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Sample records for lithium vapor laser

  1. Atomic lithium vapor laser isotope separation

    CERN Document Server

    Olivares, I E

    2002-01-01

    An atomic vapor laser isotope separation in lithium was performed using tunable diode lasers. The method permits also the separation of the isotopes between the sup 6 LiD sub 2 and the sup 7 LiD sub 1 lines using a self-made mass separator which includes a magnetic sector and an ion beam designed for lithium. (Author)

  2. Atomic lithium vapor laser isotope separation

    International Nuclear Information System (INIS)

    Olivares, I.E.; Rojas, C.

    2002-01-01

    An atomic vapor laser isotope separation in lithium was performed using tunable diode lasers. The method permits also the separation of the isotopes between the 6 LiD 2 and the 7 LiD 1 lines using a self-made mass separator which includes a magnetic sector and an ion beam designed for lithium. (Author)

  3. The lithium vapor box divertor

    International Nuclear Information System (INIS)

    Goldston, R J; Schwartz, J; Myers, R

    2016-01-01

    It has long been recognized that volumetric dissipation of the plasma heat flux from a fusion power system is preferable to its localized impingement on a material surface. Volumetric dissipation mitigates both the anticipated very high heat flux and intense particle-induced damage due to sputtering. Recent projections to a tokamak demonstration power plant suggest an immense upstream parallel heat flux, of order 20 GW m −2 , implying that fully detached operation may be a requirement for the success of fusion power. Building on pioneering work on the use of lithium by Nagayama et al and by Ono et al as well as earlier work on the gas box divertor by Watkins and Rebut, we present here a concept for a lithium vapor box divertor, in which lithium vapor extracts momentum and energy from a fusion-power-plant divertor plasma, using fully volumetric processes. At the high powers and pressures that are projected this requires a high density of lithium vapor, which must be isolated from the main plasma in order to avoid lithium build-up on the chamber walls or in the plasma. Isolation is achieved through a powerful multi-box differential pumping scheme available only for condensable vapors. The preliminary box-wise calculations are encouraging, but much more work is required to demonstrate the practical viability of this scheme, taking into account at least 2D plasma and vapor flows within and between the vapor boxes and out of the vapor boxes to the main plasma. (paper)

  4. A Lithium Vapor Box Divertor Similarity Experiment

    Science.gov (United States)

    Cohen, Robert A.; Emdee, Eric D.; Goldston, Robert J.; Jaworski, Michael A.; Schwartz, Jacob A.

    2017-10-01

    A lithium vapor box divertor offers an alternate means of managing the extreme power density of divertor plasmas by leveraging gaseous lithium to volumetrically extract power. The vapor box divertor is a baffled slot with liquid lithium coated walls held at temperatures which increase toward the divertor floor. The resulting vapor pressure differential drives gaseous lithium from hotter chambers into cooler ones, where the lithium condenses and returns. A similarity experiment was devised to investigate the advantages offered by a vapor box divertor design. We discuss the design, construction, and early findings of the vapor box divertor experiment including vapor can construction, power transfer calculations, joint integrity tests, and thermocouple data logging. Heat redistribution of an incident plasma-based heat flux from a typical linear plasma device is also presented. This work supported by DOE Contract No. DE-AC02-09CH11466 and The Princeton Environmental Institute.

  5. Lithium vapor/aerosol studies. Interim summary report

    International Nuclear Information System (INIS)

    Whitlow, G.A.; Bauerle, J.E.; Down, M.G.; Wilson, W.L.

    1979-04-01

    The temperature/cover gas pressure regime, in which detectable lithium aerosol is formed in a static system has been mapped for argon and helium cover gases using a portable He--Ne laser device. At 538 0 C (1000 0 F), lithium aerosol particles were observed over the range 0.5 to 20 torr and 2 to 10 torr for argon and helium respectively. The experimental conditions in this study were more conducive to aerosol formation than in a fusion reactor. In the real reactor system, very high intensity mechanical and thermal disturbances will be made to the liquid lithium. These disturbances, particularly transient increases in lithium vapor pressure appear to be capable of producing high concentrations of optically-dense aerosol. A more detailed study is, therefore, proposed using the basic information generated in these preliminary experiments, as a starting point. Areas recommended include the kinetics of aerosol formation and the occurrence of supersaturated vapor during rapid vapor pressure transients, and also the effect of lithium agitation (falls, jets, splashing, etc.) on aerosol formation

  6. Ablative efficiency of lithium triborate laser vaporization and conventional transurethral resection of the prostate: a comparison using transrectal three-dimensional ultrasound volumetry

    Science.gov (United States)

    Gross, Oliver; Sulser, Tullio; Hefermehl, Lukas J.; Strebel, Daniel D.; Largo, Remo; Mortezavi, Ashkan; Poyet, Cédric; Eberli, Daniel; Zimmermann, Matthias; Müller, Alexander; Michel, Maurice S.; Müntener, Michael; Seifert, Hans-Helge; Hermanns, Thomas

    2011-03-01

    Introduction and objectives: It is unknown if tissue ablation following 120W lithium triborate (LBO) laser vaporization (LV) of the prostate is comparable to that following transurethral resection of the prostate (TURP). Therefore, transrectal 3D-ultrasound volumetry of the prostate was performed to compare the efficiency of tissue ablation between LBO-LV and TURP. Methods: Between 03/2008 and 03/2010 110 patients underwent routine LBO-LV (n=61) or TURP (n=49). Transrectal 3D-ultrasound with planimetric volumetry of the prostate was performed pre-operatively, after catheter removal, 6 weeks and 6 months. Results: Median prostate volume was 52.5ml in the LV group and 46.9ml in the TURP group. After catheter removal, median absolute volume reduction (LV: 7.05ml, TURP: 15.8ml) and relative volume reduction (15.9% vs. 34.2%) were significantly lower in the LV group (p<0.001). After 6 weeks/ 6 months, the relative volume reduction but not the absolute remained significantly lower in the LV group. Conclusions: LBO-LV is an efficient procedure evidenced by an absolute tissue ablation not significantly different to that after TURP. However, TURP seems to be superior due to a higher relative tissue ablation. The differences in tissue ablation had no impact on the early clinical outcome. Delayed volume reduction indicates that prostatic swelling occurs early after LV and then decreases subsequently.

  7. Iron bromide vapor laser

    Science.gov (United States)

    Sukhanov, V. B.; Shiyanov, D. V.; Trigub, M. V.; Dimaki, V. A.; Evtushenko, G. S.

    2016-03-01

    We have studied the characteristics of a pulsed gas-discharge laser on iron bromide vapor generating radiation with a wavelength of 452.9 nm at a pulse repetition frequency (PRF) of 5-30 kHz. The maximum output power amounted to 10 mW at a PRF within 5-15 kHz for a voltage of 20-25 kV applied to electrodes of the discharge tube. Addition of HBr to the medium produced leveling of the radial profile of emission. Initial weak lasing at a wavelength of 868.9 nm was observed for the first time, which ceased with buildup of the main 452.9-nm line.

  8. Atomic vapor laser isotope separation

    International Nuclear Information System (INIS)

    Stern, R.C.; Paisner, J.A.

    1985-01-01

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements

  9. Laser spectroscopy in an lithium beam

    International Nuclear Information System (INIS)

    Duarte, A.; Sylvester, G.; Olivares, I.E.

    1998-01-01

    Full text: The absorption and fluorescence spectra were measured in a collimated and non-collimated atomic lithium beam by means of a diode laser. Spectral lines with a similar linewidth as the lines observed before in a stationary lithium vapor were observed in the non-collimated beam. The spatial structure of the gas region which emits fluorescence permits to observe in situ the hyperfine levels of lithium atoms: each level corresponds to a relatively plane and well defined region. This indicates that the atoms leave the oven following straight lines (otherwise the collisions would produce diffuse regions), which is in correspondence to the high values of the free mean path expected for the gas at this density, and the extension of the shadow left at the condensation plate. In the collimated beam (diameter D=1 mm, and divergence of 90 mrad), the absorption spectra has a width of 450 MHz (12 deg K or less), which permits the measurement of the hyperfine structure. In this case, from the absorption data we obtained ρD=2 x 10 14 atoms/m 2 . The temperature obtained from the Doppler width is consistent with the temperature obtained from the beam geometry. The lithium atom flow was measured with a quartz thickness monitor and based on estimates of the initial oven temperature and density measurements. Fluorescence measurements have better sensitivity ab do not present problems in the base line due to etalon effects. It is possible to observe the detail structure of the side wings in the line spectra

  10. DSMC simulations of vapor transport toward development of the lithium vapor box divertor concept

    Science.gov (United States)

    Jagoe, Christopher; Schwartz, Jacob; Goldston, Robert

    2016-10-01

    The lithium vapor divertor box concept attempts to achieve volumetric dissipation of the high heat efflux from a fusion power system. The vapor extracts the heat of the incoming plasma by ionization and radiation, while remaining localized in the vapor box due to differential pumping based on rapid condensation. Preliminary calculations with lithium vapor at densities appropriate for an NSTX-U-scale machine give Knudsen numbers between 0.01 and 1, outside both the range of continuum fluid dynamics and of collisionless Monte Carlo. The direct-simulation Monte Carlo (DSMC) method, however, can simulate rarefied gas flows in this regime. Using the solver contained in the OpenFOAM package, pressure-driven flows of water vapor will be analyzed. The use of water vapor in the relevant range of Knudsen number allows for a flexible similarity experiment to verify the reliability of the code before moving to tests with lithium. The simulation geometry consists of chains of boxes on a temperature gradient, connected by slots with widths that are a representative fraction of the dimensions of the box. We expect choked flow, sonic shocks, and order-of-magnitude pressure and density drops from box to box, but this expectation will be tested in the simulation and then experiment. This work is supported by the Princeton Environmental Institute.

