream of the Earth's bow shock, but they are included to help develop an understanding of the results seen in the simulations with high-beam density. However, our highest density simulation falls within the range of solar wind data. All the simulations, regardless of the relative beam density, show three distinct phases: (1) an early or ''linear'' phase; (2) an intermediate or ''trapping'' phase; and (3) a late or ''decorrelation'' phase. In the early phase, the beam excites a nearly monochromatic Alfven wave whose amplitude grows exponentially at a rate given by linear perturbation theory. The wave amplitude saturates when the linear growth rate is of the order of the trapping frequency

  17. Some recent efforts toward high density implosions

    International Nuclear Information System (INIS)

    McClellan, G.E.

    1980-01-01

    Some recent Livermore efforts towards achieving high-density implosions are presented. The implosion dynamics necessary to compress DT fuel to 10 to 100 times liquid density are discussed. Methods of diagnosing the maximum DT density for a specific design are presented along with results to date. The dynamics of the double-shelled target with an exploding outer shell are described, and some preliminary experimental results are presented

  18. Viscosity and attenuation of sound wave in high density deuterium

    International Nuclear Information System (INIS)

    Inoue, Kazuko; Ariyasu, Tomio

    1985-01-01

    The penetration of low frequency sound wave into the fuel deuterium is discussed as for laser fusion. The sound velocity and the attenuation constant due to viscosity are calculated for high density (n = 10 24 -- 10 27 cm -3 , T = 10 -1 -- 10 4 eV) deuterium. The shear viscosity of free electron gas and the bulk viscosity due to ion-ion interaction mainly contribute to the attenuation of sound wave. The sound wave of the frequency below 10 10 Hz can easily penetrate through the compressed fuel deuterium of diameter 1 -- 10 3 μm. (author)

  19. High-intensity sources for light ions

    International Nuclear Information System (INIS)

    Leung, K.N.

    1995-10-01

    The use of the multicusp plasma generator as a source of light ions is described. By employing radio-frequency induction discharge, the performance of the multicusp source is greatly improved, both in lifetime and in high brightness H + and H - beam production. A new technique for generating multiply-charged ions in this type of ion source is also presented

  20. High Energy Density Polymer Film Capacitors

    National Research Council Canada - National Science Library

    Boufelfel, Ali

    2006-01-01

    High-energy-density capacitors that are compact and light-weight are extremely valuable in a number of critical DoD systems that include portable field equipment, pulsed lasers, detection equipment...

  1. Investigation of the alpha cluster model and the density matrix expansion in ion-ion collision

    International Nuclear Information System (INIS)

    Rashdan, M.B.M.

    1986-01-01

    This thesis deals with the investigation of the alpha cluster model (ACM) of brink and studies of the accuracy of the density matrix expansion (DME) approximation in deriving the real part of the ion-ion optical potential. the ACM is applied to calculate the inelastic 0 1 + →2 1 + charge form factor for electron scattering by 12 C to investigate the validity of this model for 12 C nucleus. it is found that the experimental curve can be fitted over the entire range of the momentum transfer by a generator - coordinate state for the 2 1 + state that consist of a superposition of two triangular ACM states with two different cluster separations and the same oscillator parameter

  2. High Resolution Scanning Ion Microscopy

    NARCIS (Netherlands)

    Castaldo, V.

    2011-01-01

    The structure of the thesis is the following. The first chapter is an introduction to scanning microscopy, where the path that led to the Focused Ion Beam (FIB) is described and the main differences between electrons and ion beams are highlighted. Chapter 2 is what is normally referred to (which I

  3. Energy confinement of high-density tokamaks

    NARCIS (Netherlands)

    Schüller, F.C.; Schram, D.C.; Coppi, B.; Sadowski, W.

    1977-01-01

    Neoclassical ion heat conduction is the major energy loss mechanism in the center of an ohmically heated high-d. tokamak discharge (n>3 * 1020 m-3). This fixes the mutual dependence of plasma quantities on the axis and leads to scaling laws for the poloidal b and energy confinement time, given the

  4. Polyatomic ions from a high current ion implanter driven by a liquid metal ion source

    Science.gov (United States)

    Pilz, W.; Laufer, P.; Tajmar, M.; Böttger, R.; Bischoff, L.

    2017-12-01

    High current liquid metal ion sources are well known and found their first application as field emission electric propulsion thrusters in space technology. The aim of this work is the adaption of such kind of sources in broad ion beam technology. Surface patterning based on self-organized nano-structures on, e.g., semiconductor materials formed by heavy mono- or polyatomic ion irradiation from liquid metal (alloy) ion sources (LMAISs) is a very promising technique. LMAISs are nearly the only type of sources delivering polyatomic ions from about half of the periodic table elements. To overcome the lack of only very small treated areas by applying a focused ion beam equipped with such sources, the technology taken from space propulsion systems was transferred into a large single-end ion implanter. The main component is an ion beam injector based on high current LMAISs combined with suited ion optics allocating ion currents in the μA range in a nearly parallel beam of a few mm in diameter. Different types of LMAIS (needle, porous emitter, and capillary) are presented and characterized. The ion beam injector design is specified as well as the implementation of this module into a 200 kV high current ion implanter operating at the HZDR Ion Beam Center. Finally, the obtained results of large area surface modification of Ge using polyatomic Bi2+ ions at room temperature from a GaBi capillary LMAIS will be presented and discussed.

  5. Formation and termination of High ion temperature mode in Heliotron/torsatron plasmas

    International Nuclear Information System (INIS)

    Ida, K.; Kondo, K.; Nagasaki, K.

    1997-01-01

    Physics of the formation and termination of High ion temperature mode (high T i mode) are studied by controlling density profiles and radial electric field. High ion temperature mode is observed for neutral beam heated plasmas in Heliotron/torsatron plasmas (Heliotron-E). This high T i mode plasma is characterized by a peaked ion temperature profile and is associated with a peaked electron density profile produced by neutral beam fueling with low wall recycling. This high T i mode is terminated by flattening the electron density caused by either gas puffing or second harmonic ECH (core density 'pump-out'). (author)

  6. Pulsed high current ion beam processing equipment

    International Nuclear Information System (INIS)

    Korenev, S.A.; Perry, A.

    1995-01-01

    A pulsed high voltage ion source is considered for use in ion beam processing for the surface modification of materials, and deposition of conducting films on different substrates. The source consists of an Arkad'ev-Marx high voltage generator, a vacuum ion diode based on explosive ion emission, and a vacuum chamber as substrate holder. The ion diode allows conducting films to be deposited from metal or allow sources, with ion beam mixing, onto substrates held at a pre-selected temperature. The main variables can be set in the ranges: voltage 100-700 kV, pulse length 0.3 μs, beam current 1-200 A depending on the ion chosen. The applications of this technology are discussed in semiconductor, superconductor and metallizing applications as well as the direction of future development and cost of these devices for commercial application. 14 refs., 6 figs

  7. High-density limit of quantum chromodynamics

    International Nuclear Information System (INIS)

    Alvarez, E.

    1983-01-01

    By means of a formal expansion of the partition function presumably valid at large baryon densities, the propagator of the quarks is expressed in terms of the gluon propagator. This result is interpreted as implying that correlations between quarks and gluons are unimportant at high enough density, so that a kind of mean-field approximation gives a very accurate description of the physical system

  8. High density data recording for SSCL linac

    International Nuclear Information System (INIS)

    VanDeusen, A.L.; Crist, C.

    1993-01-01

    The Superconducting Super Collider Laboratory and AlliedSignal Aerospace have collaboratively developed a high density data monitoring system for beam diagnostic activities. The 128 channel data system is based on a custom multi-channel high speed digitizer card for the VXI bus. The card is referred to as a Modular Input VXI (MIX) digitizer. Multiple MIX cards are used in the complete system to achieve the necessary high channel density requirements. Each MIX digitizer card also contains programmable signal conditioning, and enough local memory to complete an entire beam scan without assistance from the host processor

  9. High accuracy ion optics computing

    International Nuclear Information System (INIS)

    Amos, R.J.; Evans, G.A.; Smith, R.

    1986-01-01

    Computer simulation of focused ion beams for surface analysis of materials by SIMS, or for microfabrication by ion beam lithography plays an important role in the design of low energy ion beam transport and optical systems. Many computer packages currently available, are limited in their applications, being inaccurate or inappropriate for a number of practical purposes. This work describes an efficient and accurate computer programme which has been developed and tested for use on medium sized machines. The programme is written in Algol 68 and models the behaviour of a beam of charged particles through an electrostatic system. A variable grid finite difference method is used with a unique data structure, to calculate the electric potential in an axially symmetric region, for arbitrary shaped boundaries. Emphasis has been placed upon finding an economic method of solving the resulting set of sparse linear equations in the calculation of the electric field and several of these are described. Applications include individual ion lenses, extraction optics for ions in surface analytical instruments and the design of columns for ion beam lithography. Computational results have been compared with analytical calculations and with some data obtained from individual einzel lenses. (author)

  10. Surface ionization ion source with high current

    International Nuclear Information System (INIS)

    Fang Jinqing; Lin Zhizhou; Yu Lihua; Zhan Rongan; Huang Guojun; Wu Jianhua

    1986-04-01

    The working principle and structure of a surface ionization ion source with high current is described systematically. Some technological keypoints of the ion source are given in more detail, mainly including: choosing and shaping of the material of the surface ionizer, heating of the ionizer, distributing of working vapour on the ionizer surface, the flow control, the cooling problem at the non-ionization surface and the ion optics, etc. This ion source has been used since 1972 in the electromagnetic isotope separator with 180 deg angle. It is suitable for separating isotopes of alkali metals and rare earth metals. For instance, in the case of separating Rubidium, the maximum ion current of Rbsup(+) extracted from the ion source is about 120 mA, the maximum ion current accepted by the receiver is about 66 mA, the average ion current is more than 25 mA. The results show that our ion source have advantages of high ion current, good characteristics of focusing ion beam, working stability and structure reliability etc. It may be extended to other fields. Finally, some interesting phenomena in the experiment are disccused briefly. Some problems which should be investigated are further pointed out

  11. Recent advances in high current vacuum arc ion sources for heavy ion fusion

    CERN Document Server

    Qi Nian Sheng; Prasad, R R; Krishnan, M S; Anders, A; Kwan, J; Brown, I

    2001-01-01

    For a heavy ion fusion induction linac driver, a source of heavy ions with charge states 1+-3+, approx 0.5 A current beams, approx 20 mu s pulse widths and approx 10 Hz repetition rates is required. Thermionic sources have been the workhorse for the Heavy Ion Fusion (HIF) program to date, but suffer from heating problems for large areas and contamination. They are limited to low (contact) ionization potential elements and offer relatively low ion fluxes with a charge state limited to 1+. Gas injection sources suffer from partial ionization and deleterious neutral gas effects. The above shortcomings of the thermionic ion sources can be overcome by a vacuum arc ion source. The vacuum arc ion source is a good candidate for HIF applications. It is capable of providing ions of various elements and different charge states in short and long pulse bursts and high beam current density. Under a Phase-I STTR from DOE, the feasibility of the vacuum arc ion source for the HIF applications was investigated. We have modifie...

  12. Development of a high current ion implanter

    International Nuclear Information System (INIS)

    Choi, Byung Ho; Kim, Wan; Jin, Jeong Tae

    1990-01-01

    A high current ion implanter of the energy of 100 Kev and the current of about 100 mA has been developed for using the high dose ion implantation, surface modification of steels and ceramics, and ion beam milling. The characteristics of the beam extraction and transportation are investigated. A duoPIGatron ion source compatible with gas ion extraction of about 100 mA, a single gap acceleration tube which is able to compensate the divergence due to the space charge effect, and a beam transport system with the concept of the space charge neutralization are developed for the high current machine. The performance of the constructed machine shows that nitrogen, argon, helium, hydrogen and oxygen ion beams are successfully extracted and transported at a beam divergence due to space charge effect is negligible in the operation pressure of 2 x 10 -5 torr. (author)

  13. Density functional study of isoguanine tetrad and pentad sandwich complexes with alkali metal ions.

    Science.gov (United States)

    Meyer, Michael; Steinke, Thomas; Sühnel, Jürgen

    2007-02-01

    Isoguanine tetraplexes and pentaplexes contain two or more stacked polyads with intercalating metal ions. We report here the results of a density functional study of sandwiched isoguanine tetrad and pentad complexes consisting of two polyads with Na(+), K(+) and Rb(+) ions at the B3LYP level. In comparison to single polyad metal ion complexes, there is a trend towards increased non-planarity of the polyads in the sandwich complexes. In general, the pentad sandwiches have relatively planar polyad structures, whereas the tetrad complexes contain highly non-planar polyad building blocks. As in other sandwich complexes and in metal ion complexes with single polyads, the metal ion-base interaction energy plays an essential role. In iG sandwich structures, this interaction energy is slightly larger than in the corresponding guanine sandwich complexes. Because the base-base interaction energy is even more increased in passing from guanine to isoguanine, the isoguanine sandwiches are thus far the only examples where the base-base interaction energy is larger than the base-metal ion interaction energy. Stacking interactions have been studied in smaller models consisting of two bases, retaining the geometry from the complete complex structures. From the data obtained at the B3LYP and BH&H levels and with Møller-Plesset perturbation theory, one can conclude that the B3LYP method overestimates the repulsion in stacked base dimers. For the complexes studied in this work, this is only of minor importance because the direct inter-tetrad or inter-pentad interaction is supplemented by a strong metal ion-base interaction. Using a microsolvation model, the metal ion preference K(+) approximately Rb(+) > Na(+) is found for tetrad complexes. On the other hand, for pentads the ordering is Rb(+) > K(+) > Na(+). In the latter case experimental data are available that agree with this prediction.

  14. Laser fusion and high energy density science

    International Nuclear Information System (INIS)

    Kodama, Ryosuke

    2005-01-01

    High-power laser technology is now opening a variety of new fields of science and technology using laser-produced plasmas. The laser plasma is now recognized as one of the important tools for the investigation and application of matter under extreme conditions, which is called high energy density science. This chapter shows a variety of applications of laser-produced plasmas as high energy density science. One of the more attractive industrial and science applications is the generation of intense pulse-radiation sources, such as the generation of electro-magnetic waves in the ranges of EUV (Extreme Ultra Violet) to gamma rays and laser acceleration of charged particles. The laser plasma is used as an energy converter in this regime. The fundamental science applications of high energy density physics are shown by introducing laboratory astrophysics, the equation of state of high pressure matter, including warm dense matter and nuclear science. Other applications are also presented, such as femto-second laser propulsion and light guiding. Finally, a new systematization is proposed to explore the possibility of the high energy density plasma application, which is called high energy plasma photonics''. This is also exploration of the boundary regions between laser technology and beam optics based on plasma physics. (author)

  15. Versatile high current metal ion implantation facility

    International Nuclear Information System (INIS)

    Brown, I.G.; Dickinson, M.R.; Galvin, J.E.; Godechot, X.; MacGill, R.A.

    1992-01-01

    A metal ion implantation facility has been developed with which high current beams of practically all the solid metals of the periodic table can be produced. A multicathode, broad-beam, metal vapor vacuum arc ion source is used to produce repetitively pulsed metal ion beams at an extraction voltage of up to 100 kV, corresponding to an ion energy of up to several hundred kiloelectronvolts because of the ion charge state multiplicity, and with a beam current of up to several amps peak pulsed and several tens of milliamps time averaged delivered onto a downstream target. Implantation is done in a broad-beam mode, with a direct line of sight from ion source to target. Here we summarize some of the features of the ion source and the implantation facility that has been built up around it. (orig)

  16. High Density Digital Data Storage System

    Science.gov (United States)

    Wright, Kenneth D., II; Gray, David L.; Rowland, Wayne D.

    1991-01-01

    The High Density Digital Data Storage System was designed to provide a cost effective means for storing real-time data from the field-deployable digital acoustic measurement system. However, the high density data storage system is a standalone system that could provide a storage solution for many other real time data acquisition applications. The storage system has inputs for up to 20 channels of 16-bit digital data. The high density tape recorders presently being used in the storage system are capable of storing over 5 gigabytes of data at overall transfer rates of 500 kilobytes per second. However, through the use of data compression techniques the system storage capacity and transfer rate can be doubled. Two tape recorders have been incorporated into the storage system to produce a backup tape of data in real-time. An analog output is provided for each data channel as a means of monitoring the data as it is being recorded.

  17. Probing neutral density at the plasma edge of Tore Supra with CX excited impurity ions

    International Nuclear Information System (INIS)

    Hess, W.R.; Mattioli, M.; Guirlet, R.

    1993-01-01

    In Tokamak plasma physics renewed interest in visible spectroscopy has grown for two reasons. The use of fiber optics allows observation of local sources of both impurities and of hydrogen by observing radiation of low ionization states. Moreover, charge exchange spectroscopy (CXS) with either auxiliary or heating neutral beams is a standard technique to determine the ion temperature and impurity density profiles. After a short description of the experimental setup and the ergodic divertor of Tore Supra (TS), two discharges in which space-resolved observations of the CVI (8-7) line clearly show the presence of CX-related effects. A well isolated spectral line at 5304.6 A is discussed. Tentative identification as CIII (1s 2 2s, 7-5) is suggested. The conclusion shows the usefulness of the reported results for probing neutral density at the plasma edge by detecting CX excited impurity ions and that highly ionized C 6+ ions exist in the MARFE regions. To the best of our knowledge, only very low ionization C and O ions (such as CIII or OIV) have been previously reported in these regions

  18. Ion beam enhancement in magnetically insulated ion diodes for high-intensity pulsed ion beam generation in non-relativistic mode

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, X. P. [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Zhang, Z. C.; Lei, M. K., E-mail: surfeng@dlut.edu.cn [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Pushkarev, A. I. [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Laboratory of Beam and Plasma Technology, High Technologies Physics Institute, Tomsk Polytechnic University, 30, Lenin Ave, 634050 Tomsk (Russian Federation)

    2016-01-15

    High-intensity pulsed ion beam (HIPIB) with ion current density above Child-Langmuir limit is achieved by extracting ion beam from anode plasma of ion diodes with suppressing electron flow under magnetic field insulation. It was theoretically estimated that with increasing the magnetic field, a maximal value of ion current density may reach nearly 3 times that of Child-Langmuir limit in a non-relativistic mode and close to 6 times in a highly relativistic mode. In this study, the behavior of ion beam enhancement by magnetic insulation is systematically investigated in three types of magnetically insulated ion diodes (MIDs) with passive anode, taking into account the anode plasma generation process on the anode surface. A maximal enhancement factor higher than 6 over the Child-Langmuir limit can be obtained in the non-relativistic mode with accelerating voltage of 200–300 kV. The MIDs differ in two anode plasma formation mechanisms, i.e., surface flashover of a dielectric coating on the anode and explosive emission of electrons from the anode, as well as in two insulation modes of external-magnetic field and self-magnetic field with either non-closed or closed drift of electrons in the anode-cathode (A-K) gap, respectively. Combined with ion current density measurement, energy density characterization is employed to resolve the spatial distribution of energy density before focusing for exploring the ion beam generation process. Consistent results are obtained on three types of MIDs concerning control of neutralizing electron flows for the space charge of ions where the high ion beam enhancement is determined by effective electron neutralization in the A-K gap, while the HIPIB composition of different ion species downstream from the diode may be considerably affected by the ion beam neutralization during propagation.

  19. Extreme states of matter high energy density physics

    CERN Document Server

    Fortov, Vladimir E

    2016-01-01

    With its many beautiful colour pictures, this book gives fascinating insights into the unusual forms and behaviour of matter under extremely high pressures and temperatures. These extreme states are generated, among other things, by strong shock, detonation and electric explosion waves, dense laser beams,electron and ion beams, hypersonic entry of spacecraft into dense atmospheres of planets, and in many other situations characterized by extremely high pressures and temperatures.Written by one of the world's foremost experts on the topic, this book will inform and fascinate all scientists dealing with materials properties and physics, and also serve as an excellent introduction to plasma-, shock-wave and high-energy-density physics for students and newcomers seeking an overview. This second edition is thoroughly revised and expanded, in particular with new material on high energy-density physics, nuclear explosions and other nuclear transformation processes.

  20. Measuring the radial density distribution of light emission around the track of fast ions in nitrogen

    International Nuclear Information System (INIS)

    Ibach, T.

    1983-01-01

    For analysing the emission and stopping of ionization electrons (σ-electrons) emitted by fast ions passing through a gas, the radial density distribution of the light emission of the (0,0) transition of two optical bands in nitrogen have been measured. The systems selected for the epxeriments are the 2nd positive system (2.PS) at 337.1 nm primarily excited by low-energy electrons of about 20 eV, and the first negative system (1.NS) at 391.4 nm excited by faster electrons and simultaneous ionization. The equipment developed for the experiments records the light emission with a telescope-type optical arrangement including interference filters, allowing high local resolution and dynamics of the measured range. The measurements have been carried out at pressures between 0.133 and 13.3 mbar, using photons of energies ranging from 270 keV to 2.8 MeV, helium 3 beams of 270 keV/u and 500 keV/u, and neon beams of 270 keV/u. Abel's inversion applied to the distance functions allows calculation of the spatial light emission density which is normalized for a gas density of 1 g/cm 3 . The profiles of the two bands indicate that the σ-electron spectrum gets harder in outward direction. Next to the beam the impact density decreases faster with increasing ion energy than the stopping power (increasing interaction range of the σ-electrons). With photon beams, about half of the whole light emission in the 1. NS, and of the ionization, is induced by primary interactions of the ion beam. This proportion decreases at constant energy per nucleon with increasing atomic number of the ions as compared with the σ-electrons. The primary σ-emission gets harder with higher atomic numbers. (orig./HP) [de

  1. High brightness K+ ion source for heavy ion fusion linear induction accelerators

    International Nuclear Information System (INIS)

    Henestroza, E.; Eylon, S.; Chupp, W.; Rutkowski, H.

    1992-01-01

    Low emittance, high current, singly charged potassium thermionic ion sources are being developed for the Induction Linac System Experiment injector, ILSE. The ILSE, now in study at LBL, will address the physics issues of particle beams in a heavy ion fusion driver scenario. The K + ion beam considered is emitted thermionically into a diode gap from alumino-silicate layers (zeolite) coated on a porous tungsten cup. The Single Beam Transport Experiment (SBTE) 120keV cesium source was redesigned and modified with the aid of an ion optics and gun design program (EGUN) to enable the evaluation of the K + source performance at high extraction currents of about 80mA from a one inch diameter source. The authors report on the source fabrication technique and performance, including total current and current density profile measurements using Faraday cups, phase space distributions using the double slit scanning technique, and source emitting surface temperature dependence on heating power using a wire pyrometer

  2. Low energy ion implantation and high energy heavy ion irradiation in C60 films

    International Nuclear Information System (INIS)

    Narayanan, K.L.; Yamaguchi, M.; Dharmarasu, N.; Kojima, N.; Kanjilal, D.

    2001-01-01

    C 60 films have been bombarded with low energy boron ions and high energy swift heavy ions (SHI) of silver and oxygen at different doses. Raman scattering and Fourier transform infrared (FTIR) studies were carried out on the virgin and irradiated films and the results are in good agreement with each other. The films subject to low energy boron ion implantation showed destruction of the bukky balls whereas the films subject to high energy ion irradiation did not show appreciable effects on their structure. These results indicate that C 60 films are more prone to defects by elastic collision and subsequent implantation at lower energy. Irradiation at higher energy was less effective in creating appreciable defects through electronic excitation by inelastic collisions at similar energy density

  3. High density regimes and beta limits in JET

    International Nuclear Information System (INIS)

    Smeulders, P.

    1990-01-01

    Results are first presented on the density limit in JET discharges with graphite (C), Be gettered graphite and Be limiters. There is a clear improvement in the case of Be limiters. The Be gettered phase showed no increase in the gas fueled density limit, except with Ion Cyclotron Resonance Heating (ICRH), but, the limit changed character. During MARFE-formation, any further increase in density was prevented, leading to a soft density limit. The soft density limit was a function of input power and impurity content with a week dependence on q. Helium and pellet fuelled discharges exceeded the gas-fuelled global density limits, but essentially had the same edge limit. In the second part, results are presented of high β operation in low-B Double-Null (DN) X-point configurations with Be-gettered carbon target plates. The Troyon limit was reached during H-mode discharges and toroidal β values of 5.5% were obtained. At high beta, the sawteeth were modified and characterised by very rapid heat-waves and fishbone-like pre- and post-cursors with strongly ballooning character. 17 refs., 5 figs

  4. Development of a CMOS process using high energy ion implantation

    International Nuclear Information System (INIS)

    Stolmeijer, A.

    1986-01-01

    The main interest of this thesis is the use of complementary metal oxide semiconductors (CMOS) in electronic technology. Problems in developing a CMOS process are mostly related to the isolation well of p-n junctions. It is shown that by using high energy ion implantation, it is possible to reduce lateral dimensions to obtain a rather high packing density. High energy ion implantation is also presented as a means of simplifying CMOS processing, since extended processing steps at elevated temperatures are superfluous. Process development is also simplified. (Auth.)

  5. High-energy ion implantation of materials

    International Nuclear Information System (INIS)

    Williams, J.M.

    1991-11-01

    High-energy ion implantation is an extremely flexible type of surface treatment technique, in that it offers the possibility of treating almost any type of target material or product with ions of almost any chemical species, or combinations of chemical species. In addition, ion implantations can be combined with variations in temperature during or after ion implantation. As a result, the possibility of approaching a wide variety of surface-related materials science problems exists with ion implantation. This paper will outline factors pertinent to application of high-energy ion implantation to surface engineering problems. This factors include fundamental advantages and limitations, economic considerations, present and future equipment, and aspects of materials science

  6. High throughput nonparametric probability density estimation.

    Science.gov (United States)

    Farmer, Jenny; Jacobs, Donald

    2018-01-01

    In high throughput applications, such as those found in bioinformatics and finance, it is important to determine accurate probability distribution functions despite only minimal information about data characteristics, and without using human subjectivity. Such an automated process for univariate data is implemented to achieve this goal by merging the maximum entropy method with single order statistics and maximum likelihood. The only required properties of the random variables are that they are continuous and that they are, or can be approximated as, independent and identically distributed. A quasi-log-likelihood function based on single order statistics for sampled uniform random data is used to empirically construct a sample size invariant universal scoring function. Then a probability density estimate is determined by iteratively improving trial cumulative distribution functions, where better estimates are quantified by the scoring function that identifies atypical fluctuations. This criterion resists under and over fitting data as an alternative to employing the Bayesian or Akaike information criterion. Multiple estimates for the probability density reflect uncertainties due to statistical fluctuations in random samples. Scaled quantile residual plots are also introduced as an effective diagnostic to visualize the quality of the estimated probability densities. Benchmark tests show that estimates for the probability density function (PDF) converge to the true PDF as sample size increases on particularly difficult test probability densities that include cases with discontinuities, multi-resolution scales, heavy tails, and singularities. These results indicate the method has general applicability for high throughput statistical inference.

  7. High density implosion experiments at Nova

    International Nuclear Information System (INIS)

    Cable, M.D.; Hatchett, S.P.; Nelson, M.B.; Lerche, R.A.; Murphy, T.J.; Ress, D.B.

    1994-01-01

    Deuterium filled glass microballoons are used as indirectly driven targets for implosion experiments at the Nova Laser Fusion Facility. High levels of laser precision were required to achieve fuel densities and convergences to an ignition scale hot spot. (AIP) copyright 1994 American Institute of Physics

  8. High Density GEOSAT/GM Altimeter Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The high density Geosat/GM altimeter data south of 30 S have finally arrived. In addition, ERS-1 has completed more than 6 cycles of its 35-day repeat track. These...

  9. High density aseismic spent fuel storage racks

    International Nuclear Information System (INIS)

    Louvat, J.P.

    1985-05-01

    After the reasons of the development of high density aseismic spent fuel racks by FRAMATOME and LEMER, a description is presented, as also the codes, standards and regulations used to design this FRAMATOME storage rack. Tests have been carried out concerning criticality, irradiation of Cadminox, corrosion of the cell, and the seismic behaviour

  10. Highly reversible open framework nanoscale electrodes for divalent ion batteries.

    Science.gov (United States)

    Wang, Richard Y; Wessells, Colin D; Huggins, Robert A; Cui, Yi

    2013-01-01

    The reversible insertion of monovalent ions such as lithium into electrode materials has enabled the development of rechargeable batteries with high energy density. Reversible insertion of divalent ions such as magnesium would allow the creation of new battery chemistries that are potentially safer and cheaper than lithium-based batteries. Here we report that nanomaterials in the Prussian Blue family of open framework materials, such as nickel hexacyanoferrate, allow for the reversible insertion of aqueous alkaline earth divalent ions, including Mg(2+), Ca(2+), Sr(2+), and Ba(2+). We show unprecedented long cycle life and high rate performance for divalent ion insertion. Our results represent a step forward and pave the way for future development in divalent batteries.

  11. Aerosol nucleation in an ultra-low ion density environment

    DEFF Research Database (Denmark)

    Pedersen, Jens Olaf Pepke; Enghoff, Martin Andreas Bødker; Paling, Sean M.

    2012-01-01

    Ion-induced nucleation has been studied in a deep underground ultra-low background radiation environment where the role of ions can be distinguished from alternative neutral aerosol nucleation mechanisms. Our results demonstrate that ions have a significant effect on the production of small...... sulfuric acid–water clusters over a range of sulfuric acid concentrations although neutral nucleation mechanisms remain evident at low ionization levels. The effect of ions is found both to enhance the nucleation rate of stable clusters and the initial growth rate. The effects of possible contaminations...

  12. Evaluation of the ion-density measurements by the Indian satellite SROSS-C2

    Science.gov (United States)

    Subrahmanyam, P.; Jain, A. R.; Maini, H. K.; Bahl, M.; Das, Rupesh M.; Garg, S. C.; Niranjan, K.

    2010-12-01

    The ion and electron F region plasma measurements made by the ion and electron Retarding Potential Analyzers (RPAs) onboard the Indian satellite SROSS-C2, have yielded excellent data set over the Indian region for more than half a solar cycle, after the SROSS-C2 launch in May 1994. The absolute ion density, ion temperature, and ion composition parameters are derived from these in situ measurements and used by many workers. In this paper the absolute values of ion density derived from the ion RPA measurements are compared and evaluated with the measurements made by ground-based ionosondes located in the Indian region and close to the SROSS-C2 orbital path. It is shown that a slight adjustment in efficiency factor of the ion RPA sensor brings the in situ measurements much closer to those obtained from the ground-based ionosonde measurements taking into account the model calculations. It may be mentioned that this is a correction to the ion density measurement by SROSS-C2 by a fixed proportion (14-11.4%). The effect of change in efficiency factor on the ion current, which is used to deduce the ion number density, is demonstrated and discussed.

  13. Effects of the instability enhanced friction on relative ion densities in a two-ion species low-temperature plasma

    Science.gov (United States)

    Vukovic, Mirko

    2011-10-01

    The instability enhanced friction theory of Baalrud & Hegna (Phys. Plasmas 18, 023505 (2011)) predicts that for comparable ion densities the ions nearly reach a common velocity near the sheath edge in a low temperature plasma. The theory was experimentally confirmed by Yip, Hershkowitz, & Severn (Phys. Rev. Letters 104, 225003 (2010)). We will explore the effects of the theory on relative ion densities in a numerical simulation of an Ar/Xe plasma. Results for a 0D plasma model (Lieberman, Lichtenberg, Principles of Plasma Discharges and Materials Processing, 2005) will be presented.

  14. Low-density silicon thin films for lithium-ion battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Demirkan, M.T., E-mail: tmdemirkan@ualr.edu [Department of Physics and Astronomy, University of Arkansas at Little Rock, Little Rock, AR 72204 (United States); Department of Materials Science and Engineering, Gebze Technical University, Kocaeli (Turkey); Trahey, L. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Karabacak, T. [Department of Physics and Astronomy, University of Arkansas at Little Rock, Little Rock, AR 72204 (United States)

    2016-02-01

    Density of sputter deposited silicon (Si) thin films was changed by a simple working gas pressure control process, and its effects on the cycling performance of Si films in Li-ion batteries as anodes was investigated. Higher gas pressure results in reduced film densities due to a shadowing effect originating from lower mean free path of sputter atoms, which leads to a wider angular distribution of the incoming flux and formation of a porous film microstructure. Si thin film anodes of different densities ranging from 2.27 g/cm{sup 3} (film porosity ~ 3%) down to 1.64 g/cm{sup 3} (~ 30% porosity) were fabricated by magnetron sputtering at argon pressures varying from 0.2 Pa to 2.6 Pa, respectively. High density Si thin film anodes of 2.27 g/cm{sup 3} suffered from an unstable cycling behavior during charging/discharging depicted by a continuous reduction in specific down to ~ 830 mAh/g at the 100th cycle. Electrochemical properties of lower density films with 1.99 g/cm{sup 3} (~ 15% porosity) and 1.77 g/cm{sup 3} (~ 24% porosity) got worse resulting in only ~ 100 mAh/g capacity at 100th cycle. On the other hand, as the density of anode was further reduced down to about 1.64 g/cm{sup 3} (~ 30% porosity), cycling stability and capacity retention significantly improved resulting in specific capacity values ~ 650 mAh/g at 100th cycle with coulombic efficiencies of > 98%. Enhancement in our low density Si film anodes are believed to mainly originate from the availability of voids for volumetric expansion during lithiation and resulting compliant behavior that provides superior mechanical and electrochemical stability. - Highlights: • Low density Si thin films were studied as Li-ion battery anodes. • Low density Si films were fabricated by magnetron sputter deposition. • Density of Si films reduced down to as low as ~ 1.64 g/cm{sup 3} with a porosity of ~ 30% • Low density Si films presented superior mechanical properties during cycling.

  15. New development of laser ion source for highly charged ion beam production at Institute of Modern Physics (invited).

    Science.gov (United States)

    Zhao, H Y; Zhang, J J; Jin, Q Y; Liu, W; Wang, G C; Sun, L T; Zhang, X Z; Zhao, H W

    2016-02-01

    A laser ion source based on Nd:YAG laser has been being studied at the Institute of Modern Physics for the production of high intensity high charge state heavy ion beams in the past ten years, for possible applications both in a future accelerator complex and in heavy ion cancer therapy facilities. Based on the previous results for the production of multiple-charged ions from a wide range of heavy elements with a 3 J/8 ns Nd:YAG laser [Zhao et al., Rev. Sci. Instrum. 85, 02B910 (2014)], higher laser energy and intensity in the focal spot are necessary for the production of highly charged ions from the elements heavier than aluminum. Therefore, the laser ion source was upgraded with a new Nd:YAG laser, the maximum energy of which is 8 J and the pulse duration can be adjusted from 8 to 18 ns. Since then, the charge state distributions of ions from various elements generated by the 8 J Nd:YAG laser were investigated for different experimental conditions, such as laser energy, pulse duration, power density in the focal spot, and incidence angle. It was shown that the incidence angle is one of the most important parameters for the production of highly charged ions. The capability of producing highly charged ions from the elements lighter than silver was demonstrated with the incidence angle of 10° and laser power density of 8 × 10(13) W cm(-2) in the focal spot, which makes a laser ion source complementary to the superconducting electron cyclotron resonance ion source for the future accelerator complex especially in terms of the ion beam production from some refractory elements. Nevertheless, great efforts with regard to the extraction of intense ion beams, modification of the ion beam pulse duration, and reliability of the ion source still need to be made for practical applications.

  16. Models for Experimental High Density Housing

    Science.gov (United States)

    Bradecki, Tomasz; Swoboda, Julia; Nowak, Katarzyna; Dziechciarz, Klaudia

    2017-10-01

    The article presents the effects of research on models of high density housing. The authors present urban projects for experimental high density housing estates. The design was based on research performed on 38 examples of similar housing in Poland that have been built after 2003. Some of the case studies show extreme density and that inspired the researchers to test individual virtual solutions that would answer the question: How far can we push the limits? The experimental housing projects show strengths and weaknesses of design driven only by such indexes as FAR (floor attenuation ratio - housing density) and DPH (dwellings per hectare). Although such projects are implemented, the authors believe that there are reasons for limits since high index values may be in contradiction to the optimum character of housing environment. Virtual models on virtual plots presented by the authors were oriented toward maximising the DPH index and DAI (dwellings area index) which is very often the main driver for developers. The authors also raise the question of sustainability of such solutions. The research was carried out in the URBAN model research group (Gliwice, Poland) that consists of academic researchers and architecture students. The models reflect architectural and urban regulations that are valid in Poland. Conclusions might be helpful for urban planners, urban designers, developers, architects and architecture students.

  17. Investigation of the silicon ion density during molecular beam epitaxy growth

    Science.gov (United States)

    Eifler, G.; Kasper, E.; Ashurov, Kh.; Morozov, S.

    2002-05-01

    Ions impinging on a surface during molecular beam epitaxy influence the growth and the properties of the growing layer, for example, suppression of dopant segregation and the generation of crystal defects. The silicon electron gun in the molecular beam epitaxy (MBE) equipment is used as a source for silicon ions. To use the effect of ion bombardment the mechanism of generation and distribution of ions was investigated. A monitoring system was developed and attached at the substrate position in the MBE growth chamber to measure the ion and electron densities towards the substrate. A negative voltage was applied to the substrate to modify the ion energy and density. Furthermore the current caused by charge carriers impinging on the substrate was measured and compared with the results of the monitoring system. The electron and ion densities were measured by varying the emission current of the e-gun achieving silicon growth rates between 0.07 and 0.45 nm/s and by changing the voltage applied to the substrate between 0 to -1000 V. The dependencies of ion and electron densities were shown and discussed within the framework of a simple model. The charged carrier densities measured with the monitoring system enable to separate the ion part of the substrate current and show its correlation to the generation rate. Comparing the ion density on the whole substrate and in the center gives a hint to the ion beam focusing effect. The maximum ion and electron current densities obtained were 0.40 and 0.61 μA/cm2, respectively.

  18. Effects of positron density and temperature on large amplitude ion-acoustic waves in an electron-positron-ion plasma

    International Nuclear Information System (INIS)

    Nejoh, Y.N.