  11. Efficiencies of laser dyes for atomic vapor laser isotope separation

    International Nuclear Information System (INIS)

    Maeda, Mitsuo; Oki, Yuji; Uchiumi, Michihiro; Takao, Takayuki; Igarashi, Kaoru; Shimamoto, Kojiro.

    1995-01-01

    Efficiencies of 30 laser dyes for the atomic vapor laser isotope separation (AVLIS) are experimentally evaluated with a dye laser pumped by a frequency-doubled Nd:YAG laser. On the other hand, a simulation code is developed to describe the laser action of Rhodamine 6G, and the dependence of the laser efficiency on the pump wavelength is calculated. Following conclusions are obtained by these considerations:space: 1) Pyrromethene 567 showed 16% higher laser efficiency than Rhodamine 6G by 532 nm pumping, and Pyrromethene 556 has an ability to provide better efficiency by green light pumping with a Cu vapor laser; 2) Kiton red 620 and Rhodamine 640, whose efficiencies were almost the same as Rhodamine 6G by 532 nm pumping, will show better efficiencies by two-wavelength pumping with a Cu vapor laser. (author)

  12. Laser vapor phase deposition of semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Karlov, N.V.; Luk' ianchuk, B.S.; Sisakian, E.V.; Shafeev, G.A.

    1987-06-01

    The pyrolytic effect of IR laser radiation is investigated with reference to the initiation and control of the vapor phase deposition of semiconductor films. By selecting the gas mixture composition and laser emission parameters, it is possible to control the deposition and crystal formation processes on the surface of semiconductors, with the main control action achieved due to the nonadiabatic kinetics of reactions in the gas phase and high temperatures in the laser heating zone. This control mechanism is demonstrated experimentally during the laser vapor deposition of germanium and silicon films from tetrachlorides on single-crystal Si and Ge substrates. 5 references.

  13. Method of concentrating and separating lithium isotopes by laser

    International Nuclear Information System (INIS)

    Yamashita, Mikio; Kashiwagi, Hiroshi.

    1976-01-01

    Purpose: To eliminate the need for repeating separating operation in many stages and permit concentrated lithium of high purity to be obtained in a short period of time. Constitution: Lithium atom vapor is irradiated by a laser of wavelengths resonant to 6 Li or 7 Li absorption spectra present in the neighborhood of 6,707.84 A or 3,232.61 A (chromatic laser being used for oscillation in the neighborhood of 6,707.84 A and ultraviolet laser used for oscillation in the neighborhood of 6,707.84 A) for selectively exciting 6 Li or 7 Li alone. Then, ionization is brought about by using other types of lasers (ultraviolet Ar ion laser being used as the former wavelength laser and visible Ar ion laser as the latter wavelength laser), and only the ionized isotopes are passed through a mass filter and collected by an ion collector, thereby effecting separation of the ionized isotopes from the non-ionized neutral isotopes and their concentration. (Aizawa, K.)

  14. Recent advances towards a lithium vapor box divertor

    Directory of Open Access Journals (Sweden)

    R.J. Goldston

    2017-08-01

    Full Text Available Fusion power plants are likely to require near complete detachment of the divertor plasma from the divertor target plates, in order to have both acceptable heat flux at the target to avoid prompt damage and also acceptable plasma temperature at the target surface, to minimize long-term erosion. However hydrogenic and impurity puffing experiments show that detached operation leads easily to x-point MARFEs, impure plasmas, degradation in confinement, and lower helium pressure at the exhaust. The concept of the Lithium Vapor Box Divertor is to use local evaporation and strong differential pumping through condensation to localize low-Z gas-phase material that absorbs the plasma heat flux and so achieve detachment while avoiding these difficulties. The vapor localization has been confirmed using preliminary Navier–Stokes calculations. We use ADAS calculations of εcool, the plasma energy lost per injected lithium atom, to estimate the lithium vapor pressure, and so temperature, required for detachment, taking into account power balance. We also develop a simple model of detachment to evaluate the required upstream density, based on further taking into account dynamic pressure balance. A remarkable general result is found, not just for lithium-vapor-induced detachment, that the upstream density divided by the Greenwald-limit density scales as nup/nGW ∝ (P5/8/B3/8 Tdet1/2/(εcool+γTdet, with no explicit size scaling. Tdet is the temperature just before strong pressure loss, assumed to be ∼ ½ of the ionization potential of the dominant recycling species, and γ is the sheath heat transmission factor.

  15. Lithium vapor trapping at a high-temperature lithium PFC divertor target

    Science.gov (United States)

    Jaworski, Michael; Abrams, T.; Goldston, R. J.; Kaita, R.; Stotler, D. P.; de Temmerman, G.; Scholten, J.; van den Berg, M. A.; van der Meiden, H. J.

    2014-10-01

    Liquid lithium has been proposed as a novel plasma-facing material for NSTX-U and next-step fusion devices but questions remain on the ultimate temperature limits of such a PFC during plasma bombardment. Lithium targets were exposed to high-flux plasma bombardment in the Magnum-PSI experimental device resulting in a temperature ramp from room-temperature to above 1200°C. A stable lithium vapor cloud was found to form directly in front of the target and persist to temperature above 1000°C. Consideration of mass and momentum balance in the pre-sheath region of an attached plasma indicates an increase in the magnitude of the pre-sheath potential drop with the inclusion of ionization sources as well as the inclusion of momentum loss terms. The low energy of lithium emission from a surface measured in previous experiments (Contract DE-AC02-09CH11466.

  16. Atomic-vapor-laser isotope separation

    International Nuclear Information System (INIS)

    Davis, J.I.

    1982-10-01

    This paper gives a brief history of the scientific considerations leading to the development of laser isotope separation (LIS) processes. The close relationship of LIS to the broader field of laser-induced chemical processes is evaluated in terms of physical criteria to achieve an efficient production process. Atomic-vapor LIS processes under development at Livermore are reviwed. 8 figures

  17. Photography of a lithium vapor trail during the daytime.

    Science.gov (United States)

    Bedinger, J. F.

    1973-01-01

    Barium and lithium vapors were released from sounding rockets in the thermosphere and observed from aboard a jet aircraft at an altitude of 40,000 ft. The purpose of the releases was to demonstrate the feasibility of an all-weather technique for observing chemical releases and to evaluate methods of observing daytime releases. The selected flight plan of the aircraft allowed a series of observations of the trail from two different straight line paths. Data were recorded photographically. The reduction in sky brightness at the 40,000-ft altitude as compared to the ground allows the use of a filter with a 10-A bandwidth for trail photography in the daytime. These photographs verified the calculation of the usable angular field of the narrow-band filters. Photographs of a 45-min-old trail of lithium vapor were obtained up to 20 min after sunrise at the aircraft. It is concluded that now vapor trail observations may be made during the daytime without regard to weather and logistic restrictions.

  18. Infrared diode laser spectroscopy of lithium hydride

    International Nuclear Information System (INIS)

    Yamada, C.; Hirota, E.

    1988-01-01

    The fundamental and hot bands of the vibration--rotation transitions of 6 LiH, 7 LiH, 6 LiD, and 7 LiD were observed by infrared diode laser spectroscopy at Doppler-limited resolution. Lithium hydride molecules were produced by the reaction of the Li vapor with hydrogen at elevated temperatures. Some 40 transitions were observed and, after combined with submillimeter-wave spectra reported by G. M. Plummer et al. [J. Chem. Phys. 81, 4893 (1984)], were analyzed to yield Dunham-type constants with accuracies more than an order of magnitude higher than those published in the literature. It was clearly demonstrated that the Born--Oppenheimer approximation did not hold, and some parameters representing the breakdown were evaluated. The Born--Oppenheimer internuclear distance r/sup BO//sub e/ was derived to be 1.594 914 26 (59) A, where a new value of Planck's constant recommended by CODATA was employed. The relative intensity of absorption lines was measured to determine the ratio of the permanent dipole moment to its first derivative with respect to the internuclear distance: μ/sub e/ [(partialμpartialr)/sub e/ r/sub e/ ] = 1.743(86). The pressure broadening parameter Δν/sub p/ P was determined to be 6.40 (22) MHzTorr by measuring the linewidth dependence on the pressure of hydrogen, which was about four times larger than the value for the dipole--quadrupole interaction estimated by Kiefer and Bushkovitch's theory

  19. Tabular equation of state of lithium for laser-fusion reactor studies

    International Nuclear Information System (INIS)

    Young, D.A.; Ross, M.; Rogers, F.J.

    1979-01-01

    A tabular lithium equation of state was formulated from three separate equation-of-state models to carry out hydrodynamic simulations of a lithium-waterfall laser-fusion reactor. The models we used are: ACTEX for the ionized fluid, soft-sphere for the liquid and vapor, and pseudopotential for the hot, dense liquid. The models are smoothly joined over the range of density and temperature conditions appropriate for a laser-fusion reactor. We also fitted the models into two forms suitable for hydrodynamic calculations

  20. Tabular equation of state of lithium for laser-fusion reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Young, D.A.; Ross, M.; Rogers, F.J.

    1979-01-19

    A tabular lithium equation of state was formulated from three separate equation-of-state models to carry out hydrodynamic simulations of a lithium-waterfall laser-fusion reactor. The models we used are: ACTEX for the ionized fluid, soft-sphere for the liquid and vapor, and pseudopotential for the hot, dense liquid. The models are smoothly joined over the range of density and temperature conditions appropriate for a laser-fusion reactor. We also fitted the models into two forms suitable for hydrodynamic calculations.

  1. Discharge characteristics of copper vapor laser

    International Nuclear Information System (INIS)

    Nemoto, Koshichi; Fujii, Takashi

    1988-01-01

    This report describes about the copper vapor laser and experimental results of it's discharge characteristics. We measured time varing of plasma regist, and analyzed electron density. (1) The plasma regist is larger than 100Ω at the beginning of discharge, and is rapidly reduced to about 10Ω. (2) The electron density is estimated about 1∼2 x 10 12 /cc at the begining of discharge. (author)

  2. Design and physical features of inductive coaxial copper vapor lasers

    Energy Technology Data Exchange (ETDEWEB)

    Batenin, V. M. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Kazaryan, M. A. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Karpukhin, V. T. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Lyabin, N. A. [Istok Research and Production Corporation (Russian Federation); Malikov, M. M., E-mail: mmalikov@oivtran.ru [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2016-11-15

    A physical model of a copper vapor laser pumped by a pulse-periodic inductive (electrodeless) discharge is considered. The feasibility of efficient laser pumping by an inductive discharge and reaching high output parameters comparable to those of conventional copper vapor lasers pumped by a longitudinal electrode discharge is demonstrated. The design and physical features of an inductive copper vapor laser with an annular working volume are discussed.

  3. Water vapor permeation and dehumidification performance of poly(vinyl alcohol)/lithium chloride composite membranes

    KAUST Repository

    Bui, Duc Thuan; Nida, Aqdas; Ng, Kim  Choon; Chua, Kian  Jon

    2015-01-01

    were observed for membranes with increased lithium chloride content up to 50%. The permeation and sorption properties of the membranes were investigated under different temperatures. The results provided a deeper insight into the membrane water vapor

  4. The reaction kinetics of lithium salt with water vapor

    International Nuclear Information System (INIS)

    Balooch, M.; Dinh, L.N.; Calef, D.F.

    2002-01-01

    The interaction of lithium salt (LiH and/or LiD) with water vapor in the partial pressure range of 10 -5 -2657 Pa has been investigated. The reaction probability of water with LiH cleaved in an ultra high vacuum environment was obtained using the modulated molecular beam technique. This probability was 0.11 and independent of LiH surface temperature, suggesting a negligible activation energy for the reaction in agreement with quantum chemical calculations. The value gradually reduced, however, to 0.007 as the surface concentration of oxygen containing product approached full coverage. As the film grew beyond a monolayer, the phase lag of hydrogen product increased from 0 deg. C to 20 deg. C and the reaction probability reduced further until it approached our detection limit (∼10 -4 ). This phase lag was attributed to a diffusion-limited process in this regime. For micrometer thick hydroxide films grown in high moisture concentration environment on LiD and LiH, the reaction probability reduced to ∼4x10 -7 and was independent of exposure time. In this regime of thick hydroxide films (LiOH and/or LiOD), microcracks generated in the films to release stress provided easier pathways for moisture to reach the interface. A modified microscope, capable of both atomic force microscopy and nanoindentation, was also employed to investigate the surface morphology of hydroxide monohydrate (LiOH · H 2 O and/or LiOD · H 2 O) grown on hydroxide at high water vapor partial pressures and the kinetics of this growth

  5. Water vapor permeation and dehumidification performance of poly(vinyl alcohol)/lithium chloride composite membranes

    KAUST Repository

    Bui, Duc Thuan

    2015-10-09

    Thin and robust composite membranes comprising stainless steel scaffold, fine and porous TiO2 and polyvinyl alcohol/lithium chloride were fabricated and studied for air dehumidification application. Higher hydrophilicity, sorption and permeation were observed for membranes with increased lithium chloride content up to 50%. The permeation and sorption properties of the membranes were investigated under different temperatures. The results provided a deeper insight into the membrane water vapor permeation process. It was specifically noted that lithium chloride significantly reduces water diffusion energy barrier, resulting in the change of permeation energy from positive to negative values. Higher water vapor permeance was observed for the membrane with higher LiCl content at lower temperature. The isothermal air dehumidification tests show that the membrane is suitable for dehumidifying air in high humid condition. Additionally, results also indicate a trade-off between the humidity ratio drop with the water vapor removal rate when varying air flowrate.

  6. Analysis of organic vapors with laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Nozari, Hadi; Tavassoli, Seyed Hassan; Rezaei, Fatemeh

    2015-01-01

    In this paper, laser induced breakdown spectroscopy (LIBS) is utilized in the study of acetone, ethanol, methanol, cyclohexane, and nonane vapors. Carbon, hydrogen, oxygen, and nitrogen atomic emission spectra have been recorded following laser-induced breakdown of the organic vapors that are mixed with air inside a quartz chamber at atmospheric pressure. The plasma is generated with focused, Q-switched Nd:YAG radiation at the wavelength of 1064 nm. The effects of ignition and vapor pressure are discussed in view of the appearance of the emission spectra. The recorded spectra are proportional to the vapor pressure in air. The hydrogen and oxygen contributions diminish gradually with consecutive laser-plasma events without gas flow. The results show that LIBS can be used to characterize organic vapor

  7. Analysis of organic vapors with laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nozari, Hadi; Tavassoli, Seyed Hassan [Laser and Plasma Research Institute, Shahid Beheshti University, G. C, 1983963113 Evin, Tehran (Iran, Islamic Republic of); Rezaei, Fatemeh, E-mail: fatemehrezaei@kntu.ac.ir [Department of Physics, K. N. Toosi University of Technology, 15875-4416 Shariati, Tehran (Iran, Islamic Republic of)

    2015-09-15

    In this paper, laser induced breakdown spectroscopy (LIBS) is utilized in the study of acetone, ethanol, methanol, cyclohexane, and nonane vapors. Carbon, hydrogen, oxygen, and nitrogen atomic emission spectra have been recorded following laser-induced breakdown of the organic vapors that are mixed with air inside a quartz chamber at atmospheric pressure. The plasma is generated with focused, Q-switched Nd:YAG radiation at the wavelength of 1064 nm. The effects of ignition and vapor pressure are discussed in view of the appearance of the emission spectra. The recorded spectra are proportional to the vapor pressure in air. The hydrogen and oxygen contributions diminish gradually with consecutive laser-plasma events without gas flow. The results show that LIBS can be used to characterize organic vapor.