    1997-01-01

    The nonlinear wave structures of large amplitude ion-acoustic waves are studied in a plasma with positrons. We have presented the region of existence of the ion-acoustic waves by analysing the structure of the pseudopotential. The region of existence sensitively depends on the positron to electron density ratio, the ion to electron mass ratio and the positron to electron temperature ratio. It is shown that the maximum Mach number increases as the positron temperature increases and the region of existence of the ion-acoustic waves spreads as the positron temperature increases. 12 refs., 6 figs

  19. Lithium-Based High Energy Density Flow Batteries

    Science.gov (United States)

    Bugga, Ratnakumar V. (Inventor); West, William C. (Inventor); Kindler, Andrew (Inventor); Smart, Marshall C. (Inventor)

    2014-01-01

    Systems and methods in accordance with embodiments of the invention implement a lithium-based high energy density flow battery. In one embodiment, a lithium-based high energy density flow battery includes a first anodic conductive solution that includes a lithium polyaromatic hydrocarbon complex dissolved in a solvent, a second cathodic conductive solution that includes a cathodic complex dissolved in a solvent, a solid lithium ion conductor disposed so as to separate the first solution from the second solution, such that the first conductive solution, the second conductive solution, and the solid lithium ionic conductor define a circuit, where when the circuit is closed, lithium from the lithium polyaromatic hydrocarbon complex in the first conductive solution dissociates from the lithium polyaromatic hydrocarbon complex, migrates through the solid lithium ionic conductor, and associates with the cathodic complex of the second conductive solution, and a current is generated.

  20. Preparation and characterization of high-Tc superconducting thin films with high critical current densities

    International Nuclear Information System (INIS)

    Vase, P.

    1991-08-01

    The project was carried out in relation to possible cable and electronics applications of high-T c materials. Laser ablation was used as the deposition technique because of its stoichiometry conservation. Films were made in the YBa 2 Cu 3 O 7 compound due to its relatively simple stoichiometry compared to other High-T c compounds. Much attention was paid to the critical current density. A very high critical current density was reached. By using texture analysis by X-ray diffraction, it was found that films with high critical current densities were epitaxial, while films with low critical current densities contained several crystalline orientations. Four techniques for patterning the films were used - photo lithography and wet etch, laser ablation lithography, laser writing and electron beam lithography and ion milling. Sub-micron patterning has been demonstrated without degradation of the superconducting properties. The achieved patterning resolution is sufficient for preparation of many superconducting components. (AB)

  1. A high current high frequency ions gun

    International Nuclear Information System (INIS)

    Coutant, J.; Prevot, F.; Vienet, R.

    1959-01-01

    A 10 mA protons gun has been developed for different purposes. The first part of the report studies the plasma production with a RF electromagnetic field. Then the ion extraction process is analysed with particular reference to space charge phenomena. The last part describes a three electrode electrostatic lens which focusses the beam. (author) [fr

  2. Development of high current low energy H+ ion source

    International Nuclear Information System (INIS)

    Forrester, A.T.; Crow, J.T.; Goebel, D.M.

    1978-01-01

    The ultimate goal of this work is the development of an ion source suitable for double charge exchange of D + ions to D - ions in cesium or other vapor. Since the fraction of the D + which changes to D - may be as high as 0.35 in the energy below one keV, the process appears very favorable. What is desired is a source of several hundred cm 2 area, with a D + current density greater than, say 0.2A/cm 2 . Small angular spread is essential with up to about 0.1 radian being acceptable. A simple approach to this problem appears to be through fine mesh extraction electrodes. In this system a single grid facing the ion source plasma constitutes the entire extraction electrode system. If the potential difference between the grid and the source plasma is large compared to the ion energy at the plasma boundary, then the distance s 0 is just the Child-Langmuir distance corresponding to the ion current density J and the potential difference V 0 between the plasma and the grid

  3. Highly charged ion trapping and cooling

    International Nuclear Information System (INIS)

    Beck, B. R.; Church, D. A.; Gruber, L.; Holder, J. P.; Schneider, D.; Steiger, J.

    1998-01-01

    In the past few years a cryogenic Penning trap (RETRAP) has been operational at the Electron Beam Ion Trap (EBIT) facility at Lawrence Livermore National Laboratory. The combination of RETRAP and EBIT provides a unique possibility of producing and re-trapping highly charged ions and cooling them to very low temperatures. Due to the high Coulomb potentials in such an ensemble of cold highly charged ions the Coulomb coupling parameter (the ratio of Coulomb potential to the thermal energy) can easily reach values of 172 and more. To study such systems is not only of interest in astrophysics to simulate White Dwarf star interiors but opens up new possibilities in a variety of areas (e.g. laser spectroscopy), cold highly charged ion beams

  4. Measurements of beam current density and proton fraction of a permanent-magnet microwave ion source

    Energy Technology Data Exchange (ETDEWEB)

    Waldmann, Ole; Ludewigt, Bernhard [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

    2011-11-15

    A permanent-magnet microwave ion source has been built for use in a high-yield, compact neutron generator. The source has been designed to produce up to 100 mA of deuterium and tritium ions. The electron-cyclotron resonance condition is met at a microwave frequency of 2.45 GHz and a magnetic field strength of 87.5 mT. The source operates at a low hydrogen gas pressure of about 0.15 Pa. Hydrogen beams with a current density of 40 mA/cm{sup 2} have been extracted at a microwave power of 450 W. The dependence of the extracted proton beam fraction on wall materials and operating parameters was measured and found to vary from 45% for steel to 95% for boron nitride as a wall liner material.

  5. Measurements of beam current density and proton fraction of a permanent-magnet microwave ion source.

    Science.gov (United States)

    Waldmann, Ole; Ludewigt, Bernhard

    2011-11-01

    A permanent-magnet microwave ion source has been built for use in a high-yield, compact neutron generator. The source has been designed to produce up to 100 mA of deuterium and tritium ions. The electron-cyclotron resonance condition is met at a microwave frequency of 2.45 GHz and a magnetic field strength of 87.5 mT. The source operates at a low hydrogen gas pressure of about 0.15 Pa. Hydrogen beams with a current density of 40 mA/cm(2) have been extracted at a microwave power of 450 W. The dependence of the extracted proton beam fraction on wall materials and operating parameters was measured and found to vary from 45% for steel to 95% for boron nitride as a wall liner material. © 2011 American Institute of Physics

  6. Precision laser spectroscopy of highly charged ions

    International Nuclear Information System (INIS)

    Kuehl, T.; Borneis, S.; Becker, S.; Dax, A.; Engel, T.; Grieser, R.; Huber, G.; Klaft, I.; Klepper, O.; Kohl, A.; Marx, D.; Meier, K.; Neumann, R.; Schmitt, F.; Seelig, P.; Voelker, L.

    1996-01-01

    Recently, intense beams of highly charged ions have become available at heavy ion cooler rings. The obstacle for producing these highly interesting candidates is the large binding energy of K-shell electrons in heavy systems in excess of 100 keV. One way to remove these electrons is to strip them off by passing the ion through material. In the cooler ring, the ions are cooled to a well defined velocity. At the SIS/ESR complex it is possible to produce, store, and cool highly charged ions up to bare uranium with intensities exceeding 10 8 atoms in the ring. This opens the door for precision laser spectroscopy of hydrogenlike-heavy ions, e.g. 209 Bi 82+ , and allows to examine the interaction of the single electron with the large fields of the heavy nucleus, exceeding any artificially produced electric and magnetic fields by orders of magnitude. In the electron cooler the interaction of electrons and highly charged ions otherwise only present in the hottest plasmas can be studied. (orig.)

  7. Framatome offers new high density Cadminox racks

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    Framatome have developed a new material called Cadminox for use in high density spent fuel storage racks. It is claimed that Cadminox will remain stable stable in pond storage when racks submerged in boronated water are irradiated by the spent fuel they contain. A brief description of the storage module is given, including the aseismic bearing device which minimises loads on pond walls, racks and fuel assemblies. (UK)

  8. Spin polarization in high density quark matter

    DEFF Research Database (Denmark)

    Bohr, Henrik; Panda, Prafulla K.; Providênci, Constanca

    2013-01-01

    We investigate the occurrence of a ferromagnetic phase transition in high density hadronic matter (e.g., in the interior of a neutron star). This could be induced by a four-fermion interaction analogous to the one which is responsible for chiral symmetry breaking in the Nambu-Jona-Lasinio model, ...... the so-called 2 flavor super-conducting phase to the ferromagnetic phase arises. The color-flavor-locked phase may be completely hidden by the FP....

  9. The car parking problem at high densities

    Science.gov (United States)

    Burgos, E.; Bonadeo, H.

    1989-04-01

    The radial distribution functions of random 1-D systems of sequential hard rods have been studied in the range of very high densities. It is found that as the number of samples rejected before completion increases, anomalies in the pairwise distribution functions arise. These are discussed using analytical solutions for systems of three rods and numerical simulations with twelve rods. The probabilities of different spatial orderings with respect to the sequential order are examined.

  10. Inferring Magnetospheric Heavy Ion Density using EMIC Waves

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun-Hwa; Johnson, Jay R.; Kim, Hyomin; Lee, Dong-Hun

    2014-05-01

    We present a method to infer heavy ion concentration ratios from EMIC wave observations that result from ionion hybrid (IIH) resonance. A key feature of the ion-ion hybrid resonance is the concentration of wave energy in a field-aligned resonant mode that exhibits linear polarization. This mode converted wave is localized at the location where the frequency of a compressional wave driver matches the IIH resonance condition, which depends sensitively on the heavy ion concentration. This dependence makes it possible to estimate the heavy ion concentration ratio. In this letter, we evaluate the absorption coefficients at the IIH resonance at Earth's geosynchronous orbit for variable concentrations of He+ and field-aligned wave numbers using a dipole magnetic field. Although wave absorption occurs for a wide range of heavy ion concentrations, it only occurs for a limited range of field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. Using the wave absorption and observed EMIC waves from GOES-12 satellite, we demonstrate how this technique can be used to estimate that the He+ concentration is around 4% near L = 6.6.

  11. 2D electron density profile measurement in tokamak by laser-accelerated ion-beam probe.

    Science.gov (United States)

    Chen, Y H; Yang, X Y; Lin, C; Wang, L; Xu, M; Wang, X G; Xiao, C J

    2014-11-01

    A new concept of Heavy Ion Beam Probe (HIBP) diagnostic has been proposed, of which the key is to replace the electrostatic accelerator of traditional HIBP by a laser-driven ion accelerator. Due to the large energy spread of ions, the laser-accelerated HIBP can measure the two-dimensional (2D) electron density profile of tokamak plasma. In a preliminary simulation, a 2D density profile was reconstructed with a spatial resolution of about 2 cm, and with the error below 15% in the core region. Diagnostics of 2D density fluctuation is also discussed.

  12. Ignition and burn in contaminated DT fuel at high densities

    International Nuclear Information System (INIS)

    Pasley, J.

    2010-01-01

    Complete text of publication follows. Radiation hydrodynamics simulations have been performed to quantify the effect of contamination upon the ignition threshold in DT at high densities. A detailed thermonuclear burn model, with multi-group multispecies ions, is incorporated alongside a multigroup diffusion approximation for thermal radiation transport. The code used is the research version of the HYADES 1D code. Acceptable levels of contamination are identified for a range of contaminant ion species. A range of different contaminant spatial distribution within the fuel are explored: i) in which the contamination is uniformly distributed throughout the fuel; ii) in which the impurity ions are confined to the hotspot, or iii) where contamination is restricted to a particular region of the hotspot (either centrally, near the surface, or at an intermediate location). Initially the fuel has a constant density with the hotspot located centrally. The overall radius of the fuel is chosen to be sufficiently large that it has no significant effect upon the success or failure of ignition. The evolution of the system is then simulated until ignition either establishes widespread thermonuclear burning, or a failure to ignite is observed. The critical ρr for ignition is found by iteration on the hotspot radius. We show that varying the spatial distribution of the contaminant within the ignition spot has little effect, so long as the total mass of contaminant is held the same. As expected, high-Z contamination is far more detrimental than that by low-Z ions. Discussion of the findings in the context of re-entrant cone-guided fast ignition is presented, in addition to a theoretical interpretation of the results.

  13. High-frequency emissions during the propagation of an electron beam in a high-density plasma

    International Nuclear Information System (INIS)

    Lalita and Tripathi, V.K.

    1988-01-01

    A relativistic annular electron beam passing through a high-density plasma excites Langmuir waves via Cerenkov interaction. The Langmuir waves are backscattered off ions via nonlinear ion Landau damping. At moderately high amplitudes these waves are parametrically up-converted by the beam into high-frequency electromagnetic radiation, as observed in some recent experiments. A nonlocal theory of this process is developed in a cylindrical geometry. It is seen that the growth rate of the Langmuir wave scales as one-third power of beam density. The growth rate of parametric instability scales as one-fourth power of beam density and the square root of beam thickness

  14. High-capacity nanocarbon anodes for lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhang, Haitao; Sun, Xianzhong; Zhang, Xiong; Lin, He; Wang, Kai; Ma, Yanwei

    2015-01-01

    Highlights: • The nanocarbon anodes in lithium-ion batteries deliver a high capacity of ∼1100 mA h g −1 . • The nanocarbon anodes exhibit excellent cyclic stability. • A novel structure of carbon materials, hollow carbon nanoboxes, has potential application in lithium-ion batteries. - Abstract: High energy and power density of secondary cells like lithium-ion batteries become much more important in today’s society. However, lithium-ion battery anodes based on graphite material have theoretical capacity of 372 mA h g −1 and low charging-discharging rate. Here, we report that nanocarbons including mesoporous graphene (MPG), carbon tubular nanostructures (CTN), and hollow carbon nanoboxes (HCB) are good candidate for lithium-ion battery anodes. The nanocarbon anodes have high capacity of ∼1100, ∼600, and ∼500 mA h g −1 at 0.1 A g −1 for MPG, CTN, and HCB, respectively. The capacity of 181, 141, and 139 mA h g −1 at 4 A g −1 for MPG, CTN, and HCB anodes is retained. Besides, nanocarbon anodes show high cycling stability during 1000 cycles, indicating formation of a passivating layer—solid electrolyte interphase, which support long-term cycling. Nanocarbons, constructed with graphene layers which fulfill lithiation/delithiation process, high ratio of graphite edge structure, and high surface area which facilitates capacitive behavior, deliver high capacity and improved rate-capability

  15. Pulsed high-density plasmas for advanced dry etching processes

    International Nuclear Information System (INIS)

    Banna, Samer; Agarwal, Ankur; Cunge, Gilles; Darnon, Maxime; Pargon, Erwine; Joubert, Olivier

    2012-01-01

    Plasma etching processes at the 22 nm technology node and below will have to satisfy multiple stringent scaling requirements of microelectronics fabrication. To satisfy these requirements simultaneously, significant improvements in controlling key plasma parameters are essential. Pulsed plasmas exhibit considerable potential to meet the majority of the scaling challenges, while leveraging the broad expertise developed over the years in conventional continuous wave plasma processing. Comprehending the underlying physics and etching mechanisms in pulsed plasma operation is, however, a complex undertaking; hence the full potential of this strategy has not yet been realized. In this review paper, we first address the general potential of pulsed plasmas for plasma etching processes followed by the dynamics of pulsed plasmas in conventional high-density plasma reactors. The authors reviewed more than 30 years of academic research on pulsed plasmas for microelectronics processing, primarily for silicon and conductor etch applications, highlighting the potential benefits to date and challenges in extending the technology for mass-production. Schemes such as source pulsing, bias pulsing, synchronous pulsing, and others in conventional high-density plasma reactors used in the semiconductor industry have demonstrated greater flexibility in controlling critical plasma parameters such as ion and radical densities, ion energies, and electron temperature. Specifically, plasma pulsing allows for independent control of ion flux and neutral radicals flux to the wafer, which is key to eliminating several feature profile distortions at the nanometer scale. However, such flexibility might also introduce some difficulty in developing new etching processes based on pulsed plasmas. Therefore, the main characteristics of continuous wave plasmas and different pulsing schemes are compared to provide guidelines for implementing different schemes in advanced plasma etching processes based on

  16. Beta decay of highly charged ions

    International Nuclear Information System (INIS)

    Litvinov, Yuri A; Bosch, Fritz

    2011-01-01

    Beta decay of highly charged ions has attracted much attention in recent years. An obvious motivation for this research is that stellar nucleosynthesis proceeds at high temperatures where the involved atoms are highly ionized. Another important reason is addressing decays of well-defined quantum-mechanical systems, such as one-electron ions where all interactions with other electrons are excluded. The largest modifications of nuclear half-lives with respect to neutral atoms have been observed in beta decay of highly charged ions. These studies can be performed solely at ion storage rings and ion traps, because there high atomic charge states can be preserved for extended periods of time (up to several hours). Currently, all experimental results available in this field originate from experiments at the heavy-ion complex GSI in Darmstadt. There, the fragment separator facility FRS allows the production and separation of exotic, highly charged nuclides, which can then be stored and investigated in the storage ring facility ESR. In this review, we present and discuss in particular two-body beta decays, namely bound-state beta decay and orbital electron capture. Although we focus on experiments conducted at GSI, we will also attempt to provide general requirements common to any other experiment in this context. Finally, we address challenging but not yet performed experiments and we give prospects for the new radioactive beam facilities, such as FAIR in Darmstadt, IMP in Lanzhou and RIKEN in Wako.

  17. High current pelletron for ion implantation

    International Nuclear Information System (INIS)

    Schroeder, J.B.

    1989-01-01

    Since 1984, when the first production MeV ion implanter (an NEC model MV-T30) went on-line, interest in versatile electrostatic accelerator systems for MeV ion implantation has grown. The systems use a negative ion source to inject a tandem megavolt accelerator. In early systems the 0.4 mA of charging current from the two Pelletron charging chains in the accelerator was sufficient for the low intensity of beams from the ion source. This 2-chain system, however, is no longer adequate for the much higher beam intensities from today's improved ion sources. A 4-chain charging system, which delivers 1.3 mA to the high voltage terminal, was developed and is in operation in new models of NEC S Series Pelletron accelerators. This paper describes the latest beam performance of 1 MV and 1.7 MW Pelletron accelerators with this new 4-chain charging system. (orig.)

  18. Fueling with edge recycling to high-density in DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, A.W., E-mail: leonard@fusion.gat.com [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States); Elder, J.D. [University of Toronto Institute of Aerospace Studies, Toronto, Canada M3H 5T6 (Canada); Canik, J.M. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Groebner, R.J.; Osborne, T.H. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States)

    2013-07-15

    Pedestal fueling through edge recycling is examined with the interpretive OEDGE code for high-density discharges in DIII-D. A high current, high-density discharge is found to have a similar radial ion flux profile through the pedestal to a lower current, lower density discharge. The higher density discharge, however, has a greater density gradient indicating a pedestal particle diffusion coefficient that scales near linear with 1/I{sub p}. The time dependence of density profile is taken into account in the analysis of a discharge with low frequency ELMs. The time-dependent analysis indicates that the inferred neutral ionization source is inadequate to account for the increase in the density profile between ELMs, implying an inward density convection, or density pinch, near the top of the pedestal.

  19. Dust acoustic shock wave at high dust density

    International Nuclear Information System (INIS)

    Ghosh, Samiran; Sarkar, Susmita; Khan, Manoranjan; Avinash, K.; Gupta, M. R.

    2003-01-01

    Dust acoustic (DA) shock wave at high dust density, i.e., the dust electroacoustic (DEA) or dust Coulomb (DC) shock wave has been investigated incorporating the nonadiabatic dust charge variation. The nonlinear DEA (DC) shock wave is seen to be governed by the Korteweg-de Vries Burger equation, in which the Burger term is proportional to the nonadiabaticity generated dissipation. It is seen that the shock strength decreases but after reaching minimum, it increases as the dust space charge density |q d n d | increases and the shock strength of DA wave is greater than that of DEA (DC) wave. Moreover the DEA (DC) shock width increases appreciably with increase mass m i of the ion component of the dusty plasma but for DA shock wave the effect is weak

  20. Influence of plasma density and plasma sheath dynamics on the ion implantation by plasma immersion technique

    OpenAIRE

    Ensinger, Wolfgang

    1996-01-01

    Influence of plasma density and plasma sheath dynamics on the ion implantation by plasma immersion technique / B. Rauschenbach ... - In: Nuclear instruments and methods in physics research. B. 113. 1996. S. 266-269

  1. Mechanisms for production of highly charged ions

    International Nuclear Information System (INIS)

    McGuire, J.H.

    1987-01-01

    Various experimental data at high collision velocity are interpreted in terms of direct (D) and rearrangement (R) mechanisms for production of multiply charged ions. We consider double ionization in helium by protons, electrons, heavy ions, antiprotons, positrons and photons. Qualitative differences are discussed in the context of the R and D mechanisms. Multiple ionization in many electron atoms is considered as is simultaneous capture and ionization and fragmentation of methane molecules. Some other theoretical methods are briefly discussed. (orig.)

  2. High-Power-Density, High-Energy-Density Fluorinated Graphene for Primary Lithium Batteries

    Directory of Open Access Journals (Sweden)

    Guiming Zhong

    2018-03-01

    Full Text Available Li/CFx is one of the highest-energy-density primary batteries; however, poor rate capability hinders its practical applications in high-power devices. Here we report a preparation of fluorinated graphene (GFx with superior performance through a direct gas fluorination method. We find that the so-called “semi-ionic” C-F bond content in all C-F bonds presents a more critical impact on rate performance of the GFx in comparison with sp2 C content in the GFx, morphology, structure, and specific surface area of the materials. The rate capability remains excellent before the semi-ionic C-F bond proportion in the GFx decreases. Thus, by optimizing semi-ionic C-F content in our GFx, we obtain the optimal x of 0.8, with which the GF0.8 exhibits a very high energy density of 1,073 Wh kg−1 and an excellent power density of 21,460 W kg−1 at a high current density of 10 A g−1. More importantly, our approach opens a new avenue to obtain fluorinated carbon with high energy densities without compromising high power densities.

  3. High Density Lipoprotein and it's Dysfunction.

    Science.gov (United States)

    Eren, Esin; Yilmaz, Necat; Aydin, Ozgur

    2012-01-01

    Plasma high-density lipoprotein cholesterol(HDL-C) levels do not predict functionality and composition of high-density lipoprotein(HDL). Traditionally, keeping levels of low-density lipoprotein cholesterol(LDL-C) down and HDL-C up have been the goal of patients to prevent atherosclerosis that can lead to coronary vascular disease(CVD). People think about the HDL present in their cholesterol test, but not about its functional capability. Up to 65% of cardiovascular death cannot be prevented by putative LDL-C lowering agents. It well explains the strong interest in HDL increasing strategies. However, recent studies have questioned the good in using drugs to increase level of HDL. While raising HDL is a theoretically attractive target, the optimal approach remains uncertain. The attention has turned to the quality, rather than the quantity, of HDL-C. An alternative to elevations in HDL involves strategies to enhance HDL functionality. The situation poses an opportunity for clinical chemists to take the lead in the development and validation of such biomarkers. The best known function of HDL is the capacity to promote cellular cholesterol efflux from peripheral cells and deliver cholesterol to the liver for excretion, thereby playing a key role in reverse cholesterol transport (RCT). The functions of HDL that have recently attracted attention include anti-inflammatory and anti-oxidant activities. High antioxidant and anti-inflammatory activities of HDL are associated with protection from CVD.This review addresses the current state of knowledge regarding assays of HDL functions and their relationship to CVD. HDL as a therapeutic target is the new frontier with huge potential for positive public health implications.

  4. Determination of plasma density from data on the ion current to cylindrical and planar probes

    Energy Technology Data Exchange (ETDEWEB)

    Voloshin, D. G., E-mail: dvoloshin@mics.msu.su; Vasil’eva, A. N.; Kovalev, A. S.; Mankelevich, Yu. A.; Rakhimova, T. V. [Moscow State University, Skobeltsyn Nuclear Physics Institute (Russian Federation)

    2016-12-15

    To improve probe methods of plasma diagnostics, special probe measurements were performed and numerical models describing ion transport to a probe with allowance for collisions were developed. The current–voltage characteristics of cylindrical and planar probes were measured in an RF capacitive discharge in argon at a frequency of 81 MHz and plasma densities of 10{sup 10}–10{sup 11} cm{sup –3}, typical of modern RF reactors. 1D and 2D numerical models based on the particle-in-cell method with Monte Carlo collisions for simulating ion motion and the Boltzmann equilibrium for electrons are developed to describe current collection by a probe. The models were used to find the plasma density from the ion part of the current–voltage characteristic, study the effect of ion collisions, and verify simplified approaches to determining the plasma density. A 1D hydrodynamic model of the ion current to a cylindrical probe with allowance for ion collisions is proposed. For a planar probe, a method to determine the plasma density from the averaged numerical results is developed. A comparative analysis of different approaches to calculating the plasma density from the ion current to a probe is performed.

  5. Predicted precision of ion temperature and impurity fractional density measurements using the JET collective scattering diagnostic

    International Nuclear Information System (INIS)

    Orsitto, F.

    1992-11-01

    In a previous investigation the possibility of measuring the bulk ion temperature was considered in detail, in the context of the proposed Thomson scattering diagnostic for fast ions and alpha particles in the Joint European Torus project. In this report we give an affirmative answer to the question of whether good precision can be obtained in the simultaneous determination of the temperatures and densities of plasma ions from a collective scattering experiment provided some conditions are satisfied. (Author)

  6. Measurement of the density profile of pure and seeded molecular beams by femtosecond ion imaging

    NARCIS (Netherlands)

    Meng, C.; Janssen, M.H.M.

    2015-01-01

    Here, we report on femtosecond ion imaging experiments to measure the density profile of a pulsed supersonic molecular beam. Ion images are measured for both a molecular beam and bulk gas under identical experimental conditions via femtosecond multiphoton ionization of Xe atoms. We report the

  7. Damping-Growth Transition for Ion-Acoustic Waves in a Density Gradient

    DEFF Research Database (Denmark)

    D'Angelo, N.; Michelsen, Poul; Pécseli, Hans

    1975-01-01

    A damping-growth transition for ion-acoustic waves propagating in a nonuniform plasma (e-folding length for the density ln) is observed at a wavelength λ∼2πln. This result supports calculations performed in connection with the problem of heating of the solar corona by ion-acoustic waves generated...

  8. High Spectral Density Optical Communication Technologies

    CERN Document Server

    Nakazawa, Masataka; Miyazaki, Tetsuya

    2010-01-01

    The latest hot topics of high-spectral density optical communication systems using digital coherent optical fibre communication technologies are covered by this book. History and meaning of a "renaissance" of the technology, requirements to the Peta-bit/s class "new generation network" are also covered in the first part of this book. The main topics treated are electronic and optical devices, digital signal processing including forward error correction, modulation formats as well as transmission and application systems. The book serves as a reference to researchers and engineers.

  9. Measurement of the density profile of pure and seeded molecular beams by femtosecond ion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Congsen [LaserLaB Amsterdam, VU University Amsterdam, de Boelelaan 1083, 1081 HV Amsterdam (Netherlands); Department of Physics, National University of Defense Technology, Changsha 410073 (China); Janssen, Maurice H. M. [LaserLaB Amsterdam, VU University Amsterdam, de Boelelaan 1083, 1081 HV Amsterdam (Netherlands)

    2015-02-15

    Here, we report on femtosecond ion imaging experiments to measure the density profile of a pulsed supersonic molecular beam. Ion images are measured for both a molecular beam and bulk gas under identical experimental conditions via femtosecond multiphoton ionization of Xe atoms. We report the density profile of the molecular beam, and the measured absolute density is compared with theoretical calculations of the centre line beam density. Subsequently, we discuss reasons accounting for the differences between measurements and calculations and propose that strong skimmer interference is the most probable cause for the differences. Furthermore, we report on experiments measuring the centre line density of seeded supersonic beams. The femtosecond ion images show that seeding the heavy Xe atom at low relative seed fractions (1%-10%) in a light carrier gas like Ne results in strong relative enhancements of up to two orders of magnitude.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-12-15

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

  11. High density plasmas and new diagnostics: An overview (invited)

    International Nuclear Information System (INIS)

    Celona, L.; Gammino, S.; Mascali, D.

    2016-01-01

    One of the limiting factors for the full understanding of Electron Cyclotron Resonance Ion Sources (ECRISs) fundamental mechanisms consists of few types of diagnostic tools so far available for such compact machines. Microwave-to-plasma coupling optimisation, new methods of density overboost provided by plasma wave generation, and magnetostatic field tailoring for generating a proper electron energy distribution function, suitable for optimal ion beams formation, require diagnostic tools spanning across the entire electromagnetic spectrum from microwave interferometry to X-ray spectroscopy; these methods are going to be implemented including high resolution and spatially resolved X-ray spectroscopy made by quasi-optical methods (pin-hole cameras). The ion confinement optimisation also requires a complete control of cold electrons displacement, which can be performed by optical emission spectroscopy. Several diagnostic tools have been recently developed at INFN-LNS, including “volume-integrated” X-ray spectroscopy in low energy domain (2-30 keV, by using silicon drift detectors) or high energy regime (>30 keV, by using high purity germanium detectors). For the direct detection of the spatially resolved spectral distribution of X-rays produced by the electronic motion, a “pin-hole camera” has been developed also taking profit from previous experiences in the ECRIS field. The paper will give an overview of INFN-LNS strategy in terms of new microwave-to-plasma coupling schemes and advanced diagnostics supporting the design of new ion sources and for optimizing the performances of the existing ones, with the goal of a microwave-absorption oriented design of future machines

  12. Evaluation of the radiation resistance of high-density polyethylene

    International Nuclear Information System (INIS)

    Dougherty, D.R.; Adams, J.W.; Barletta, R.R.

    1984-03-01

    Mechanical tests following gamma irradiation and creep tests during irradiation have been conducted on high-density polyethylene (HDPE) to provide data to help assess the adequacy of this material for use in high integrity containers (HICs). Two types of HDPE, a highly cross-linked rotationally molded material and a non-cross-linked blow molded material, were used in these tests. Gamma-ray irradiations were performed at several dose rates in environments of air, Barnwell and Hanford backfill soils, and ion-exchange resins. The results of tensile and bend tests on these materials following irradiation are presented along with results on creep during irradiation. 8 references, 9 figures, 2 tables

  13. Low-emittance uniform density Cs+ sources for heavy ion fusion accelerators studies

    International Nuclear Information System (INIS)

    Eylon, S.; Henestroza, E.; Garvey, T.; Johnson, R.; Chupp, W.

    1991-04-01

    Low-emittance (high-brightness) Cs + thermionic sources were developed for the heavy ion induction linac experiment MBE-4 at LBL. The MBE-4 linac accelerates four 10 mA beams from 200 ke V to 900 ke V while amplifying the current up to a factor of nine. Recent studies of the transverse beam dynamics suggested that characteristics of the injector geometry were contributing to the normalized transverse emissions growth. Phase-space and current density distribution measurements of the beam extracted from the injector revealed overfocusing of the outermost rays causing a hollow density profile. We shall report on the performance of a 5 mA scraped beam source (which eliminates the outermost beam rays in the diode) and on the design of an improved 10 mA source. The new source is based on EGUN calculations which indicated that a beam with good emissions and uniform current density could be obtained by modifying the cathode Pierce electrodes and using a spherical emitting surface. The measurements of the beam current density profile on a test stand were found to be in agreement with the numerical simulations. 3 refs., 6 figs

  14. High-density hybrid interconnect methodologies

    International Nuclear Information System (INIS)

    John, J.; Zimmermann, L.; Moor, P.De; Hoof, C.Van

    2003-01-01

    Full text: The presentation gives an overview of the state-of-the-art of hybrid integration and in particular the IMEC technological approaches that will be able to address future hybrid detector needs. The dense hybrid flip-chip integration of an array of detectors and its dedicated readout electronics can be achieved with a variety of solderbump techniques such as pure Indium or Indium alloys, Ph-In, Ni/PbSn, but also conducting polymers... Particularly for cooled applications or ultra-high density applications, Indium solderbump technology (electroplated or evaporated) is the method of choice. The state-of-the-art of solderbump technologies that are to a high degree independent of the underlying detector material will be presented and examples of interconnect densities between 5x1E4cm-2 and 1x1E6 cm-2 will be demonstrated. For several classes of detectors, flip-chip integration is not allowed since the detectors have to be illuminated from the top. This applies to image sensors for EUV applications such as GaN/AlGaN based detectors and to MEMS-based sensors. In such cases, the only viable interconnection method has to be through the (thinned) detector wafer followed by a solderbump-based integration. The approaches for dense and ultra-dense through-the-wafer interconnect 'vias' will be presented and wafer thinning approaches will be shown

  15. Plasma Diagnostics in High Density Reactors

    International Nuclear Information System (INIS)

    Daltrini, A. M.; Moshkalyov, S.; Monteiro, M. J. R.; Machida, M.; Kostryukov, A.; Besseler, E.; Biasotto, C.; Diniz, J. A.

    2006-01-01

    Langmuir electric probes and optical emission spectroscopy diagnostics were developed for applications in high density plasmas. These diagnostics were employed in two plasma sources: an electron cyclotron resonance (ECR) plasma and an RF driven inductively coupled plasma (ICP) plasma. Langmuir probes were tested using a number of probing dimensions, probe tip materials, circuits for probe bias and filters. Then, the results were compared with the optical spectroscopy measurements. With these diagnostics, analyses of various plasma processes were performed in both reactors. For example, it has been shown that species like NH radicals generated in gas phase can have critical impact on films deposited by ECR plasmas. In the ICP source, plasmas in atomic and molecular gases were shown to have different spatial distributions, likely due to nonlocal electron heating. The low-to-high density transitions in the ICP plasma were also studied. The role of metastables is shown to be significant in Ar plasmas, in contrast to plasmas with additions of molecular gases

  16. High Energy Density Sciences with High Power Lasers at SACLA

    Science.gov (United States)

    Kodama, Ryosuke

    2013-10-01

    One of the interesting topics on high energy density sciences with high power lasers is creation of extremely high pressures in material. The pressures of more than 0.1 TPa are the energy density corresponding to the chemical bonding energy, resulting in expectation of dramatic changes in the chemical reactions. At pressures of more than TPa, most of material would be melted on the shock Hugoniot curve. However, if the temperature is less than 1eV or lower than a melting point at pressures of more than TPa, novel solid states of matter must be created through a pressured phase transition. One of the interesting materials must be carbon. At pressures of more than TPa, the diamond structure changes to BC and cubic at more than 3TPa. To create such novel states of matter, several kinds of isentropic-like compression techniques are being developed with high power lasers. To explore the ``Tera-Pascal Science,'' now we have a new tool which is an x-ray free electron laser as well as high power lasers. The XFEL will clear the details of the HED states and also efficiently create hot dense matter. We have started a new project on high energy density sciences using an XFEL (SACLA) in Japan, which is a HERMES (High Energy density Revolution of Matter in Extreme States) project.

  17. Calculation of large ion densities under HVdc transmission lines by the finite difference method

    International Nuclear Information System (INIS)

    Suda, Tomotaka; Sunaga, Yoshitaka

    1995-01-01

    A calculation method for large ion densities (charged aerosols) under HVdc transmission lines was developed considering both the charging mechanism of aerosols by small ions and the drifting process by wind. Large ion densities calculated by this method agreed well with the ones measured under the Shiobara HVdc test line on the lateral profiles at ground level up to about 70m downwind from the line. Measured values decreased more quickly than calculated ones farther downwind from the line. Considering the effect of point discharge from ground cover (earth corona) improved the agreement in the farther downwind region

  18. High Tap Density Spherical Li[Ni0.5Mn0.3Co0.2]O2 Cathode Material Synthesized via Continuous Hydroxide Coprecipitation Method for Advanced Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Shunyi Yang

    2012-01-01

    Full Text Available Spherical [Ni0.5Mn0.3Co0.2](OH2 precursor with narrow size distribution and high tap density has been successfully synthesized by a continuous hydroxide coprecipitation, and Li[Ni0.5Mn0.3Co0.2]O2 is then prepared by mixing the precursor with 6% excess Li2CO3 followed by calcinations. The tap density of the obtained Li[Ni0.5Mn0.3Co0.2]O2 powder is as high as 2.61 g cm−3. The powders are characterized by X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS, scanning electron microscope (SEM, particle size distribution (PSD, and charge/discharge cycling. The XRD studies show that the prepared Li[Ni0.5Mn0.3Co0.2]O2 has a well-ordered layered structure without any impurity phases. Good packing properties of spherical secondary particles (about 12 μm consisted of a large number of tiny-thin plate-shape primary particles (less than 1 μm, which can be identified from the SEM observations. In the voltage range of 3.0–4.3 V and 2.5–4.6 V, Li[Ni0.5Mn0.3Co0.2]O2 delivers the initial discharge capacity of approximately 175 and 214 mAh g−1 at a current density of 32 mA g−1, and the capacity retention after 50 cycles reaches 98.8% and 90.2%, respectively. Besides, it displays good high-temperature characteristics and excellent rate capability.

  19. High current ion source development at Frankfurt

    Energy Technology Data Exchange (ETDEWEB)

    Volk, K.; Klein, H.; Lakatos, A.; Maaser, A.; Weber, M. [Frankfurt Univ. (Germany). Inst. fuer Angewandte Physik

    1995-11-01

    The development of high current positive and negative ion sources is an essential issue for the next generation of high current linear accelerators. Especially, the design of the European Spallation Source facility (ESS) and the International Fusion Material Irradiation Test Facility (IFMIF) have increased the significance of high brightness hydrogen and deuterium sources. As an example, for the ESS facility, two H{sup -}-sources each delivering a 70 mA H{sup -}-beam in 1.45 ms pulses at a repetition rate of 50 Hz are necessary. A low emittance is another important prerequisite. The source must operate, while meeting the performance requirements, with a constancy and reliability over an acceptable period of time. The present paper summarizes the progress achieved in ion sources development of intense, single charge, positive and negative ion beams. (author) 16 figs., 7 refs.

  20. High current ion source development at Frankfurt

    International Nuclear Information System (INIS)

    Volk, K.; Klein, H.; Lakatos, A.; Maaser, A.; Weber, M.

    1995-01-01

    The development of high current positive and negative ion sources is an essential issue for the next generation of high current linear accelerators. Especially, the design of the European Spallation Source facility (ESS) and the International Fusion Material Irradiation Test Facility (IFMIF) have increased the significance of high brightness hydrogen and deuterium sources. As an example, for the ESS facility, two H - -sources each delivering a 70 mA H - -beam in 1.45 ms pulses at a repetition rate of 50 Hz are necessary. A low emittance is another important prerequisite. The source must operate, while meeting the performance requirements, with a constancy and reliability over an acceptable period of time. The present paper summarizes the progress achieved in ion sources development of intense, single charge, positive and negative ion beams. (author) 16 figs., 7 refs

  1. Effect of electrode for producing the highly charged heavy ions from RIKEN 18 GHz electron cyclotron resonance ion source

    International Nuclear Information System (INIS)

    Kurita, Tetsuro; Nakagawa, Takahide; Kidera, Masanori

    1999-01-01

    We successfully produced the intense beam of highly charged Kr ions using an electrode. Under the pulsed mode operation, we found that the depth of the plasma potential dip strongly depends on the duration of the microwave and takes about 40 ms to reach the equilibrium state. Taking these results into account, we compared the beam intensities of highly charged Kr ions with and without the use of an electrode under the pulsed mode operation. We observed that the density of highly charged Kr ions and ion confinement time increase with increasing mirror magnetic field strength. The plasma potential dip becomes shallower with insertion of the electrode. Consequently, when we increase the mirror magnetic field strength and insert the electrode into the plasma, the beam intensities of highly charged ions increase. (author)

  2. Magnetically filtered Faraday probe for measuring the ion current density profile of a Hall thruster

    International Nuclear Information System (INIS)

    Rovey, Joshua L.; Walker, Mitchell L.R.; Gallimore, Alec D.; Peterson, Peter Y.