  8. The Atomic Vapor Laser Isotope Separation Program

    International Nuclear Information System (INIS)

    1992-01-01

    This report provides the finding and recommendations on the audit of the Atomic Vapor Laser Isotope Separation (AVLIS) program. The status of the program was assessed to determine whether the Department was achieving objectives stated in its January 1990 Plan for the Demonstration, Transition and Deployment of AVLIS Technology. Through Fiscal Year 1991, the Department had spent about $1.1 billion to develop AVLIS technology. The January 1990 plan provided for AVLIS to be far enough along by September to enable the Department to make a determination of the technical and economic feasibility of deployment. However, the milestones needed to support that determination were not met. An estimated $550 million would be needed to complete AVLIS engineering development and related testing prior to deployment. The earliest possible deployment date has slipped to beyond the year 2000. It is recommended that the Department reassess the requirement for AVLIS in light of program delays and changes that have taken place in the enrichment market since January 1990. Following the reassessment, a decision should be made to either fully support and promote the actions needed to complete AVLIS development or discontinue support for the program entirely. Management's position is that the Department will successfully complete the AVLIS technology demonstration and that the program should continue until it can be transferred to a Government corporation. Although the auditors recognize that AVLIS may be transferred, there are enough technical and financial uncertainties that a thorough assessment is warranted

  9. [Atomic Vapor Laser Isotope Separation (AVLIS) program

    International Nuclear Information System (INIS)

    1992-01-01

    This report summarizes work performed for the Atomic Vapor Laser Isotope Separation (AVLIS) program from January through July, 1992. Each of the tasks assigned during this period is described, and results are presented. Section I details work on sensitivity matrices for the UDS relay telescope. These matrices show which combination of mirror motions may be performed in order to effect certain changes in beam parameters. In Section II, an analysis is given of transmission through a clipping aperture on the launch telescope deformable mirror. Observed large transmission losses could not be simulated in the analysis. An EXCEL spreadsheet program designed for in situ analysis of UDS optical systems is described in Section III. This spreadsheet permits analysis of changes in beam first-order characteristics due to changes in any optical system parameter, simple optimization to predict mirror motions needed to effect a combination of changes in beam parameters, and plotting of a variety of first-order data. Optical systems may be assembled directly from OSSD data. A CODE V nonsequential model of the UDS optical system is described in Section IV. This uses OSSD data to build the UDS model; mirror coordinates may thus be verified. Section V summarizes observations of relay telescope performance. Possible procedures which allow more accurate assessment of relay telescope performance are given

  10. A heated vapor cell unit for dichroic atomic vapor laser lock in atomic rubidium.

    Science.gov (United States)

    McCarron, Daniel J; Hughes, Ifan G; Tierney, Patrick; Cornish, Simon L

    2007-09-01

    The design and performance of a compact heated vapor cell unit for realizing a dichroic atomic vapor laser lock (DAVLL) for the D(2) transitions in atomic rubidium is described. A 5 cm long vapor cell is placed in a double-solenoid arrangement to produce the required magnetic field; the heat from the solenoid is used to increase the vapor pressure and correspondingly the DAVLL signal. We have characterized experimentally the dependence of important features of the DAVLL signal on magnetic field and cell temperature. For the weaker transitions both the amplitude and gradient of the signal are increased by an order of magnitude.

  11. A heated vapor cell unit for dichroic atomic vapor laser lock in atomic rubidium

    International Nuclear Information System (INIS)

    McCarron, Daniel J.; Hughes, Ifan G.; Tierney, Patrick; Cornish, Simon L.

    2007-01-01

    The design and performance of a compact heated vapor cell unit for realizing a dichroic atomic vapor laser lock (DAVLL) for the D 2 transitions in atomic rubidium is described. A 5 cm long vapor cell is placed in a double-solenoid arrangement to produce the required magnetic field; the heat from the solenoid is used to increase the vapor pressure and correspondingly the DAVLL signal. We have characterized experimentally the dependence of important features of the DAVLL signal on magnetic field and cell temperature. For the weaker transitions both the amplitude and gradient of the signal are increased by an order of magnitude

  12. Dynamics of trivalent rare earth molecular vapor lasers

    International Nuclear Information System (INIS)

    Krupke, W.F.

    1976-01-01

    Radiative transition probabilities in neodymium bearing vapors are reviewed and calculations are extended to visible laser transitions in terbium bearing vapor. Nonradiative relaxation processes in the pure and complexed halides are treated in greater detail. While precise, quantitative relaxation probabilities cannot be calculated on the basis of information presently available, plausibility arguments can be established which indicate the order of magnitude of relevant nonradiative decay probabilities. Reference to solid and liquid state nonradiative relaxation data for rare earth ions is reviewed to support the plausibility arguments for the vapor state. Having established the likelihood of high fluorescence yields in the vapor phase, various methods of laser pumping are discussed: optical pumping via parity allowed 4f-5d transitions; optical pumping via charge transfer bands of the vapor complex; and direct electron beam pumping

  13. Study of kinetics of reaction of lithium deuteride powder with O2, CO2 and water vapor

    International Nuclear Information System (INIS)

    Li Gan; Lu Guangda; Jing Wenyong; Qin Cheng

    2004-01-01

    The kinetics of reaction of lithium deuteride powder with O 2 , CO 2 and water vapor is studied. The experimental results show that lithium deuteride reacts with O 2 and CO 2 at very small reaction rate but with water vapor at comparatively larger rate at room temperature (≅28 degree C). The reaction process with water vapor could be described using the unreacted shrinking core model. The second-order kinetics is appropriate for the chemical reaction on the surface of lithium deuteride and reaction rate constant is 0.281 kPa -1 ·min -1

  14. Synthesis of single walled carbon nanotubes by dual laser vaporization

    CSIR Research Space (South Africa)

    Moodley, MK

    2006-07-01

    Full Text Available Single walled carbon nanotubes were synthesized by the laser vaporization of graphite composite targets in a tube furnace. Two pulsed Nd:Yag lasers operating at fundamental (1064 nm) and 2 nd harmonic (532 nm) were combined, focused and evaporated...

  15. Kinetics of excited levels in copper-vapor laser

    International Nuclear Information System (INIS)

    Smilanski, I.

    1981-10-01

    A full and representative description of the excited copper level kinetics in a copper-vapor laser is presented. The research was carried out in three stages. The first stage was the development of a representative and reliable measurement cell. A laser tube constructed of refractory materials and an excitation circuit which provides short pulses at a high repetition rate to heat the tube and excite the copper atoms were developed. This stage was also dedicated to characterizing the laser and studying its scaling laws. In the second stage a rapid neasuring system which avoids the problem of spectral line shape was developed. The system is based on the 'hook' method, which utilizes the anomalous dispersion in the vicinity of an atomic line. The light source, a wide band nitrogen-laser-pumped dye laser, ensures a short sampling time, and the recording system, with a television camera face as the recording medium, allows precise data reduction. In the third stage the excited copper level kinetics in a copper vapor laser is measured. The principal conclusions, that only a small part of the energy in the discharge is utilized to populate the upper laser levels and that the lower laser level population is very large at the end of the excitation pulse and cannot be attributed to relaxation of the upper levels, necessitate a new kinetic description of the copper-vapor laser. The laser is not self-terminating; it is activated and terminated by the electrical discharge

  16. Microcomponents manufacturing for precise devices by copper vapor laser

    Science.gov (United States)

    Gorny, Sergey; Nikonchuk, Michail O.; Polyakov, Igor V.

    2001-06-01

    This paper presents investigation results of drilling of metal microcomponents by copper vapor laser. The laser consists of master oscillator - spatial filter - amplifier system, electronics switching with digital control of laser pulse repetition rate and quantity of pulses, x-y stage with computer control system. Mass of metal, removed by one laser pulse, is measured and defined by means of diameter and depth of holes. Interaction of next pulses on drilled material is discussed. The difference between light absorption and metal evaporation processes is considered for drilling and cutting. Efficiency of drilling is estimated by ratio of evaporation heat and used laser energy. Maximum efficiency of steel cutting is calculated with experimental data of drilling. Applications of copper vapor laser for manufacturing is illustrated by such microcomponents as pin guide plate for printers, stents for cardio surgery, encoded disks for security systems and multiple slit masks for spectrophotometers.

  17. Selective laser vaporization of polypropylene sutures and mesh

    Science.gov (United States)

    Burks, David; Rosenbury, Sarah B.; Kennelly, Michael J.; Fried, Nathaniel M.