    2006-01-01

    The ability of a magnetically filtered Faraday probe (MFFP) to obtain the ion current density profile of a Hall thruster is investigated. The MFFP is designed to eliminate the collection of low-energy, charge-exchange (CEX) ions by using a variable magnetic field as an ion filter. In this study, a MFFP, Faraday probe with a reduced acceptance angle (BFP), and nude Faraday probe are used to measure the ion current density profile of a 5 kW Hall thruster operating over the range of 300-500 V and 5-10 mg/s. The probes are evaluated on a xenon propellant Hall thruster in the University of Michigan Large Vacuum Test Facility at operating pressures within the range of 4.4x10 -4 Pa Xe (3.3x10 -6 Torr Xe) to 1.1x10 -3 Pa Xe (8.4x10 -6 Torr Xe) in order to study the ability of the Faraday probe designs to filter out CEX ions. Detailed examination of the results shows that the nude probe measures a greater ion current density profile than both the MFFP and BFP over the range of angular positions investigated for each operating condition. The differences between the current density profiles obtained by each probe are attributed to the ion filtering systems employed. Analysis of the results shows that the MFFP, operating at a +5 A solenoid current, provides the best agreement with flight-test data and across operating pressures

  3. Comparison of measured and modelled negative hydrogen ion densities at the ECR-discharge HOMER

    Science.gov (United States)

    Rauner, D.; Kurutz, U.; Fantz, U.

    2015-04-01

    As the negative hydrogen ion density nH- is a key parameter for the investigation of negative ion sources, its diagnostic quantification is essential in source development and operation as well as for fundamental research. By utilizing the photodetachment process of negative ions, generally two different diagnostic methods can be applied: via laser photodetachment, the density of negative ions is measured locally, but only relatively to the electron density. To obtain absolute densities, the electron density has to be measured additionally, which induces further uncertainties. Via cavity ring-down spectroscopy (CRDS), the absolute density of H- is measured directly, however LOS-averaged over the plasma length. At the ECR-discharge HOMER, where H- is produced in the plasma volume, laser photodetachment is applied as the standard method to measure nH-. The additional application of CRDS provides the possibility to directly obtain absolute values of nH-, thereby successfully bench-marking the laser photodetachment system as both diagnostics are in good agreement. In the investigated pressure range from 0.3 to 3 Pa, the measured negative hydrogen ion density shows a maximum at 1 to 1.5 Pa and an approximately linear response to increasing input microwave powers from 200 up to 500 W. Additionally, the volume production of negative ions is 0-dimensionally modelled by balancing H- production and destruction processes. The modelled densities are adapted to the absolute measurements of nH- via CRDS, allowing to identify collisions of H- with hydrogen atoms (associative and non-associative detachment) to be the dominant loss process of H- in the plasma volume at HOMER. Furthermore, the characteristic peak of nH- observed at 1 to 1.5 Pa is identified to be caused by a comparable behaviour of the electron density with varying pressure, as ne determines the volume production rate via dissociative electron attachment to vibrationally excited hydrogen molecules.

  4. Frontiers in pulse-power-based high energy density plasma physics and its applications

    International Nuclear Information System (INIS)

    Horioka, Kazuhiko

    2008-03-01

    The papers in this volume of report were presented at the Symposium on Frontiers in Pulse-power-based High Energy Density Physics' held by National Institute for Fusion Science. The topics include the present status of high energy density plasma researches, extreme ultraviolet sources, intense radiation sources, high power ion beams, and R and D of related pulse power technologies. The 13 of the presented papers are indexed individually. (J.P.N.)

  5. High density high-TC ceramic superconductors by hot pressing

    International Nuclear Information System (INIS)

    Mak, S.; Chaklader, A.C.D.

    1989-01-01

    High density and high T C superconductor specimens, YBa 2 Cu 3 O x , have been produced by hot-pressing. The factors studied are the effect of hot pressing on the density, the oxygen stoichiometry, the crystal structure, and the critical temperature. Hot pressing followed by heat treatment increased the density of the specimen to 93%. The hot pressing itself did not significantly affect the oxygen content in the specimen, and although the crystal structure appeared to be orthorhombic, the specimens were not superconducting above liquid nitrogen temperature. The superconductivity was restored after head treatment in oxygen. The highest critical temperature (T C ) of the hot pressed pellets was 82K, which was slightly lower than the T C that could be obtained with the cold pressed/sintered pellets. (6 refs., 5 figs., tab.)

  6. High power switches for ion induction linacs

    International Nuclear Information System (INIS)

    Humphries, S.; Savage, M.; Saylor, W.B.

    1985-01-01

    The success of linear induction ion accelerators for accelerator inertial fusion (AIF) applications depends largely on innovations in pulsed power technology. There are tight constraints on the accuracy of accelerating voltage waveforms to maintain a low momentum spread. Furthermore, the non-relativistic ion beams may be subject to a klystronlike interaction with the accelerating cavities, leading to enhanced momentum spread. In this paper, we describe a novel high power switch with a demonstrated ability to interrupt 300 A at 20 kV in less than 60 ns. The switch may allow the replacement of pulse modulators in linear induction accelerators with hard tube pulsers. A power system based on a hard tube pulser could solve the longitudinal instability problem while maintaining high energy transfer efficiency. The problem of longitudinal beam control in ion induction linacs is reviewed in Section 2. Section 3 describes the principles of the plasma flow switch. Experimental results are summarized in Section 4

  7. High power switches for ion induction linacs

    International Nuclear Information System (INIS)

    Humphries, S. Jr.; Savage, M.; Saylor, W.B.

    1985-01-01

    The success of linear induction ion accelerators for accelerator inertial fusion (AIF) applications depends largely on innovations in pulsed power technology. There are tight constraints on the accuracy of accelerating voltage waveforms to maintain a low momentum spread. Furthermore, the non-relativistic ion beams may be subject to a klystron-like interaction with the accelerating cavities leading to enhanced momentum spread. In this paper, the author describe a novel high power switch with a demonstrated ability to interrupt 300 A at 20 kV in less than 60 ns. The switch may allow the replacement of pulse modulators in linear induction accelerators with hard tube pulsers. A power system based on a hard tube pulser could solve the longitudinal instability problem while maintaining high energy transfer efficiency. The problem of longitudinal beam control in ion induction linacs is reviewed in Section 2. Section 3 describes the principles of the plasma flow switch. Experimental results are summarized in Section 4

  8. Experiments on the indirect heating of low density aerogels for applications in heavy ion stopping in plasma

    International Nuclear Information System (INIS)

    Rosmej, O.N.; Blazevic, A.; Suslov, N.; Kunin, A.; Pinegin, A.; Schaefer, D.; Nisius, Th.; Zhao, Y.; Rinecker, T.; Wiechula, J.

    2010-01-01

    Complete text of publication follows. The unique combination of a Petawatt High-Energy Laser System for Ion beam eXperiments - 'Phelix' (Nd:glass, 1053 nm, 300-500 J, 1-15 ns) and intense heavy ion beams of the UNILAC accelerator at GSI-Darmstadt allow creating and probing of hot plasma with a density of some percentage of solid-state density. The experimental program aims at the investigation of fundamental features of heavy ion stopping in ionized matter in view of promising applications for the Heavy Ion Fusion and astrophysics. For combined experiments on the interaction of heavy ion beams with ionized matter (GSI) a high density plasma target with homogeneous in time (∼ 5 ns) and space (∼ 1 mm) plasma parameters in required. For these purposes we are developing the combined target which consists on the Gold hohlraum (converter) and low Z foam target heated by the hohlraum radiation before probed by an ion bunch. Foam targets are rather promising due to the effective conversion of the deposited radiation energy into the internal plasma energy and slow hydrodynamic response on the heating. Direct irradiation of the Gold converter walls with a nanosecond pulse delivered by the PHELIX-laser system (GSI) leads to hohlraum radiation spectra in the photon energy range of 50-500 eV. Expected temperatures of the foam targets heated by this radiation amount to 20-30 eV at electron densities of 10 21 cm -3 . The results of the last hohlraum experiments carried out at PHELIX-laser energies of 200-250 J will be presented. In experiments the hohlraum radiation field, the conversion efficiency of the laser energy into soft X-rays, duration of the soft X-ray pulse, and parameters of the heated with X-rays foam targets have been measured. Acknowledgements. This work is supported by ISTC 2264 grant.

  9. Nanotechnology for Synthetic High Density Lipoproteins

    Science.gov (United States)

    Luthi, Andrea J.; Patel, Pinal C.; Ko, Caroline H.; Mutharasan, R. Kannan; Mirkin, Chad A.; Thaxton, C. Shad

    2014-01-01

    Atherosclerosis is the disease mechanism responsible for coronary heart disease (CHD), the leading cause of death worldwide. One strategy to combat atherosclerosis is to increase the amount of circulating high density lipoproteins (HDL), which transport cholesterol from peripheral tissues to the liver for excretion. The process, known as reverse cholesterol transport, is thought to be one of the main reasons for the significant inverse correlation observed between HDL blood levels and the development of CHD. This article highlights the most common strategies for treating atherosclerosis using HDL. We further detail potential treatment opportunities that utilize nanotechnology to increase the amount of HDL in circulation. The synthesis of biomimetic HDL nanostructures that replicate the chemical and physical properties of natural HDL provides novel materials for investigating the structure-function relationships of HDL and for potential new therapeutics to combat CHD. PMID:21087901

  10. Ground state of high-density matter

    Science.gov (United States)

    Copeland, ED; Kolb, Edward W.; Lee, Kimyeong

    1988-01-01

    It is shown that if an upper bound to the false vacuum energy of the electroweak Higgs potential is satisfied, the true ground state of high-density matter is not nuclear matter, or even strange-quark matter, but rather a non-topological soliton where the electroweak symmetry is exact and the fermions are massless. This possibility is examined in the standard SU(3) sub C tensor product SU(2) sub L tensor product U(1) sub Y model. The bound to the false vacuum energy is satisfied only for a narrow range of the Higgs boson masses in the minimal electroweak model (within about 10 eV of its minimum allowed value of 6.6 GeV) and a somewhat wider range for electroweak models with a non-minimal Higgs sector.

  11. High power density carbonate fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Yuh, C.; Johnsen, R.; Doyon, J.; Allen, J. [Energy Research Corp., Danbury, CT (United States)

    1996-12-31

    Carbonate fuel cell is a highly efficient and environmentally clean source of power generation. Many organizations worldwide are actively pursuing the development of the technology. Field demonstration of multi-MW size power plant has been initiated in 1996, a step toward commercialization before the turn of the century, Energy Research Corporation (ERC) is planning to introduce a 2.85MW commercial fuel cell power plant with an efficiency of 58%, which is quite attractive for distributed power generation. However, to further expand competitive edge over alternative systems and to achieve wider market penetration, ERC is exploring advanced carbonate fuel cells having significantly higher power densities. A more compact power plant would also stimulate interest in new markets such as ships and submarines where space limitations exist. The activities focused on reducing cell polarization and internal resistance as well as on advanced thin cell components.

  12. High-energy ion tail formation due to ion acoustic turbulence in the TRIAM-1 tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Kazuo; Hiraki, Naoji; Nakamura, Yukio; Itoh, Satoshi [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics

    1982-02-01

    The two-component ion energy spectra observed in the TRIAM-1 tokamak are explained as a result of the high-energy ion tail formation due to ion acoustic turbulence driven by a toroidal current pulse for turbulent heating.

  13. Fundamental processes determining the highly charged ion production in ECR ion sources

    International Nuclear Information System (INIS)

    Shirkov, G.D.

    1992-01-01

    The ion confinement and loss conditions in the open magnetic traps have been analyzed in this article. In EGRIS the the ions are confined in the negative potential well. The simultaneous application of ion cooling and pulse regime is proposed for pulse injection of highly charged ions in heavy ion accelerators and storage rings. 14 refs.; 3 figs

  14. High repetition rate intense ion beam source

    International Nuclear Information System (INIS)

    Hammer, D.A.; Glidden, S.C.; Noonan, B.

    1992-01-01

    This final report describes a ≤ 150kV, 40kA, 100ns high repetition rate pulsed power system and intense ion beam source which is now in operation at Cornell University. Operation of the Magnetically-controlled Anode Plasma (MAP) ion diode at > 100Hz (burst mode for up to 10 pulse bursts) provides an initial look at repetition rate limitations of both the ion diode and beam diagnostics. The pulsed power systems are capable of ≥ 1kHz operation (up to 10 pulse bursts), but ion diode operation was limited to ∼100Hz because of diagnostic limitations. By varying MAP diode operating parameters, ion beams can be extracted at a few 10s of keV or at up to 150keV, the corresponding accelerating gap impedance ranging from about 1Ω to about 10Ω. The ability to make hundreds of test pulses per day at an average repetition rate of about 2 pulses per minute permits statistical analysis of diode operation as a function of various parameters. Most diode components have now survived more than 10 4 pulses, and the design and construction of the various pulsed power components of the MAP diode which have enabled us to reach this point are discussed. A high speed data acquisition system and companion analysis software capable of acquiring pulse data at 1ms intervals (in bursts of up to 10 pulses) and processing it in ≤ min is described

  15. Anomalous evolution of Ar metastable density with electron density in high density Ar discharge

    International Nuclear Information System (INIS)

    Park, Min; Chang, Hong-Young; You, Shin-Jae; Kim, Jung-Hyung; Shin, Yong-Hyeon

    2011-01-01

    Recently, an anomalous evolution of argon metastable density with plasma discharge power (electron density) was reported [A. M. Daltrini, S. A. Moshkalev, T. J. Morgan, R. B. Piejak, and W. G. Graham, Appl. Phys. Lett. 92, 061504 (2008)]. Although the importance of the metastable atom and its density has been reported in a lot of literature, however, a basic physics behind the anomalous evolution of metastable density has not been clearly understood yet. In this study, we investigated a simple global model to elucidate the underlying physics of the anomalous evolution of argon metastable density with the electron density. On the basis of the proposed simple model, we reproduced the anomalous evolution of the metastable density and disclosed the detailed physics for the anomalous result. Drastic changes of dominant mechanisms for the population and depopulation processes of Ar metastable atoms with electron density, which take place even in relatively low electron density regime, is the clue to understand the result.

  16. Ion Channel Trafficking: Control of Ion Channel Density as a Target for Arrhythmias?

    Directory of Open Access Journals (Sweden)

    Elise Balse

    2017-10-01

    Full Text Available The shape of the cardiac action potential (AP is determined by the contributions of numerous ion channels. Any dysfunction in the proper function or expression of these ion channels can result in a change in effective refractory period (ERP and lead to arrhythmia. The processes underlying the correct targeting of ion channels to the plasma membrane are complex, and have not been fully characterized in cardiac myocytes. Emerging evidence highlights ion channel trafficking as a potential causative factor in certain acquired and inherited arrhythmias, and therapies which target trafficking as opposed to pore block are starting to receive attention. In this review we present the current evidence for the mechanisms which underlie precise control of cardiac ion channel trafficking and targeting.

  17. Carbonation of wollastonite(001) competing hydration: microscopic insights from ion spectroscopy and density functional theory.

    Science.gov (United States)

    Longo, Roberto C; Cho, Kyeongjae; Brüner, Philipp; Welle, Alexander; Gerdes, Andreas; Thissen, Peter

    2015-03-04

    In this paper, we report about the influence of the chemical potential of water on the carbonation reaction of wollastonite (CaSiO3) as a model surface of cement and concrete. Total energy calculations based on density functional theory combined with kinetic barrier predictions based on nudge elastic band method show that the exposure of the water-free wollastonite surface to CO2 results in a barrier-less carbonation. CO2 reacts with the surface oxygen and forms carbonate (CO3(2-)) complexes together with a major reconstruction of the surface. The reaction comes to a standstill after one carbonate monolayer has been formed. In case one water monolayer is covering the wollastonite surface, the carbonation is no more barrier-less, yet ending in a localized monolayer. Covered with multilayers of water, the thermodynamic ground state of the wollastonite completely changes due to a metal-proton exchange reaction (also called early stage hydration) and Ca(2+) ions are partially removed from solid phase into the H2O/wollastonite interface. Mobile Ca(2+) reacts again with CO2 and forms carbonate complexes, ending in a delocalized layer. By means of high-resolution time-of-flight secondary-ion mass spectrometry images, we confirm that hydration can lead to a partially delocalization of Ca(2+) ions on wollastonite surfaces. Finally, we evaluate the impact of our model surface results by the meaning of low-energy ion-scattering spectroscopy combined with careful discussion about the competing reactions of carbonation vs hydration.

  18. Atomic physics with highly charged ions

    International Nuclear Information System (INIS)

    Richard, P.

    1991-08-01

    This report discusses: One electron outer shell processes in fast ion-atom collisions; role of electron-electron interaction in two-electron processes; multi-electron processes at low energy; multi-electron processes at high energy; inner shell processes; molecular fragmentation studies; theory; and, JRM laboratory operations

  19. Experiments on very high energy heavy ions

    International Nuclear Information System (INIS)

    Willis, W.J.

    1981-01-01

    In this paper I describe experimental techniques which could be used to investigate central collision of very high energy heavy ions. For my purposes, the energy range is defined by the number of pions produced, Nsub(π) >> 100, and consequently Nsub(π) >> Nsub(nucleon). In this regime we may expect that new phenomena will appear. (orig.)

  20. Heavy ion fragmentation in high energy

    International Nuclear Information System (INIS)

    Nemes, M.C.

    1985-01-01

    A review is made on the theoretical aspects of heavy ion collisions at high energies. A comparison with several experimental data obtained in a large variety of experiments is present. An emphasis is given on the basis of Glauber's theory of scattering. (L.C.) [pt

  1. Prospects for high energy heavy ion accelerators

    International Nuclear Information System (INIS)

    Leemann, C.

    1979-03-01

    The acceleration of heavy ions to relativistic energies (T greater than or equal to 1 GeV/amu) at the beam intensities required for fundamental research falls clearly in the domain of synchrotons. Up to date, such beams have been obtained from machines originally designed as proton acccelerators by means of modified RF-programs, improved vacuum and, most importantly, altered or entirely new injector systems. Similarly, for the future, substantial changes in synchrotron design itself are not foreseen, but rather the judicious application and development of presently known principles and technologies and a choice of parameters optimized with respect to the peculiarities of heavy ions. The low charge to mass ratio, q/A, of very heavy ions demands that superconducting magnets be considered in the interest of the highest energies for a given machine size. Injector brightness will continue to be of highest importance, and although space charge effects such as tune shifts will be increased by a factor q 2 /A compared with protons, advances in linac current and brightness, rather than substantially higher energies are required to best utilize a given synchrotron acceptance. However, high yeilds of fully stripped, very heavy ions demand energies of a few hundred MeV/amu, thus indicating the need for a booster synchrotron, although for entirely different reasons than in proton facilities. Finally, should we consider colliding beams, the high charge of heavy ions will impose severe current limitations and put high demands on system design with regard to such quantities as e.g., wall impedances or the ion induced gas desorption rate, and advanced concepts such as low β insertions with suppressed dispersion and very small crossing angles will be essential to the achievement of useful luminosities

  2. Fast-ion transport in low density L-mode plasmas at TCV using FIDA spectroscopy and the TRANSP code

    DEFF Research Database (Denmark)

    Geiger, B.; Karpushov, A.; Duval, B. P.

    2017-01-01

    Experiments with the new neutral beam injection source of TCV have been performed with high fast-ion fractions (>20%) that exhibit a clear reduction of the loop voltage and a clear increase of the plasma pressure in on- and off-axis heating configurations. However, good quantitative......, a newly installed fast-ion D-alpha (FIDA) spectroscopy system measures strong passive radiation and, hence, indicates the presence of high background neutral densities such that charge-exchange losses are substantial. Also the active radiation measured with the FIDA diagnostic, as well as data from...... a neutral particle analyzer, suggest strong fast-ion losses and large neutral densities. The large neutral densities can be justified since high electron temperatures (3–4 keV), combined with low electron densities (about 2 X 1019 m−3) yield long mean free paths of the neutrals which are penetrating from...

  3. High-field, high-density tokamak power reactor

    International Nuclear Information System (INIS)

    Cohn, D.R.; Cook, D.L.; Hay, R.D.; Kaplan, D.; Kreischer, K.; Lidskii, L.M.; Stephany, W.; Williams, J.E.C.; Jassby, D.L.; Okabayashi, M.

    1977-11-01

    A conceptual design of a compact (R 0 = 6.0 m) high power density (average P/sub f/ = 7.7 MW/m 3 ) tokamak demonstration power reactor has been developed. High magnetic field (B/sub t/ = 7.4 T) and moderate elongation (b/a = 1.6) permit operation at the high density (n(0) approximately 5 x 10 14 cm -3 ) needed for ignition in a relatively small plasma, with a spatially-averaged toroidal beta of only 4%. A unique design for the Nb 3 Sn toroidal-field magnet system reduces the stress in the high-field trunk region, and allows modularization for simpler disassembly. The modest value of toroidal beta permits a simple, modularized plasma-shaping coil system, located inside the TF coil trunk. Heating of the dense central plasma is attained by the use of ripple-assisted injection of 120-keV D 0 beams. The ripple-coil system also affords dynamic control of the plasma temperature during the burn period. A FLIBE-lithium blanket is designed especially for high-power-density operation in a high-field environment, and gives an overall tritium breeding ratio of 1.05 in the slowly pumped lithium

  4. High energy ion implantation for IC processing

    International Nuclear Information System (INIS)

    Oosterhoff, S.

    1986-01-01

    In this thesis the results of fundamental research on high energy ion implantation in silicon are presented and discussed. The implantations have been carried out with the 500 kV HVEE ion implantation machine, that was acquired in 1981 by the IC technology and Electronics group at Twente University of Technology. The damage and anneal behaviour of 1 MeV boron implantations to a dose of 10 13 /cm 2 have been investigated as a function of anneal temperature by sheet resistance, Hall and noise measurements. (Auth.)

  5. Investigation of the silicon ion density during molecular beam epitaxy growth

    CERN Document Server

    Eifler, G; Ashurov, K; Morozov, S

    2002-01-01

    Ions impinging on a surface during molecular beam epitaxy influence the growth and the properties of the growing layer, for example, suppression of dopant segregation and the generation of crystal defects. The silicon electron gun in the molecular beam epitaxy (MBE) equipment is used as a source for silicon ions. To use the effect of ion bombardment the mechanism of generation and distribution of ions was investigated. A monitoring system was developed and attached at the substrate position in the MBE growth chamber to measure the ion and electron densities towards the substrate. A negative voltage was applied to the substrate to modify the ion energy and density. Furthermore the current caused by charge carriers impinging on the substrate was measured and compared with the results of the monitoring system. The electron and ion densities were measured by varying the emission current of the e-gun achieving silicon growth rates between 0.07 and 0.45 nm/s and by changing the voltage applied to the substrate betw...

  6. Destructive role of hot ions in the formation of electrostatic density humps and dips in dusty plasmas

    International Nuclear Information System (INIS)

    Mahmood, S.; Saleem, H.

    2003-01-01

    It is shown that the ion thermal energy is destructive for the ion acoustic solitons in the presence of dust, and it decreases the value of Mach number for the formation of solitary structures. The regions of ion density humps and dips are produced simultaneously, corresponding to positive and negative values of the electrostatic potential. The nonlinear electron density also behaves in a similar fashion as that of ions. However, the dust density increases in the regions where the ion and electron densities are depleted and vice versa

  7. High energy density redox flow device

    Science.gov (United States)

    Chiang, Yet-Ming; Carter, William Craig; Duduta, Mihai; Limthongkul, Pimpa

    2014-05-13

    Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

  8. Perspectives on High-Energy-Density Physics

    Science.gov (United States)

    Drake, R. Paul

    2008-11-01

    Much of 21st century plasma physics will involve work to produce, understand, control, and exploit very non-traditional plasmas. High-energy density (HED) plasmas are often examples, variously involving strong Coulomb interactions and few particles per Debeye sphere, dominant radiation effects, strongly relativistic effects, or strongly quantum-mechanical behavior. Indeed, these and other modern plasma systems often fall outside the early standard theoretical definitions of ``plasma''. This presentation will focus on two types of HED plasmas that exhibit non-traditional behavior. Our first example will be the plasmas produced by extremely strong shock waves. Shock waves are present across the entire realm of plasma densities, often in space or astrophysical contexts. HED shock waves (at pressures > 1 Mbar) enable studies in many areas, from equations of state to hydrodynamics to radiation hydrodynamics. We will specifically consider strongly radiative shocks, in which the radiative energy fluxes are comparable to the mechanical energy fluxes that drive the shocks. Modern HED facilities can produce such shocks, which are also present in dense, energetic, astrophysical systems such as supernovae. These shocks are also excellent targets for advanced simulations due to their range of spatial scales and complex radiation transport. Our second example will be relativistic plasmas. In general, these vary from plasmas containing relativistic particle beams, produced for some decades in the laboratory, to the relativistic thermal plasmas present for example in pulsar winds. Laboratory HED relativistic plasmas to date have been those produced by laser beams of irradiance ˜ 10^18 to 10^22 W/cm^2 or by accelerator-produced HED electron beams. These have applications ranging from generation of intense x-rays to production of proton beams for radiation therapy to acceleration of electrons. Here we will focus on electron acceleration, a spectacular recent success and a rare

  9. Features of laser spectroscopy and diagnostics of plasma ions in high magnetic fields

    International Nuclear Information System (INIS)

    Semerok, A F; Fomichev, S V

    2003-01-01

    Laser induced fluorescence and laser absorption spectroscopies of plasma ions in high magnetic fields have been investigated. Both the high degree of Zeeman splitting of the resonant transitions and the ion rotational movement drastically change the properties of the resonance interaction of the continuous wave laser radiation with ions in highly magnetized plasma. Numerical solution of the density matrix equation for a dissipative two-level system with time-dependent detuning from resonance was used to analyse this interaction. A theoretical simulation was performed and compared with the experimental results obtained from the laser spectroscopy diagnostics of barium plasma ions in high magnetic fields in the several tesla range

  10. Real-time control of ion density and ion energy in chlorine inductively coupled plasma etch processing

    International Nuclear Information System (INIS)

    Chang, C.-H.; Leou, K.-C.; Lin Chaung; Lin, T.-L.; Tseng, C.-W.; Tsai, C.-H.

    2003-01-01

    In this study, we have experimentally demonstrated the real-time closed-loop control of both ion density and ion energy in a chlorine inductively coupled plasma etcher. To measure positive ion density, the trace rare gases-optical emission spectroscopy is used to measure the chlorine positive ion density. An rf voltage probe is adopted to measure the root-mean-square rf voltage on the electrostatic chuck which is linearly dependent on sheath voltage. One actuator is a 13.56 MHz rf generator to drive the inductive coil seated on a ceramic window. The second actuator is also a 13.56 MHz rf generator to power the electrostatic chuck. The closed-loop controller is designed to compensate for process drift, process disturbance, and pilot wafer effect and to minimize steady-state error of plasma parameters. This controller has been used to control the etch process of unpatterned polysilicon. The experimental results showed that the closed-loop control had a better repeatability of plasma parameters compared with open-loop control. The closed-loop control can eliminate the process disturbance resulting from reflected power. In addition, experimental results also demonstrated that closed-loop control has a better reproducibility in etch rate as compared with open-loop control

  11. Ultrahigh-Energy Density Lithium-Ion Cable Battery Based on the Carbon-Nanotube Woven Macrofilms.

    Science.gov (United States)

    Wu, Ziping; Liu, Kaixi; Lv, Chao; Zhong, Shengwen; Wang, Qinghui; Liu, Ting; Liu, Xianbin; Yin, Yanhong; Hu, Yingyan; Wei, Di; Liu, Zhongfan

    2018-05-01

    Moore's law predicts the performance of integrated circuit doubles every two years, lasting for more than five decades. However, the improvements of the performance of energy density in batteries lag far behind that. In addition, the poor flexibility, insufficient-energy density, and complexity of incorporation into wearable electronics remain considerable challenges for current battery technology. Herein, a lithium-ion cable battery is invented, which is insensitive to deformation due to its use of carbon nanotube (CNT) woven macrofilms as the charge collectors. An ultrahigh-tap density of 10 mg cm -2 of the electrodes can be obtained, which leads to an extremely high-energy density of 215 mWh cm -3 . The value is approximately seven times than that of the highest performance reported previously. In addition, the battery displays very stable rate performance and lower internal resistance than conventional lithium-ion batteries using metal charge collectors. Moreover, it demonstrates excellent convenience for connecting electronics as a new strategy is applied, in which both electrodes can be integrated into one end by a CNT macrorope. Such an ultrahigh-energy density lithium-ion cable battery provides a feasible way to power wearable electronics with commercial viability. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Ultrathin Coaxial Fiber Supercapacitors Achieving High Energy and Power Densities.

    Science.gov (United States)

    Shen, Caiwei; Xie, Yingxi; Sanghadasa, Mohan; Tang, Yong; Lu, Longsheng; Lin, Liwei

    2017-11-15

    Fiber-based supercapacitors have attracted significant interests because of their potential applications in wearable electronics. Although much progress has been made in recent years, the energy and power densities, mechanical strength, and flexibility of such devices are still in need of improvement for practical applications. Here, we demonstrate an ultrathin microcoaxial fiber supercapacitor (μCFSC) with high energy and power densities (2.7 mW h/cm 3 and 13 W/cm 3 ), as well as excellent mechanical properties. The prototype with the smallest reported overall diameter (∼13 μm) is fabricated by successive coating of functional layers onto a single micro-carbon-fiber via a scalable process. Combining the simulation results via the electrochemical model, we attribute the high performance to the well-controlled thin coatings that make full use of the electrode materials and minimize the ion transport path between electrodes. Moreover, the μCFSC features high bending flexibility and large tensile strength (more than 1 GPa), which make it promising as a building block for various flexible energy storage applications.

  13. Modelling high density phenomena in hydrogen fibre Z-pinches

    International Nuclear Information System (INIS)

    Chittenden, J.P.

    1990-09-01

    The application of hydrogen fibre Z-pinches to the study of the radiative collapse phenomenon is studied computationally. Two areas of difficulty, the formation of a fully ionized pinch from a cryogenic fibre and the processes leading to collapse termination, are addressed in detail. A zero-D model based on the energy equation highlights the importance of particle end losses and changes in the Coulomb logarithm upon collapse initiation and termination. A 1-D Lagrangian resistive MHD code shows the importance of the changing radial profile shapes, particularly in delaying collapse termination. A 1-D, three fluid MHD code is developed to model the ionization of the fibre by thermal conduction from a high temperature surface corona to the cold core. Rate equations for collisional ionization, 3-body recombination and equilibration are solved in tandem with fluid equations for the electrons, ions and neutrals. Continuum lowering is found to assist ionization at the corona-core interface. The high density plasma phenomena responsible for radiative collapse termination are identified as the self-trapping of radiation and free electron degeneracy. A radiation transport model and computational analogues for the effects of degeneracy upon the equation of state, transport coefficients and opacity are implemented in the 1-D, single fluid model. As opacity increases the emergent spectrum is observed to become increasingly Planckian and a fall off in radiative cooling at small radii and low frequencies occurs giving rise to collapse termination. Electron degeneracy terminates radiative collapse by supplementing the radial pressure gradient until the electromagnetic pinch force is balanced. Collapse termination is found to be a hybrid process of opacity and degeneracy effects across a wide range of line densities with opacity dominant at large line densities but with electron degeneracy becoming increasingly important at lower line densities. (author)

  14. Probing the vacuum with highly charged ions

    International Nuclear Information System (INIS)

    Bottcher, C.; Strayer, M.R.

    1987-01-01

    The physics of the Fermion vacuum is briefly described, and applied to pair production in heavy ion collisions. We consider in turn low energies (<50 MeV/nucleon), intermediate energies (<5 GeV/nucleon), and ultrahigh energies such as would be produced in a ring collider. At high energies, interesting questions of Lorentz and gauge invariance arise. Finally, some applications to the structure of high Z atoms are examined. 14 refs., 11 figs

  15. Highly featured amorphous silicon nanorod arrays for high-performance lithium-ion batteries

    International Nuclear Information System (INIS)

    Soleimani-Amiri, Samaneh; Safiabadi Tali, Seied Ali; Azimi, Soheil; Sanaee, Zeinab; Mohajerzadeh, Shamsoddin

    2014-01-01

    High aspect-ratio vertical structures of amorphous silicon have been realized using hydrogen-assisted low-density plasma reactive ion etching. Amorphous silicon layers with the thicknesses ranging from 0.5 to 10 μm were deposited using radio frequency plasma enhanced chemical vapor deposition technique. Standard photolithography and nanosphere colloidal lithography were employed to realize ultra-small features of the amorphous silicon. The performance of the patterned amorphous silicon structures as a lithium-ion battery electrode was investigated using galvanostatic charge-discharge tests. The patterned structures showed a superior Li-ion battery performance compared to planar amorphous silicon. Such structures are suitable for high current Li-ion battery applications such as electric vehicles

  16. Highly featured amorphous silicon nanorod arrays for high-performance lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Soleimani-Amiri, Samaneh; Safiabadi Tali, Seied Ali; Azimi, Soheil; Sanaee, Zeinab; Mohajerzadeh, Shamsoddin, E-mail: mohajer@ut.ac.ir [Thin Film and Nanoelectronics Lab, Nanoelectronics Center of Excellence, School of Electrical and Computer Engineering, University of Tehran, Tehran 143957131 (Iran, Islamic Republic of)

    2014-11-10

    High aspect-ratio vertical structures of amorphous silicon have been realized using hydrogen-assisted low-density plasma reactive ion etching. Amorphous silicon layers with the thicknesses ranging from 0.5 to 10 μm were deposited using radio frequency plasma enhanced chemical vapor deposition technique. Standard photolithography and nanosphere colloidal lithography were employed to realize ultra-small features of the amorphous silicon. The performance of the patterned amorphous silicon structures as a lithium-ion battery electrode was investigated using galvanostatic charge-discharge tests. The patterned structures showed a superior Li-ion battery performance compared to planar amorphous silicon. Such structures are suitable for high current Li-ion battery applications such as electric vehicles.

  17. Effect of ion orbit loss on the structure in the H-mode tokamak edge pedestal profiles of rotation velocity, radial electric field, density, and temperature

    International Nuclear Information System (INIS)

    Stacey, Weston M.

    2013-01-01

    An investigation of the effect of ion orbit loss of thermal ions and the compensating return ion current directly on the radial ion flux flowing in the plasma, and thereby indirectly on the toroidal and poloidal rotation velocity profiles, the radial electric field, density, and temperature profiles, and the interpretation of diffusive and non-diffusive transport coefficients in the plasma edge, is described. Illustrative calculations for a high-confinement H-mode DIII-D [J. Luxon, Nucl. Fusion 42, 614 (2002)] plasma are presented and compared with experimental results. Taking into account, ion orbit loss of thermal ions and the compensating return ion current is found to have a significant effect on the structure of the radial profiles of these quantities in the edge plasma, indicating the necessity of taking ion orbit loss effects into account in interpreting or predicting these quantities

  18. Workshop on High Power ICH Antenna Designs for High Density Tokamaks

    Science.gov (United States)

    Aamodt, R. E.

    1990-02-01

    A workshop in high power ICH antenna designs for high density tokamaks was held to: (1) review the data base relevant to the high power heating of high density tokamaks; (2) identify the important issues which need to be addressed in order to ensure the success of the ICRF programs on CIT and Alcator C-MOD; and (3) recommend approaches for resolving the issues in a timely realistic manner. Some specific performance goals for the antenna system define a successful design effort. Simply stated these goals are: couple the specified power per antenna into the desired ion species; produce no more than an acceptable level of RF auxiliary power induced impurities; and have a mechanical structure which safely survives the thermal, mechanical and radiation stresses in the relevant environment. These goals are intimately coupled and difficult tradeoffs between scientific and engineering constraints have to be made.

  19. Workshop on high power ICH antenna designs for high density tokamaks

    International Nuclear Information System (INIS)

    Aamodt, R.E.

    1990-01-01

    A workshop in high power ICH antenna designs for high density tokamaks was held in Boulder, Colorado on January 31 through February 2, 1990. The purposes of the workshop were to: (1) review the data base relevant to the high power heating of high density tokamaks; (2) identify the important issues which need to be addressed in order to ensure the success of the ICRF programs on CIT and Alcator C-MOD; and (3) recommend approaches for resolving the issues in a timely realistic manner. Some specific performance goals for the antenna system define a successful design effort. Simply stated these goals are: couple the specified power per antenna into the desired ion species; produce no more than an acceptable level of rf auxiliary power induced impurities; and have a mechanical structure which safely survives the thermal, mechanical and radiation stresses in the relevant environment. These goals are intimately coupled and difficult tradeoffs between scientific and engineering constraints have to be made

  20. Ion acceleration in electrostatic collisionless shock: on the optimal density profile for quasi-monoenergetic beams

    Science.gov (United States)

    Boella, E.; Fiúza, F.; Stockem Novo, A.; Fonseca, R.; Silva, L. O.

    2018-03-01

    A numerical study on ion acceleration in electrostatic shock waves is presented, with the aim of determining the best plasma configuration to achieve quasi-monoenergetic ion beams in laser-driven systems. It was recently shown that tailored near-critical density plasmas characterized by a long-scale decreasing rear density profile lead to beams with low energy spread (Fiúza et al 2012 Phys. Rev. Lett. 109 215001). In this work, a detailed parameter scan investigating different plasma scale lengths is carried out. As result, the optimal plasma spatial scale length that allows for minimizing the energy spread while ensuring a significant reflection of ions by the shock is identified. Furthermore, a new configuration where the required profile has been obtained by coupling micro layers of different densities is proposed. Results show that this new engineered approach is a valid alternative, guaranteeing a low energy spread with a higher level of controllability.

  1. Forbidden lines of highly ionized ions for localized plasma diagnostics

    International Nuclear Information System (INIS)

    Hinnov, E.; Fonck, R.; Suckewer, S.