    2012-02-01

    Complications from polypropylene mesh after surgery for female stress urinary incontinence (SUI) may require tedious surgical revision and removal of mesh materials with risk of damage to healthy adjacent tissue. This study explores selective laser vaporization of polypropylene suture/mesh materials commonly used in SUI. A compact, 7 Watt, 647-nm, red diode laser was operated with a radiant exposure of 81 J/cm2, pulse duration of 100 ms, and 1.0-mm-diameter laser spot. The 647-nm wavelength was selected because its absorption by water, hemoglobin, and other major tissue chromophores is low, while polypropylene absorption is high. Laser vaporization of ~200-μm-diameter polypropylene suture/mesh strands, in contact with fresh urinary tissue samples, ex vivo, was performed. Non-contact temperature mapping of the suture/mesh samples with a thermal camera was also conducted. Photoselective vaporization of polypropylene suture and mesh using a single laser pulse was achieved with peak temperatures of 180 and 232 °C, respectively. In control (safety) studies, direct laser irradiation of tissue alone resulted in only a 1 °C temperature increase. Selective laser vaporization of polypropylene suture/mesh materials is feasible without significant thermal damage to tissue. This technique may be useful for SUI procedures requiring surgical revision.

  18. Laser microstructuring and annealing processes for lithium manganese oxide cathodes

    International Nuclear Information System (INIS)

    Proell, J.; Kohler, R.; Torge, M.; Ulrich, S.; Ziebert, C.; Bruns, M.; Seifert, H.J.; Pfleging, W.

    2011-01-01

    It is expected that cathodes for lithium-ion batteries (LIB) composed out of nano-composite materials lead to an increase in power density of the LIB due to large electrochemically active surface areas but cathodes made of lithium manganese oxides (Li-Mn-O) suffer from structural instabilities due to their sensitivity to the average manganese oxidation state. Therefore, thin films in the Li-Mn-O system were synthesized by non-reactive radiofrequency magnetron sputtering of a spinel lithium manganese oxide target. For the enhancement of the power density and cycle stability, large area direct laser patterning using UV-laser radiation with a wavelength of 248 nm was performed. Subsequent laser annealing processes were investigated in a second step in order to set up a spinel-like phase using 940 nm laser radiation at a temperature of 680 deg. C. The interaction processes between UV-laser radiation and the material was investigated using laser ablation inductively coupled plasma mass spectroscopy. The changes in phase, structure and grain shape of the thin films due to the annealing process were recorded using Raman spectroscopy, X-ray diffraction and scanning electron microscopy. The structured cathodes were cycled using standard electrolyte and a metallic lithium anode. Different surface structures were investigated and a significant increase in cycling stability was found. Surface chemistry of an as-deposited as well as an electrochemically cycled thin film was investigated via X-ray photoelectron spectroscopy.

  19. Study of Laser Created Metal Vapor Plasmas.

    Science.gov (United States)

    1979-11-16

    Leventhal(1 indicate a value closer to 10-1 cm. might be expected. In the case of’ laser induced penniinf, ionization., wec -,;4-,rit LIP 32 LIP L J where...modified Kramer’s formulae.(25) In figure 11 we demonstrate the impact of associative ionization and laser induced penning ionization upon the temporal...34Laser Induced Fluorescence and Environmental Sensing", Invited paper for Optical Society of America, Topical Mcetixg on "Applications of Laser

  20. Study on the interaction of lithium orthosilicate with water vapor and hydrogen

    International Nuclear Information System (INIS)

    Huber, S.

    1994-09-01

    The present work discusses the adsorption of H 2 O(g) as well as the reactions of D 2 O(g) and D 2 (g) with lithium orthosilicate (Li 4 SiO 4 ), a potential tritium breeding ceramic for future fusion reactors. An apparatus was constructed which permits H 2 O partial pressures as low as 1 μbar to be generated and subsequently measured with high accuracy and precision. Using the frontal analysis of gas chromatography, adsorption isotherms were determined at temperatures and water vapor pressures ranging from 653 to 1093 K and 1 to 10 μbar, respectively. Based upon the data, the tritium inventory at the surface of Li 4 SiO 4 (cr) can be estimated as function of temperature and water vapor concentration in the purge gas of a solid breeder blanket. The reactions of lithium orthosilicate with deuterium oxide and deuterium were studied at high temperature (1160 - 1420K) by means of Knudsen effusion mass spectrometry. In both cases the production of lithium hydroxide and the establishment of an equilibrium between LiOD(g) and D 2 O(g) were observed; D 2 O is derived from oxidation of deuterium, presumably under formation of a reduced surface layer. Equilibrium constants and reaction enthalpies were computed for the reaction of Li 4 SiO 4 (cr) with D 2 O(g). In addition, the vapor pressure of LiOD(g) above Li 4 SiO 4 (cr) was determined as function of temperature and deuterium oxide pressure. Further experiments with lithium orthosilicate were carried out under flowing hydrogen in order to analyze the effects of temperature, H 2 -concentration, gas flow, sample size and sample pretreatment on the formation of water vapor. The results confirm the mass spectrometric findings mentioned above. (orig.) [de

  1. Multiphoton Ionization of Laser Cooled Lithium

    OpenAIRE

    Steinmann, Jochen

    2007-01-01

    Reaction microscopes enable kinematically complete measurements of atomic and molecular fragmentation. An ultracold atomic target is usually provided by a supersonic gas jet. The apparatus developed in the course of this thesis for the first time combines the principle of the reaction microscope with a magneto-optical trap. This allows for the preparation of lithium atoms in the sub-mK range. Being a three-electron system, its simple atomic structure makes lithium a model system of great topi...

  2. Sub-band-gap laser micromachining of lithium niobate

    DEFF Research Database (Denmark)

    Christensen, F. K.; Müllenborn, Matthias

    1995-01-01

    method is reported which enables us to do laser processing of lithium niobate using sub-band-gap photons. Using high scan speeds, moderate power densities, and sub-band-gap photon energies results in volume removal rates in excess of 106µm3/s. This enables fast micromachining of small piezoelectric...

  3. Table of laser lines in gases and vapors

    Energy Technology Data Exchange (ETDEWEB)

    Beck, R; Englisch, W; Guers, K

    1980-01-01

    Numerous applications of lasers require use of specific wavelengths (gas analysis including remote sensing, Raman spectroscopy, optical pumping, laser chemistry and isotope separation). Scientists active in these fields have been compelled to search, in addition to the available, mostly obsolete, laser-line tables, the entire recent literature in order to find suitable laser transitions. Over 6100 laser transitions are presented. An additional list of the lines arranged in order of wavelength should greatly facilitate the search for a laser material that generates a specific wavelength. Further information has also been supplied by listing the pump transition for each of the FIR lines obtained with the optically pumped organic vapors. In addition to the laser lines, the operating conditions under which emission has been achieved are briefly specified at the top of the list for each active medium. The order in which the atomic laser media are listed is based on the periodic system, beginning with the noble gases, continuing with hydrogen and the alkalies to the halogens and the rare earths. The molecular laser media are arranged in order of chemical composition, beginning with the compounds of noble gases (the excimers), then other diatomic molecules, triatomic molecules, and ending with the more complex molecules of organic vapors. (WHK).

  4. Enthalpy model for heating, melting, and vaporization in laser ablation

    OpenAIRE

    Vasilios Alexiades; David Autrique

    2010-01-01

    Laser ablation is used in a growing number of applications in various areas including medicine, archaeology, chemistry, environmental and materials sciences. In this work the heat transfer and phase change phenomena during nanosecond laser ablation of a copper (Cu) target in a helium (He) background gas at atmospheric pressure are presented. An enthalpy model is outlined, which accounts for heating, melting, and vaporization of the target. As far as we know, this is the first model th...

  5. Water vapor-nitrogen absorption at CO2 laser frequencies

    Science.gov (United States)

    Peterson, J. C.; Thomas, M. E.; Nordstrom, R. J.; Damon, E. K.; Long, R. K.

    1979-01-01

    The paper reports the results of a series of pressure-broadened water vapor absorption measurements at 27 CO2 laser frequencies between 935 and 1082 kaysers. Both multiple traversal cell and optoacoustic (spectrophone) techniques were utilized together with an electronically stabilized CW CO2 laser. Comparison of the results obtained by these two methods shows remarkable agreement, indicating a precision which has not been previously achieved in pressure-broadened studies of water vapor. The data of 10.59 microns substantiate the existence of the large (greater than 200) self-broadening coefficients determined in an earlier study by McCoy. In this work, the case of water vapor in N2 at a total pressure of 1 atm has been treated.

  6. Laser-induced chemical vapor deposition reactions

    International Nuclear Information System (INIS)

    Teslenko, V.V.

    1990-01-01

    The results of investigation of chemical reactions of deposition of different substances from the gas phase when using the energy of pulse quasicontinuous and continuous radiation of lasers in the wave length interval from 0.193 to 10.6 μm are generalized. Main attetion is paid to deposition of inorganic substances including nonmetals (C, Si, Ge and others), metals (Cu, Au, Zn, Cd, Al, Cr, Mo, W, Ni) and some simple compounds. Experimental data on the effect of laser radiation parameters and reagent nature (hydrides, halogenides, carbonyls, alkyl organometallic compounds and others) on the deposition rate and deposit composition are described in detail. Specific features of laser-chemical reactions of deposition and prospects of their application are considered

  7. Plasma dynamics from laser ablated solid lithium

    Indian Academy of Sciences (India)

    b; 52.25.-b; 52.70.-m. 1. Introduction. Pulsed laser ablation of a solid sample generates a dense plasma emission in the shape of ... The multichannel analyser plate of the ICCD was gated for as less as 4 ns using ... to explain the atomic collision processes [4]. .... Within duration of laser pulse, there occurs laser-solid interac-.

  8. Distributed feedback dye laser pumped with copper-vapor laser emission

    Energy Technology Data Exchange (ETDEWEB)

    Mirza, S Yu; Soldatov, A N; Sukhanov, V B

    1983-10-01

    The power-spectrum characteristics of the emission of a distributed feedback dye laser pumped with a copper vapor laser have been studied. Laser action has been observed in five dyes over a tuning range of 530-723 nm with an efficiency of 12.4%. The specfic features of the distributed feedback dye laser operating at pulse repetition rates of 4 kHz are discussed.

  9. Diode laser heat treatment of lithium manganese oxide films

    International Nuclear Information System (INIS)

    Pröll, J.; Kohler, R.; Mangang, A.; Ulrich, S.; Bruns, M.; Seifert, H.J.; Pfleging, W.

    2012-01-01

    The crystallization of lithium manganese oxide thin films prepared by radio frequency magnetron sputtering on stainless steel substrates under 10 Pa argon pressure is demonstrated by a laser annealing technique. Laser annealing processes were developed as a function of annealing time and temperature with the objective to form an electrochemically active lithium manganese oxide cathode. It is demonstrated, that laser annealing with 940 nm diode laser radiation and an annealing time of 2000 s at 600 °C delivers appropriate parameters for formation of a crystalline spinel-like phase. Characteristic features of this phase could be detected via Raman spectroscopy, showing the characteristic main Raman band at 627 cm -1 . Within cyclic voltammetric measurements, the two characteristic redox pairs for spinel lithium manganese oxide in the 4 V region could be detected, indicating that the film was well-crystallized and de-/intercalation processes were reversible. Raman post-analysis of a cycled cathode showed that the spinel-like structure was preserved within the cycling process but mechanical degradation effects such as film cracking were observed via scanning electron microscopy. Typical features for the formation of an additional surface reaction layer could be detected using X-ray photoelectron spectroscopy.

  10. Water vapor absorption of carbon dioxide laser radiation

    Science.gov (United States)

    Shumate, M. S.; Menzies, R. T.; Margolis, J. S.; Rosengren, L.-G.

    1976-01-01

    An optoacoustic detector or spectrophone has been used to perform detailed measurements of the absorptivity of mixtures of water vapor in air. A (C-12) (O-16)2 laser was used as the source, and measurements were made at forty-nine different wavelengths from 9.2 to 10.7 microns. The details of the optoacoustic detector and its calibration are presented, along with a discussion of its performance characteristics. The results of the measurements of water vapor absorption show that the continuum absorption in the wavelength range covered is 5-10% lower than previous measurements.

  11. Laser-induced ionization of Na vapor

    International Nuclear Information System (INIS)

    Wu, R.C.Y.; Judge, D.L.; Roussel, F.; Carre, B.; Breger, P.; Spiess, G.

    1982-01-01

    The production of Na 2 + ions by off-resonant laser excitation in the 5800-6200A region mainly results from two-photon absorption by the Na 2 molecule to highly excited gerade states followed by (a) direct ionization by absorbing a third photon or (b) coupling to the molecular Na 2 D 1 PIμ Rydberg state which is subsequently ionized by absorbing a third photon. This mechanism, i.e., a two-photon resonance three photon ionization process, explains a recent experimental observation of Roussel et al. It is suggested that the very same mechanism is also responsible for a similar observation reported by Polak-Dingels et al in their work using two crossed Na beams. In the latter two studies the laser-induced associative ionization processes were reported to be responsible for producing the Na 2 + ion. From the ratio of molecular to atomic concentration in the crossed beam experiment of Polak-Dingels et al we estimate that the cross section for producing Na 2 + through laser-induced associative ionization is at least four orders of magnitude smaller than ionization through the two-photon resonance three photon ionization process in Na 2 molecules

  12. Prospects for trivalent rare earth molecular vapor lasers for fusion

    International Nuclear Information System (INIS)

    Krupke, W.F.

    1976-01-01

    The dynamical properties of three types of RE 3+ molecular vapors were considered: (1) rare earth trihalogens, (2) rare earth trihalogens complexed with transition metal trihalogens, and (3) rare earth chelates. Radiative and nonradiative (unimolecular and bimolecular) transition probabilities have been calculated using phenomenological models predicted on the unique electronic structure of the triply ionized RE ion (well shielded ground electronic configuration of equivalent of electrons). Although all the lanthanide ions have been treated in some detail, specific results are presented for the Nd 3+ and Tb 3+ ions to illustrate the systematics of these vapors as a class of new laser media. Once verified, these phenomenological models will provide a powerful tool for the directed experimental exploration of these systems. Because of the structural similarity to the triply ionized actinides, comments offered here for the lanthanide rare earth series generally apply to gaseous actinide lasers which are also under consideration

  13. Enthalpy model for heating, melting, and vaporization in laser ablation

    Directory of Open Access Journals (Sweden)

    Vasilios Alexiades

    2010-09-01

    Full Text Available Laser ablation is used in a growing number of applications in various areas including medicine, archaeology, chemistry, environmental and materials sciences. In this work the heat transfer and phase change phenomena during nanosecond laser ablation of a copper (Cu target in a helium (He background gas at atmospheric pressure are presented. An enthalpy model is outlined, which accounts for heating, melting, and vaporization of the target. As far as we know, this is the first model that connects the thermodynamics and underlying kinetics of this challenging phase change problem in a self-consistent way.

  14. A dye center laser pumped by emission from copper vapor and dye lasers

    Energy Technology Data Exchange (ETDEWEB)

    Loktyushin, A A; Chernyshev, A I; Soldatov, A N; Sukhanov, V B; Troitskiy, V O

    1983-01-01

    LiF:F2+ lasing is reported for the case of pumping by total emission with frequencies of 570.6 and 578.2 nanometers or by a single yellow copper vapor laser line and emission from an oxazene-17 dye laser excited by emission from a Cu laser. Lasing with a mean power level of 23 milliwatts with a maximum at 911 nanometers is obtained. The maximum efficiency was 3.4 percent with pumping of the dye centers by emission from the yellow Cu laser line. The lasing characteristics of the laser for all the types of pumping used are given.

  15. High-frequency strontium vapor laser for biomedical applications

    Science.gov (United States)

    Hvorostovsky, A.; Kolmakov, E.; Kudashev, I.; Redka, D.; Kancer, A.; Kustikova, M.; Bykovskaya, E.; Mayurova, A.; Stupnikov, A.; Ruzankina, J.; Tsvetkov, K.; Lukyanov, N.; Paklinov, N.

    2018-02-01

    Sr-laser with high pulse repetition rate and high peak radiation power is a unique tool for studying rapidly occurring processes in time (plasma diagnostics, photoablation, etc.). In addition, the study of the frequency characteristics of the active medium of the laser helps to reveal the physics of the formation of an inverse medium in metal vapor lasers. In this paper, an experimental study of an Sr-laser with an active volume of 5.8 cm3 in the pulse repetition frequency range from 25 to 200 kHz is carried out, and a comparison with the frequency characteristics of media with large active volumes is given. We considered the frequency characteristics of the active medium in two modes: at a constant energy in the excitation pulse CU2 / 2 and at a constant average power consumed by the rectifier. In the presented work with a small-volume GRT using the TASITR-5/12 TASITRON switch, a laser was generated for Pairs of strontium at a CSF of 200 kHz. The behavior of the characteristics of the generation lines of 6.456 μm, 1 μm, and 3 μm at increased repetition frequencies is considered. Using the example of large-volume GRT, it is shown that tubes with a large active volume increase their energy characteristics with the growth of the CSF. The possibility of laser operation at pulse repetition rates above 200 kHz is shown.