    1980-06-01

    Numerous optically forbidden lines resulting from magnetic dipole transitions in low-lying electron configurations of highly ionized Fe, Ti and Cr atoms have been identified in PLT and PDX tokamak discharges, and applied for localized diagnostics in the high-temperature (0.5 to 3.0 keV) interior of these plasmas. The measurements include determination of local ion densities and their variation in time, and of ion motions (ion temperature, plasma rotations) through Doppler effect of the lines. These forbidden lines are particularly appropriate for such measurements because under typical tokamak conditions their emissivities are quite high (10 11 to 10 14 photons/cm 3 -sec), and their relatively long wavelengths allow the use of intricate optical techniques and instrumentation. The spatial location of the emissivity is directly measurable, and tends to occur near radii where the ionization potential of the ion in question is equal to the local electron temperature. In future larger and presumably higher-temperature tokamaks analogous measurements with somewhat heavier atoms, particularly krypton, and perhaps zirconium appear both feasible and desirable

  2. Discovery of hydrodynamic behavior in high energy heavy ion collisions

    International Nuclear Information System (INIS)

    Hamagaki, Hideki

    2010-01-01

    The objective of high energy heavy ion collision experiments is creating high temperature and high density states to investigate hadron matter properties in such extreme conditions. Since the start of heavy ion collision experiments with BEVALAC, knowledge of the space-time evolution of collision has become indispensable for understanding the hadronic matter properties. This problem is reviewed here from the hydrodynamics view point. Although its importance has been generally recognized since the time of BEVALAC, the hydrodynamic description has not been successful because the hydrodynamic model assuming non-viscous or small fluid had not been considered to be enough to properly describe the space-time evolution of hadron-hadron collisions until the RHIC experiments. Items of the following titles are picked up and reviewed here: Development of heavy ion accelerations; Space-time evolution of hadron collision process and hydrodynamic model; Chemical freezing and kinematical freezing, including transverse momentum spectra at proton-proton collisions and particle spectra in heavy ion collisions; Elliptical azimuthal angle anisotropy; Discovery of hydrodynamic flow at BEVALAC; Problems of incident beam dependence of v2; Elliptic azimuthal angle anisotropy at RHIC; What is it that carries the elliptic anisotropy? Discussion of attainment of thermodynamical equilibrium state at RHIC; and finally investigations of fluid properties other than azimuthal anisotropy, such as, Fluid properties probed by heavy quarks and Observing QCD fluid responses. (S. Funahashi)

  3. Diagnostic Spectrometers for High Energy Density X-Ray Sources

    International Nuclear Information System (INIS)

    Hudson, L. T.; Henins, A.; Seely, J. F.; Holland, G. E.

    2007-01-01

    A new generation of advanced laser, accelerator, and plasma confinement devices are emerging that are producing extreme states of light and matter that are unprecedented for laboratory study. Examples of such sources that will produce laboratory x-ray emissions with unprecedented characteristics include megajoule-class and ultrafast, ultraintense petawatt laser-produced plasmas; tabletop high-harmonic-generation x-ray sources; high-brightness zeta-pinch and magnetically confined plasma sources; and coherent x-ray free electron lasers and compact inverse-Compton x-ray sources. Characterizing the spectra, time structure, and intensity of x rays emitted by these and other novel sources is critical to assessing system performance and progress as well as pursuing the new and unpredictable physical interactions of interest to basic and applied high-energy-density (HED) science. As these technologies mature, increased emphasis will need to be placed on advanced diagnostic instrumentation and metrology, standard reference data, absolute calibrations and traceability of results.We are actively designing, fabricating, and fielding wavelength-calibrated x-ray spectrometers that have been employed to register spectra from a variety of exotic x-ray sources (electron beam ion trap, electron cyclotron resonance ion source, terawatt pulsed-power-driven accelerator, laser-produced plasmas). These instruments employ a variety of curved-crystal optics, detector technologies, and data acquisition strategies. In anticipation of the trends mentioned above, this paper will focus primarily on optical designs that can accommodate the high background signals produced in HED experiments while also registering their high-energy spectral emissions. In particular, we review the results of recent laboratory testing that explores off-Rowland circle imaging in an effort to reclaim the instrumental resolving power that is increasingly elusive at higher energies when using wavelength

  4. Highly efficient red electrophosphorescent devices at high current densities

    International Nuclear Information System (INIS)

    Wu Youzhi; Zhu Wenqing; Zheng Xinyou; Sun, Runguang; Jiang Xueyin; Zhang Zhilin; Xu Shaohong

    2007-01-01

    Efficiency decrease at high current densities in red electrophosphorescent devices is drastically restrained compared with that from conventional electrophosphorescent devices by using bis(2-methyl-8-quinolinato)4-phenylphenolate aluminum (BAlq) as a hole and exciton blocker. Ir complex, bis(2-(2'-benzo[4,5-α]thienyl) pyridinato-N,C 3' ) iridium (acetyl-acetonate) is used as an emitter, maximum external quantum efficiency (QE) of 7.0% and luminance of 10000cd/m 2 are obtained. The QE is still as high as 4.1% at higher current density J=100mA/cm 2 . CIE-1931 co-ordinates are 0.672, 0.321. A carrier trapping mechanism is revealed to dominate in the process of electroluminescence

  5. High-density oxidized porous silicon

    International Nuclear Information System (INIS)

    Gharbi, Ahmed; Souifi, Abdelkader; Remaki, Boudjemaa; Halimaoui, Aomar; Bensahel, Daniel

    2012-01-01

    We have studied oxidized porous silicon (OPS) properties using Fourier transform infraRed (FTIR) spectroscopy and capacitance–voltage C–V measurements. We report the first experimental determination of the optimum porosity allowing the elaboration of high-density OPS insulators. This is an important contribution to the research of thick integrated electrical insulators on porous silicon based on an optimized process ensuring dielectric quality (complete oxidation) and mechanical and chemical reliability (no residual pores or silicon crystallites). Through the measurement of the refractive indexes of the porous silicon (PS) layer before and after oxidation, one can determine the structural composition of the OPS material in silicon, air and silica. We have experimentally demonstrated that a porosity approaching 56% of the as-prepared PS layer is required to ensure a complete oxidation of PS without residual silicon crystallites and with minimum porosity. The effective dielectric constant values of OPS materials determined from capacitance–voltage C–V measurements are discussed and compared to FTIR results predictions. (paper)

  6. Advanced Electrodes for High Power Li-ion Batteries

    Directory of Open Access Journals (Sweden)

    Christian M. Julien

    2013-03-01

    Full Text Available While little success has been obtained over the past few years in attempts to increase the capacity of Li-ion batteries, significant improvement in the power density has been achieved, opening the route to new applications, from hybrid electric vehicles to high-power electronics and regulation of the intermittency problem of electric energy supply on smart grids. This success has been achieved not only by decreasing the size of the active particles of the electrodes to few tens of nanometers, but also by surface modification and the synthesis of new multi-composite particles. It is the aim of this work to review the different approaches that have been successful to obtain Li-ion batteries with improved high-rate performance and to discuss how these results prefigure further improvement in the near future.

  7. Fundamental properties of high-quality carbon nanofoam: from low to high density

    Directory of Open Access Journals (Sweden)

    Natalie Frese

    2016-12-01

    Full Text Available Highly uniform samples of carbon nanofoam from hydrothermal sucrose carbonization were studied by helium ion microscopy (HIM, X-ray photoelectron spectroscopy (XPS, and Raman spectroscopy. Foams with different densities were produced by changing the process temperature in the autoclave reactor. This work illustrates how the geometrical structure, electron core levels, and the vibrational signatures change when the density of the foams is varied. We find that the low-density foams have very uniform structure consisting of micropearls with ≈2–3 μm average diameter. Higher density foams contain larger-sized micropearls (≈6–9 μm diameter which often coalesced to form nonspherical μm-sized units. Both, low- and high-density foams are comprised of predominantly sp2-type carbon. The higher density foams, however, show an advanced graphitization degree and a stronger sp3-type electronic contribution, related to the inclusion of sp3 connections in their surface network.

  8. Ion production and bipolar fluxes in a high-current plasma-filled diode

    International Nuclear Information System (INIS)

    Ivanenkov, G.V.

    1982-01-01

    The model and the evolution of behaviour of binary layers (BL) in expanding plasma of high current plasma-filled diode are described. The model estimates ion current and the laws of plasma expansion at the stage of BL intensive growth. The density range (10 12 -10 15 cm -3 ) is determined in which diode impedance growth takes place in connection with BL appearance. The density of ion current at the outlet of diode is 10 A/cm 2

  9. Mesospheric H2O and H2O2 densities inferred from in situ positive ion composition measurement

    Science.gov (United States)

    Kopp, E.

    1984-01-01

    A model for production and loss of oxonium ions in the high-latitude D-region is developed, based on the observed excess of 34(+) which has been interpreted as H2O2(+). The loss mechanism suggested in the study is the attachment of N2 and/or CO2 in three-body reactions. Furthermore, mesospheric water vapor and H2O2 densities are inferred from measurements of four high-latitude ion compositions, based on the oxonium model. Mixing ratios of hydrogen peroxide of up to two orders of magnitude higher than previous values were obtained. A number of reactions, reaction constants, and a block diagram of the oxonium ion chemistry in the D-region are given.

  10. Density measurements of small amounts of high-density solids by a floatation method

    International Nuclear Information System (INIS)

    Akabori, Mitsuo; Shiba, Koreyuki

    1984-09-01

    A floatation method for determining the density of small amounts of high-density solids is described. The use of a float combined with an appropriate floatation liquid allows us to measure the density of high-density substances in small amounts. Using the sample of 0.1 g in weight, the floatation liquid of 3.0 g cm -3 in density and the float of 1.5 g cm -3 in apparent density, the sample densities of 5, 10 and 20 g cm -3 are determined to an accuracy better than +-0.002, +-0.01 and +-0.05 g cm -3 , respectively that correspond to about +-1 x 10 -5 cm 3 in volume. By means of appropriate degassing treatments, the densities of (Th,U)O 2 pellets of --0.1 g in weight and --9.55 g cm -3 in density were determined with an accuracy better than +-0.05 %. (author)

  11. New experimental initiatives using very highly charged ions from an 'electron beam ion trap'

    International Nuclear Information System (INIS)

    Schneider, D.

    1996-01-01

    A short review of the experimental program in highly-charged heavy ion physics conducted at the Lawrence Livermore National Laboratory Electron Beam Ion Trap (EBIT) facility is presented. The heavy-ion research, involving ions up to fully stripped U 92+ , includes precision x-ray spectroscopy and lifetime studies, electron impact ionization and excitation cross section measurements. The investigations of ion-surface interactions following the impact of high-Z highly charged ions on surfaces are aimed to study the neutralization dynamics effecting the ion and the response of the surface as well. (author)

  12. Ion-sound emission by Langmuir soliton reflected at density barrier

    International Nuclear Information System (INIS)

    El-Ashry, M.Y.

    1989-07-01

    The emission of ion-sound waves by an accelerated Langmuir soliton is studied. The acceleration of the soliton is due to an inhomogeneous density barrier. On the assumption that the kinetic energy of the Langmuir soliton is smaller than the potential energy created by the barrier. The basic equations describing the dynamic behaviour of the soliton and the emission of the ion-sound waves are formulated. The qualitative spatial distributions of the perturbed concentration in the ion-sound waves are analyzed at different characteristic points of the soliton. The energy lost by the soliton, as a result of the emission, is estimated. (author). 6 refs, 4 figs

  13. A thermodynamic perturbation theory for the surface tension and ion density profile of a liquid metal

    International Nuclear Information System (INIS)

    Evans, R.; Kumaravadivel, R.

    1976-01-01

    A simple scheme for determining the ion density profile and the surface tension of a liquid metal is described. Assuming that the interaction between metallic pseudo-ions is of the form introduced by Evans, an approximate expression for the excess free energy of the system is derived using the thermodynamic perturbation theory of Weeks, Chandler and Anderson. This excess free energy is then minimized with respect to a parameter which specifies the ion density profile, and the surface tension is given directly. From a consideration of the dependence of the interionic forces on the electron density it is predicted that the ions should take up a very steep density profile at the liquid metal surface. This behaviour is contrasted with that to be expected for rare-gas fluids in which the interatomic forces are density-independent. The values of the surface tension calculated for liquid Na, K and Al from a simplified version of the theory are in reasonable agreement with experiment. (author)

  14. Ion filter for high temperature cleaning

    International Nuclear Information System (INIS)

    Kutomi, Yasuhiro; Nakamori, Masaharu.

    1994-01-01

    A porous ceramic pipe mainly comprising alumina is used as a base pipe, and then crud and radioactive ion adsorbing materials in high temperature and high pressure water mainly comprising a FeTiO 3 compound are flame-coated on the outer surface thereof to a film thickness of about 100 to 300μ m as an aimed value by an acetylene flame-coating method. The flame-coated FeTiO 3 layer is also porous, so that high temperature and high pressure water to be cleaned can pass through from the inside to the outside of the pipe. Cruds can be removed and radioactive ions can be adsorbed during passage. Since all the operations can be conducted at high temperature and high pressure state, cooling is no more necessary for the high temperature and high pressure water to be cleaned, heat efficiency of the plant can be improved and a cooling facility can be saved. Further, since the flame-coating of FeTiO 3 to the porous ceramic pipe can be conducted extremely easily compared with production of a sintering product, cost for the production of filter elements can be saved remarkably. (T.M.)

  15. Role of ion magnetization in formation of radial density profile in magnetically expanding plasma produced by helicon antenna

    Science.gov (United States)

    Yadav, Sonu; Ghosh, Soumen; Bose, Sayak; Barada, Kshitish K.; Pal, Rabindranath; Chattopadhyay, Prabal K.

    2018-04-01

    Experimentally, the density profile in the magnetic nozzle of a helicon antenna based plasma device is seen to be modified from being centrally peaked to that of hollow nature as the external magnetic field is increased. It occurs above a characteristic field value when the ions become magnetized in the expansion chamber. The density profile in the source chamber behind the nozzle, however, remains peaked on-axis irrespective of the magnetic field. The electron temperature there is observed to be hollow and this nature is carried to the expansion chamber along the field line. In the electron energy distribution near the off axis peak location, a high energy tail exists. Rotation of these tail electrons in the azimuthal direction due to the gradient-B drift in the expansion chamber leads to an additional off-axis ionization and forms the hollow density profile. It seems that if the ions are not magnetized, then the off-axially produced additional plasma is not confined and the density profile retains the on-axis peak nature. The present experiment successfully demonstrates how the knowledge of the ion magnetization together with tail electrons significantly contributes to the design of an efficient helicon plasma based thruster.

  16. Potential formation and confinement in high density plasma on the GAMMA 10 tandem mirror

    International Nuclear Information System (INIS)

    Yatsu, K.

    2002-01-01

    After the attainment of doubling of the density due to the potential confinement, GAMMA 10 experiments have been directed to realization of a high density plasma and also to study dependence of the confining potential and confinement time on the plasma density. These problems are important to understand the physics of potential formation in tandem mirrors and also for the development of a tandem mirror reactor. We reported high density plasma production by using an ion cyclotron range of frequency heating at a high harmonic frequency in the last IAEA Conference. However, the diamagnetic signal of the high density plasma decreased when electron cyclotron resonance heating (ECRH) was applied due to some instabilities. Recently, the high density plasma production was much improved by adjusting the spacing of the conducting plates installed in the anchor transition regions, which enabled us to produce a high density plasma without degradation of the diamagnetic signal with ECRH and also to study the density dependence. In this paper we report production of a high density plasma and dependence of the confining potential and the confinement time on the density. (author)

  17. High Fidelity Ion Beam Simulation of High Dose Neutron Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Was, Gary; Wirth, Brian; Motta, Athur; Morgan, Dane; Kaoumi, Djamel; Hosemann, Peter; Odette, Robert

    2018-04-30

    Project Objective: The objective of this proposal is to demonstrate the capability to predict the evolution of microstructure and properties of structural materials in-reactor and at high doses, using ion irradiation as a surrogate for reactor irradiations. “Properties” includes both physical properties (irradiated microstructure) and the mechanical properties of the material. Demonstration of the capability to predict properties has two components. One is ion irradiation of a set of alloys to yield an irradiated microstructure and corresponding mechanical behavior that are substantially the same as results from neutron exposure in the appropriate reactor environment. Second is the capability to predict the irradiated microstructure and corresponding mechanical behavior on the basis of improved models, validated against both ion and reactor irradiations and verified against ion irradiations. Taken together, achievement of these objectives will yield an enhanced capability for simulating the behavior of materials in reactor irradiations

  18. High-current discharge channel contraction in high density gas

    International Nuclear Information System (INIS)

    Rutberg, Ph. G.; Bogomaz, A. A.; Pinchuk, M. E.; Budin, A. V.; Leks, A. G.; Pozubenkov, A. A.

    2011-01-01

    Research results for discharges at current amplitudes of 0.5-1.6 MA and current rise rate of ∼10 10 A/s are presented. The discharge is performed in the hydrogen environment at the initial pressure of 5-35 MPa. Initiation is implemented by a wire explosion. The time length of the first half-period of the discharge current is 70-150 μs. Under such conditions, discharge channel contraction is observed; the contraction is followed by soft x-ray radiation. The phenomena are discussed, which are determined by high density of the gas surrounding the discharge channel. These phenomena are increase of the current critical value, where the channel contraction begins and growth of temperature in the axis region of the channel, where the initial density of the gas increases.

  19. Highly porous carbon with large electrochemical ion absorption capability for high-performance supercapacitors and ion capacitors

    Science.gov (United States)

    Wang, Shijie; Wang, Rutao; Zhang, Yabin; Zhang, Li

    2017-11-01

    Carbon-based supercapacitors have attracted extensive attention as the complement to batteries, owing to their durable lifespan and superiority in high-power-demand fields. However, their widespread use is limited by the low energy storage density; thus, a high-surface-area porous carbon is urgently needed. Herein, a highly porous carbon with a Brunauer-Emmett-Teller specific surface area up to 3643 m2 g-1 has been synthesized by chemical activation of papayas for the first time. This sp2-bonded porous carbon has a continuous three-dimensional network of highly curved, atom-thick walls that form narrow mesopores of 2 ˜ 5 nm in width, which can be systematically tailored with varied activation levels. Two-electrode symmetric supercapacitors constructed by this porous carbon achieve energy density of 8.1 Wh kg-1 in aqueous electrolyte and 65.5 Wh kg-1 in ionic-liquid electrolyte. Furthermore, half-cells (versus Li or Na metal) using this porous carbon as ion sorption cathodes yield high specific capacity, e.g., 51.0 and 39.3 mAh g-1 in Li+ and Na+ based organic electrolyte. These results underline the possibility of obtaining the porous carbon for high-performance carbon-based supercapacitors and ion capacitors in a readily scalable and economical way.

  20. Highly porous carbon with large electrochemical ion absorption capability for high-performance supercapacitors and ion capacitors.

    Science.gov (United States)

    Wang, Shijie; Wang, Rutao; Zhang, Yabin; Zhang, Li

    2017-11-03

    Carbon-based supercapacitors have attracted extensive attention as the complement to batteries, owing to their durable lifespan and superiority in high-power-demand fields. However, their widespread use is limited by the low energy storage density; thus, a high-surface-area porous carbon is urgently needed. Herein, a highly porous carbon with a Brunauer-Emmett-Teller specific surface area up to 3643 m 2 g -1 has been synthesized by chemical activation of papayas for the first time. This sp 2 -bonded porous carbon has a continuous three-dimensional network of highly curved, atom-thick walls that form narrow mesopores of 2 ∼ 5 nm in width, which can be systematically tailored with varied activation levels. Two-electrode symmetric supercapacitors constructed by this porous carbon achieve energy density of 8.1 Wh kg -1 in aqueous electrolyte and 65.5 Wh kg -1 in ionic-liquid electrolyte. Furthermore, half-cells (versus Li or Na metal) using this porous carbon as ion sorption cathodes yield high specific capacity, e.g., 51.0 and 39.3 mAh g -1 in Li + and Na + based organic electrolyte. These results underline the possibility of obtaining the porous carbon for high-performance carbon-based supercapacitors and ion capacitors in a readily scalable and economical way.

  1. High temperature electron beam ion source for the production of single charge ions of most elements of the Periodic Table

    CERN Document Server

    Panteleev, V N; Barzakh, A E; Fedorov, D V; Ivanov, V S; Moroz, F V; Orlov, S Y; Seliverstov, D M; Stroe, L; Tecchio, L B; Volkov, Y M

    2003-01-01

    A new type of a high temperature electron beam ion source (HTEBIS) with a working temperature up to 2500 deg. C was developed for production of single charge ions of practically all elements. Off-line tests and on-line experiments making use of the developed ion source coupled with uranium carbide targets of different density, have been carried out. The ionization efficiency measured for stable atoms of many elements varied in the interval of 1-6%. Using the HTEBIS, the yields and on-line production efficiency of neutron rich isotopes of Mn, Fe, Co, Cu, Rh, Pd, Ag, Cd, In, Sn and isotopes of heavy elements Pb, Bi, Po and some others have been determined. The revealed confinement effect of the ions produced in the narrow electron beam inside a hot ion source cavity has been discussed.

  2. Propagation of sound wave in high density deuterium at high temperatures

    International Nuclear Information System (INIS)

    Inoue, Kazuko; Ariyasu, Tomio

    1986-01-01

    The velocity and the attenuation constant of sound wave have been calculated for high density (10 24 ∼ 10 27 /cm 3 ) deuterium at high temperatures (10 -1 ∼ 10 4 eV). This calculation was made to understand the fuel properties in inertial confinement fusion and to obtain the basic data for pellet design. The isentropic sound wave which propagates in deuterium in plasma state at temperature T i = T e , is dealt with. The velocity is derived using the modulus of bulk elasticity of the whole system and the modulus of shear elasticity due to ion-ion interaction. For the calculation of attenuation constant, the bulk and shear viscosity due to ion-ion interaction, the shear viscosity of free electron gas, and the thermal conductivity due to free electrons are considered. The condition of frequency for the existence of such isentropic sound wave is discussed. The possibility of penetration into the fuel pellet in inertial confinement fusion is also discussed. The followings have been found: (1) The sound velocity is determined mainly from the bulk elasticity. The contribution of the shear elasticity is small. The velocity ranges from 2.8 x 10 6 to 1.5 x 10 8 cm/s in the above mentioned temperature and density regions. (2) The coefficient of attenuation constant with respect to ω 2 /2ρu 3 plotted versus temperature with the parameter of density shows a minimum. At temperatures below this minimum, the attenuation comes mainly from the bulk viscosity due to ion-ion interaction and the shear viscosity due to free electron gas. At temperatures above this minimum, the sound is attenuated mainly by the thermal conductivity due to electrons. (3) The condition for the existence of such adiabatic sound wave, is satisfied with the frequency less than 10 10 Hz. But, as for the pellet design, the wave length of sound with frequency less than 10 10 Hz is longer than the diameter of pellet when compressed highly. (author)

  3. Ion sources development at GANIL for radioactive beams and high charge state ions

    International Nuclear Information System (INIS)

    Leroy, R.; Barue, C.; Canet, C.; Dupuis, M.; Flambard, J.L.; Gaubert, G.; Gibouin, S.; Huguet, Y.; Jardin, P.; Lecesne, N.; Leherissier, P.; Lemagnen, F.; Pacquet, J.Y.; Pellemoine-Landre, F.; Rataud, J.P.; Saint-Laurent, M.G.; Villari, A.C.C.; Maunoury, L.

    2001-01-01

    The GANIL laboratory has in charge the production of ion beams for nuclear and non nuclear physics. This article reviews the last developments that are underway in the fields of radioactive ion beam production, increase of the metallic ion intensities and production of highly charges ion beams. (authors)

  4. Unconventional High Density Vertically Aligned Conducting Polymer

    Science.gov (United States)

    2014-08-21

    gravimetric values of an electrode. As shown in Table 1, there is a close correlation between the specific gravimetric performance in terms of the whole...to 10nm, exhibit nearly ideal capacitive behavior (so that the Coulombic efficiency shows only a slight decrease, and is overall very close to 100...PEDOT thickness while avoiding keyhole formation (i.e., PEDOT blocking the ion channels), is a viable route towards increasing electrode performance

  5. Gas Transport and Density Control in the HYLIFE Heavy-Ion Beam Lines

    International Nuclear Information System (INIS)

    Debonnel, Christophe S.; Welch, Dale R.; Rose, David V.; Lawrence, Simon S.Yu; Peterson, Per F.

    2003-01-01

    The effective propagation and focusing of heavy-ion beams in the final-focus magnet region of inertial fusion target chambers require controlling the background gas density and pressure in the beam tubes. Liquid vortexes will coat the inside of the tubes next to the beam ports and will help eliminate the need for mechanical shutters to mitigate the venting of target chamber background gas into the final-focus magnet region. Before the neutralizing region, the beam space charge is high, and ablation and target debris deposition in the final-focus magnet region may cause voltage breakdown. Previous studies focused on evaluating the amount of target chamber debris reaching the entrance of the beam ports. The TSUNAMI code has now been used to assess the density, temperature, and velocity of the vortex debris transported ∼3 m up the beam tubes and reaching the final-focus magnet region, assuming that the liquid vortexes are perfectly absorbing surfaces. To further mitigate debris deposition in the final-focus magnet region, and prevent voltage breakdown, a 'magnetic shutter' has been envisaged to divert the debris out of the final-focus region. This shutter will prevent the hot ablation debris from reaching the magnet region and, coupled to some ionizing scheme, will conveniently suppress early ingression of debris into the final-focus magnet region

  6. Dispersion- and Exchange-Corrected Density Functional Theory for Sodium Ion Hydration.

    Science.gov (United States)

    Soniat, Marielle; Rogers, David M; Rempe, Susan B

    2015-07-14

    A challenge in density functional theory is developing functionals that simultaneously describe intermolecular electron correlation and electron delocalization. Recent exchange-correlation functionals address those two issues by adding corrections important at long ranges: an atom-centered pairwise dispersion term to account for correlation and a modified long-range component of the electron exchange term to correct for delocalization. Here we investigate how those corrections influence the accuracy of binding free energy predictions for sodium-water clusters. We find that the dual-corrected ωB97X-D functional gives cluster binding energies closest to high-level ab initio methods (CCSD(T)). Binding energy decomposition shows that the ωB97X-D functional predicts the smallest ion-water (pairwise) interaction energy and larger multibody contributions for a four-water cluster than most other functionals - a trend consistent with CCSD(T) results. Also, ωB97X-D produces the smallest amounts of charge transfer and the least polarizable waters of the density functionals studied, which mimics the lower polarizability of CCSD. When compared with experimental binding free energies, however, the exchange-corrected CAM-B3LYP functional performs best (error <1 kcal/mol), possibly because of its parametrization to experimental formation enthalpies. For clusters containing more than four waters, "split-shell" coordination must be considered to obtain accurate free energies in comparison with experiment.

  7. Comparison of measured and modelled negative hydrogen ion densities at the ECR-discharge HOMER

    Energy Technology Data Exchange (ETDEWEB)

    Rauner, D.; Kurutz, U.; Fantz, U. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany); AG Experimentelle Plasmaphysik, Universität Augsburg, 86135 Augsburg (Germany)

    2015-04-08

    As the negative hydrogen ion density n{sub H{sup −}} is a key parameter for the investigation of negative ion sources, its diagnostic quantification is essential in source development and operation as well as for fundamental research. By utilizing the photodetachment process of negative ions, generally two different diagnostic methods can be applied: via laser photodetachment, the density of negative ions is measured locally, but only relatively to the electron density. To obtain absolute densities, the electron density has to be measured additionally, which induces further uncertainties. Via cavity ring-down spectroscopy (CRDS), the absolute density of H{sup −} is measured directly, however LOS-averaged over the plasma length. At the ECR-discharge HOMER, where H{sup −} is produced in the plasma volume, laser photodetachment is applied as the standard method to measure n{sub H{sup −}}. The additional application of CRDS provides the possibility to directly obtain absolute values of n{sub H{sup −}}, thereby successfully bench-marking the laser photodetachment system as both diagnostics are in good agreement. In the investigated pressure range from 0.3 to 3 Pa, the measured negative hydrogen ion density shows a maximum at 1 to 1.5 Pa and an approximately linear response to increasing input microwave powers from 200 up to 500 W. Additionally, the volume production of negative ions is 0-dimensionally modelled by balancing H{sup −} production and destruction processes. The modelled densities are adapted to the absolute measurements of n{sub H{sup −}} via CRDS, allowing to identify collisions of H{sup −} with hydrogen atoms (associative and non-associative detachment) to be the dominant loss process of H{sup −} in the plasma volume at HOMER. Furthermore, the characteristic peak of n{sub H{sup −}} observed at 1 to 1.5 Pa is identified to be caused by a comparable behaviour of the electron density with varying pressure, as n{sub e} determines

  8. Communication: Simple liquids' high-density viscosity

    Science.gov (United States)

    Costigliola, Lorenzo; Pedersen, Ulf R.; Heyes, David M.; Schrøder, Thomas B.; Dyre, Jeppe C.

    2018-02-01

    This paper argues that the viscosity of simple fluids at densities above that of the triple point is a specific function of temperature relative to the freezing temperature at the density in question. The proposed viscosity expression, which is arrived at in part by reference to the isomorph theory of systems with hidden scale invariance, describes computer simulations of the Lennard-Jones system as well as argon and methane experimental data and simulation results for an effective-pair-potential model of liquid sodium.

  9. Communication: Simple liquids' high-density viscosity.

    Science.gov (United States)

    Costigliola, Lorenzo; Pedersen, Ulf R; Heyes, David M; Schrøder, Thomas B; Dyre, Jeppe C

    2018-02-28

    This paper argues that the viscosity of simple fluids at densities above that of the triple point is a specific function of temperature relative to the freezing temperature at the density in question. The proposed viscosity expression, which is arrived at in part by reference to the isomorph theory of systems with hidden scale invariance, describes computer simulations of the Lennard-Jones system as well as argon and methane experimental data and simulation results for an effective-pair-potential model of liquid sodium.

  10. Growth limitation of Lemna minor due to high plant density

    NARCIS (Netherlands)

    Driever, S.M.; Nes, van E.H.; Roijackers, R.M.M.

    2005-01-01

    The effect of high population densities on the growth rate of Lemna minor (L.) was studied under laboratory conditions at 23°C in a medium with sufficient nutrients. At high population densities, we found a non-linear decreasing growth rate with increasing L. minor density. Above a L. minor biomass

  11. Imaginary time density-density correlations for two-dimensional electron gases at high density

    Energy Technology Data Exchange (ETDEWEB)

    Motta, M.; Galli, D. E. [Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Moroni, S. [IOM-CNR DEMOCRITOS National Simulation Center and SISSA, Via Bonomea 265, 34136 Trieste (Italy); Vitali, E. [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795 (United States)

    2015-10-28

    We evaluate imaginary time density-density correlation functions for two-dimensional homogeneous electron gases of up to 42 particles in the continuum using the phaseless auxiliary field quantum Monte Carlo method. We use periodic boundary conditions and up to 300 plane waves as basis set elements. We show that such methodology, once equipped with suitable numerical stabilization techniques necessary to deal with exponentials, products, and inversions of large matrices, gives access to the calculation of imaginary time correlation functions for medium-sized systems. We discuss the numerical stabilization techniques and the computational complexity of the methodology and we present the limitations related to the size of the systems on a quantitative basis. We perform the inverse Laplace transform of the obtained density-density correlation functions, assessing the ability of the phaseless auxiliary field quantum Monte Carlo method to evaluate dynamical properties of medium-sized homogeneous fermion systems.

  12. Characterization of low density carbon foams by x-ray computed tomography (CT) and ion microtomography (IMF)

    International Nuclear Information System (INIS)

    Moddeman, W.E.; Kramer, D.P.; Firsich, D.W.; Trainer, P.D.; Yancy, R.N.; Weirup, D.L.; Logan, C.M.; Pontau, A.E.; Antolak, A.J.; Morse, D.H.

    1990-01-01

    Two NDT techniques were used to characterize low-density, microcellular, carbon foams fabricated from a salt replica process. In this paper the two techniques are x-ray computed tomography (CT) and ion microtomography (IMT); data are presented on carbon foams that contain high-density regions. The data show that densities which differ by 3 ) materials. The data reveal that the carbon foams produced by this replica process have small density variations; the density being ∼30% greater at the outer edges than when compared to the interior of the foam. In addition, the density gradient is found to be rather sharp, that is the density drops-off rapidly from the outer edges to a uniform one in the interior of the foam. This edge build-up in carbon density was explained in terms of polymer concentrating on the foam exterior during drying which immediately followed a polymer infusion processing step. Supporting analytical data from other techniques show the foam material to be >88.8% carbon

  13. Review of high energy heavy ion experiments

    International Nuclear Information System (INIS)

    Miake, Yasuo

    2000-01-01

    It has been proposed that in high energy heavy ion collisions a physical conditions similar to the early stage of the Universe can be established in the laboratory. New phase of matter expected to be created is called the quark gluon plasma (QGP). Based on the motivation to create the QGP in the laboratory, heavy ion beams have been accelerated at AGS of Brookhaven National Laboratory and also at CERN-SPS. Several interesting features of the data have been reported, among which are: the suppression of J/ψ production in Pb+Pb collisions, the enhancement of low mass lepton pairs, and the collective behavior of hadron production. These features are reviewed under the key words of Deconfinement, Chiral Restoration and Collectivity in the lecture. (author)

  14. High energy ion microbeams and their applications

    International Nuclear Information System (INIS)

    Bakhru, H.; Nickles, E.; Haberl, A.; Morris, W.G.

    1992-01-01

    In recent years there has been rapid growth for the development of equipment for forming a focussed beam (0.5 - 2μm) with high energy ions. The State University of New York at Albany ion scanning microprobe has been used for several applications especially in the fields of materials and biological studies. Rutherford backscattering spectroscopy (RBS) and particle-induced x-ray emission (PIXE) analysis have been performed on microelectronic circuits with a spatial resolution of approximately 2 μm. Studies on films of superconductors (YBa CuO) will be presented. Applications of microbeams for the biological studies and analytical techniques will be presented. Current and future role of microbeams and their limitations will be discussed. (author)

  15. Electrode/Dielectric Strip For High-Energy-Density Capacitor

    Science.gov (United States)

    Yen, Shiao-Ping S.

    1994-01-01

    Improved unitary electrode/dielectric strip serves as winding in high-energy-density capacitor in pulsed power supply. Offers combination of qualities essential for high energy density: high permittivity of dielectric layers, thinness, and high resistance to breakdown of dielectric at high electric fields. Capacitors with strip material not impregnated with liquid.

  16. Visualization and analysis of pulsed ion beam energy density profile with infrared imaging

    Science.gov (United States)

    Isakova, Y. I.; Pushkarev, A. I.

    2018-03-01

    Infrared imaging technique was used as a surface temperature-mapping tool to characterize the energy density distribution of intense pulsed ion beams on a thin metal target. The technique enables the measuring of the total ion beam energy and the energy density distribution along the cross section and allows one to optimize the operation of an ion diode and control target irradiation mode. The diagnostics was tested on the TEMP-4M accelerator at TPU, Tomsk, Russia and on the TEMP-6 accelerator at DUT, Dalian, China. The diagnostics was applied in studies of the dynamics of the target cooling in vacuum after irradiation and in the experiments with target ablation. Errors caused by the target ablation and target cooling during measurements have been analyzed. For Fluke Ti10 and Fluke Ti400 infrared cameras, the technique can achieve surface energy density sensitivity of 0.05 J/cm2 and spatial resolution of 1-2 mm. The thermal imaging diagnostics does not require expensive consumed materials. The measurement time does not exceed 0.1 s; therefore, this diagnostics can be used for the prompt evaluation of the energy density distribution of a pulsed ion beam and during automation of the irradiation process.

  17. High spin studies with radioactive ion beams

    International Nuclear Information System (INIS)

    Garrett, J.D.

    1992-01-01

    The variety of new research possibilities afforded by the culmination of the two frontier areas of nuclear structure: high spin and studies far from nuclear stability (utilizing intense radioactive ion beams) are discussed. Topics presented include: new regions of exotic nuclear shape (e.g. superdeformation, hyperdeformation, and reflection-asymmetric shapes); the population of and consequences of populating exotic nuclear configurations; and complete spectroscopy (i.e. the overlap of state of the art low-and high-spin studies in the same nucleus)

  18. High spin studies with radioactive ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, J D [Oak Ridge National Lab., TN (United States)

    1992-08-01

    The variety of new research possibilities afforded by the culmination of the two frontier areas of nuclear structure: high spin and studies far from nuclear stability (utilizing intense radioactive ion beams) are discussed. Topics presented include: new regions of exotic nuclear shape (e.g. superdeformation, hyperdeformation, and reflection-asymmetric shapes); the population of and consequences of populating exotic nuclear configurations; and, complete spectroscopy (i.e. the overlap of state of the art low- and high-spin studies in the same nucleus). (author). 47 refs., 8 figs.

  19. Calculation of electronic stopping power along glancing swift heavy ion tracks in perovskites using ab initio electron density data

    Energy Technology Data Exchange (ETDEWEB)

    Osmani, O; Duvenbeck, A; Akcoeltekin, E; Meyer, R; Schleberger, M [Department of Physics, University of Duisburg-Essen, D-47048 Duisburg (Germany); Lebius, H [CIMAP, blvd Henri Becquerel, 14070 Caen (France)], E-mail: marika.schleberger@uni-due.de

    2008-08-06

    In recent experiments the irradiation of insulators of perovskite type with swift (E{approx}100 MeV) heavy ions under glancing incidence has been shown to provide a unique means to generate periodically arranged nanodots at the surface. The physical origin of these patterns has been suggested as stemming from a highly anisotropic electron density distribution within the bulk. In order to show the relevance of the electron density distribution of the target we present a model calculation for the system Xe{sup 23+} {yields} SrTiO{sub 3} that is known to produce the aforementioned surface modifications. On the basis of the Lindhard model of electronic stopping, we employ highly-resolved ab initio electron density data to describe the conversion of kinetic energy into excitation energy along the ion track. The primary particle dynamics are obtained via integration of the Newtonian equations of motion that are governed by a space- and time-dependent frictional force originating from Lindhard stopping. The analysis of the local electronic stopping power along the ion track reveals a pronounced periodic structure. The periodicity length varies strongly with the particular choice of the polar angle of incidence and is directly correlated to the experimentally observed formation of periodic nanodots at insulator surfaces.

  20. Near equality of ion phase space densities at earth, Jupiter, and Saturn

    Science.gov (United States)

    Cheng, A. F.; Krimigis, S. M.; Armstrong, T. P.

    1985-01-01

    Energetic-ion phase-space density profiles are strikingly similar in the inner magnetospheres of earth, Jupiter, and Saturn for ions of first adiabatic invariant near 100 MeV/G and small mirror latitudes. Losses occur inside L approximately equal to 7 for Jupiter and Saturn and inside L approximately equal to 5 at earth. At these L values there exist steep plasma-density gradients at all three planets, associated with the Io plasma torus at Jupiter, the Rhea-Dione-Tethys torus at Saturn, and the plasmasphere at earth. Measurements of ion flux-tube contents at Jupiter and Saturn by the low-energy charged-particle experiment show that these are similar (for O ions at L = 5-9) to those at earth (for protons at L = 2-6). Furthermore, the thermal-ion flux-tube contents from Voyager plasma-science data at Jupiter and Saturn are also very nearly equal, and again similar to those at earth, differing by less than a factor of 3 at the respective L values. The near equality of energetic and thermal ion flux-tube contents at earth, Jupiter, and Saturn suggests the possibility of strong physical analogies in the interaction between plasma and energetic particles at the plasma tori/plasma sheets of Jupiter and Saturn and the plasmasphere of earth.

  1. Variable kernel density estimation in high-dimensional feature spaces

    CSIR Research Space (South Africa)

    Van der Walt, Christiaan M

    2017-02-01

    Full Text Available Estimating the joint probability density function of a dataset is a central task in many machine learning applications. In this work we address the fundamental problem of kernel bandwidth estimation for variable kernel density estimation in high...

  2. The Influence of Decreased Levels of High Density Lipoprotein ...

    African Journals Online (AJOL)

    very low density lipoprotein cholesterol, and triglyceride were assayed. ... Abiodun and Gwarzo: Association of high density lipoprotein cholesterol with haemolysis in sickle cell disease ... analyses were carried out to determine the correlation.

  3. High-Latitude Neutral Mass Density Maxima

    Science.gov (United States)

    Huang, C. Y.; Huang, Y.; Su, Y.-J.; Huang, T.; Sutton, E. K.

    2017-10-01

    Recent studies have reported that thermospheric effects due to solar wind driving can be observed poleward of auroral latitudes. In these papers, the measured neutral mass density perturbations appear as narrow, localized maxima in the cusp and polar cap. They conclude that Joule heating below the spacecraft is the cause of the mass density increases, which are sometimes associated with local field-aligned current structures, but not always. In this paper we investigate neutral mass densities measured by accelerometers on the CHAllenging Minisatellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE) spacecraft from launch until years 2010 (CHAMP) and 2012 (GRACE), approximately 10 years of observations from each satellite. We extract local maxima in neutral mass densities over the background using a smoothing window with size of one quarter of the orbit. The maxima have been analyzed for each year and also for the duration of each set of satellite observations. We show where they occur, under what solar wind conditions, and their relation to magnetic activity. The region with the highest frequency of occurrence coincides approximately with the cusp and mantle, with little direct evidence of an auroral zone source. Our conclusions agree with the "hot polar cap" observations that have been reported and studied in the past.

  4. Effect of electrolysis parameters on the morphologies of copper powder obtained at high current densities

    Directory of Open Access Journals (Sweden)

    Orhan Gökhan

    2012-01-01

    Full Text Available The effects of copper ion concentrations and electrolyte temperature on the morphologies and on the apparent densities of electrolytic copper powders at high current densities under galvanostatic regime were examined. These parameters were evaluated by the current efficiency of hydrogen evolution. In addition, scanning electron microscopy was used for analyzing the morphology of the copper powders. It was found that the morphology was dependent over the copper ion concentration and electrolyte temperature under same current density (CD conditions. At 150 mA cm-2 and the potential of 1000±20 mV (vs. SCE, porous and disperse copper powders were obtained at low concentrations of Cu ions (0.120 M Cu2+ in 0.50 M H2SO4. Under this condition, high rate of hydrogen evolution reaction took place parallel to copper electrodeposition. The morphology was changed from porous, disperse and cauliflower-like to coral-like, shrub-like and stalk-stock like morphology with the increasing of Cu ion concentrations towards 0.120 M, 0.155 M, 0.315 M, 0.475 M and 0.630 M Cu2+ in 0.5 M H2SO4 respectively at the same CD. Similarly, as the temperature was increased, powder morphology and apparent density were observed to be changed. The apparent density values of copper powders were found to be suitable for many of the powder metallurgy applications.

  5. Scaling of energy confinement and poloidal beta in high density tokamaks

    NARCIS (Netherlands)

    Schram, D.C.; Schüller, F.C.

    1980-01-01

    A semi-empirical analysis of the heat balance of ohmically heated, high density Tokamak plasmas, shows that the observed heat transport can be explained by neoclassical (plateau) ion heat conduction in the central part of the plasma. Experimental values for Te, ß¿e, and tEe and the variation of

  6. Guidelines for etching silicon MEMS structures using fluorine high-density plasmas at cryogenic temperatures

    NARCIS (Netherlands)

    de Boer, Meint J.; Gardeniers, Johannes G.E.; Jansen, Henricus V.; Gilde, M.J.; Roelofs, Gerard; Sasserath, Jay N.; Elwenspoek, Michael Curt

    This paper presents guidelines for the deep reactive ion etching (DRIE) of silicon MEMS structures, employing SF6/O2-based high-density plasmas at cryogenic temperatures. Procedures of how to tune the equipment for optimal results with respect to etch rate and profile control are described. Profile

  7. Electron and Negative Ion Densities in C2F6 and CHF3 Containing Inductively Coupled Discharges

    International Nuclear Information System (INIS)

    HEBNER, GREGORY A.; MILLER, PAUL A.

    1999-01-01

    Electron and negative ion densities have been measured in inductively coupled discharges containing C 2 F 6 and CHF 3 . Line integrated electron density was determined using a microwave interferometer, negative ion densities were inferred using laser photodetachment spectroscopy, and electron temperature was determined using a Langmuir probe. For the range of induction powers, pressures and bias power investigated, the electron density peaked at 9 x 10 12 cm -2 (line-integrated) or approximately 9 x 10 11 cm -3 . The negative ion density peaked at approximately 1.3 x 10 11 cm -3 . A maximum in the negative ion density as a function of induction coil power was observed. The maximum is attributed to a power dependent change in the density of one or more of the potential negative ion precursor species since the electron temperature did not depend strongly on power. The variation of photodetachment with laser wavelength indicated that the dominant negative ion was F - . Measurement of the decay of the negative ion density in the afterglow of a pulse modulated discharge was used to determine the ion-ion recombination rate for CF 4 , C 2 F 6 and CHF 3 discharges

  8. Improvement of highly charged ion output from an ECR source

    International Nuclear Information System (INIS)

    Shirkov, G.D.

    1995-01-01

    The physical limitations of the highly charged ion production in the ECR source is analyzed in this report. General methods to increase the output ion current and the attainable charged states of heavy ions are discussed. Some new ways to improve the output of highly charged ions from the ECR source for heavy ions are proposed. A new library of computer codes for the mathematical simulation of heavy ion production in the ECR ion source is used for numerical experiments to test these ways for improving the operation of the ECR source. (orig.)

  9. Analytic theory of the Rayleigh-Taylor instability in a uniform density plasma-filled ion diode

    International Nuclear Information System (INIS)

    Hussey, T.W.; Payne, S.S.

    1987-04-01

    The J-vector x B-vector forces associated with the surface current of a plasma-filled ion diode will accelerate this plasma fill toward the anode surface. It is well known that such a configuration with a high I is susceptible to the hydromagnetic Rayleigh-Taylor instability in certain geometries. A number of ion diode plasma sources have been proposed, most of which have a falling density going away from the wall. A somewhat more unstable case, however, is that of uniform density. In this report we attempt to establish an upper limit on this effect with a simple analytic model in which a uniform-density plasma is accelerated by the magnetic field anticipated in a PBFA-II diode. We estimate the number of linear e-foldings experienced by an unstable surface as well as the most damaging wavelength initial perturbation. This model, which accounts approximately for stabilization due to field diffusion, suggests that even with a uniform fill, densities in excess of a few 10 15 are probably not damaged by the instability. In addition, even lower densities might be tolerated if perturbations near the most damaging wavelength can be kept very small

  10. Preparation and cooling of magnesium ion crystals for sympathetic cooling of highly charged ions in a Penning trap

    Energy Technology Data Exchange (ETDEWEB)

    Murboeck, Tobias

    2017-07-01

    important step towards the sympathetic cooling of highly charged ions (HCI) and paves the way to future investigations of HCI, which will enable a stringent test of bound-state quantum electrodynamics. For supply of HCI to the SpecTrap experiment, the HITRAP low-energy beamline - including the pulsed drift tubes for ion deceleration and the electron beam ion source - were commissioned. Ion bunches containing several tens of thousands of argon ions (Ar{sup 13+}) were transported to the SpecTrap Penning trap. These ion numbers are sufficient for future spectroscopy of the fine structure splitting in boron-like Ar{sup 13+}. In future experiments, the HCI shall be delivered by HITRAP and will possess large kinetic energies immediate after capture into the Penning trap, so that initial sympathetic cooling is not very efficient. Therefore, the SpecTrap Penning trap features axial resonators for pre-cooling of the HCI to the kelvin-regime by means of resistive cooling. An analytical model for resistive cooling of highly charged ions was developed in this work, which for the first time explained the measured resistive cooling signals of HCI given in literature. This model allows for a deeper understanding of the interaction between radial and axial degrees of freedom, it predicts the set of experimental parameters for optimum cooling, and it provides the time evolution of the HCI density and temperature during the cooling process.

  11. Transverse microanalysis of high energy Ion implants

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, S P; Jamieson, D N; Nugent, K W; Prawer, S [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1997-12-31

    High energy ion implants in semiconductor materials have been analyzed by Channeling Contrast Microscopy (CCM) perpendicular to the implant direction, allowing imaging of the entire ion track. The damage produced by Channeled and Random 1.4 MeV H{sup +} implants into the edge of a <100> type IIa diamond wafer were analyzed by channeling into the face of the crystal. The results showed negligible damage in the surface region of the implants, and swelling induced misalignment at the end of range of the implants. Channeled 1.4 MeV H{sup +} implants in diamond had a range only 9% deeper than Random implants, which could be accounted for by dechanneling of the beam. The channeling of H{sup +}{sub 2} ions has been previously found to be identical to that of protons of half energy, however the current experiment has shown a 1% increase in {chi}{sub min} for H{sup +}{sub 2} in diamond compared to H{sup +} at 1,2 MeV per proton. This is due to repulsion between protons within the same channel. 5 refs., 2 figs.

  12. Transverse microanalysis of high energy Ion implants

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, S.P.; Jamieson, D.N.; Nugent, K.W.; Prawer, S. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    High energy ion implants in semiconductor materials have been analyzed by Channeling Contrast Microscopy (CCM) perpendicular to the implant direction, allowing imaging of the entire ion track. The damage produced by Channeled and Random 1.4 MeV H{sup +} implants into the edge of a <100> type IIa diamond wafer were analyzed by channeling into the face of the crystal. The results showed negligible damage in the surface region of the implants, and swelling induced misalignment at the end of range of the implants. Channeled 1.4 MeV H{sup +} implants in diamond had a range only 9% deeper than Random implants, which could be accounted for by dechanneling of the beam. The channeling of H{sup +}{sub 2} ions has been previously found to be identical to that of protons of half energy, however the current experiment has shown a 1% increase in {chi}{sub min} for H{sup +}{sub 2} in diamond compared to H{sup +} at 1,2 MeV per proton. This is due to repulsion between protons within the same channel. 5 refs., 2 figs.

  13. Evaporative cooling of highly charged ions in EBIT [Electron Beam Ion Trap]: An experimental realization

    International Nuclear Information System (INIS)

    Schneider, M.B.; Levine, M.A.; Bennett, C.L.; Henderson, J.R.; Knapp, D.A.; Marrs, R.E.

    1988-01-01

    Both the total number and trapping lifetime of near-neon-like gold ions held in an electron beam ion trap have been greatly increased by a process of 'evaporative cooling'. A continuous flow of low-charge-state ions into the trap cools the high-charge-state ions in the trap. Preliminary experimental results using titanium ions as a coolant are presented. 8 refs., 6 figs., 2 tabs

  14. Progress on precision measurements of inner shell transitions in highly charged ions at an ECR ion source

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, Csilla I.; Indelicato, Paul; LeBigot, Eric-Olivier; Vallette, Alexandre; Amaro, Pedro; Guerra, Mauro; Gumberidze, Alex [Laboratoire Kastler Brossel, Ecole Normale Superieure, CNRS, Universite Pierre et Marie Curie- Paris 6, Case 74, 4 place Jussieu, F-75005 Paris (France); Centro de Fisica Atomica, CFA, Departamento de Fisica (Portugal); Faculdade de Ciencias e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Laboratoire Kastler Brossel, Ecole Normale Superieure, CNRS, Universite Pierre et Marie Curie- Paris 6, Case 74, 4 place Jussieu, F-75005 Paris (France)

    2012-05-25

    Inner shell transitions of highly charged ions produced in the plasma of an Electron Cyclotron Resonance Ion Source (ECRIS) were observed the first time by a Double Crystal Spectrometer (DCS). The DCS is a well-used tool in precision x-ray spectroscopy due to its ability of precision wavelength measurement traced back to a relative angle measurement. Because of its requirement for a bright x-ray source the DCS has not been used before in direct measurements of highly charged ions (HCI). Our new precision measurement of inner shell transitions in HCI is not just going to provide new x-ray standards for quantum metrology but can also give information about the plasma in which the ions reside. Ionic temperatures and with that the electron density can be determined by thorough examination of line widths measured with great accuracy.

  15. An investigation of pulsed high density plasmas

    International Nuclear Information System (INIS)

    Timmermans, C.J.

    1984-01-01

    In this thesis a wall-stabilized argon cascade arc is studied at values of pulsed pressure up to 14 bar and a pulsed current range up to 2200 A with a time duration of about 2 ms. The basic plasma is a CW cascade arc with a 5 mm diameter plasma column and a length of 90 mm, which operates at a 60 A DC current and at one atmosphere filling pressure. The author starts with an extensive summary of the CW arc investigations. After a brief introduction of the basic transport equations the mass equations of the constituent particles are treated using the extended collisional radiative model. The energy balance equations and the momentum balance are discussed. The electron density is determined from measurements of the continuum radiation. The final chapter contains the experimental results on the electron temperatures and electron densities in the pressure and current pulsed plasma. Attention is given to the deviations from local thermodynamic equilibrium values of the ground level densities of the different argon systems. (Auth.)

  16. Development of high temperature superconductors having high critical current density

    International Nuclear Information System (INIS)

    Hong, Gye Wong; Kim, C. J.; Lee, H.G.; Kwon, S. C.; Lee, H. J.; Kim, K. B.; Park, J. Y.; Jung, C. H.

    2000-08-01

    Fabrication of high T c superconductors and its applications for electric power device were carried out for developing superconductor application technologies. High quality YBCO superconductors was fabricated by melt texture growth, top-seeded melt growth process and multi-seeded melt growth process and the properties was compared. The critical current density of the melt processed YBCO superconductors was about few 10,000 A/cm 2 and the levitation force was 50 N. The processing time needed for the growth of the 123 single grain was greatly reduced by applying multi-seeding without no significant degradation of the levitation force. The multi-seeded melt growth process was confirmed as a time-saving and cost-effective method for the fabrication of bulk superconductors with controlled crystallographic orientation

  17. Development of high temperature superconductors having high critical current density

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Gye Wong; Kim, C. J.; Lee, H.G.; Kwon, S. C.; Lee, H. J.; Kim, K. B.; Park, J. Y.; Jung, C. H

    2000-08-01

    Fabrication of high T{sub c} superconductors and its applications for electric power device were carried out for developing superconductor application technologies. High quality YBCO superconductors was fabricated by melt texture growth, top-seeded melt growth process and multi-seeded melt growth process and the properties was compared. The critical current density of the melt processed YBCO superconductors was about few 10,000 A/cm{sup 2} and the levitation force was 50 N. The processing time needed for the growth of the 123 single grain was greatly reduced by applying multi-seeding without no significant degradation of the levitation force. The multi-seeded melt growth process was confirmed as a time-saving and cost-effective method for the fabrication of bulk superconductors with controlled crystallographic orientation.

  18. Line radiation of multicharged ions with the Fermi-Dirac level distribution of electrons at high temperatures

    International Nuclear Information System (INIS)

    Garanin, S.F.

    2003-01-01

    Line radiation of multicharged ions with the Fermi-Dirac electron distribution by levels in the range of plasma temperatures, when electron movement may be considered quasiclassical, while potential, in which they move, is the Coulomb one, is considered. The spectrum and intensity of ion radiation are calculated. Within high plasma densities the radiation intensity per one ion proved to be independent of density and proportional to T 2 [ru

  19. Restoring the consistency with the contact density theorem of a classical density functional theory of ions at a planar electrical double layer.

    Science.gov (United States)

    Gillespie, Dirk

    2014-11-01

    Classical density functional theory (DFT) of fluids is a fast and efficient theory to compute the structure of the electrical double layer in the primitive model of ions where ions are modeled as charged, hard spheres in a background dielectric. While the hard-core repulsive component of this ion-ion interaction can be accurately computed using well-established DFTs, the electrostatic component is less accurate. Moreover, many electrostatic functionals fail to satisfy a basic theorem, the contact density theorem, that relates the bulk pressure, surface charge, and ion densities at their distances of closest approach for ions in equilibrium at a smooth, hard, planar wall. One popular electrostatic functional that fails to satisfy the contact density theorem is a perturbation approach developed by Kierlik and Rosinberg [Phys. Rev. A 44, 5025 (1991)PLRAAN1050-294710.1103/PhysRevA.44.5025] and Rosenfeld [J. Chem. Phys. 98, 8126 (1993)JCPSA60021-960610.1063/1.464569], where the full free-energy functional is Taylor-expanded around a bulk (homogeneous) reference fluid. Here, it is shown that this functional fails to satisfy the contact density theorem because it also fails to satisfy the known low-density limit. When the functional is corrected to satisfy this limit, a corrected bulk pressure is derived and it is shown that with this pressure both the contact density theorem and the Gibbs adsorption theorem are satisfied.

  20. Sputtered thin films for high density tape recording

    NARCIS (Netherlands)

    Nguyen, L.T.

    This thesis describes the investigation of sputtered thin film media for high density tape recording. As discussed in Chapter 1, to meet the tremendous demand of data storage, the density of recording tape has to be increased continuously. For further increasing the bit density the key factors are:

  1. Pseudoclassical approach to electron and ion density correlations in simple liquid metals

    International Nuclear Information System (INIS)

    Vericat, F.; Tosi, M.P.; Pastore, G.

    1986-04-01

    Electron-electron and electron-ion structural correlations in simple liquid metals are treated by using effective pair potentials to incorporate quantal effects into a pseudoclassical description of the electron fluid. An effective pair potential between simultaneous electron density fluctuations is first constructed from known properties of the degenerate jellium model, which are the plasmon sum rule, the Kimball-Niklasson relation and Yasuhara's values of the electron pair distribution function at contact. An analytic expression is thereby obtained in the Debye-Hueckel approximation for the electronic structure factor in jellium over a range of density appropriate to metals, with results which compare favourably with those of fully quantal evaluations. A simple pseudoclassical model is then set up for a liquid metal: this involves a model of charged hard spheres for the ion-ion potential and an empty core model for the electron-ion potential, the Coulombic tails being scaled as required by the relation between the long-wavelength partial structure factors and the isothermal compressibility of the metal. The model is solved analytically by a pseudoclassical linear response treatment of the electron-ion coupling and numerical results are reported for partial structure factors in liquid sodium and liquid beryllium. Contact is made for the latter system with data on the electron-electron structure factor in the crystal from inelastic X-ray scattering experiments of Eisenberger, Marra and Brown. (author)

  2. Improvement of highly charged ion production in the ECR source of heavy ions

    International Nuclear Information System (INIS)

    Shirkov, G.D.

    1996-01-01

    Some physical limitations of the highly charged ion production in the ECR source are analyzed in this report. A few possible ways to improve the output of highly charged ions from the ECR source for heavy ions are proposed. A new library of computer codes for the numerical simulation of heavy ion production in the ECR ion source is used to examine these ways to improve the ECR source operation according to the CERN program of heavy ion acceleration. copyright 1996 American Institute of Physics

  3. Hierarchically porous carbon with high-speed ion transport channels for high performance supercapacitors

    Science.gov (United States)

    Lu, Haoyuan; Li, Qingwei; Guo, Jianhui; Song, Aixin; Gong, Chunhong; Zhang, Jiwei; Zhang, Jingwei

    2018-01-01

    Hierarchically porous carbons (HPC) are considered as promising electrode materials for supercapacitors, due to their outstanding charge/discharge cycling stabilities and high power densities. However, HPC possess a relatively low ion diffusion rate inside the materials, which challenges their application for high performance supercapacitor. Thus tunnel-shaped carbon pores with a size of tens of nanometers were constructed by inducing the self-assembly of lithocholic acid with ammonium chloride, thereby providing high-speed channels for internal ion diffusion. The as-formed one-dimensional pores are beneficial to the activation process by KOH, providing a large specific surface area, and then facilitate rapid transport of electrolyte ions from macropores to the microporous surfaces. Therefore, the HPC achieve an outstanding gravimetric capacitance of 284 F g-1 at a current density of 0.1 A g-1 and a remarkable capacity retention of 64.8% when the current density increases by 1000 times to 100 A g-1.

  4. High density internal transport barriers for burning plasma operation

    Energy Technology Data Exchange (ETDEWEB)

    Ridolfini, V Pericoli [Associazione EURATOM-ENEA sulla Fusione, CR Frascati, Rome (Italy); Barbato, E [Associazione EURATOM-ENEA sulla Fusione, CR Frascati, Rome (Italy); Buratti, P [Associazione EURATOM-ENEA sulla Fusione, CR Frascati, Rome (Italy)] (and others)

    2005-12-15

    A tokamak plasma with internal transport barriers (ITBs) is the best candidate for a steady ITER operation, since the high energy confinement allows working at plasma currents (I{sub p}) lower than the reference scenario. To build and sustain an ITB at the ITER high density ({>=}10{sup 20} m{sup -3}) and largely dominant electron (e{sup -}) heating is not trivial in most existing tokamaks. FTU can instead meet both requests, thanks to its radiofrequency heating systems, lower hybrid (LH, up to 1.9 MW) and electron cyclotron (EC up to 1.2 MW). By the combined use of them, ITBs are obtained up to peak densities n{sub e0} > 1.3 x 10{sup 20} m{sup -3}, with central e{sup -} temperatures T{sub e0} {approx} 5.5 keV, and are sustained for as long as the heating pulse is applied (>35 confinement times, {tau}{sub E}). At n{sub e0} {approx} 0.8 x 10{sup 20} m{sup -3} T{sub e0} can be larger than 11 keV. Almost full current drive (CD) and an overall good steadiness is attained within about one {tau}{sub E}, 20 times faster than the ohmic current relaxation time. The ITB extends over a central region with an almost flat or slightly reversed q profile and q{sub min} {approx} 1.3 that is fully sustained by off-axis lower hybrid current drive. Consequent to this is the beneficial good alignment of the bootstrap current, generated by the ITB large pressure gradients, with the LH driven current. Reflectometry shows a clear change in the turbulence close to the ITB radius, consistent with the reduced e{sup -} transport. Ions (i{sup +}) are significantly heated via collisions, but thermal equilibrium with electrons cannot be attained since the e{sup -}-i{sup +} equipartition time is always 4-5 times longer than {tau}{sub E}. No degradation of the overall ion transport, rather a reduction of the i{sup +} heat diffusivity, is observed inside the ITB. The global confinement has been improved up to 1.6 times over the scaling predictions. The ITB radius can be controlled by adjusting the

  5. Using NEG-pumping near a high density internal target

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, Alexander; Marton, Johann; Widmann, Eberhard; Zmeskal, Johann [Stefan Meyer Institut fuer Subatomare Physik, OeAW (Germany); Orth, Herbert [GSI, Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany)

    2009-07-01

    The universal detector PANDA will be constructed at the future high-energy antiproton storage ring HESR at FAIR (Facility for Antiproton and Ion Research, GSI/Darmstadt). It will use antiproton beams (1.5 to 15 GeV/c) for hadron physics in the charmonium region. The Stefan Meyer Institut (SMI) contributes to major parts of the PANDA detector like the hydrogen cluster-jet target and the vacuum system of the antiproton - target interaction zone. To ensure low background, the residual gas load in the interaction zone and in the antiproton beam-pipe has to be minimised. Most of the gas load will come from the high density internal hydrogen target. As the detector will cover almost the full solid angle, the installation of pumps near the interaction zone is impossible. Therefore the use of NEG (non-evaporative-getter) coated beam pipes has been considered as an alternative. Two setups with NEG coated tubes have been installed at SMI as prototypes of the PANDA interaction zone. General parameters of the NEG-film, its outgassing behaviour, the pumping speed and the pumping capacity for hydrogen have been tested. The results of the studies on the PANDA-interaction region are presented.

  6. Using NEG-pumping near a high density internal target

    International Nuclear Information System (INIS)

    Gruber, A.; Marton, J.; Widmann, E.; Zmeskal, J.; Orth, H.

    2008-01-01

    Full text: The Stefan Meyer Institut (SMI) is part of the international PANDA collaboration. The universal detector will be constructed at the future high-energy antiproton storage ring HESR at FAIR (Facility for Antiproton and Ion Research, GSI/Darmstadt). PANDA will use antiproton beams (1.5 to 15 GeV/c) for hadron physics in the charmonium region. SMI contributes to major parts of the PANDA detector like the hydrogen cluster-jet target and the vacuum system of the antiproton - target interaction zone. To ensure low background, the residual gas load in the interaction zone and in the antiproton beam-pipe has to be minimized. Most of the gas load, of course will come from the high density internal hydrogen target. Since the PANDA detector will cover almost the full solid angle, the installation of pumps near the interaction zone is impossible. Therefore, the use of NEG (non-evaporative-getter) coated beam pipes has been considered as an alternative. Two setups with NEG coated tubes have been installed at SMI as prototypes of the PANDA interaction zone. The outgassing behavior, the pumping speed and the pumping capacity for hydrogen have been tested. The status of the studies of the interaction region will be presented. (author)

  7. High Efficiency, High Density Terrestrial Panel. [for solar cell modules

    Science.gov (United States)

    Wohlgemuth, J.; Wihl, M.; Rosenfield, T.

    1979-01-01

    Terrestrial panels were fabricated using rectangular cells. Packing densities in excess of 90% with panel conversion efficiencies greater than 13% were obtained. Higher density panels can be produced on a cost competitive basis with the standard salami panels.

  8. High-current pulsed ion source for metallic ions

    International Nuclear Information System (INIS)

    Gavin, B.; Abbott, S.; MacGill, R.; Sorensen, R.; Staples, J.; Thatcher, R.

    1981-03-01

    A new sputter-ion PIG source and magnet system, optimized for intermediate charge states, q/A of 0.02 to 0.03, is described. This source will be used with the new Wideroe-based injector for the SuperHILAC. Pulsed electrical currents of several emA of heavy metal ions have been produced in a normalized emittance area of .05π cm-mr. The source system is comprised of two electrically separate anode chambers, one in operation and one spare, which can be selected by remote control. The entire source head is small and quickly removable

  9. Reflection and absorption of ion-acoustic waves in a plasma density gradient

    International Nuclear Information System (INIS)

    Ishihara, O.

    1977-01-01

    Plasma is characterized by electrical quasineutrality and the collective behavior. There exists a longitudinal low-frequency wave called an ion-acoustic wave in a plasma. One problem in the experimental study of ion-acoustic waves has been that sometimes they are observed to be reflected from discharge tube walls, and sometimes to be absorbed. Theoretical computation reveals that a velocity gradient produced by a density gradient plays a significant role in the reflection. The velocity gradient produces the subsonic-supersonic transition and long wavelength waves are reflected before reaching the transition while short wavelength waves penetrate over the transition and are absorbed in the supersonic flow plasma

  10. Setup of an ion-beam facility for the nanostructuration of 2D materials with highly charged ions

    International Nuclear Information System (INIS)

    Hopster, Johannes

    2014-01-01

    This work deals with the interaction of highly charged ions with surfaces. When an ion approaches a surface, its potential energy is deposited into the surface via a cascade of electronic processes. A strong electronic excitation of the surface results, which is localized in a nanometer sized region. As a consequence of further mechanisms, this excitation may lead to nanostructures being of topographic, structural or chemical modifications of the material. During this work, a setup of a complete ion beamline was constructed. The beamline offers production, focussing and charge separation of ion beams as well as irradiations of surfaces with highly charged ions. Additionally, new methods for beam profile and particle density analysis via Raman microscopy on graphene are presented. Experimental results of highly charged ions impinging on 2D materials provide the second part of this work. Ion induced nanostructures on lamellar materials, i.e. MoS 2 as well as single layers of graphene, could be identified and analyzed. Each of them were triggered by the potential energy of the ions. Processes of the ion surface interaction could be deduced qualitatively from the data. Local regions of enhanced friction on graphene could be detected by Friction Force Microscopy after irradiations. Thresholds for defect creation were established regarding the potential energy, which depend strongly on the kinetic energy of the ions. In terms of the over the barrier model, this dependency could be related to the time of flight the ion spends above the surface. Defects on irradiated graphene as well as on free standing graphene were analyzed via Raman microscopy. Possible dependencies of the defect diameters and nature on the layer number as well as on the presence of a substrate were proved. It was shown, that graphene becomes locally hydrogenated by the impact of highly charged ions. Such a chemical modification leads to an enhanced friction as well as to an appearance of defect modes

  11. Robust, High Capacity, High Power Lithium Ion Batteries for Space Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Lithium ion battery technology provides the highest energy density of all rechargeable battery technologies available today. However, the majority of the research...

  12. High-Power Ion Thruster Technology

    Science.gov (United States)

    Beattie, J. R.; Matossian, J. N.

    1996-01-01

    Performance data are presented for the NASA/Hughes 30-cm-diam 'common' thruster operated over the power range from 600 W to 4.6 kW. At the 4.6-kW power level, the thruster produces 172 mN of thrust at a specific impulse of just under 4000 s. Xenon pressure and temperature measurements are presented for a 6.4-mm-diam hollow cathode operated at emission currents ranging from 5 to 30 A and flow rates of 4 sccm and 8 sccm. Highly reproducible results show that the cathode temperature is a linear function of emission current, ranging from approx. 1000 C to 1150 C over this same current range. Laser-induced fluorescence (LIF) measurements obtained from a 30-cm-diam thruster are presented, suggesting that LIF could be a valuable diagnostic for real-time assessment of accelerator-arid erosion. Calibration results of laminar-thin-film (LTF) erosion badges with bulk molybdenum are presented for 300-eV xenon, krypton, and argon sputtering ions. Facility-pressure effects on the charge-exchange ion current collected by 8-cm-diam and 30-cm-diam thrusters operated on xenon propellant are presented to show that accel current is nearly independent of facility pressure at low pressures, but increases rapidly under high-background-pressure conditions.

  13. High Energy Density Dielectrics for Pulsed Power Applications

    National Research Council Canada - National Science Library

    Wu, Richard L; Bray, Kevin R

    2008-01-01

    This report was developed under a SBIR contract. Aluminum oxynitride (AlON) capacitors exhibit several promising characteristics for high energy density capacitor applications in extreme environments...

  14. SIMULATIONS OF HIGH-VELOCITY CLOUDS. I. HYDRODYNAMICS AND HIGH-VELOCITY HIGH IONS

    International Nuclear Information System (INIS)

    Kwak, Kyujin; Henley, David B.; Shelton, Robin L.

    2011-01-01

    We present hydrodynamic simulations of high-velocity clouds (HVCs) traveling through the hot, tenuous medium in the Galactic halo. A suite of models was created using the FLASH hydrodynamics code, sampling various cloud sizes, densities, and velocities. In all cases, the cloud-halo interaction ablates material from the clouds. The ablated material falls behind the clouds where it mixes with the ambient medium to produce intermediate-temperature gas, some of which radiatively cools to less than 10,000 K. Using a non-equilibrium ionization algorithm, we track the ionization levels of carbon, nitrogen, and oxygen in the gas throughout the simulation period. We present observation-related predictions, including the expected H I and high ion (C IV, N V, and O VI) column densities on sightlines through the clouds as functions of evolutionary time and off-center distance. The predicted column densities overlap those observed for Complex C. The observations are best matched by clouds that have interacted with the Galactic environment for tens to hundreds of megayears. Given the large distances across which the clouds would travel during such time, our results are consistent with Complex C having an extragalactic origin. The destruction of HVCs is also of interest; the smallest cloud (initial mass ∼ 120 M sun ) lost most of its mass during the simulation period (60 Myr), while the largest cloud (initial mass ∼ 4 x 10 5 M sun ) remained largely intact, although deformed, during its simulation period (240 Myr).

  15. Measurement of few-electron uranium ions on a high-energy electron beam ion trap

    International Nuclear Information System (INIS)

    Beiersdorfer, P.

    1994-01-01

    The high-energy electron beam ion trap, dubbed Super-EBIT, was used to produce, trap, and excite uranium ions as highly charged as fully stripped U 92+ . The production of such highly charged ions was indicated by the x-ray emission observed with high-purity Ge detectors. Moreover, high-resolution Bragg crystal spectromters were used to analyze the x-ray emission, including a detailed measurement of both the 2s 1/2 -2p 3/2 electric dipole and 2p 1/2 -2p 3/2 magnetic dipole transitions. Unlike in ion accelerators, where the uranium ions move at relativistic speeds, the ions in this trap are stationary. Thus very precise measurements of the transition energies could be made, and the QED contribution to the transition energies could be measured within less than 1 %. Details of the production of these highly charged ions and their measurement is given

  16. Plasma ion emission from high intensity picosecond laser pulse interactions with solid targets

    International Nuclear Information System (INIS)

    Fews, A.P.; Norreys, P.A.; Beg, F.N.; Bell, A.R.; Dangor, A.E.; Danson, C.N.; Lee, P.; Rose, S.J.

    1994-01-01

    The fast ion emission from high intensity, picosecond laser plasmas has been measured to give the characteristic ion energy and the amount of laser energy transferred to ions with energies ≥100 keV/nucleon as a function of incident intensity. The characteristic ion energy varies from 0.2 to 1.3 MeV over the range 2.0x10 17 --2.0x10 18 W cm -2 . Ten percent of the laser energy is transferred into MeV ions at 2.0x10 18 W cm -2 . Calculations of stopping power in high density materials are presented that show that fast ions cannot be ignored in modeling fast ignitor schemes

  17. Comparison of ion temperature and ion density measured during geomagnetically very quiet conditions on board of the geophysical rocket ''Vertical-6'' with the international reference ionosphere

    International Nuclear Information System (INIS)

    Bencze, P.; Kovacs, K.; Apathy, I.; Szemerey, I.; Afonin, V.; Bezrukih, V.; Shutte, N.

    1980-05-01

    Ion temperature and ion density, measured on October 25, 1977 during the flight of the geophyisical rocket ''Vertical-6'' by means of a group of five retarding potential analyzers looking into different directions of space, are compared with the International Reference Ionosphere 1978. The measurements were carried out in a geomagnetically quiet period to a height of 1500 km. The results show that both the ion temperature and the ion density are lower than the values predicted by the Reference Ionosphere, the difference is decreasing with increasing altitude. (author)

  18. ADX: a high field, high power density, Advanced Divertor test eXperiment

    Science.gov (United States)

    Vieira, R.; Labombard, B.; Marmar, E.; Irby, J.; Shiraiwa, S.; Terry, J.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; ADX Team

    2014-10-01

    The MIT PSFC and collaborators are proposing an advanced divertor experiment (ADX) - a tokamak specifically designed to address critical gaps in the world fusion research program on the pathway to FNSF/DEMO. This high field (6.5 tesla, 1.5 MA), high power density (P/S ~ 1.5 MW/m2) facility would utilize Alcator magnet technology to test innovative divertor concepts for next-step DT fusion devices (FNSF, DEMO) at reactor-level boundary plasma pressures and parallel heat flux densities while producing high performance core plasma conditions. The experimental platform would also test advanced lower hybrid current drive (LHCD) and ion-cyclotron range of frequency (ICRF) actuators and wave physics at the plasma densities and magnetic field strengths of a DEMO, with the unique ability to deploy launcher structures both on the low-magnetic-field side and the high-field side - a location where energetic plasma-material interactions can be controlled and wave physics is most favorable for efficient current drive, heating and flow drive. This innovative experiment would perform plasma science and technology R&D necessary to inform the conceptual development and accelerate the readiness-for-deployment of FNSF/DEMO - in a timely manner, on a cost-effective research platform. Supported by DE-FC02-99ER54512.

  19. A low emittance and uniform density Cs+ source for heavy ion induction linacs

    International Nuclear Information System (INIS)

    Henestroza, E.; Eylon, S.

    1990-01-01

    A heavy-ion induction linac experiment (MBE-4) in progress at LBL is studying the transport and acceleration of space-charge-dominated beams in a long alternate gradient focusing channel. Recent studies of the transverse beam dynamics suggested that characteristics of the injector geometry were contributing to the normalized transverse emittance growth. Phase space and current density distribution measurements of the beam extracted from the injector revealed aberrations and a hollow density profile. Based on EGUN calculations the authors redesigned the 10 mA injector for MBE-4 by modifying the cathode: Pierce electrode and using a curved emitting surface. The simulation predicts an extracted beam with less aberrations and a flat density profile. A test stand was used to check the new design. The density profile has measured and found to be in agreement with the numerical simulation

  20. High density, high magnetic field concepts for compact fusion reactors

    International Nuclear Information System (INIS)

    Perkins, L.J.

    1996-01-01

    One rather discouraging feature of our conventional approaches to fusion energy is that they do not appear to lend themselves to a small reactor for developmental purposes. This is in contrast with the normal evolution of a new technology which typically proceeds to a full scale commercial plant via a set of graduated steps. Accordingly' several concepts concerned with dense plasma fusion systems are being studied theoretically and experimentally. A common aspect is that they employ: (a) high to very high plasma densities (∼10 16 cm -3 to ∼10 26 cm -3 ) and (b) magnetic fields. If they could be shown to be viable at high fusion Q, they could conceivably lead to compact and inexpensive commercial reactors. At least, their compactness suggests that both proof of principle experiments and development costs will be relatively inexpensive compared with the present conventional approaches. In this paper, the following concepts are considered: (1) The staged Z-pinch, (2) Liner implosion of closed-field-line configurations, (3) Magnetic ''fast'' ignition of inertial fusion targets, (4) The continuous flow Z-pinch

  1. High Tap Density Li4Ti5O12 Microspheres: Synthetic Conditions and Advanced Electrochemical Performance

    KAUST Repository

    Ming, Jun; Zheng, Junwei; Zhou, Qun; Ren, Jianxin; Ming, Hai; Jia, Zhenyong; Zhang, Yanqing

    2017-01-01

    Preparation of uniform spherical Li4Ti5O12 with high tap density is significant to achieve a high volumetric energy density in lithium-ion batteries. Herein, Li4Ti5O12 micro-spheres with variable tap-density and tunable size distribution were synthesized by a newly designed industrial spray drying approach. The slurry concentration, sintering time and sintering conditions after spray, the effect of Li/Ti molar ratio on the lithium ion (Li+) storage capability were investigated. A narrow particle size distribution around 10 μm and high tap-density close to 1.4 g cm-3 of the Li4Ti5O12 spheres can be obtained under the optimized conditions. The Li4Ti5O12 spheres can deliver much higher capacity of 168 mAh g-1 at 1 C-rate and show high capacity retention of 97.7% over 400 cycles. The synthetic conditions are confirmed to be critical for improving the electron conductivity and Li+ diffusivity by adjusting the crystal and spatial structures. As-prepared high performance Li4Ti5O12 is an ideal electrode for Li-ion batteries or capacitors; meanwhile the presented approach is also applicable for preparing other kind of spherical materials.