  16. Study on the lithium compound clusters using laser ablation

    International Nuclear Information System (INIS)

    Yokoyama, Keiichi

    2001-01-01

    Lithium-rich nonstoichiometric binary clusters including hyperlithiated molecules were found to be produced by a nanosecond laser ablation of lithium metal or compound target. Structural information on Li 3 O was obtained for the first time from experiments by measuring and analyzing photoionization efficiency curves of mass-selected ions. For example, the structure of Li 3 O was concluded to have both D 3h and C 2v symmetry. In other words, the vibrational wavefunction even at the ground state spreads over the C 2v and D 3h minima, which has been predicted as the global minimum in the latest theoretical calculations. Also, this is the first experimental evidence for electronomers'. (author)

  17. Spatial diagnostics of the laser induced lithium fluoride plasma

    Energy Technology Data Exchange (ETDEWEB)

    Baig, M. A.; Qamar, Aisha; Fareed, M. A.; Anwar-ul-Haq, M.; Ali, Raheel [Atomic and Molecular Physics Laboratory, Department of Physics, Quaid-i-Azam University, 45320 Islamabad (Pakistan)

    2012-06-15

    We present spatial characteristics of the lithium fluoride plasma generated by the fundamental and second harmonic of a Nd:YAG laser. The plume emission has been recorded spatially using five spectrometers covering the spectral region from 200 nm to 720 nm. The electron density is measured from the Stark broadened line profile of the line at 610.37 nm, whereas the plasma temperature has been determined using the Boltzmann plot method including all the observed spectral lines of lithium. Both the plasma parameters; electron density and plasma temperature decrease with the increase of the distance from the target surface. The thermal conduction towards the target, the radiative cooling of the plasma, and the conversion of thermal energy into kinetic energy are the main mechanisms responsible for the spatially decrease of the plasma parameters.

  18. Alkali-vapor laser-excimer pumped alkali laser

    International Nuclear Information System (INIS)

    Yue Desheng; Li Wenyu; Wang Hongyan; Yang Zining; Xu Xiaojun

    2012-01-01

    Based on the research internal and overseas, the principle of the excimer pumped alkali laser (XPAL) is explained, and the advantages and disadvantages of the XPAL are analyzed. Taking into consideration the difficulties that the diode pumped alkali laser (DPAL) meets on its development, the ability to solve or avoid these difficulties of XPAL is also analyzed. By summing up the achievements of the XPAL, the possible further prospect is proposed. The XPAL is of possibility to improve the performance of the DPAL. (authors)

  19. Development of halide copper vapor laser (the characteristics of using Cul)

    International Nuclear Information System (INIS)

    Oouti, Kazumi; Wada, Yukio; Sasao, Nobuyuki

    1990-01-01

    We are developing halide copper vapor laser that is high efficiency and high reputation rate visible laser. Halide copper vapor laser uses halide copper of copper vapor source. It melts low temperature in comporison with metal copper, because laser tube structure is very simple and it can operate easy. This time, we experiment to use Cul for copper vapor source. We resulted maximum output energy 17.8 (W) and maximum efficiency 0.78 (%) when operate condition was reputation rate 30 (kHz), gas pressure 90 (Torr), charging voltage 13 (kV). (author)

  20. Laser-induced fluorescence line narrowing in atomic vapors

    International Nuclear Information System (INIS)

    Meier, T.; Schuessler, H.A.

    1983-01-01

    The use of highly monochromatic light allows the selective excitation of atoms in vapors if excitation and detection of the fluorescence is carried out collinearly. The atoms capable of absorbing light then form an atomic beam of well defined velocity along the direction of the laser beam, but no velocity selection occurs perpendicular to it. The potential of the technique for Doppler-free atomic spectroscopy and for the study of excited atom collisions is demonstrated using the Na D 1 line as an example

  1. Runaway electron beam control for longitudinally pumped metal vapor lasers

    Science.gov (United States)

    Kolbychev, G. V.; Kolbycheva, P. D.

    1995-08-01

    Physics and techniques for producing of the pulsed runaway electron beams are considered. The main obstacle for increasing electron energies in the beams is revealed to be a self- breakdown of the e-gun's gas-filled diode. Two methods to suppress the self-breakdown and enhance the volumetric discharge producing the e-beam are offered and examined. Each of them provides 1.5 fold increase of the ceiling potential on the gun. The methods also give the ways to control several guns simultaneously. Resulting in the possibility of realizing the powerful longitudinal pumping of metal-vapor lasers on self-terminated transitions of atoms or ions.

  2. Engine flow visualization using a copper vapor laser

    Science.gov (United States)

    Regan, Carolyn A.; Chun, Kue S.; Schock, Harold J., Jr.

    1987-01-01

    A flow visualization system has been developed to determine the air flow within the combustion chamber of a motored, axisymmetric engine. The engine has been equipped with a transparent quartz cylinder, allowing complete optical access to the chamber. A 40-Watt copper vapor laser is used as the light source. Its beam is focused down to a sheet approximately 1 mm thick. The light plane is passed through the combustion chamber, and illuminates oil particles which were entrained in the intake air. The light scattered off of the particles is recorded by a high speed rotating prism movie camera. A movie is then made showing the air flow within the combustion chamber for an entire four-stroke engine cycle. The system is synchronized so that a pulse generated by the camera triggers the laser's thyratron. The camera is run at 5,000 frames per second; the trigger drives one laser pulse per frame. This paper describes the optics used in the flow visualization system, the synchronization circuit, and presents results obtained from the movie. This is believed to be the first published study showing a planar observation of airflow in a four-stroke piston-cylinder assembly. These flow visualization results have been used to interpret flow velocity measurements previously obtained with a laser Doppler velocimetry system.

  3. Effect of vapor plasma on the coupling of laser radiation with aluminum targets

    Energy Technology Data Exchange (ETDEWEB)

    Shui, V H; Kivel, B; Weyl, G M

    1978-12-01

    The effect of vapor plasma on thermal and impulse coupling of laser radiation with aluminum targets is studied to understand and explain experimental data showing anomalously high coupling to 10.6-micron laser radiation. Heating of vapor by inverse bremsstrahlung absorption of laser radiation, subsequent reradiation in the uv and deep uv by ionized species, and vapor layer growth are modeled. A computer code has been developed to solve the governing equations. Major conclusions include the following: (1) vapor plasma radiative transport can be an important mechanism for laser/target coupling, (2) aluminum vapor (density times thickness) approximately equal to 10 to the 17th power/sq cm (corresponding to about 0.01 micron of target material) can result in thermal coupling coefficients of 20% or more, and (3) too much vapor reduces the net flux at the target.

  4. Real-time monitoring of atom vapor concentration with laser absorption spectroscopy

    International Nuclear Information System (INIS)

    Fan Fengying; Gao Peng; Jiang Tao

    2012-01-01

    The technology of laser absorption spectroscopy was used for real-time monitoring of gadolinium atom vapor concentration measurement and the solid state laser pumped ring dye laser was used as optical source. The optical fiber was taken to improve the stability of laser transmission. The multi-pass absorption technology combined with reference optical signal avoided the influence of laser power fluctuation. The experiment result shows that the system based on this detection method has a standard error of 4%. It is proved that the monitoring system provides reliable data for atom vapor laser isotope separation process and the separation efficiency can be improved. (authors)

  5. Vapor-liquid equilibria of the water + 1,3-propanediol and water + 1,3-propanediol + lithium bromide systems

    Energy Technology Data Exchange (ETDEWEB)

    Mun, S Y; Lee, H

    1999-12-01

    Vapor-liquid equilibrium data of the water + 1,3-propanediol and water + 1,3-propanediol + lithium bromide systems were measured at 60, 160, 300, and 760 mmHg at temperatures ranging from 315 to 488 K. The apparatus used in this work is a modified still especially designed for the measurement of low-pressure VLE, in which both liquid and vapor are continuously recirculated. For the analysis of salt-containing solutions, a method incorporating refractometry and gravimetry was used. From the experimental measurements, the effect of lithium bromide on the VLE behavior of water + 1,3-propanediol was investigated. The experimental data of the salt-free system were successfully correlated using the Wilson, NRTL, and UNIQUAC models. In addition, the extended UNIQUAC model of Sander et al. was applied to the VLE calculation of salt-containing mixtures.

  6. The use of laser diodes for control of uranium vaporization rates

    International Nuclear Information System (INIS)

    Hagans, K.; Galkowski, J.