  2. High Tap Density Li4Ti5O12 Microspheres: Synthetic Conditions and Advanced Electrochemical Performance

    KAUST Repository

    Ming, Jun

    2017-03-17

    Preparation of uniform spherical Li4Ti5O12 with high tap density is significant to achieve a high volumetric energy density in lithium-ion batteries. Herein, Li4Ti5O12 micro-spheres with variable tap-density and tunable size distribution were synthesized by a newly designed industrial spray drying approach. The slurry concentration, sintering time and sintering conditions after spray, the effect of Li/Ti molar ratio on the lithium ion (Li+) storage capability were investigated. A narrow particle size distribution around 10 μm and high tap-density close to 1.4 g cm-3 of the Li4Ti5O12 spheres can be obtained under the optimized conditions. The Li4Ti5O12 spheres can deliver much higher capacity of 168 mAh g-1 at 1 C-rate and show high capacity retention of 97.7% over 400 cycles. The synthetic conditions are confirmed to be critical for improving the electron conductivity and Li+ diffusivity by adjusting the crystal and spatial structures. As-prepared high performance Li4Ti5O12 is an ideal electrode for Li-ion batteries or capacitors; meanwhile the presented approach is also applicable for preparing other kind of spherical materials.

  3. Highly Supersonic Ion Pulses in a Collisionless Magnetized Plasma

    DEFF Research Database (Denmark)

    Juul Rasmussen, Jens; Schrittwieser, R.

    1982-01-01

    The initial transient response of a collisionless plasma to a high positive voltage step is investigated. Four different pulses are observed. An electron plasma wave pulse is followed by an ion burst. The latter is overtaken and absorbed by a highly supersonic ion pulse. Thereafter, an ion...

  4. Profiles of plasma parameters and density of negative hydrogen ions by laser detachment measurements in RF-driven ion sources; Profile der Plasmaparameter und Dichte negativer Wasserstoffionen mittels Laserdetachmentmessungen in HF-angeregten Ionenquellen

    Energy Technology Data Exchange (ETDEWEB)

    Christ-Koch, Sina

    2007-12-20

    This work shows the application of the Laserdetachment method for spatially resolved measurements of negative Hydrogen/Deuterium ion density. It was applied on a high power low pressure RF-driven ion source. The Laser detachment method is based on the measurement of electron currents on a positively biased Langmuir probe before and during/after a laser pulse. The density ratio of negative ions to electrons can be derived from the ratio of currents to the probe. The absolute density of negative ions can be obtained when the electron density is measured with the standard Langmuir probe setup. Measurements with the Langmuir probe additionally yield information about the floating and plasma potential, the electron temperature and the density of positive ions. The Laser detachment setup had to be adapted to the special conditions of the RF-driven source. In particular the existence of RF fields (1 MHz), high source potential (-20 kV), magnetic fields ({proportional_to} 7 mT) and caesium inside the source had to be considered. The density of negative ions could be identified in the range of n(H{sup -})=1.10{sup 17} 1/m{sup 3}, which is in the same order of magnitude as the electron density. Only the application of the Laser detachment method with the Langmuir probe measurements will yield spatially resolved plasma parameters and H- density profiles. The influence of diverse external parameters, such as pressure, RF-power, magnetic fields on the plasma parameters and their profiles were studied and explained. Hence, the measurements lead to a detailed understanding of the processes inside the source. (orig.)

  5. Bremsstrahlung spectra for Al, Cs, and Au atoms in high-temperature, high-density plasmas

    International Nuclear Information System (INIS)

    Kim, L.; Pratt, R.H.; Tseng, H.K.

    1985-01-01

    Results are presented from a numerical calculation for the bremsstrahlung spectrum and Gaunt factors of Al, Cs, and Au atoms in high-temperature (-T), high-density (-rho) plasmas. Plasma temperatures kT = 0.1 and 1.0 keV and plasma densities rho = rho 0 (the normal solid density) and rho = 100rho 0 are considered. This allows us to determine the generality and identify the origins of features which we had previously identified in calculations for Cs. We also now present results for the total energy loss of an electron in such a plasma. We use a relativistic multipole code which treats the bremsstrahlung process as a single-electron transition in a static screened central potential. We take for the static potential corresponding to an atom in a hot dense plasma the finite-temperature, finite-density Thomas-Fermi model. This approach corresponds to an average atom in local thermodynamic equilibrium. In comparison to isolated-neutral-atom results we observe general suppression of cross sections and a particular suppression in the tip region of the spectrum. Within this model, both superscreening and shape resonances are found in the circumstances of extreme density. At more normal densities and except for the soft-photon end, the spectrum at these energies for an atom in a hot plasma (characterized by an average degree of ionization) can be well represented by the spectrum of the corresponding isolated ion, which has a similar potential shape at the distances which characterize the process

  6. Probing the nuclear symmetry energy at high densities with nuclear reactions

    Science.gov (United States)

    Leifels, Y.

    2017-11-01

    The nuclear equation of state is a topic of highest current interest in nuclear structure and reactions as well as in astrophysics. The symmetry energy is the part of the equation of state which is connected to the asymmetry in the neutron/proton content. During recent years a multitude of experimental and theoretical efforts on different fields have been undertaken to constraint its density dependence at low densities but also above saturation density (ρ_0=0.16 fm ^{-3} . Conventionally the symmetry energy is described by its magnitude S_v and the slope parameter L , both at saturation density. Values of L = 44 -66MeV and S_v=31 -33MeV have been deduced in recent compilations of nuclear structure, heavy-ion reaction and astrophysics data. Apart from astrophysical data on mass and radii of neutron stars, heavy-ion reactions at incident energies of several 100MeV are the only means do access the high density behaviour of the symmetry energy. In particular, meson production and collective flows upto about 1 AGeV are predicted to be sensitive to the slope of the symmetry energy as a function of density. From the measurement of elliptic flow of neutrons with respect to charged particles at GSI, a more stringent constraint for the slope of the symmetry energy at supra-saturation densities has been deduced. Future options to reach even higher densities will be discussed.

  7. Performance of Novel Randomly Oriented High Graphene Carbon in Lithium Ion Capacitors

    Directory of Open Access Journals (Sweden)

    Rahul S. Kadam

    2018-01-01

    Full Text Available The structure of carbon material comprising the anode is the key to the performance of a lithium ion capacitor. In addition to determining the capacity, the structure of the carbon material also determines the diffusion rate of the lithium ion into the anode which in turn controls power density which is vital in high rate applications. This paper covers details of systematic investigation of the performance of a structurally novel carbon, called Randomly Oriented High Graphene (ROHG carbon, and graphite in a high rate application device, that is, lithium ion capacitor. Electrochemical impedance spectroscopy shows that ROHG is less resistive and has faster lithium ion diffusion rates (393.7 × 10−3 S·s(1/2 compared to graphite (338.1 × 10−3 S·s(1/2. The impedance spectroscopy data is supported by the cell data showing that the ROHG carbon based device has energy density of 22.8 Wh/l with a power density of 4349.3 W/l, whereas baseline graphite based device has energy density of 5 Wh/l and power density of 4243.3 W/l. This data clearly shows advantage of the randomly oriented graphene platelet structure of ROHG in lithium ion capacitor performance.

  8. Fast-scan monitor examines neutral-beam ion-density profile

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    All of the magnetic mirror confinement fusion experiments at LLL and at other laboratories depend on pulsed, energetic neutral-beam injection for fueling and imparting energy to the trapped plasma for density build-up and stability studies. It is vital to be able to monitor how well the injected ion beam is aimed and focused. To do this, we have designed an ion-beam current-density profile monitor that uses a commercial minimodular data acquisition system. Our prototype model monitors a single 20-kV, 50-A, 10-ms beam. However, the method is applicable to any number of beams with similar sampling target arrays. Also, the electronics can be switched to monitor any one of several target collectors

  9. ON THE ORIGIN OF THE HIGH COLUMN DENSITY TURNOVER IN THE H I COLUMN DENSITY DISTRIBUTION

    International Nuclear Information System (INIS)

    Erkal, Denis; Gnedin, Nickolay Y.; Kravtsov, Andrey V.

    2012-01-01

    We study the high column density regime of the H I column density distribution function and argue that there are two distinct features: a turnover at N H I ≈ 10 21 cm –2 , which is present at both z = 0 and z ≈ 3, and a lack of systems above N H I ≈ 10 22 cm –2 at z = 0. Using observations of the column density distribution, we argue that the H I-H 2 transition does not cause the turnover at N H I ≈ 10 21 cm –2 but can plausibly explain the turnover at N H I ∼> 10 22 cm –2 . We compute the H I column density distribution of individual galaxies in the THINGS sample and show that the turnover column density depends only weakly on metallicity. Furthermore, we show that the column density distribution of galaxies, corrected for inclination, is insensitive to the resolution of the H I map or to averaging in radial shells. Our results indicate that the similarity of H I column density distributions at z = 3 and 0 is due to the similarity of the maximum H I surface densities of high-z and low-z disks, set presumably by universal processes that shape properties of the gaseous disks of galaxies. Using fully cosmological simulations, we explore other candidate physical mechanisms that could produce a turnover in the column density distribution. We show that while turbulence within giant molecular clouds cannot affect the damped Lyα column density distribution, stellar feedback can affect it significantly if the feedback is sufficiently effective in removing gas from the central 2-3 kpc of high-redshift galaxies. Finally, we argue that it is meaningful to compare column densities averaged over ∼ kpc scales with those estimated from quasar spectra that probe sub-pc scales due to the steep power spectrum of H I column density fluctuations observed in nearby galaxies.

  10. Electron cooling of highly charged ions in penning traps; Elektronenkuehlung hochgeladener Ionen in Penningfallen

    Energy Technology Data Exchange (ETDEWEB)

    Moellers, B.

    2007-02-08

    For many high precision experiments with highly charged ions in ion traps it is necessary to work with low energy ions. One possibility to slow ions down to a very low energy in a trap is electron cooling, a method, which is already successfully used in storage rings to produce ion beams with high phase space density. Fast ions and a cold electron plasma are inserted into a Penning trap. The ions lose their energy due to Coulomb interaction with the electrons while they cross the plasma, the electrons are heated. The cooling time is the time, which is needed to cool an ion from a given initial energy to a low final energy. To calculate cooling times it is necessary to solve coupled differential equations for the ion energy and electron temperature. In a Penning trap the strong external magnetic field constitutes a theoretical challenge, as it influences the energy loss of the ions in an electron plasma, which can no longer be calculated analytically. In former estimates of cooling times this influence is neglected. But simulations show a dramatic decrease of the energy loss in the presence of a strong magnetic field, so it is necessary to investigate the effect of the magnetic field on the cooling times. This work presents a model to calculate cooling times, which includes both the magnetic field and the trap geometry. In a first step a simplified model without the external trap potential is developed. The energy loss of the ions in the magnetized electron plasma is calculated by an analytic approximation, which requires a numerical solution of integrals. With this model the dependence of the cooling time on different parameters like electron and ion density, magnetic field and the angle between ion velocity and magnetic field is studied for fully ionized uranium. In addition the influence of the electron heating is discussed. Another important topic in this context is the recombination between ions and electrons. The simplified model for cooling times allows to

  11. Total binding energy of heavy positive ions including density treatment of Darwin and Breit corrections

    International Nuclear Information System (INIS)

    Hill, S.H.; Grout, P.J.; March, N.H.

    1987-01-01

    Previous work on the relativistic Thomas-Fermi treatment of total energies of neutral atoms is first generalised to heavy positive ions. To facilitate quantitative contact with the numerical predictions of Dirac-Fock theory, Darwin and Breit corrections are expressed in terms of electron density, and computed using input again from relativistic Thomas-Fermi theory. These corrections significantly improve the agreement between the two seemingly very different theories. (author)

  12. High Energy Density Capacitors, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Capacitor size and reliability are often limiting factors in pulse power, high speed switching, and power management and distribution (PMAD) systems. T/J...

  13. High ion charge states in a high-current, short-pulse, vacuum ARC ion sources

    International Nuclear Information System (INIS)

    Anders, A.; Brown, I.; MacGill, R.; Dickinson, M.

    1996-01-01

    Ions of the cathode material are formed at vacuum arc cathode spots and extracted by a grid system. The ion charge states (typically 1-4) depend on the cathode material and only little on the discharge current as long as the current is low. Here the authors report on experiments with short pulses (several μs) and high currents (several kA); this regime of operation is thus approaching a more vacuum spark-like regime. Mean ion charge states of up to 6.2 for tungsten and 3.7 for titanium have been measured, with the corresponding maximum charge states of up to 8+ and 6+, respectively. The results are discussed in terms of Saha calculations and freezing of the charge state distribution

  14. High ion charge states in a high-current, short-pulse, vacuum arc ion source

    International Nuclear Information System (INIS)

    Anders, A.; Brown, I.; MacGill, R.; Dickinson, M.

    1995-09-01

    Ions of the cathode material are formed at vacuum arc cathode spots and extracted by a grid system. The ion charge states (typically 1--4) depend on the cathode material and only little on the discharge current as long as the current is low. Here the authors report on experiments with short pulses (several micros) and high currents (several kA); this regime of operation is thus approaching a more vacuum spark-like regime. Mean ion charge states of up to 6.2 for tungsten and 3.7 for titanium have been measured, with the corresponding maximum charge states of up to 8+ and 6+, respectively. The results are discussed in terms of Saha calculations and freezing of the charge state distribution

  15. DETERMINATION OF STRONTIUM IONS IN WATERS WITH A HIGH CONTENT OF SODIUM IONS

    Directory of Open Access Journals (Sweden)

    Tatiana Mitina

    2015-06-01

    Full Text Available This paper reports on the influence of sodium ions on experimental determination of strontium ions concentration in waters with a high content of sodium ions by using emission flame photometry and atomic absorption spectroscopy. For the method of emission flame photometry it was shown that at a wavelength of 460.7 nm (spectral emission line of strontium the emission is linearly dependent on the concentration of sodium ions. The greatest impact of high concentrations of sodium ions on the result of determination the strontium ions concentration has been registered at low levels of strontium. The influence of nitric acid on the results is also discussed. In the case of using atomic absorption spectroscopy method no influence of sodium ions and nitric acid on the results of determination the strontium ions concentration was revealed. The metrological characteristics of both methods are evaluated.

  16. High-density carbon ablator ignition path with low-density gas-filled rugby hohlraum

    International Nuclear Information System (INIS)

    Amendt, Peter; Ho, Darwin D.; Jones, Ogden S.

    2015-01-01

    A recent low gas-fill density (0.6 mg/cc 4 He) cylindrical hohlraum experiment on the National Ignition Facility has shown high laser-coupling efficiency (>96%), reduced phenomenological laser drive corrections, and improved high-density carbon capsule implosion symmetry [Jones et al., Bull. Am. Phys. Soc. 59(15), 66 (2014)]. In this Letter, an ignition design using a large rugby-shaped hohlraum [Amendt et al., Phys. Plasmas 21, 112703 (2014)] for high energetics efficiency and symmetry control with the same low gas-fill density (0.6 mg/cc 4 He) is developed as a potentially robust platform for demonstrating thermonuclear burn. The companion high-density carbon capsule for this hohlraum design is driven by an adiabat-shaped [Betti et al., Phys. Plasmas 9, 2277 (2002)] 4-shock drive profile for robust high gain (>10) 1-D ignition performance and large margin to 2-D perturbation growth

  17. High-density carbon ablator ignition path with low-density gas-filled rugby hohlraum

    Science.gov (United States)

    Amendt, Peter; Ho, Darwin D.; Jones, Ogden S.

    2015-04-01

    A recent low gas-fill density (0.6 mg/cc 4He) cylindrical hohlraum experiment on the National Ignition Facility has shown high laser-coupling efficiency (>96%), reduced phenomenological laser drive corrections, and improved high-density carbon capsule implosion symmetry [Jones et al., Bull. Am. Phys. Soc. 59(15), 66 (2014)]. In this Letter, an ignition design using a large rugby-shaped hohlraum [Amendt et al., Phys. Plasmas 21, 112703 (2014)] for high energetics efficiency and symmetry control with the same low gas-fill density (0.6 mg/cc 4He) is developed as a potentially robust platform for demonstrating thermonuclear burn. The companion high-density carbon capsule for this hohlraum design is driven by an adiabat-shaped [Betti et al., Phys. Plasmas 9, 2277 (2002)] 4-shock drive profile for robust high gain (>10) 1-D ignition performance and large margin to 2-D perturbation growth.

  18. High-density carbon ablator ignition path with low-density gas-filled rugby hohlraum

    Energy Technology Data Exchange (ETDEWEB)

    Amendt, Peter; Ho, Darwin D.; Jones, Ogden S. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2015-04-15

    A recent low gas-fill density (0.6 mg/cc {sup 4}He) cylindrical hohlraum experiment on the National Ignition Facility has shown high laser-coupling efficiency (>96%), reduced phenomenological laser drive corrections, and improved high-density carbon capsule implosion symmetry [Jones et al., Bull. Am. Phys. Soc. 59(15), 66 (2014)]. In this Letter, an ignition design using a large rugby-shaped hohlraum [Amendt et al., Phys. Plasmas 21, 112703 (2014)] for high energetics efficiency and symmetry control with the same low gas-fill density (0.6 mg/cc {sup 4}He) is developed as a potentially robust platform for demonstrating thermonuclear burn. The companion high-density carbon capsule for this hohlraum design is driven by an adiabat-shaped [Betti et al., Phys. Plasmas 9, 2277 (2002)] 4-shock drive profile for robust high gain (>10) 1-D ignition performance and large margin to 2-D perturbation growth.

  19. Spontaneous magnetization in high-density quark matter

    DEFF Research Database (Denmark)

    Tsue, Yasuhiko; da Providência, João; Providência, Constanca

    2015-01-01

    It is shown that spontaneous magnetization occurs due to the anomalous magnetic moments of quarks in high-density quark matter under the tensor-type four-point interaction. The spin polarized condensate for each flavor of quark appears at high baryon density, which leads to the spontaneous magnet...

  20. Quantum Phenomena in High Energy Density Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, Margaret [Univ. of Colorado, Boulder, CO (United States); Kapteyn, Henry [Univ. of Colorado, Boulder, CO (United States)

    2017-05-10

    The possibility of implementing efficient (phase matched) HHG upconversion of deep- UV lasers in multiply-ionized plasmas, with potentially unprecedented conversion efficiency is a fascinating prospect. HHG results from the extreme nonlinear response of matter to intense laser light:high harmonics are radiated as a result of a quantum coherent electron recollision process that occurs during laser field ionization of an atom. Under current support from this grant in work published in Science in 2015, we discovered a new regime of bright HHG in highly-ionized plasmas driven by intense UV lasers, that generates bright harmonics to photon energies >280eV

  1. Ion channel density regulates switches between regular and fast spiking in soma but not in axons.

    Directory of Open Access Journals (Sweden)

    Hugo Zeberg

    2010-04-01

    Full Text Available The threshold firing frequency of a neuron is a characterizing feature of its dynamical behaviour, in turn determining its role in the oscillatory activity of the brain. Two main types of dynamics have been identified in brain neurons. Type 1 dynamics (regular spiking shows a continuous relationship between frequency and stimulation current (f-I(stim and, thus, an arbitrarily low frequency at threshold current; Type 2 (fast spiking shows a discontinuous f-I(stim relationship and a minimum threshold frequency. In a previous study of a hippocampal neuron model, we demonstrated that its dynamics could be of both Type 1 and Type 2, depending on ion channel density. In the present study we analyse the effect of varying channel density on threshold firing frequency on two well-studied axon membranes, namely the frog myelinated axon and the squid giant axon. Moreover, we analyse the hippocampal neuron model in more detail. The models are all based on voltage-clamp studies, thus comprising experimentally measurable parameters. The choice of analysing effects of channel density modifications is due to their physiological and pharmacological relevance. We show, using bifurcation analysis, that both axon models display exclusively Type 2 dynamics, independently of ion channel density. Nevertheless, both models have a region in the channel-density plane characterized by an N-shaped steady-state current-voltage relationship (a prerequisite for Type 1 dynamics and associated with this type of dynamics in the hippocampal model. In summary, our results suggest that the hippocampal soma and the two axon membranes represent two distinct kinds of membranes; membranes with a channel-density dependent switching between Type 1 and 2 dynamics, and membranes with a channel-density independent dynamics. The difference between the two membrane types suggests functional differences, compatible with a more flexible role of the soma membrane than that of the axon membrane.

  2. Ion source techniques for high-speed processing of material surface by ion beams

    International Nuclear Information System (INIS)

    Ishikawa, Junzo

    1990-01-01

    The present paper discusses some key or candidate techniques for future ion source development and such ion sources developed by the author. Several types of microwave ion sources for producing low charge state ions have been developed in Japan. When a microwave plasma cathode developed by the author is adapted to a Kaufman type ion source, the electron emission currents are found to be 2.5 A for argon gas and 0.5-0.9 A for oxygen gas. An alternative ionization method for metal atoms is strongly required for high-speed processing of material surface by metal-ion beams. Detailed discussion is made of collisional ionization of vaporized atoms, and negative-ion production (secondary negative-ion emission by sputtering). An impregnated electrode type liquid-metal ion source developed by the author, which has a porous tip structure, is described. The negative-ion production efficiency is quite high. The report also presents a neutral and ionized alkaline-metal bombardment type heavy negative-ion source, which consists of a cesium plasma ion source, suppressor, target electrode, negative-ion extraction electrode, and einzel lens. (N.K.)

  3. Upgraded millimeter-wave interferometer for measuring the electron density during the beam extraction in the negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Tokuzawa, T., E-mail: tokuzawa@nifs.ac.jp; Kisaki, M.; Nagaoka, K.; Ito, Y.; Ikeda, K.; Nakano, H. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Tsumori, K.; Osakabe, M.; Takeiri, Y. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); The Graduate University for Advanced Studies, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Kaneko, O. [National Institutes of Natural Sciences, 4-3-13 Toranomon, Minato-ku, Tokyo 105-0001 (Japan)

    2016-11-15

    The upgraded millimeter-wave interferometer with the frequency of 70 GHz is installed on a large-scaled negative ion source. Measurable line-averaged electron density is from 2 × 10{sup 15} to 3 × 10{sup 18} m{sup −3} in front of the plasma grid. Several improvements such as the change to shorter wavelength probing with low noise, the installation of special ordered horn antenna, the signal modulation for a high accuracy digital phase detection, the insertion of insulator, and so on, are carried out for the measurement during the beam extraction by applying high voltage. The line-averaged electron density is successfully measured and it is found that it increases linearly with the arc power and drops suddenly at the beam extraction.

  4. Properties of Laser-Produced Highly Charged Heavy Ions for Direct Injection Scheme

    CERN Document Server

    Sakakibara, Kazuhiko; Hayashizaki, Noriyosu; Ito, Taku; Kashiwagi, Hirotsugu; Okamura, Masahiro

    2005-01-01

    To accelerate highly charged intense ion beam, we have developed the Direct Plasma Injection Scheme (DPIS) with laser ion source. In this scheme an ion beam from a laser ion source is injected directly to a RFQ linac without a low energy beam transport (LEBT) and the beam loss in the LEBT can be avoided. We achieved high current acceleration of carbon ions (60mA) by DPIS with the high current optimized RFQ. As the next setp we will use heavier elements like Ag, Pb, Al and Cu as target in LIS (using CO2, Nd-YAG or other laser) for DPIS and will examine properties of laser-produced plasma (the relationship of between charge state and laser power density, the current dependence of the distance from the target, etc).

  5. Filter device for high density aerozol

    International Nuclear Information System (INIS)

    Karasawa, Hidetoshi; Endo, Masao; Utamura, Motoaki; Tozuka, Fumio; Tate, Hitoshi.

    1991-01-01

    In a reactor, filters for capturing aerozol particles at high concentration have such a structure that a great number of fine pores are formed. Aerozols are introduced to a filter portion from the place remote from a first inlet. Cloggings are caused successively from the places remote from the inlet. Even if the clogging should occur, since there are many pores, the performance of filters is not deteriorated. Further, the filter has a multi-layered structure. With such a constitution, if the filter at a first stage is clogged to increase the pressure, a partitioning plate is opened and fluids are introduced into a second filter. This is conducted successively to suppress the deterioration of the performance of the filter. In view of the above, even if cloggings should occur, the filter performance is not deteriorated and, accordingly, reactor container ventilation can be conducted at high reliability upon occurrence of accidents. (T.M.)

  6. The creation of high energy densities with antimatter beams

    International Nuclear Information System (INIS)

    Gibbs, W.R.; Kruk, J.W.; Rice Univ., Houston, TX

    1989-01-01

    The use of antiprotons (and antideuterons) for the study of the behavior of nuclear matter at high energy density is considered. It is shown that high temperatures and high energy densities can be achieved for small volumes. Also investigated is the strangeness production in antimatter annihilation. It is found that the high rate of Lambda production seen in a recent experiment is easily understood. The Lambda and K-short rapidity distributions are also reproduced by the model considered. 11 refs., 6 figs

  7. High-current negative hydrogen ion beam production in a cesium-injected multicusp source

    International Nuclear Information System (INIS)

    Takeiri, Y.; Tsumori, K.; Kaneko, O.

    1997-01-01

    A high-current negative hydrogen ion source has been developed, where 16.2 A of the H - current was obtained with a current density of 31 mA/cm 2 . The ion source is a multicusp source with a magnetic filter for negative ion production, and cesium vapor is injected into the arc chamber, leading to enhancement of the negative ion yields. The cesium-injection effects are discussed, based on the experimental observations. Although the surface production of the negative ions on the cesium-covered plasma grid is thought to be a dominant mechanism of the H - current enhancement, the cesium effects in the plasma volume, such as the cesium ionization and the electron cooling, are observed, and could contribute to the improved operation of the negative ion source. (author)

  8. High current transport experiment for heavy ion inertial fusion

    Directory of Open Access Journals (Sweden)

    L. R. Prost

    2005-02-01

    Full Text Available The High Current Experiment at Lawrence Berkeley National Laboratory is part of the U.S. program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density ∼0.2  μC/m over long pulse durations (4  μs in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo, and electron and gas cloud effects. We present the results for a coasting 1 MeV K^{+} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius for which the transverse phase space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor (≈80% is achieved with acceptable emittance growth and beam loss, even though the initial beam distribution is not ideal (but the emittance is low nor in thermal equilibrium. We achieved good envelope control, and rematching may only be needed every ten lattice periods (at 80% fill factor in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  9. Spectroscopic investigations of high-energy-density\

    Czech Academy of Sciences Publication Activity Database

    Civiš, Martin; Ferus, Martin; Knížek, Antonín; Kubelík, Petr; Kamas, Michal; Španěl, Patrik; Dryahina, Kseniya; Shestivska, Violetta; Juha, Libor; Skřehot, P.; Laitl, V.; Civiš, Svatopluk

    2016-01-01

    Roč. 18, č. 39 (2016), s. 27317-27325 ISSN 1463-9076 R&D Projects: GA ČR(CZ) GA14-12010S; GA MŠk LG15013; GA MŠk(CZ) LM2015083 Grant - others:Akademie věd - GA AV ČR(CZ) R200401521 Institutional support: RVO:61388955 ; RVO:68378271 Keywords : HIGH-POWER LASER * INDUCED DIELECTRIC-BREAKDOWN * EARTHS EARLY ATMOSPHERE Subject RIV: CF - Physical ; Theoretical Chemistry; BL - Plasma and Gas Discharge Physics (FZU-D) Impact factor: 4.123, year: 2016

  10. Electron-Ion Dynamics with Time-Dependent Density Functional Theory: Towards Predictive Solar Cell Modeling: Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Maitra, Neepa [Hunter College City University of New York, New York, NY (United States)

    2016-07-14

    This project investigates the accuracy of currently-used functionals in time-dependent density functional theory, which is today routinely used to predict and design materials and computationally model processes in solar energy conversion. The rigorously-based electron-ion dynamics method developed here sheds light on traditional methods and overcomes challenges those methods have. The fundamental research undertaken here is important for building reliable and practical methods for materials discovery. The ultimate goal is to use these tools for the computational design of new materials for solar cell devices of high efficiency.

  11. Ultra-high density aligned Carbon-nanotube with controled nano-morphology for supercapacitors

    Science.gov (United States)

    Ghaffari, Mehdi; Zhao, Ran; Liu, Yang; Zhou, Yue; Cheng, Jiping; Guzman de Villoria, Roberto; Wardle, B. L.; Zhang, Q. M.

    2012-02-01

    Recent advances in fabricating controlled-morphology vertically aligned carbon nanotubes (VA-CNTs) with ultrahigh volume fractioncreate unique opportunities for developing unconventional supercapacitors with ultra-high energy density, power density, and long charge/discharge cycle life.Continuous paths through inter-VA-CNT channels allow fast ion transport, and high electrical conduction of the aligned CNTs in the composite electrodes lead to fast discharge speed. We investigate the charge-discharge characteristics of VA-CNTs with >20 vol% of CNT and ionic liquids as electrolytes. By employing both the electric and electromechanical spectroscopes, as well as nanostructured materials characterization, the ion transport and storage behaviors in porous electrodes are studied. The results suggest pathways for optimizing the electrode morphology in supercapacitorsusing ultra-high volume fraction VA-CNTs to further enhance performance.

  12. Concept for high-charge-state ion induction accelerators

    International Nuclear Information System (INIS)

    Logan, B.G.; Perry, M.D.; Caporaso, G.J.

    1996-01-01

    This work describes a particular concept for ion induction linac accelerators using high-charge-state ions produced by an intense, short pulse laser, and compares the costs of a modular driver system producing 6.5 MJ for a variety of ion masses and charge states using a simple but consistent cost model

  13. Self-consistent-field calculations of atoms and ions using a modified local-density approximation

    International Nuclear Information System (INIS)

    Liberman, D.A.; Albritton, J.R.; Wilson, B.G.; Alley, W.E.

    1994-01-01

    Local-density-approximation calculations of atomic structure are useful for the description of atoms and ions in plasmas. The large number of different atomic configurations that exist in typical plasmas leads one to consider the expression of total energies in terms of a Taylor series in the orbital occupation numbers. Two schemes for computing the second derivative Taylor-series coefficients are given; the second, and better one, uses the linear response method developed by Zangwill and Soven [Phys. Rev. A 21, 1561 (1980)] for the calculation of optical response in atoms. A defect in the local-density approximation causes some second derivatives involving Rydberg orbitals to be infinite. This is corrected by using a modified local-density approximation that had previously been proposed [Phys. Rev. B 2, 244 (1970)

  14. Magnetic fusion with high energy self-colliding ion beams

    International Nuclear Information System (INIS)

    Rostoker, N.; Wessel, F.; Maglich, B.; Fisher, A.

    1992-06-01

    Field-reversed configurations of energetic large orbit ions with neutralizing electrons have been proposed as the basis of a fusion reactor. Vlasov equilibria consisting of a ring or an annulus have been investigated. A stability analysis has been carried out for a long thin layer of energetic ions in a low density background plasma. There is a growing body of experimental evidence from tokamaks that energetic ions slow down and diffuse in accordance with classical theory in the presence of large non-thermal fluctuations and anomalous transport of low energy (10 keV) ions. Provided that major instabilities are under control, it seems likely that the design of a reactor featuring energetic self-colliding ion beams can be based on classical theory. In this case a confinement system that is much better than a tokamak is possible. Several methods are described for creating field reversed configurations with intense neutralized ion beams

  15. Magnetic fusion with high energy self-colliding ion beams

    International Nuclear Information System (INIS)

    Restoker, N.; Wessel, F.; Maglich, B.; Fisher, A.

    1993-01-01

    Field-reversed configurations of energetic large orbit ions with neutralizing electrons have been proposed as the basis of a fusion reactor. Vlasov equilibria consisting of a ring or an annulus have been investigated. A stability analysis has been carried out for a long thin layer of energetic ions in a low density background plasma. There is a growing body of experimental evidence from tokamaks that energetic ions slow down and diffuse in accordance with classical theory in the presence of large non-thermal fluctuations and anomalous transport of low energy (10 keV) ions. Provided that major instabilities are under control, it seems likely that the design of a reactor featuring energetic self-colliding ion beams can be based on classical theory. In this case a confinement system that is much better than a tokamak is possible. Several methods are described for creating field reversed configurations with intense neutralized ion beams

  16. Extreme ultraviolet spectroscopy of highly charged argon ions at the Berlin EBIT

    International Nuclear Information System (INIS)

    Biedermann, C; Radtke, R; Fussmann, G; Allen, F I

    2007-01-01

    Extreme ultraviolet radiation from highly charged argon was investigated at the Berlin Electron Beam Ion Trap with a 2 m grazing incidence spectrometer. Lines in the wavelength range 150 to 660 A originating from C-like Ar 12+ to Li-like Ar 15+ ions have been identified and are compared with database information from solar line lists and predictions. Line ratios for the observed resonance, intercombination and forbidden lines offer important diagnostic capabilities for low density, hot plasmas

  17. Lexical Density Of English Reading Texts For Senior High School

    OpenAIRE

    Nesia, Bersyebah Herljimsi; Ginting, Siti Aisah

    2014-01-01

    This study deals with the lexical density especially the lexical items of English reading texts in the textbook for senior high school. The objectives of the study are to find out the lexical density especially the lexical items which formed in the reading texts of Look Ahead textbook and the type of genre which has the highest lexical density of the reading texts. This study was conducted by descriptive method with qualitative approach. The data of this research were the English reading text...

  18. High Energy Ion Acceleration by Extreme Laser Radiation Pressure

    Science.gov (United States)

    2017-03-14

    published in the internationally leading journal Physical Review Letters. We continued to progress this pionee 15.  SUBJECT TERMS ion therapy, heavy ion ...Thomson parabola spectrometer: To separate and provide a measurement of the charge -to-mass ratio and energy spectrum of the different ion species...AFRL-AFOSR-UK-TR-2017-0015 High energy ion acceleration by extreme laser radiation pressure Paul McKenna UNIVERSITY OF STRATHCLYDE VIZ ROYAL COLLEGE

  19. Quantum electrodynamical effects in heavy highly-charged ions

    International Nuclear Information System (INIS)

    Yerokhin, V.A.; Artemyev, A.N.; Indelicato, P.; Shabaev, V.M.

    2003-01-01

    The present status of theoretical calculations of QED effects in highly charged ions is reviewed for several important cases: the Lamb shift in heavy H-like ions, the 2p 1/2 -2s transition energy in heavy Li-like ions, and the bound-electron g factor in H-like ions. Theoretical predictions are compared with experimental results. Special attention is paid to the discussion of uncertainties of theoretical predictions

  20. Super TOF secondary ion mass spectroscopy using very highly charged primary ions up to Th70+

    International Nuclear Information System (INIS)

    Briere, M.A.; Schenkel, T.; Schneider, D.

    1995-01-01

    The LLNL Electron Beam Ion Trap (EBIT) has made low emittance beams of slow highly charged ions available for ion-solid interaction studies. Such interactions feature the dominance of electronic over collisional effects, and the shock waves generated by the ionized target atoms can desorb large numbers of large molecular species from the surface. This paper presents the first systematic study of the sputtering process due to the incidence of slow very highly charged ions; Th 70+ ions are extracted from EBIT at 7 keV * q and directed onto thin SiO 2 films on Si. Results suggest secondary ion yields of up to 25 per incident ion for Th 70+ (secondary ion yield is increased over that for singly or moderately charged ions). Correlations of the negative, positive, and negative cluster ion yields show promise for application of highly charged ion induced sputtering for enhanced sensitivity and quantitative (absolute) SIMS analysis of deep submicron scale surface layers and polymeric and biomolecular material analysis

  1. Modified Korteweg-deVries soliton evolution at critical density of negative ions in an inhomogeneous magnetized cold plasma

    International Nuclear Information System (INIS)

    Singh, Dhananjay K.; Malik, Hitendra K.

    2007-01-01

    Soliton propagation at critical density of negative ions is studied for weakly inhomogeneous magnetized cold plasma having positive ions, negative ions, and electrons. A general phase velocity relation is obtained and possible modes are studied for different cases involving different constituents of the plasma. Two types of modes (fast and slow) are found to propagate for the equal mass of the positive and negative ions. However, a limit on the obliqueness of magnetic field is obtained for the propagation of slow mode. For both types of modes, a variable coefficient modified Korteweg-deVries equation with an additional term arisen due to the density gradient is realized, which admits solutions for compressive solitons and rarefactive solitons of the same amplitudes at critical negative ion density. The propagation characteristics of these solitons are studied under the effect of densities of ions, magnetic field, and its obliqueness. The amplitudes of fast and slow wave solitons show their opposite behavior with the negative ion concentration, which is consistent with the variation of phase velocities with the negative ion density

  2. Apparatus and method for generating high density pulses of electrons

    International Nuclear Information System (INIS)

    Lee, C.; Oettinger, P.E.

    1981-01-01

    An apparatus and method are described for the production of high density pulses of electrons using a laser energized emitter. Caesium atoms from a low pressure vapour atmosphere are absorbed on and migrate from a metallic target rapidly heated by a laser to a high temperature. Due to this heating time being short compared with the residence time of the caesium atoms adsorbed on the target surface, copious electrons are emitted which form a high current density pulse. (U.K.)

  3. Low density, variation in sintered density and high nitrogen in uranium dioxide

    International Nuclear Information System (INIS)

    Balakrishna, Palanki; Murty, B.N.; Anuradha, M.; Nageshwara Rao, P.; Jayaraj, R.N.; Ganguly, C.

    2000-01-01

    Low sintered density and density variation in sintered UO 2 were found to have been caused by non uniformity in the granule feed characteristics to the compacting press. The nitrogen impurity content of sintered UO 2 was found to be sintering furnace related and associated with low sintered density pellets. The problems of low density, variation in sintered density and high nitrogen could be solved by the replacement of the prevailing four punch precompaction by a single punch process; by the introduction of a vibro-sieve for the separation of fine particles from the press feed granules; by innovation in the powder feed shoe design for simultaneous and uniform dispensing of powder in all the die holes; by increasing the final compaction pressure and by modifying the gas flows and preheat temperature in the sintering furnace. (author)

  4. Properties of matter at ultra-high densities

    International Nuclear Information System (INIS)

    Banerjee, B.; Chitre, S.M.

    1975-01-01

    The recent discovery of pulsars and their subsequent identification with neutron stars has given a great impetus to the study of the behaviour of matter at ultra high densities. The object of these studies is to calculate the equation of state as a function of density. In this paper, the properties of electrically neutral, cold (T=0) matter at unusually high densities has been reviewed. The physics of the equation of state of such matter divides quite naturally in four density ranges. (i) At the very lowest densities the state of minimum energy is a lattice of 56 Fe atoms. This state persists upto 10 7 g/cm 3 . (ii) In the next density region the nuclei at the lattice sites become neutron rich because the high electron Fermi energy makes inverse beta decay possible. (iii) At a density 4.3 x 10 11 the nuclei become so neutron rich that the neutrons start 'dripping' out of the nuclei and form a gas. This density range is characterised by large, neutron-rich nuclei immersed in a neutron gas. (iv) At a density 2.4 x 10 14 g/cm 3 , the nuclei disappear and a fluid of uniform neutron matter with a small percentage of protons and electrons results. The above four density ranges have been discussed in detail as the equation of state is now well established upto the nuclear density 3 x 10 14 g/cm 3 . The problems of extending the equation of state beyond this density are also touched upon. (author)

  5. Heavy ion reactions at high energies

    International Nuclear Information System (INIS)

    Jakobsson, Bo.

    1977-01-01

    A review on heavy ion experiments at energies >0.1GeV/nucleon is presented. Reaction cross-sections, isotope production cross-sections and pion production in nucleus-nucleus collisions are discussed. Some recent models for heavy ion reactions like the abrasion-ablation model, the fireball model and the different shock-wave models are also presented

  6. 7th high energy heavy ion study

    International Nuclear Information System (INIS)

    Bock, R.; Gutbrod, H.H.; Stock, R.

    1985-03-01

    These proceedings contain the articles presented at the named conference. They deal with relativistic heavy ion reactions, the expansion and freeze-out of nuclear matter, anomalon experiments, and multifragmentation and particle correlations in heavy ion reactions. See hints under the relevant topics. (HSI)

  7. High Precision Beam Diagnostics for Ion Thrusters

    NARCIS (Netherlands)

    Van Reijen, B.; Koch, N.; Lazurenko, A.; Weis, S.; Schirra, M.; Genovese, A.; Haderspeck, J.; Gill, E.K.A.

    2011-01-01

    The Thales diagnostic equipment for ion beam characterization consists of a gridded and single orifice retarding potential analyzer (RPA) and an energy selective mass spectrometer (ESMS). During the development phase of these sensors considerable effort was put into the removal of ion optical

  8. Performance Limitations in High-Energy Ion Colliders

    CERN Document Server

    Fischer, Wolfram

    2005-01-01

    High-energy ion colliders (hadron colliders operating with species other than protons) are premier research tools for nuclear physics. The collision energy and high luminosity are important design and operations considerations. However, the experiments also expect flexibility with frequent changes in the collision energy, lattice configuration, and ion species, including asymmetric collisions. For the creation, acceleration, and storage of bright intense ion beams, attention must be paid to space charge, charge exchange, and intra-beam scattering effects. The latter leads to luminosity lifetimes of only a few hours for heavy ions. Ultimately cooling at full energy is needed to overcome this effect. Currently, the Relativistic Heavy Ion Collider at BNL is the only operating high-energy ion collider. The Large Hadron Collider, under construction at CERN, will also run with heavy ions.

  9. Event-by-event gluon multiplicity, energy density, and eccentricities in ultrarelativistic heavy-ion collisions

    Science.gov (United States)

    Schenke, Björn; Tribedy, Prithwish; Venugopalan, Raju

    2012-09-01

    The event-by-event multiplicity distribution, the energy densities and energy density weighted eccentricity moments ɛn (up to n=6) at early times in heavy-ion collisions at both the BNL Relativistic Heavy Ion Collider (RHIC) (s=200GeV) and the CERN Large Hardron Collider (LHC) (s=2.76TeV) are computed in the IP-Glasma model. This framework combines the impact parameter dependent saturation model (IP-Sat) for nucleon parton distributions (constrained by HERA deeply inelastic scattering data) with an event-by-event classical Yang-Mills description of early-time gluon fields in heavy-ion collisions. The model produces multiplicity distributions that are convolutions of negative binomial distributions without further assumptions or parameters. In the limit of large dense systems, the n-particle gluon distribution predicted by the Glasma-flux tube model is demonstrated to be nonperturbatively robust. In the general case, the effect of additional geometrical fluctuations is quantified. The eccentricity moments are compared to the MC-KLN model; a noteworthy feature is that fluctuation dominated odd moments are consistently larger than in the MC-KLN model.

  10. BCS Theory of Hadronic Matter at High Densities

    DEFF Research Database (Denmark)

    Bohr, Henrik; Panda, Prafulla K.; Providencia, Constanca

    2012-01-01

    The equilibrium between the so-called 2SC and CFL phases of strange quark matter at high densities is investigated in the framework of a simple schematic model of the NJL type. Equal densities are assumed for quarks u, d and s. The 2SC phase is here described by a color-flavor symmetric state, in...

  11. Ge nano-layer fabricated by high-fluence low-energy ion implantation

    International Nuclear Information System (INIS)

    Lu Tiecheng; Dun Shaobo; Hu Qiang; Zhang Songbao; An Zhu; Duan Yanmin; Zhu Sha; Wei Qiangmin; Wang Lumin

    2006-01-01

    A Ge nano-layer embedded in the surface layer of an amorphous SiO 2 film was fabricated by high-fluence low-energy ion implantation. The component, phase, nano-structure and luminescence properties of the nano-layer were studied by means of Rutherford backscattering, glancing incident X-ray diffraction, laser Raman scattering, transmission electron microscopy and photoluminescence. The relation between nano-particle characteristics and ion fluence was also studied. The results indicate that nano-crystalline Ge and nano-amorphous Ge particles coexist in the nano-layer and the ratio of nano-crystalline Ge to nano-particle Ge increases with increasing ion fluence. The intensity of photoluminescence from the nano-layer increases with increasing ion fluence also. Prepared with certain ion fluences, high-density nano-layers composed of uniform-sized nano-particles can be observed

  12. Phenomenology of high density disruptions in the TFTR tokamak

    International Nuclear Information System (INIS)

    Fredrickson, E.D.; McGuire, K.M.; Bell, M.G.

    1993-01-01

    Studies of high density disruptions on TFTR, including a comparison of minor and major disruptions at high density, provide important new information regarding the nature of the disruption mechanism. Further, for the first time, an (m,n)=(1,1) 'cold bubble' precursor to high density disruptions has been experimentally observed in the electron temperature profile. The precursor to major disruptions resembles the 'vacuum bubble' model of disruptions first proposed by B.B. Kadomtsev and O.P. Pogutse (Sov. Phys. - JETP 38 (1974) 283). (author). Letter-to-the-editor. 25 refs, 3 figs

  13. High-density-plasma diagnostics in magnetic-confinement fusion

    International Nuclear Information System (INIS)

    Jahoda, F.C.

    1982-01-01

    The lectures will begin by defining high density in the context of magnetic confinement fusion research and listing some alternative reactor concepts, ranging from n/sub e/ approx. 2 x 10 14 cm -3 to several orders of magnitude greater, that offer potential advantages over the main-line, n/sub e/ approx. 1 x 10 14 cm -3 , Tokamak reactor designs. The high density scalings of several major diagnostic techniques, some favorable and some disadvantageous, will be discussed. Special emphasis will be given to interferometric methods, both electronic and photographic, for which integral n/sub e/dl measurements and associated techniques are accessible with low wavelength lasers. Reactor relevant experience from higher density, smaller dimension devices exists. High density implies high β, which implies economies of scale. The specialized features of high β diagnostics will be discussed

  14. Research on high energy density plasmas and applications

    International Nuclear Information System (INIS)

    1999-01-01

    Recently, technologies on lasers, accelerators, and pulse power machines have been significantly advanced and input power density covers the intensity range from 10 10 W/cm 2 to higher than 10 20 W/cm 2 . As the results, high pressure gas and solid targets can be heated up to very high temperature to create hot dense plasmas which have never appeared on the earth. The high energy density plasmas opened up new research fields such as inertial confinement fusion, high brightness X-ray radiation sources, interiors of galactic nucleus,supernova, stars and planets, ultra high pressure condensed matter physics, plasma particle accelerator, X-ray laser, and so on. Furthermore, since these fields are intimately connected with various industrial sciences and technologies, the high energy density plasma is now studied in industries, government institutions, and so on. This special issue of the Journal of Plasma Physics and Nuclear Fusion Research reviews the high energy density plasma science for the comprehensive understanding of such new fields. In May, 1998, the review committee for investigating the present status and the future prospects of high energy density plasma science was established in the Japan Society of Plasma Science and Nuclear Fusion Research. We held three committee meetings to discuss present status and critical issues of research items related to high energy density plasmas. This special issue summarizes the understandings of the committee. This special issue consists of four chapters: They are Chapter 1: Physics important in the high energy density plasmas, Chapter 2: Technologies related to the plasma generation; drivers such as lasers, pulse power machines, particle beams and fabrication of various targets, Chapter 3: Plasma diagnostics important in high energy density plasma experiments, Chapter 4: A variety of applications of high energy density plasmas; X-ray radiation, particle acceleration, inertial confinement fusion, laboratory astrophysics

  15. Ion trapping in the high-energy storage ring HESR

    Energy Technology Data Exchange (ETDEWEB)

    Hinterberger, Frank [Bonn Univ. (Germany). Helmholtz-Institut fuer Strahlen- und Kernphysik

    2011-10-15

    The problem of ion trapping in the high-energy storage ring HESR is studied in the present report. Positive ions are trapped in the negative potential well of the antiproton beam. The ions are produced by the interaction between the antiproton beam and the residual gas. The adverse effects of ion trapping like tune shifts, tune spreads and coherent instabilities are reviewed. The ion production rate by ionization of the residual gas molecules is estimated. The negative potential well and the corresponding electric fields of the antiproton beam are evaluated in order to study the transverse and longitudinal motion of the ions and the accumulation in trapping pockets. The removal of ions can be achieved using clearing electrodes and under certain conditions resonant transverse beam shaking. Diagnostic tools and measurements of trapped ion effects are sketched. (orig.)

  16. Atomic physics of highly charged ions in an electron beam ion trap

    International Nuclear Information System (INIS)

    Marrs, R.E.

    1990-07-01

    Two electron beam ion traps are in use at LLNL for the purpose of studying the properties of very highly charged ions and their interactions with electrons. This paper reviews the operation of the traps and discusses recent experiments in three areas: precision transition energy measurements in the limit of very high ion charge, dielectronic recombination measurements for the He-like isoelectronic sequence, and measurements of x-ray polarization. 22 refs., 11 figs., 1 tab

  17. The neutron/proton ratio of squeezed-out nucleons and the high density behavior of the nuclear symmetry energy

    International Nuclear Information System (INIS)

    Yong Gaochan; Li Baoan; Chen Liewen

    2007-01-01

    Within a transport model it is shown that the neutron/proton ratio of squeezed-out nucleons perpendicular to the reaction plane, especially at high transverse momenta, in heavy-ion reactions induced by high energy neutron-rich nuclei can be a useful tool for studying the high density behavior of the nuclear symmetry energy

  18. Properties of ion temperature gradient and trapped electron modes in tokamak plasmas with inverted density profiles

    Science.gov (United States)

    Du, Huarong; Jhang, Hogun; Hahm, T. S.; Dong, J. Q.; Wang, Z. X.

    2017-12-01

    We perform a numerical study of linear stability of the ion temperature gradient (ITG) mode and the trapped electron mode (TEM) in tokamak plasmas with inverted density profiles. A local gyrokinetic integral equation is applied for this study. From comprehensive parametric scans, we obtain stability diagrams for ITG modes and TEMs in terms of density and temperature gradient scale lengths. The results show that, for the inverted density profile, there exists a normalized threshold temperature gradient above which the ITG mode and the TEM are either separately or simultaneously unstable. The instability threshold of the TEM for the inverted density profile is substantially different from that for normal and flat density profiles. In addition, deviations are found on the ITG threshold from an early analytic theory in sheared slab geometry with the adiabatic electron response [T. S. Hahm and W. M. Tang, Phys. Fluids B 1, 1185 (1989)]. A possible implication of this work on particle transport in pellet fueled tokamak plasmas is discussed.

  19. Formation time of hadrons and density of matter produced in relativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Pisut, J.; Zavada, P.

    1994-06-01

    Densities of interacting hadronic matter produced in Oxygen-Lead and Sulphur-Lead collisions at 200 GeV/nucleon are estimated as a function of the formation time of hadrons. Uncertainties in our knowledge of the critical temperature T c and of the formation time of hadrons τ 0 permit at present three scenarios: an optimistic one (QGP has already been produced in collisions of Oxygen and Sulphur with heavy ions and will be copiously in Lead collisions), a pessimistic one (QGP cannot be produced at 200 GeV/nucleon) and an intermediate one (QGP has not been produced in Oxygen and Sulphur Interactions with heavy ions and will be at best produced only marginally in Pb-collisions). The last option is found to be the most probable. (author)

  20. Calculating the Maximum Density of the Surface Packing of Ions in Ionic Liquids

    Science.gov (United States)

    Kislenko, S. A.; Moroz, Yu. O.; Karu, K.; Ivaništšev, V. B.; Fedorov, M. V.

    2018-05-01

    The maximum density of monolayer packing on a graphene surface is calculated by means of molecular dynamics (MD) for ions of characteristic size and symmetry: 1-butyl-3-methylimidazolium [BMIM]+, tetrabutylammonium [TBA]+, tetrafluoroborate [BF4]-, dicyanamide [DCA]-, and bis(trifluoromethane) sulfonimide [TFSI]-. The characteristic orientations of ions in a closely packed monolayer are found. It is shown that the formation of a closely packed monolayer is possible for [DCA]- and [BF4]- anions only at surface charges that exceed the limit of the electrochemical stability of the corresponding ionic liquids. For the [TBA]+ cation, a monolayer structure can be observed at the charge of nearly 30 μC/cm2 attainable in electrochemical experiment.

  1. Dispersion relations of density fluctuations observed by heavy ion beam probe in the TEXT tokamak

    International Nuclear Information System (INIS)

    Ross, D.W.

    1990-09-01

    Wave numbers as functions of frequency for density fluctuations in the core of the TEXT tokamak are measured in Heavy Ion Beam Probe experiments by analyzing the relative phases of signals originating from nearby points in the plasma. The adjacent points are typically 2 cm apart, with their relative orientation (δr, δθ) depending on position (r,θ). for angular frequencies ω ≤ 10 6 /s the signals are quite coherent, leading to reasonably well-defined ''dispersion relations.'' These do not correspond to known modes of the drift wave type, i.e., ballooning or slab-like electron drift waves or ion temperature gradient modes. The effect of finite sample volume size does not significantly alter this conclusion. 25 refs., 6 figs., 3 tabs

  2. Effect of mix proportion of high density concrete on compressive strength, density and radiation absorption

    International Nuclear Information System (INIS)

    Noor Azreen Masenwat; Mohamad Pauzi Ismail; Suhairy Sani; Ismail Mustapha; Nasharuddin Isa; Mohamad Haniza Mahmud; Mohammad Shahrizan Samsu

    2014-01-01

    To prevent radiation leaks at nuclear reactors, high-density concrete is used as an absorbent material for radiation from spreading into the environment. High-density concrete is a mixture of cement, sand, aggregate (usually high-density minerals) and water. In this research, hematite stone is used because of its mineral density higher than the granite used in conventional concrete mixing. Mix concrete in this study were divided into part 1 and part 2. In part 1, the concrete mixture is designed with the same ratio of 1: 2: 4 but differentiated in terms of water-cement ratio (0.60, 0.65, 0.70, 0.75, 0.80 ). Whereas, in part 2, the concrete mixture is designed to vary the ratio of 1: 1: 2, 1: 1.5: 3, 1: 2: 3, 1: 3: 6, 1: 2: 6 with water-cement ratio (0.7, 0.8, 0.85, 0.9). In each section, the division has also performed in a mixture of sand and fine sand hematite. Then, the physical characteristics of the density and the compressive strength of the mixture of part 1 and part 2 is measured. Comparisons were also made in terms of absorption of radiation by Cs-137 and Co-60 source for each mix. This paper describes and discusses the relationship between the concrete mixture ratio, the relationship with the water-cement ratio, compressive strength, density, different mixture of sand and fine sand hematite. (author)

  3. High-temperature superconductors induced by ion implantation. Final report

    International Nuclear Information System (INIS)

    Greenwald, A.C.; Johnson, E.

    1988-08-01

    High dose oxygen ion implantation (10 to the 17th power ions per sq. cm.) at elevated temperatures (300 C) has been shown to adjust the critical temperature of gamma-Y-Ba-Cu-O and Bi-Ca-Sr-Cu-O materials. These results are in marked contrast to earlier work which showed complete destruction of superconducting properties for similar radiation doses, and marked reduction in superconducting properties at one-tenth this dose in the 1-2-3- compound only. Experiments also showed that the superconducting materials can be patterned into conducting and nonconducting areas without etching by ion implantation, allowing maintenance of planar geometries required for microcircuit fabrication. Experiments on deposition of thin films of high temperature superconductors for use with the ion implantation experiments showed that ion beam sputtering from a single target could achieve the correct stoichiometry. Variations of composition with ion beam energy and angle of sputtered ions were studied

  4. High-voltage scanning ion microscope: Beam optics and design

    Energy Technology Data Exchange (ETDEWEB)

    Magilin, D., E-mail: dmitrymagilin@gmail.com; Ponomarev, A.; Rebrov, V.; Ponomarov, A.

    2015-05-01

    This article is devoted to the conceptual design of a compact high-voltage scanning ion microscope (HVSIM). In an HVSIM design, the ion optical system is based on a high-brightness ion source. Specifically, the ion optical system is divided into two components: an ion injector and a probe-forming system (PFS) that consists of an accelerating tube and a multiplet of quadrupole lenses. The crossover is formed and controlled by the injector, which acts as an object collimator, and is focused on the image plane by the PFS. The ion microprobe has a size of 0.1 μm and an energy of 2 MeV. When the influence of the chromatic and third-order aberrations is theoretically taken into account, the HVSIM forms an ion microprobe.

  5. Large area negative ion source for high voltage neutral beams

    International Nuclear Information System (INIS)

    Poulsen, P.; Hooper, E.B. Jr.

    1979-11-01

    A source of negative deuterium ions in the multi-ampere range is described that is readily extrapolated to reactor size, 10 amp or more of neutral beam, that is of interest in future experiments and reactors. The negative ion source is based upon the double charge exchange process. A beam of positive ions is created and accelerated to an energy at which the attachment process D + M → D - + M + proceeds efficiently. The positive ions are atomically neutralized either in D 2 or in the charge exchange medium M. Atomic species make a second charge exchange collision in the charge target to form D - . For a sufficiently thick target, the beam reaches an equilibrium fraction of negative ions. For reasons of efficiency, the target is typically alkali metal vapor; this experiment uses sodium. The beam of negative ions can be accelerated to high (>200 keV) energy, the electrons stripped from the ions, and a high energy neutral beam formed

  6. High Power Density Power Electronic Converters for Large Wind Turbines

    DEFF Research Database (Denmark)

    Senturk, Osman Selcuk

    . For these VSCs, high power density is required due to limited turbine nacelle space. Also, high reliability is required since maintenance cost of these remotely located wind turbines is quite high and these turbines operate under harsh operating conditions. In order to select a high power density and reliability......In large wind turbines (in MW and multi-MW ranges), which are extensively utilized in wind power plants, full-scale medium voltage (MV) multi-level (ML) voltage source converters (VSCs) are being more preferably employed nowadays for interfacing these wind turbines with electricity grids...... VSC solution for wind turbines, first, the VSC topology and the switch technology to be employed should be specified such that the highest possible power density and reliability are to be attained. Then, this qualitative approach should be complemented with the power density and reliability...

  7. Radiative recombination of highly charged ions: Enhanced rates at low energies

    International Nuclear Information System (INIS)

    Frank, A.; Mueller, A.; Haselbauer, J.; Schennach, S.; Spies, W.; Uwira, O.; Wagner, M.

    1992-01-01

    In a single-pass merged-beams experiment employing a dense cold electron target recombination of highly charged ions is studied. Unexpected high recombination rates are observed at low energies E cm in the electron-ion center-of-mass frame. In particular, theoretical estimates for radiative recombination are dramatically exceeded by the experimental recombination rates at E cm =0 eV for U 28+ and for Au 25+ ions. Considerable rate enhancement is also observed for Ar 15+ . This points to a general phenomenon which has to be interpreted as a consequence of high electron densities, low electron beam temperatures, high ion charge states and presence of strong magnetic fields. (orig.)

  8. High throughput electrophysiology: new perspectives for ion channel drug discovery

    DEFF Research Database (Denmark)

    Willumsen, Niels J; Bech, Morten; Olesen, Søren-Peter

    2003-01-01

    Proper function of ion channels is crucial for all living cells. Ion channel dysfunction may lead to a number of diseases, so-called channelopathies, and a number of common diseases, including epilepsy, arrhythmia, and type II diabetes, are primarily treated by drugs that modulate ion channels....... A cornerstone in current drug discovery is high throughput screening assays which allow examination of the activity of specific ion channels though only to a limited extent. Conventional patch clamp remains the sole technique with sufficiently high time resolution and sensitivity required for precise and direct...... characterization of ion channel properties. However, patch clamp is a slow, labor-intensive, and thus expensive, technique. New techniques combining the reliability and high information content of patch clamping with the virtues of high throughput philosophy are emerging and predicted to make a number of ion...

  9. Workshop on extremely high energy density plasmas and their diagnostics

    International Nuclear Information System (INIS)

    Ishii, Shozo

    2001-09-01

    Compiled are the papers presented at the workshop on 'Extremely High Energy Density Plasmas and Their Diagnostics' held at National Institute for Fusion Science. The papers cover physics and applications of extremely high-energy density plasmas such as dense z-pinch, plasma focus, and intense pulsed charged beams. Separate abstracts were presented for 7 of the papers in this report. The remaining 25 were considered outside the subject scope of INIS. (author)

  10. High density UO2 powder preparation for HWR fuel

    International Nuclear Information System (INIS)

    Hwang, S. T.; Chang, I. S.; Choi, Y. D.; Cho, B. R.; Kwon, S. W.; Kim, B. H.; Moon, B. H.; Kim, S. D.; Phyu, K. M.; Lee, K. A.

    1992-01-01

    The objective of this project is to study on the preparation of method high density UO 2 powder for HWR Fuel. Accordingly, it is necessary to character ize the AUC processed UO 2 powder and to search method for the preparation of high density UO 2 powder for HWR Fuel. Therefore, it is expected that the results of this study can effect the producing of AUC processed UO 2 powder having sinterability. (Author)

  11. Density-dependent phonoriton states in highly excited semiconductors

    International Nuclear Information System (INIS)

    Nguyen Hong Quang; Nguyen Minh Khue; Nguyen Que Huong

    1995-09-01

    The dynamical aspects of the phonoriton state in highly-photoexcited semiconductors is studied theoretically. The effect of the exciton-exciton interaction and nonbosonic character of high-density excitons are taken into account. Using Green's function method and within the Random Phase Approximation it is shown that the phonoriton dispersion and damping are very sensitive to the exciton density, characterizing the excitation degree of semiconductors. (author). 18 refs, 3 figs

  12. Fifth International Conference on High Energy Density Physics

    Energy Technology Data Exchange (ETDEWEB)

    Beg, Farhat

    2017-07-05

    The Fifth International Conference on High Energy Density Physics (ICHED 2015) was held in the Catamaran Hotel in San Diego from August 23-27, 2015. This meeting was the fifth in a series which began in 2008 in conjunction with the April meeting of the American Physical Society (APS). The main goal of this conference has been to bring together researchers from all fields of High Energy Density Science (HEDS) into one, unified meeting.

  13. Workshop on extremely high energy density plasmas and their diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Shozo (ed.)

    2001-09-01

    Compiled are the papers presented at the workshop on 'Extremely High Energy Density Plasmas and Their Diagnostics' held at National Institute for Fusion Science. The papers cover physics and applications of extremely high-energy density plasmas such as dense z-pinch, plasma focus, and intense pulsed charged beams. Separate abstracts were presented for 7 of the papers in this report. The remaining 25 were considered outside the subject scope of INIS. (author)

  14. The high density effects in the Drell-Yan process

    International Nuclear Information System (INIS)

    Betemps, M.A.; Gay Ducati, M.B.; Ayala Filho, A.L.

    2003-01-01

    The high density effects in the Drell-Yan process (q q-bar → γ * →l + l - ) are investigated for pA collisions at RHIC and LHC energies. In particular, we use a set of nuclear parton distributions that describes the present nuclear eA and pA data in the DGLAP approach including the high density effects introduced in the perturbative Glauber-Mueller approach. (author)

  15. High energy heavy ions: techniques and applications

    International Nuclear Information System (INIS)

    Alonso, J.R.

    1985-04-01

    Pioneering work at the Bevalac has given significant insight into the field of relativistic heavy ions, both in the development of techniques for acceleration and delivery of these beams as well as in many novel areas of applications. This paper will outline our experiences at the Bevalac; ion sources, low velocity acceleration, matching to the synchrotron booster, and beam delivery. Applications discussed will include the observation of new effects in central nuclear collisions, production of beams of exotic short-lived (down to 1 μsec) isotopes through peripheral nuclear collisions, atomic physics with hydrogen-like uranium ions, effects of heavy ''cosmic rays'' on satellite equipment, and an ongoing cancer radiotherapy program with heavy ions. 39 refs., 6 figs., 1 tab

  16. Variation of the Plasma Density in a Glow Discharge Upon the Application of A High Voltage

    International Nuclear Information System (INIS)

    Akman, S.

    2004-01-01

    It is emphasized and demonstrated that, during the formation of an ion-matrix sheath in a glow discharge upon the application of a high voltage pulse, the existing neutral plasma density should change as well. An explicit and practical expression for the neutral plasma density in terms of the gas pressure, secondary electron emission coefficient and the applied voltage is derived, so that the consequent sheath behavior can be formulated correctly. The theoretical result is compared with the data of an experiment, particularly designed and performed to test its validity, and found to be in good agreement with the latter

  17. High resolution spectrometry for relativistic heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Gabor, G; Schimmerling, W; Greiner, D; Bieser, F; Lindstrom, P [California Univ., Berkeley (USA). Lawrence Berkeley Lab.

    1975-12-01

    Several techniques are discussed for velocity and energy spectrometry of relativistic heavy ions with good resolution. A foil telescope with chevron channel plate detectors is described. A test of this telescope was performed using 2.1 GeV/A C/sup 6 +/ ions, and a time-of-flight resolution of 160 ps was measured. Qualitative information on the effect of foil thickness was also obtained.

  18. Density and potential measurements in an intense ion-beam-generated plasma

    International Nuclear Information System (INIS)

    Abt, N.E.

    1982-05-01

    Neutral beams are created by intense large area ion beams which are neutralized in a gas cell. The interaction of the beam with the gas cell creates a plasma. Such a plasma is studied here. The basic plasma parameters, electron temperature, density, and plasma potential, are measured as a function of beam current and neutral gas pressure. These measurements are compared to a model based on the solution of Poisson's equation. Because of the cylindrical geometry the equation cannot be solved analytically. Details of the numerical method are presented

  19. Studying the applicability of densities mixture unfolding for heavy ion jet spectra in the ALICE experiment

    CERN Document Server

    Hackstock, Philip

    2016-01-01

    The results of a three months summer project from July 4th 2016 to September 23rd are presented in this summer student report.\\\\ The method presented in the paper\\footnote{\\url{http://www.sciencedirect.com/science/article/pii/S0168900215000406}} on densities mixture unfolding by Nikolay Gagunashvili and its software implementation were studied. A mind map flowchart, plotting macros and documentation were produced and while an 18 fold performance boost trough parallelization could be achieved, the verdict on the applicability of this method for heavy ion jet spectra in the ALICE experiment remains inconclusive. This is mainly due to a lack of time and complexity of the method and its implementation.

  20. Densities and temperatures at fragment formation in heavy-ion collision

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Akira [Hokkaido Univ., Sapporo (Japan)

    1998-07-01

    In order to clarify whether the liquid-gas phase transition is relevant to the multi-fragment formation found in intermediate energy heavy-ion collisions, we estimate the densities and temperatures at fragment formation in Au+Au collisions at incident energies of 150 MeV/A and 400 MeV/A within the Quantum Molecular Dynamics (QMD) model with and without quantum fluctuations implemented according to the Quantal Langevin (QL) model. The calculated results show that the IMFs are mainly produced inside the unstable region of nuclear matter, which supports the idea of the fragment formation from supercooled nuclear matter. (author)

  1. Ion cyclotron modes in a low density plasma cavity. Part I: Theory

    International Nuclear Information System (INIS)

    Sawley, M.L.

    1990-12-01

    Ion cyclotron modes excited in a low density, cylindrical plasma cavity using an external inductive antenna are investigated theoretically. These modes, which have a long parallel wavelength, exhibit a strong electrostatic character and are only weakly coupled to the antenna fields. It is shown that, despite the low frequency considered, electron dynamics play a dominant role via the effects of both Landau damping and electron inertia. The characteristics of the wavefields associated with these modes, relevant to an experimental investigation, are described. (author) 8 figs., 1 tab., 10 refs

  2. Still rethinking the value of high wood density.

    Science.gov (United States)

    Larjavaara, Markku; Muller-Landau, Helene C

    2012-01-01

    In a previous paper, we questioned the traditional interpretation of the advantages and disadvantages of high wood density (Functional Ecology 24: 701-705). Niklas and Spatz (American Journal of Botany 97: 1587-1594) challenged the biomechanical relevance of studying properties of dry wood, including dry wood density, and stated that we erred in our claims regarding scaling. We first present the full derivation of our previous claims regarding scaling. We then examine how the fresh modulus of rupture and the elastic modulus scale with dry wood density and compare these scaling relationships with those for dry mechanical properties, using almost exactly the same data set analyzed by Niklas and Spatz. The derivation shows that given our assumptions that the modulus of rupture and elastic modulus are both proportional to wood density, the resistance to bending is inversely proportional to wood density and strength is inversely proportional with the square root of wood density, exactly as we previously claimed. The analyses show that the elastic modulus of fresh wood scales proportionally with wood density (exponent 1.05, 95% CI 0.90-1.11) but that the modulus of rupture of fresh wood does not, scaling instead with the 1.25 power of wood density (CI 1.18-1.31). The deviation from proportional scaling for modulus of rupture is so small that our central conclusion remains correct: for a given construction cost, trees with lower wood density have higher strength and higher resistance to bending.

  3. Generation of highly collimated high-current ion beams by skin-layer laser-plasma interaction at relativistic laser intensities

    International Nuclear Information System (INIS)

    Badziak, J.; Jablonski, S.; Glowacz, S.

    2006-01-01

    Generation of fast ion beams by laser-induced skin-layer ponderomotive acceleration has been studied using a two-dimensional (2D) two-fluid relativistic computer code. It is shown that the key parameter determining the spatial structure and angular divergence of the ion beam is the ratio d L /L n , where d L is the laser beam diameter and L n is the plasma density gradient scale length. When d L >>L n , a dense highly collimated megaampere ion (proton) beam of the ion current density approaching TA/cm 2 can be generated by skin-layer ponderomotive acceleration, even with a tabletop subpicosecond laser

  4. How sensitive are di-leptons from ρ mesons to the high baryon density region?

    International Nuclear Information System (INIS)

    Vogel, S.; Schmidt, K.; Santini, E.; Sturm, C.; Bleicher, M.; Petersen, H.; Aichelin, J.

    2008-01-01

    We show that the measurement of dileptons might provide only a restricted view into the most dense stages of heavy-ion reactions. Thus, possible studies of meson and baryon properties at high baryon densities, as, e.g., done at the GSI High Acceptance DiElectron Spectrometer (HADES) and envisioned for the Facility for Antiproton and Ion Research (FAIR) compressed baryonic matter experiments, might observe weaker effects than currently expected in certain approaches. We argue that the strong absorption of resonances in the high-baryon-density region of the heavy-ion collision masks information from the early hot and dense phase due to a strong increase of the total decay width because of collisional broadening. To obtain additional information, we also compare the currently used approaches to extract dileptons from transport simulations, i.e., shining, only vector mesons from final baryon resonance decays and instant emission of dileptons and find a strong sensitivity on the method employed in particular at FAIR and the CERN Super Proton Synchrotron energies. It is shown explicitly that a restriction to ρ meson (and therefore dilepton) production only in final-state baryon resonance decays provide a strong bias toward rather low baryon densities. The results presented are obtained from ultrarelativistic quantum molecular dynamics v2.3 calculations using the standard setup

  5. Thermal spike analysis of highly charged ion tracks

    International Nuclear Information System (INIS)

    Karlušić, M.; Jakšić, M.

    2012-01-01

    The irradiation of material using swift heavy ion or highly charged ion causes excitation of the electron subsystem at nanometer scale along the ion trajectory. According to the thermal spike model, energy deposited into the electron subsystem leads to temperature increase due to electron–phonon coupling. If ion-induced excitation is sufficiently intensive, then melting of the material can occur, and permanent damage (i.e., ion track) can be formed upon rapid cooling. We present an extension of the analytical thermal spike model of Szenes for the analysis of surface ion track produced after the impact of highly charged ion. By applying the model to existing experimental data, more than 60% of the potential energy of the highly charged ion was shown to be retained in the material during the impact and transformed into the energy of the thermal spike. This value is much higher than 20–40% of the transferred energy into the thermal spike by swift heavy ion. Thresholds for formation of highly charged ion track in different materials show uniform behavior depending only on few material parameters.

  6. Study of the ion density of a radio-frequency plasma using electrostatic probes and focussed microwave interferometers

    International Nuclear Information System (INIS)

    Nguyen Cao, L.; Gagne, R.R.J.

    1976-01-01

    In order to verify experimentally and compare recent ion theories for cylindrical electrostatic probes, the ion density in a radio-frequency plasma was evaluated from V-I curves by means of six different theories. At low pressures, the theories of Bernstein and Rabinowitz, of Lam and Laframboise, give values of density which differ respectively by 20, 25 and 30% compared with the values obtained using a 10GHz focussed microwave interferometer. At the continuum limit, The Schulz and Brown's, and Su and Kiel's theories give density values which disagree respectively by 55 and 20%, compared with the values obtained by microwaves. For pressures varying from 0.05 to 3mmHg, the decrease of ion current, as predicted theorically by Waymouth, was observed. The density perturbation near the probe was found to be a dominant factor affecting the precision of density measurements, for pressures up to 2mmHg at least for our experimental conditions [fr

  7. Breast density estimation from high spectral and spatial resolution MRI

    Science.gov (United States)

    Li, Hui; Weiss, William A.; Medved, Milica; Abe, Hiroyuki; Newstead, Gillian M.; Karczmar, Gregory S.; Giger, Maryellen L.

    2016-01-01

    Abstract. A three-dimensional breast density estimation method is presented for high spectral and spatial resolution (HiSS) MR imaging. Twenty-two patients were recruited (under an Institutional Review Board--approved Health Insurance Portability and Accountability Act-compliant protocol) for high-risk breast cancer screening. Each patient received standard-of-care clinical digital x-ray mammograms and MR scans, as well as HiSS scans. The algorithm for breast density estimation includes breast mask generating, breast skin removal, and breast percentage density calculation. The inter- and intra-user variabilities of the HiSS-based density estimation were determined using correlation analysis and limits of agreement. Correlation analysis was also performed between the HiSS-based density estimation and radiologists’ breast imaging-reporting and data system (BI-RADS) density ratings. A correlation coefficient of 0.91 (pdensity estimations. An interclass correlation coefficient of 0.99 (pdensity estimations. A moderate correlation coefficient of 0.55 (p=0.0076) was observed between HiSS-based breast density estimations and radiologists’ BI-RADS. In summary, an objective density estimation method using HiSS spectral data from breast MRI was developed. The high reproducibility with low inter- and low intra-user variabilities shown in this preliminary study suggest that such a HiSS-based density metric may be potentially beneficial in programs requiring breast density such as in breast cancer risk assessment and monitoring effects of therapy. PMID:28042590

  8. Microwave frequency sweep interferometer for plasma density measurements in ECR ion sources: Design and preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Torrisi, Giuseppe [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); University Mediterranea of Reggio Calabria, Reggio Calabria (Italy); Mascali, David; Neri, Lorenzo; Leonardi, Ornella; Celona, Luigi; Castro, Giuseppe; Agnello, Riccardo; Caruso, Antonio; Passarello, Santi; Longhitano, Alberto; Gammino, Santo [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Sorbello, Gino [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); University of Catania, Catania, Italy and INFN-LNS, Catania (Italy); Isernia, Tommaso [University Mediterranea of Reggio Calabria, Reggio Calabria (Italy)

    2016-02-15

    The Electron Cyclotron Resonance Ion Sources (ECRISs) development is strictly related to the availability of new diagnostic tools, as the existing ones are not adequate to such compact machines and to their plasma characteristics. Microwave interferometry is a non-invasive method for plasma diagnostics and represents the best candidate for plasma density measurement in hostile environment. Interferometry in ECRISs is a challenging task mainly due to their compact size. The typical density of ECR plasmas is in the range 10{sup 11}–10{sup 13} cm{sup −3} and it needs a probing beam wavelength of the order of few centimetres, comparable to the chamber radius. The paper describes the design of a microwave interferometer developed at the LNS-INFN laboratories based on the so-called “frequency sweep” method to filter out the multipath contribution in the detected signals. The measurement technique and the preliminary results (calibration) obtained during the experimental tests will be presented.

  9. Kinetic Alfven wave with density variation and loss-cone distribution function of multi-ions in PSBL region

    Science.gov (United States)

    Tamrakar, Radha; Varma, P.; Tiwari, M. S.

    2018-05-01

    Kinetic Alfven wave (KAW) generation due to variation of loss-cone index J and density of multi-ions (H+, He+ and O+) in the plasma sheet boundary layer region (PSBL) is investigated. Kinetic approach is used to derive dispersion relation of wave using Vlasov equation. Variation of frequency with respect to wide range of k⊥ρi (where k⊥ is wave vector across the magnetic field, ρi is gyroradius of ions and i denotes H+, He+ and O+ ions) is analyzed. It is found that each ion gyroradius and number density shows different effect on wave generation with varying width of loss-cone. KAW is generated with multi-ions (H+, He+ and O+) over wide regime for J=1 and shows dissimilar effect for J=2. Frequency is reduced with increasing density of gyrating He+ and O+ ions. Wave frequency is obtained within the reported range which strongly supports generation of kinetic Alfven waves. A sudden drop of frequency is also observed for H+ and He+ ion which may be due to heavy penetration of these ions through the loss-cone. The parameters of PSBL region are used for numerical calculation. The application of these results are in understanding the effect of gyrating multi-ions in transfer of energy and Poynting flux losses from PSBL region towards ionosphere and also describing the generation of aurora.

  10. Effect of Ar ion on the surface properties of low density polyethylene

    Science.gov (United States)

    Zaki, M. F.

    2016-04-01

    In this paper, low-density polyethylene (LDPE) was irradiated by argon ion with different fluences up to 1015ions/cm2. The optical, chemical and hardness properties have been investigated using UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and micro-indentation tester, respectively. The results showed the ion beam bombardment induced decreases in the transmittance of the irradiated polymer samples. This change in transmittance can be attributed to the formation of conjugated bonds i.e. possible formation of defects and/or carbon clusters. The indirect optical band gap decreased from 3.0 eV for the pristine sample to 2.3 eV for that sample irradiated with the highest fluence of the Ar ion beam. Furthermore, the number of carbon atoms and clusters increased with increasing Ar ion fluences. FTIR spectra showed the formation of new bands of the bombarded polymer samples. Furthermore, polar groups were created on the surface of the irradiated samples which refer to the increase of the hydrophilic nature of the surface of the irradiated samples. The Vicker's hardness increased from 4.9 MPa for the pristine sample to 17.9 MPa for those bombarded at the highest fluence. This increase is attributed to the increase in the crosslinking and alterations of the bombarded surface into hydrogenated amorphous carbon, which improves the hardness of the irradiated samples. The bombarded LDPE surfaces may be used in special applications to the field of the micro-electronic devices and shock absorbers.

  11. HITRAP: A Facility for Experiments with Trapped Highly Charged Ions

    International Nuclear Information System (INIS)

    Quint, W.; Dilling, J.; Djekic, S.; Haeffner, H.; Hermanspahn, N.; Kluge, H.-J.; Marx, G.; Moore, R.; Rodriguez, D.; Schoenfelder, J.; Sikler, G.; Valenzuela, T.; Verdu, J.; Weber, C.; Werth, G.

    2001-01-01

    HITRAP is a planned ion trap facility for capturing and cooling of highly charged ions produced at GSI in the heavy-ion complex of the UNILAC-SIS accelerators and the ESR storage ring. In this facility heavy highly charged ions up to uranium will be available as bare nuclei, hydrogen-like ions or few-electron systems at low temperatures. The trap for receiving and studying these ions is designed for operation at extremely high vacuum by cooling to cryogenic temperatures. The stored highly charged ions can be investigated in the trap itself or can be extracted from the trap at energies up to about 10 keV/q. The proposed physics experiments are collision studies with highly charged ions at well-defined low energies (eV/u), high-accuracy measurements to determine the g-factor of the electron bound in a hydrogen-like heavy ion and the atomic binding energies of few-electron systems, laser spectroscopy of HFS transitions and X-ray spectroscopy

  12. Behaviour of tetraalkylammonium ions in high-field asymmetric waveform ion mobility spectrometry.

    Science.gov (United States)

    Aksenov, Alexander A; Kapron, James T

    2010-05-30

    High-field asymmetric waveform ion mobility spectrometry (FAIMS) is an ion-filtering technique recently adapted for use with liquid chromatography/mass spectrometry (LC/MS) to remove interferences during analysis of complex matrices. This is the first systematic study of a series of singly charged tetraalkylammonium ions by FAIMS-MS. The compensation voltage (CV) is the DC offset of the waveform which permits the ion to emerge from FAIMS and it was determined for each member of the series under various conditions. The electrospray ionization conditions explored included spray voltage, vaporizer temperature, and sheath and auxiliary gas pressure. The FAIMS conditions explored included carrier gas flow rate, electrode temperature and composition of the carrier gas. Optimum desolvation was achieved using sufficient carrier gas (flow rate > or = 2 L/min) to ensure stable response. Low-mass ions (m/z 100-200) are more susceptible to changes in electrode temperature and gas composition than high mass ions (m/z 200-700). As a result of this study, ions are reliably analyzed using standard FAIMS conditions (dispersion voltage -5000 V, carrier gas flow rate 3 L/min, 50% helium/50%nitrogen, inner electrode temperature 70 degrees C and outer electrode temperature 90 degrees C). Variation of FAIMS conditions may be of great use for the separation of very low mass tetraalkylammonium (TAA) ions from other TAA ions. The FAIMS conditions do not appear to have a major effect on higher mass ions. Copyright 2010 John Wiley & Sons, Ltd.

  13. Investigations on transport and storage of high ion beam intensities

    International Nuclear Information System (INIS)

    Joshi, Ninad Shrikrishna

    2009-01-01

    In the framework of this thesis the intense low energy ion beam transport was investigated. Especially, the beam transport in toroidal magnetic field configurations was discussed, as it may allow the accumulation of high intensive beams in the future. One of the specific tasks is to design an injection system that can be used for the proposed low energy accumulator ring. A simulation code (TBT) was written to describe the particle motion in curved segments. Particle in Cell techniques were utilized to simulate a multi particle dynamics. A possibility of reading an external data file was made available so that a measured distribution can be used to compare simulation results with measured ones. A second order cloud in cell method was used to calculate charge density and in turn to solve Poisson's equation. Further simulations were performed to study the self field effects on beam transport. Experiments were performed to compare the simulation results and gain practical experience. The preparatory experiments consisted of building and characterization of the ion source in a first step. Along with the momentum spectrometer and emittance scanner the beam properties were studied. Low mass ion beams He + and mixed p, H 2+ , H 3+ beams were analyzed. In the second stage, beams were transported through a solenoid and the phase space distribution was measured as a function of the magnetic field for different beam energies. The phase-space as distributions measured in a first stage were simulated backward and then again forward transported through the solenoid. The simulated results were then compared with the measured distribution. The LINTRA transport program was used. The phase-space distribution was further simulated for transport experiments in a toroidal magnetic field. The transport program that was used to simulate the beam in the toroid was also used to design the injection system. The injection system with its special field configurations was designed to perform

  14. Investigations on transport and storage of high ion beam intensities

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Ninad Shrikrishna

    2009-08-25

    In the framework of this thesis the intense low energy ion beam transport was investigated. Especially, the beam transport in toroidal magnetic field configurations was discussed, as it may allow the accumulation of high intensive beams in the future. One of the specific tasks is to design an injection system that can be used for the proposed low energy accumulator ring. A simulation code (TBT) was written to describe the particle motion in curved segments. Particle in Cell techniques were utilized to simulate a multi particle dynamics. A possibility of reading an external data file was made available so that a measured distribution can be used to compare simulation results with measured ones. A second order cloud in cell method was used to calculate charge density and in turn to solve Poisson's equation. Further simulations were performed to study the self field effects on beam transport. Experiments were performed to compare the simulation results and gain practical experience. The preparatory experiments consisted of building and characterization of the ion source in a first step. Along with the momentum spectrometer and emittance scanner the beam properties were studied. Low mass ion beams He{sup +} and mixed p, H{sup 2+}, H{sup 3+} beams were analyzed. In the second stage, beams were transported through a solenoid and the phase space distribution was measured as a function of the magnetic field for different beam energies. The phase-space as distributions measured in a first stage were simulated backward and then again forward transported through the solenoid. The simulated results were then compared with the measured distribution. The LINTRA transport program was used. The phase-space distribution was further simulated for transport experiments in a toroidal magnetic field. The transport program that was used to simulate the beam in the toroid was also used to design the injection system. The injection system with its special field configurations was

  15. Comparison of low density and high density pedicle screw instrumentation in Lenke 1 adolescent idiopathic scoliosis.

    Science.gov (United States)

    Shen, Mingkui; Jiang, Honghui; Luo, Ming; Wang, Wengang; Li, Ning; Wang, Lulu; Xia, Lei

    2017-08-02

    The correlation between implant density and deformity correction has not yet led to a precise conclusion in adolescent idiopathic scoliosis (AIS). The aim of this study was to evaluate the effects of low density (LD) and high density (HD) pedicle screw instrumentation in terms of the clinical, radiological and Scoliosis Research Society (SRS)-22 outcomes in Lenke 1 AIS. We retrospectively reviewed 62 consecutive Lenke 1 AIS patients who underwent posterior spinal arthrodesis using all-pedicle screw instrumentation with a minimum follow-up of 24 months. The implant density was defined as the number of screws per spinal level fused. Patients were then divided into two groups according to the average implant density for the entire study. The LD group (n = 28) had fewer than 1.61 screws per level, while the HD group (n = 34) had more than 1.61 screws per level. The radiographs were analysed preoperatively, postoperatively and at final follow-up. The perioperative and SRS-22 outcomes were also assessed. Independent sample t tests were used between the two groups. Comparisons between the two groups showed no significant differences in the correction of the main thoracic curve and thoracic kyphosis, blood transfusion, hospital stay, and SRS-22 scores. Compared with the HD group, there was a decreased operating time (278.4 vs. 331.0 min, p = 0.004) and decreased blood loss (823.6 vs. 1010.9 ml, p = 0.048), pedicle screws needed (15.1 vs. 19.6, p density and high density pedicle screw instrumentation achieved satisfactory deformity correction in Lenke 1 AIS patients. However, the operating time and blood loss were reduced, and the implant costs were decreased with the use of low screw density constructs.

  16. Review of highly charged heavy ion production with electron cyclotron resonance ion source (invited)

    International Nuclear Information System (INIS)

    Nakagawa, T.

    2014-01-01

    The electron cyclotron resonance ion source (ECRIS) plays an important role in the advancement of heavy ion accelerators and other ion beam applications worldwide, thanks to its remarkable ability to produce a great variety of intense highly charged heavy ion beams. Great efforts over the past decade have led to significant ECRIS performance improvements in both the beam intensity and quality. A number of high-performance ECRISs have been built and are in daily operation or are under construction to meet the continuously increasing demand. In addition, comprehension of the detailed and complex physical processes in high-charge-state ECR plasmas has been enhanced experimentally and theoretically. This review covers and discusses the key components, leading-edge developments, and enhanced ECRIS performance in the production of highly charged heavy ion beams

  17. High dislocation density of tin induced by electric current

    International Nuclear Information System (INIS)

    Liao, Yi-Han; Liang, Chien-Lung; Lin, Kwang-Lung; Wu, Albert T.

    2015-01-01

    A dislocation density of as high as 10 17 /m 2 in a tin strip, as revealed by high resolution transmission electron microscope, was induced by current stressing at 6.5 x 10 3 A/ cm 2 . The dislocations exist in terms of dislocation line, dislocation loop, and dislocation aggregates. Electron Backscattered Diffraction images reflect that the high dislocation density induced the formation of low deflection angle subgrains, high deflection angle Widmanstätten grains, and recrystallization. The recrystallization gave rise to grain refining

  18. Probing the density dependence of the symmetry potential in intermediate-energy heavy ion collisions

    International Nuclear Information System (INIS)

    Li Qingfeng; Li Zhuxia; Soff, Sven; Gupta, Raj K; Bleicher, Marcus; Stoecker, Horst

    2005-01-01

    Based on the ultrarelativistic quantum molecular dynamics model, the effects of the density-dependent symmetry potential for baryons and of the Coulomb potential for produced mesons are investigated for neutron-rich heavy ion collisions at intermediate energies. The calculated results of the Δ - /Δ ++ and π - /π + production ratios show a clear beam-energy dependence on the density-dependent symmetry potential, which is stronger for the π - /π + ratio close to the pion production threshold. The Coulomb potential of the mesons changes the transverse momentum distribution of the π - /π + ratio significantly, though it alters only slightly the π - and π + total yields. The π - yields, especially at midrapidity or at low transverse momenta and the π - /π + ratios at low transverse momenta are shown to be sensitive probes of the density-dependent symmetry potential in dense nuclear matter. The effect of the density-dependent symmetry potential on the production of both K 0 and K + mesons is also investigated

  19. ADX: a high field, high power density, advanced divertor and RF tokamak

    Science.gov (United States)

    LaBombard, B.; Marmar, E.; Irby, J.; Terry, J. L.; Vieira, R.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; Baek, S.; Beck, W.; Bonoli, P.; Brunner, D.; Doody, J.; Ellis, R.; Ernst, D.; Fiore, C.; Freidberg, J. P.; Golfinopoulos, T.; Granetz, R.; Greenwald, M.; Hartwig, Z. S.; Hubbard, A.; Hughes, J. W.; Hutchinson, I. H.; Kessel, C.; Kotschenreuther, M.; Leccacorvi, R.; Lin, Y.; Lipschultz, B.; Mahajan, S.; Minervini, J.; Mumgaard, R.; Nygren, R.; Parker, R.; Poli, F.; Porkolab, M.; Reinke, M. L.; Rice, J.; Rognlien, T.; Rowan, W.; Shiraiwa, S.; Terry, D.; Theiler, C.; Titus, P.; Umansky, M.; Valanju, P.; Walk, J.; White, A.; Wilson, J. R.; Wright, G.; Zweben, S. J.

    2015-05-01

    The MIT Plasma Science and Fusion Center and collaborators are proposing a high-performance Advanced Divertor and RF tokamak eXperiment (ADX)—a tokamak specifically designed to address critical gaps in the world fusion research programme on the pathway to next-step devices: fusion nuclear science facility (FNSF), fusion pilot plant (FPP) and/or demonstration power plant (DEMO). This high-field (⩾6.5 T, 1.5 MA), high power density facility (P/S ˜ 1.5 MW m-2) will test innovative divertor ideas, including an ‘X-point target divertor’ concept, at the required performance parameters—reactor-level boundary plasma pressures, magnetic field strengths and parallel heat flux densities entering into the divertor region—while simultaneously producing high-performance core plasma conditions that are prototypical of a reactor: equilibrated and strongly coupled electrons and ions, regimes with low or no torque, and no fuelling from external heating and current drive systems. Equally important, the experimental platform will test innovative concepts for lower hybrid current drive and ion cyclotron range of frequency actuators with the unprecedented ability to deploy launch structures both on the low-magnetic-field side and the high-magnetic-field side—the latter being a location where energetic plasma-material interactions can be controlled and favourable RF wave physics leads to efficient current drive, current profile control, heating and flow drive. This triple combination—advanced divertors, advanced RF actuators, reactor-prototypical core plasma conditions—will enable ADX to explore enhanced core confinement physics, such as made possible by reversed central shear, using only the types of external drive systems that are considered viable for a fusion power plant. Such an integrated demonstration of high-performance core-divertor operation with steady-state sustainment would pave the way towards an attractive pilot plant, as envisioned in the ARC concept

  20. Particle accelerator physics and technology for high energy density physics research

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, D.H.H.; Blazevic, A.; Rosmej, O.N.; Spiller, P.; Tahir, N.A.; Weyrich, K. [Gesellschaft fur Schwerionenforschung, GSI-Darmstadt, Plasmaphysik, Darmstadt (Germany); Hoffmann, D.H.H.; Dafni, T.; Kuster, M.; Ni, P.; Roth, M.; Udrea, S.; Varentsov, D. [Darmstadt Univ., Institut fur Kernphysik, Technische Schlobgartenstr. 9 (Germany); Jacoby, J. [Frankfurt Univ., Institut fur Angewandte Physik (Germany); Kain, V.; Schmidt, R.; Zioutas, K. [European Organization for Nuclear Research (CERN), Geneve (Switzerland); Zioutas, K. [Patras Univ., Dept. of Physics (Greece); Mintsev, V.; Fortov, V.E. [Russian Academy of Sciences, Institute of Problems of Chemical Physics, Chernogolovka (Russian Federation); Sharkov, B.Y. [Institut for Theoretical and Experimental Physics ITEP, Moscow (Russian Federation)

    2007-08-15

    Interaction phenomena of intense ion- and laser radiation with matter have a large range of application in different fields of science, extending from basic research of plasma properties to applications in energy science, especially in inertial fusion. The heavy ion synchrotron at GSI now routinely delivers intense uranium beams that deposit about 1 kJ/g of specific energy in solid matter, e.g. solid lead. Our simulations show that the new accelerator complex FAIR (Facility for Antiproton and Ion Research) at GSI as well as beams from the CERN large hadron collider (LHC) will vastly extend the accessible parameter range for high energy density states. A natural example of hot dense plasma is provided by our neighbouring star the sun, and allows a deep insight into the physics of fusion, the properties of matter at high energy density, and is moreover an excellent laboratory for astro-particle physics. As such the sun's interior plasma can even be used to probe the existence of novel particles and dark matter candidates. We present an overview on recent results and developments of dense plasma physics addressed with heavy ion and laser beams combined with accelerator- and nuclear physics technology. (authors)

  1. Production of ultrahigh ion current densities at skin-layer subrelativistic laser-plasma interaction

    Czech Academy of Sciences Publication Activity Database

    Badziak, J.; Glowacz, S.; Jablonski, S.; Parys, P.; Wolowski, J.; Hora, H.; Krása, Josef; Láska, Leoš; Rohlena, Karel

    2005-01-01

    Roč. 46, Suppl. 12B (2005), B541-B555 ISSN 0741-3335 Grant - others:International Atomic Energy Agency in Vienna(XE) 11535/RO; State Committee for Scientific Research (KBN)(PL) 1 PO3B 043 26 Institutional research plan: CEZ:AV0Z10100523 Keywords : high-intensity laser * multiply-charged ions * thin foil targets * picosecond laser * iodine laser * proton acceleration * energetic protons * Ag ions * generation * pulses Subject RIV: BH - Optics, Masers, Laser s Impact factor: 2.902, year: 2005

  2. Generation of intense, high-energy ion pulses by magnetic compression of ion rings

    International Nuclear Information System (INIS)

    Kapetanakos, C.A.

    1981-01-01

    A system based on the magnetic compression of ion rings, for generating intense (High-current), high-energy ion pulses that are guided to a target without a metallic wall or an applied external magnetic field includes a vacuum chamber; an inverse reflex tetrode for producing a hollow ion beam within the chamber; magnetic coils for producing a magnetic field, bo, along the axis of the chamber; a disc that sharpens a magnetic cusp for providing a rotational velocity to the beam and causing the beam to rotate; first and second gate coils for producing fast-rising magnetic field gates, the gates being spaced apart, each gate modifying a corresponding magnetic mirror peak (Near and far peaks) for trapping or extracting the ions from the magnetic mirror, the ions forming a ring or layer having rotational energy; a metal liner for generating by magnetic flux compression a high, time-varying magnetic field, the time-varying magnetic field progressively increasing the kinetic energy of the ions, the magnetic field from the second gate coil decreasing the far mirror peak at the end of the compression for extracting the trapped rotating ions from the confining mirror; and a disc that sharpens a magnetic half-cusp for increasing the translational velocity of the ion beam. The system utilizes the self-magnetic field of the rotating, propagating ion beam to prevent the beam from expanding radially upon extraction

  3. High density plasma productions by hydrogen storage electrode in the Tohoku University Heliac

    International Nuclear Information System (INIS)

    Utoh, H.; Takahashi, H.; Tanaka, Y.; Takenaga, M.; Ogawa, M.; Shinde, J.; Iwazaki, K.; Shinto, K.; Kitajima, S.; Sasao, M.; Nishimura, K.; Inagaki, S.

    2005-01-01

    In the Tohoku University Heliac (TU-Heliac), the influence of a radial electric field on improved modes has been investigated by an electrode biasing. In both positive and negative biasing experiments by the stainless steel (SUS) electrode (cold-electron or ion collection), the improvement of plasma confinement was clearly observed. Furthermore, by negative biasing with a hot cathode (electron injection), the radial electric fields can be actively controlled as a consequence of the control of the electrode current I E . By using the electrode made of a hydrogen storage metal, for example Titanium (Ti) or Vanadium (V), the following possibility can be expected: (1) ions accelerated from the positive biased electrode allow the simulation for the orbit loss of high-energy particles, (2) the electrons/neutral- particles injected from the negative biased electrode provide the production of the high- density plasma, if hydrogen are successfully stored in the electrode. In this present work, several methods were tried as the treatment for hydrogen storage. In the case of the Ti electrode biased positively after the treatment, the improvement of plasma confinement was observed in He plasma, which were same as the experimental results of the SUS electrode. However, in the electron density profiles inside the electrode position there was difference between the biased plasma by the Ti electrode and that by the SUS electrode. In some of Ar discharges biased negatively with the Ti electrode after the treatment, the electron density and the line intensity of H α increased about 10 times of those before biasing. This phenomenon has not been observed in the Ar plasma biased by the SUS electrode. This result suggested that the Ti electrode injected electrons/neutral-hydrogen into the plasma. This high-density plasma productions were observed only 1 ∼ 3 times in the one treatment for hydrogen storage. By using a Vanadium (V) electrode, productions of the high-density plasma

  4. High density operation on the HT-7 superconducting tokamak

    International Nuclear Information System (INIS)

    Xiang Gao

    2000-01-01

    The structure of the operation region has been studied in the HT-7 superconducting tokamak, and progress on the extension of the HT-7 ohmic discharge operation region is reported. A density corresponding to 1.2 times the Greenwald limit was achieved by RF boronization. The density limit appears to be connected to the impurity content and the edge parameters, so the best results are obtained with very clean plasmas and peaked electron density profiles. The peaking factors of electron density profiles for different current and line averaged densities were observed. The density behaviour and the fuelling efficiency for gas puffing (20-30%), pellet injection (70-80%) and molecular beam injection (40-50%) were studied. The core crash sawteeth and MHD behaviour, which were induced by an injected pellet, were observed and the events correlated with the change of current profile and reversed magnetic shear. The MARFE phenomena on HT-7 are summarized. The best correlation has been found between the total input ohmic power and the product of the edge line averaged density and Z eff . HT-7 could be easily operated in the high density region MARFE-free using RF boronization. (author)

  5. Operation and control of high density tokamak reactors

    International Nuclear Information System (INIS)

    Attenberger, S.E.; McAlees, D.G.

    1976-01-01

    The incentive for high density operation of a tokamak reactor was discussed. It is found that high density permits ignition in a relatively small, moderately elongated plasma with a moderate magnetic field strength. Under these conditions, neutron wall loadings approximately 4 MW/m 2 must be tolerated. The sensitivity analysis with respect to impurity effects shows that impurity control will most likely be necessary to achieve the desired plasma conditions. The charge exchange sputtered impurities are found to have an important effect so that maintaining a low neutral density in the plasma is critical. If it is assumed that neutral beams will be used to heat the plasma to ignition, high energy injection is required (approximately 250 keV) when heating is accompished at full density. A scenario is outlined where the ignition temperature is established at low density and then the fueling rate is increased to attain ignition. This approach may permit beams with energies being developed for use in TFTR to be successfully used to heat a high density device of the type described here to ignition

  6. Asymmetric battery having a semi-solid cathode and high energy density anode

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Taison; Chiang, Yet-Ming; Ota, Naoki; Wilder, Throop; Duduta, Mihai

    2017-11-28

    Embodiments described herein relate generally to devices, systems and methods of producing high energy density batteries having a semi-solid cathode that is thicker than the anode. An electrochemical cell can include a positive electrode current collector, a negative electrode current collector and an ion-permeable membrane disposed between the positive electrode current collector and the negative electrode current collector. The ion-permeable membrane is spaced a first distance from the positive electrode current collector and at least partially defines a positive electroactive zone. The ion-permeable membrane is spaced a second distance from the negative electrode current collector and at least partially defines a negative electroactive zone. The second distance is less than the first distance. A semi-solid cathode that includes a suspension of an active material and a conductive material in a non-aqueous liquid electrolyte is disposed in the positive electroactive zone, and an anode is disposed in the negative electroactive zone.

  7. Progress in long sustainment and high density experiments with potential confinement on GAMMA 10

    International Nuclear Information System (INIS)

    Yatsu, K.; Cho, T.; Hirata, M.

    2001-01-01

    The improvement of potential confinement reported in the last IAEA meeting was attained by axisymmetrization of heating pattern of electron cyclotron resonance heating (ECRH). It was experimentally shown that the axisymmetrization of ECRH really produced axisymmetric potential profile. GAMMA 10 experiments have advanced in longer sustainment and high density operation of potential confinement. Experiments for long sustainment of potential confinement were carried out in order to study problems of steady state operation of a tandem mirror reactor. A confining potential was sustained for 150 ms by sequentially injecting two (ECRH) powers in the plug region. It was difficult before to increase the central cell density higher than about 2.5x10 12 cm -3 with and/or without potential confinement due to some density limiting mechanism. In order to overcome this problem, a new higher frequency ion cyclotron range of frequency (ICRF) system (RF3: 36-76 MHz) has been installed. A higher density plasma has been produced with RF3. In addition to RF3, neutral beam injection (NBI) in the anchor cell became effective by reducing neutral gas from beam injectors. Potential confinement experiments have advanced to higher central cell densities up to 4x10 12 cm -3 with RF3 and NBI. A 20% density increase due to the potential confinement was obtained in the high density experiments. (author)

  8. Influence of Electrode Density on the Performance of Li-Ion Batteries: Experimental and Simulation Results

    Directory of Open Access Journals (Sweden)

    Jelle Smekens

    2016-02-01

    Full Text Available Lithium-ion battery (LIB technology further enabled the information revolution by powering smartphones and tablets, allowing these devices an unprecedented performance against reasonable cost. Currently, this battery technology is on the verge of carrying the revolution in road transport and energy storage of renewable energy. However, to fully succeed in the latter, a number of hurdles still need to be taken. Battery performance and lifetime constitute a bottleneck for electric vehicles as well as stationary electric energy storage systems to penetrate the market. Electrochemical battery models are one of the engineering tools which could be used to enhance their performance. These models can help us optimize the cell design and the battery management system. In this study, we evaluate the ability of the Porous Electrode Theory (PET to predict the effect of changing positive electrode density in the overall performance of Li-ion battery cells. It can be concluded that Porous Electrode Theory (PET is capable of predicting the difference in cell performance due to a changing positive electrode density.

  9. Lifetime of anode polymer in magnetically insulated ion diodes for high-intensity pulsed ion beam generation

    International Nuclear Information System (INIS)

    Zhu, X. P.; Dong, Z. H.; Han, X. G.; Xin, J. P.; Lei, M. K.

    2007-01-01

    Generation of high-intensity pulsed ion beam (HIPIB) has been studied experimentally using polyethylene as the anode polymer in magnetically insulated ion diodes (MIDs) with an external magnetic field. The HIPIB is extracted from the anode plasma produced during the surface discharging process on polyethylene under the electrical and magnetic fields in MIDs, i.e., high-voltage surface breakdown (flashover) with bombardments by electrons. The surface morphology and the microstructure of the anode polymer are characterized using scanning electron microscopy and differential scanning calorimetry, respectively. The surface roughening of the anode polymer results from the explosive release of trapped gases or newly formed gases under the high-voltage discharging, leaving fractured surfaces with bubble formation. The polyethylene in the surface layer degrades into low-molecular-weight polymers such as polyethylene wax and paraffin under the discharging process. Both the surface roughness and the fraction of low molecular polymers apparently increase as the discharging times are prolonged for multipulse HIPIB generation. The changes in the surface morphology and the composition of anode polymer lead to a noticeable decrease in the output of ion beam intensity, i.e., ion current density and diode voltage, accompanied with an increase in instability of the parameters with the prolonged discharge times. The diode voltage (or surface breakdown voltage of polymer) mainly depends on the surface morphology (or roughness) of anode polymers, and the ion current density on the composition of anode polymers, which account for the two stages of anode polymer degradation observed experimentally, i.e., stage I which has a steady decrease of the two parameters and stage II which shows a slow decrease, but with an enhanced fluctuation of the two parameters with increasing pulses of HIPIB generation

  10. The emittance of high current heavy ion beams

    International Nuclear Information System (INIS)

    White, N.R.; Devaney, A.S.

    1989-01-01

    Ion implantation is the main application for high current heavy ion beams. Transfer ratio is defined as the ratio of the total ion current leaving the ion source to the current delivered to the endstation. This ratio is monitored and logged and its importance is explained. It is also affected by other factors, such as the isotopic and molecular composition of the total ion beam. The transfer ratio reveals the fraction of ions which are intercepted by parts of the beamline system. The effects of these ions are discussed in two categories: processing purity and reliability. In discussing the emittance of ribbon beams, the two orthogonal planes are usually considered separately. Longitudinal emittance is determined by slot length and by plasma ion temperature. It has already been revealed that the longitudinal divergence of the beams from BF3 is perhaps double that of the beam from arsenic vapour or argon, at the same total perveance from the ion source. This poses the question: why is the ion temperature higher for BF3 than for As or Ar? The transverse emittance is in practical terms dominated by the divergence. It is the most fruitful area for improvement in most real-world systems. There is an intrinsic divergence arising from initial ion energies within the plasma, and there is emittance growth that can occur as a result of aberration in the beam extraction optics. (N.K.)

  11. High volumetric power density, non-enzymatic, glucose fuel cells.

    Science.gov (United States)

    Oncescu, Vlad; Erickson, David

    2013-01-01

    The development of new implantable medical devices has been limited in the past by slow advances in lithium battery technology. Non-enzymatic glucose fuel cells are promising replacement candidates for lithium batteries because of good long-term stability and adequate power density. The devices developed to date however use an "oxygen depletion design" whereby the electrodes are stacked on top of each other leading to low volumetric power density and complicated fabrication protocols. Here we have developed a novel single-layer fuel cell with good performance (2 μW cm⁻²) and stability that can be integrated directly as a coating layer on large implantable devices, or stacked to obtain a high volumetric power density (over 16 μW cm⁻³). This represents the first demonstration of a low volume non-enzymatic fuel cell stack with high power density, greatly increasing the range of applications for non-enzymatic glucose fuel cells.

  12. Noise reduction in muon tomography for detecting high density objects

    International Nuclear Information System (INIS)

    Benettoni, M; Checchia, P; Cossutta, L; Furlan, M; Gonella, F; Pegoraro, M; Garola, A Rigoni; Ronchese, P; Vanini, S; Viesti, G; Bettella, G; Bonomi, G; Donzella, A; Subieta, M; Zenoni, A; Calvagno, G; Cortelazzo, G; Zanuttigh, P; Calvini, P; Squarcia, S

    2013-01-01

    The muon tomography technique, based on multiple Coulomb scattering of cosmic ray muons, has been proposed as a tool to detect the presence of high density objects inside closed volumes. In this paper a new and innovative method is presented to handle the density fluctuations (noise) of reconstructed images, a well known problem of this technique. The effectiveness of our method is evaluated using experimental data obtained with a muon tomography prototype located at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (INFN). The results reported in this paper, obtained with real cosmic ray data, show that with appropriate image filtering and muon momentum classification, the muon tomography technique can detect high density materials, such as lead, albeit surrounded by light or medium density material, in short times. A comparison with algorithms published in literature is also presented

  13. Numerical simulation of SU(2)c high density state

    International Nuclear Information System (INIS)

    Muroya, Shin; Nakamura, Atsushi; Nonaka, Chiho

    2003-01-01

    We report a study of the high baryon number density system with use of the two-color lattice QCD with Wilson fermions[1]. First we investigate thermodynamical quantities such as the Polyakov line, gluon energy density, and baryon number density in the (κ, μ) plane, where κ and μ are the hopping parameter and chemical potential, respectively. Then we calculate propagators of meson (q-barΓq) and baryon (qΓq) states in addition to the potential between quark lines. (author)

  14. Low-frequency oscillations at high density in JFT-2

    International Nuclear Information System (INIS)

    Maeno, Masaki; Katagiri, Masaki; Suzuki, Norio; Fujisawa, Noboru

    1977-12-01

    Low-frequency oscillations in a plasma were measured with magnetic probes and Si surface-barrier detectors, and behaviour of the high density plasmas was studied. The plasma current profile in the phase of decreasing density after the interruption of gas input is more peaked than during gas input. The introduction of hydrogen during a discharge results in a reduction of the impurities flux. The increase of density by fast gas input is limited with a negative voltage spike. Immediately before a negative voltage spike, oscillations of m=1,2 grow, leading to the spike. (auth.)

  15. Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas

    International Nuclear Information System (INIS)

    Ida, K.; Osakabe, M.; Tanaka, K.

    2001-01-01

    A high ion temperature mode (high T i mode) is observed for neutral beam heated plasmas in the Compact Helical System (CHS) Heliotron/torsatron. The high T i mode plasma is characterized by a high central ion temperature, T i (0), and is associated with a peaked electron density profile produced by neutral beam fueling with low wall recycling. Transition from L mode to high T i mode has been studied in CHS. The central ion temperature in the high T i mode discharges reaches to 1 keV which is 2.5 times higher than that in the L mode discharges. The ion thermal diffusivity is significantly reduced by a factor of more than 2-3 in the high T i mode plasma. The ion loss cone is observed in neutral particle flux in the energy range of 1-6 keV with a narrow range of pitch angle (90±10 degree) in the high T i mode. However, the degradation of ion energy confinement due to this loss cone is negligible. (author)

  16. Density-dependent squeezing of excitons in highly excited semiconductors

    International Nuclear Information System (INIS)

    Nguyen Hong Quang.

    1995-07-01

    The time evolution from coherent states to squeezed states of high density excitons is studied theoretically based on the boson formalism and within the Random Phase Approximation. Both the mutual interaction between excitons and the anharmonic exciton-photon interaction due to phase-space filling of excitons are taken into account. It is shown that the exciton squeezing depends strongly on the exciton density in semiconductors and becomes smaller with increasing the latter. (author). 16 refs, 2 figs

  17. High density internal transport barriers for burning plasma operation

    International Nuclear Information System (INIS)

    Pericoli Ridolfini, V.

    2005-01-01

    One of the proposed ITER scenarios foresees the creation and sustainment of an internal transport barrier (ITB) in order to improve the confinement properties of the hot core plasma. The more stringent requests are: the ITB must be sustained with electron heating only with no or very small external momentum source, the strong collisional coupling at the envisaged density (line average >1.0 1020 m-3) must not prevent the barrier existence, the bootstrap current created by the large induced gradients must have a radial profile consistent with that requested by the barrier creation and sustainment. To all these items the studies carried out in FTU in the same density range (ne0 ?1.5 1020 m-3) provide encouraging prospects. With pure electron heating and current drive (LH+ECH) steady electron barrier are generated and maintained with central e- temperature >5.0 keV. Almost full CD conditions are established with a bootstrap current close to 25% of the total and well aligned with that driven by the LH waves and responsible for the barrier building. The clear change in the density fluctuations close to the ITB radius, observed by reflectometry, indicates stabilization of turbulence that is consistent with the drop of the thermal electron diffusivity inside the ITB to very low values, ?e<0.5 m2/s estimated by the transport analysis. The 10 fold neutron rate increase testifies a significant collisional ion heating, even though usually ?Ti0/Ti0 does not exceed 40%, because the e--i + equipartition time, always 4-5 times longer than the energy confinement time, does not allow thermal equilibrium with electrons to be attained. The ion thermal diffusivity inside the barrier must be lowered to the neoclassical level to account for the observed Ti(r) profiles, clearly indicating at least a non-degraded ion transport. The global confinement in turn improves by 1.6 times above the FTU L-scaling. The ITB radius can be controlled by varying the LH power deposition profile that is

  18. A high current metal vapour vacuum arc ion source for ion implantation studies

    International Nuclear Information System (INIS)

    Evans, P.J.; Noorman, J.T.; Watt, G.C.; Cohen, D.D.; Bailey, G.M.

    1989-01-01

    The main features of the metal vapour vacuum arc(MEVA) as an ion source are presented. The technology utilizes the plasma production capabilities of a vacuum arc cathode. Some of the ions produced in this discharge flow through the anode and the 3 extraction grids to form an extracted ion beam. The high beam current and the potential for generating broad beams, make this technology suitable for implantation of large surface areas. The composition of the vacuum arc cathode determines the particular ions obtained from the MEVA source. 3 refs., 1 tab., 2 figs

  19. High energy density capacitors fabricated by thin film technology

    International Nuclear Information System (INIS)

    Barbee, T W; Johnson, G W; Wagner, A V.

    1999-01-01

    Low energy density in conventional capacitors severely limits efforts to miniaturize power electronics and imposes design limitations on electronics in general. We have successfully applied physical vapor deposition technology to greatly increase capacitor energy density. The high dielectric breakdown strength we have achieved in alumina thin films allows high energy density to be achieved with this moderately low dielectric constant material. The small temperature dependence of the dielectric constant, and the high reliability, high resistivity, and low dielectric loss of Al 2 O 3 , make it even more appealing. We have constructed single dielectric layer thin film capacitors and shown that they can be stacked to form multilayered structures with no loss in yield for a given capacitance. Control of film growth morphology is critical for achieving the smooth, high quality interfaces between metal and dielectric necessary for device operation at high electric fields. Most importantly, high rate deposition with extremely low particle generation is essential for achieving high energy storage at a reasonable cost. This has been achieved by reactive magnetron sputtering in which the reaction to form the dielectric oxide has been confined to the deposition surface. By this technique we have achieved a yield of over 50% for 1 cm 2 devices with an energy density of 14 J per cubic centimeter of Al 2 O 3 dielectric material in 1.2 kV, 4 nF devices. By further reducing defect density and increasing the dielectric constant of the material, we will be able to increase capacitance and construct high energy density devices to meet the requirements of applications in power electronics

  20. Ion optics of a high resolution multipassage mass spectrometer with electrostatic ion mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, T [Osaka Univ. (Japan). Dept. of Physics; Baril, M [Departement de Physique, Faculte des Sciences et de Genie, Universite Laval, Ste-Foy, Quebec G1K 7P4 (Canada)

    1995-09-01

    Ion trajectories in an electrostatic ion mirror are calculated. The interferences of the extended fringing fields of the mirror with finite aperture are studied. The results of the calculations are represented by three transfer matrices, which describe ion trajectories under the effects of a fringing field at the entrances, of an idealized mirror region, and of a fringing field at the exit. The focusing effects and ion-optical properties of mass spectrometers with electrostatic ion mirrors can be evaluated by using these transfer matrices. A high performance multipassage mass spectrometer is designed. The system has one magnet and four electrostatic sector analyzers and two ion mirrors. The double focusing condition and stigmatic focusing condition are achieved in any passage of the system. The mass resolution increases linearly with the number of passages in a magnet. (orig.).