    1993-09-01

    Within the Atomic Vapor Laser Isotope Separation (AVLIS) program we have successfully used the laser absorption spectroscopy technique (LAS) to diagnose process physics performance and control vaporization rate. In the LAS technique, a narrow line-width laser is tuned to an absorption line of the species to be measured. The laser light that is propagated through the sample is and, from this data, the density of the species can be calculated. These laser systems have exclusively consisted of expensive, cumbersome, and difficult to maintain argon-ion-pumped ring dye lasers. While the wavelength flexibility of dye lasers is very useful in a laboratory environment, these laser systems are not well suited for the industrial process control system under development for an AVLIS plant. Diode-lasers offer lower system costs, reduced man power requirements, reduced space requirements, higher system availability, and improved operator safety. We report the. successful deployment and test of a prototype laser diode based uranium vapor rate control system. Diode-laser generated LAS data was used to control the uranium vaporization rate in a hands-off mode for greater than 50 hours. With one minor adjustment the system successfully controlled the vaporization rate for greater than 147 hours. We report excellent agreement with ring dye laser diagnostics and uranium weigh-back measurements

  7. Lithium-ions diffusion kinetic in LiFePO4/carbon nanoparticles synthesized by microwave plasma chemical vapor deposition for lithium-ion batteries

    Science.gov (United States)

    Gao, Chao; Zhou, Jian; Liu, Guizhen; Wang, Lin

    2018-03-01

    Olivine structure LiFePO4/carbon nanoparticles are synthesized successfully using a microwave plasma chemical vapor deposition (MPCVD) method. Microwave is an effective method to synthesize nanomaterials, the LiFePO4/carbon nanoparticles with high crystallinity can shorten diffusion routes for ionic transfer and electron tunneling. Meanwhile, a high quality, complete and homogenous carbon layer with appropriate thickness coating on the surface of LiFePO4 particles during in situ chemical vapor deposition process, which can ensure that electrons are able to transfer fast enough from all sides. Electrochemical impedance spectroscopy (EIS) is carried out to collect information about the kinetic behavior of lithium diffusion in LiFePO4/carbon nanoparticles during the charging and discharging processes. The chemical diffusion coefficients of lithium ions, DLi, are calculated in the range of 10-15-10-9 cm2s-1. Nanoscale LiFePO4/carbon particles show the longer regions of the faster solid-solution diffusion, and corresponding to the narrower region of the slower two-phase diffusion during the insertion/exaction of lithium ions. The CV and galvanostatic charge-discharge measurements show that the LiFePO4/carbon nanoparticles perform an excellent electrochemical performance, especially the high rate capacity and cycle life.

  8. Metal halides vapor lasers with inner reactor and small active volume.

    Science.gov (United States)

    Shiyanov, D. V.; Sukhanov, V. B.; Evtushenko, G. S.

    2018-04-01

    Investigation of the energy characteristics of copper, manganese, lead halide vapor lasers with inner reactor and small active volume 90 cm3 was made. The optimal operating pulse repetition rates, temperatures, and buffer gas pressure for gas discharge tubes with internal and external electrodes are determined. Under identical pump conditions, such systems are not inferior in their characteristics to standard metal halide vapor lasers. It is shown that the use of a zeolite halogen generator provides lifetime laser operation.

  9. Numerical investigation of vessel heating using a copper vapor laser and a pulsed dye laser in treating vascular skin lesions

    Science.gov (United States)

    Pushkareva, A. E.; Ponomarev, I. V.; Isaev, A. A.; Klyuchareva, S. V.

    2018-02-01

    A computer simulation technique was employed to study the selective heating of a tissue vessel using emission from a pulsed copper vapor laser and a pulsed dye laser. The depth and size of vessels that could be selectively and safely removed were determined for the lasers under examination.

  10. Vapor plume oscillation mechanisms in transient keyhole during tandem dual beam fiber laser welding

    Science.gov (United States)

    Chen, Xin; Zhang, Xiaosi; Pang, Shengyong; Hu, Renzhi; Xiao, Jianzhong

    2018-01-01

    Vapor plume oscillations are common physical phenomena that have an important influence on the welding process in dual beam laser welding. However, until now, the oscillation mechanisms of vapor plumes remain unclear. This is primarily because mesoscale vapor plume dynamics inside a millimeter-scale, invisible, and time-dependent keyhole are difficult to quantitatively observe. In this paper, based on a developed three-dimensional (3D) comprehensive model, the vapor plume evolutions in a dynamical keyhole are directly simulated in tandem dual beam, short-wavelength laser welding. Combined with the vapor plume behaviors outside the keyhole observed by high-speed imaging, the vapor plume oscillations in dynamical keyholes at different inter-beam distances are the first, to our knowledge, to be quantitatively analyzed. It is found that vapor plume oscillations outside the keyhole mainly result from vapor plume instabilities inside the keyhole. The ejection velocity at the keyhole opening and dynamical behaviors outside the keyhole of a vapor plume both violently oscillate with the same order of magnitude of high frequency (several kHz). Furthermore, the ejection speed at the keyhole opening and ejection area outside the keyhole both decrease as the beam distance increases, while the degree of vapor plume instability first decreases and then increases with increasing beam distance from 0.6 to 1.0 mm. Moreover, the oscillation mechanisms of a vapor plume inside the dynamical keyhole irradiated by dual laser beams are investigated by thoroughly analyzing the vapor plume occurrence and flow process. The vapor plume oscillations in the dynamical keyhole are found to mainly result from violent local evaporations and severe keyhole geometry variations. In short, the quantitative method and these findings can serve as a reference for further understanding of the physical mechanisms in dual beam laser welding and of processing optimizations in industrial applications.

  11. Selection of an analytical line for determining lithium in aluminum alloys by laser induced breakdown spectrometry

    International Nuclear Information System (INIS)

    Lednev, V.N.; Yakovlev, A.V.; Labutin, T.A.; Popov, A.M.; Zorov, N.B.

    2007-01-01

    Possibilities for determining lithium in aluminum alloys by laser spark spectrometry are studied. The optimum conditions for registering the emission signal of lithium at which the effect of the continuous background radiation of the laser plasma attains a minimum are found. The possibility of determining lithium by laser spark spectrometry using the spectral line at 610 nm is studied for the first time. A comparison of the detection limits and sensitivities of determining lithium by emission its lines at 610 and 671 nm has indicated the advisability of using the line 610 nm for the studied alloys. The detection limit calculated using the 3σ test was found to be 230 ppm (610 nm) and 870 ppm (671 nm) [ru

  12. Dye laser with distributed feedback and with pumping by copper-vapor laser

    Energy Technology Data Exchange (ETDEWEB)

    Mirza, S Yu; Soldatov, A N; Sukhanov, V B

    1983-10-01

    An experimental study was made for determining the characteristics of dye lasers with distributed feedback, not requiring intricate resonator structures, and the feasibility of their pumping with radiation from a metal-vapor laser. The experiments were performed with five different dyes lasing in the yellow-red (510.6 - 578.2 nm) range of the spectrum: rhodamine 110, 6G, S and ocazine 17,1 in ethyl alcohol solution. The optical equipment included a copper-vapor pumping laser with the gas-discharge tube inside a telescopic resonator of the unstable type. Pumping pulses of 20 ns duration were generated at 510.6 and 578.2 nm wavelengths and a 4 kHz repetition rate. The pumping power was varied by means of an interference filter smoothly adjustable through rotation. The pumping laser beam was focused by a cylindrical lens on the dye cell. At optimum dye concentrations, corresponding to a maximum attainable emission power, dye concentrate was added into the circulation system for determining the dependence of the pumping threshold power on the dye concentration. Also measured were the dependence of the emission efficiency on the pumping power and the tuning range of each dye laser. The efficiency was found to remain constant over the pumping power range from threshold level to eight times higher level. The results reveal different angles of laser beam divergence in the vertical plane and in the horizontal plane, the divergence angle being four times larger in the vertical plane. The conversion efficiency increased, without significant changes in spectral characteristics, with a single annular reflector instead of two reflectors. 9 references, 4 figures, 1 table.

  13. Acetone vapor sensing using a vertical cavity surface emitting laser diode coated with polystyrene

    DEFF Research Database (Denmark)

    Ansbæk, Thor; Nielsen, Claus Højgaard; Larsen, Niels Bent

    2009-01-01

    We report theoretical and experimental on a new vapor sensor, using a single-mode vertical-cavity surface-emitting laser (VCSEL) coated with a polymer sensor coating, which can detect acetone vapor at a volume fraction of 2.5%. The sensor provides the advantage of standard packaging, small form...

  14. Laser vaporization/ionization interface for coupling microscale separation techniques with mass spectrometry

    Science.gov (United States)

    Yeung, E.S.; Chang, Y.C.

    1999-06-29

    The present invention provides a laser-induced vaporization and ionization interface for directly coupling microscale separation processes to a mass spectrometer. Vaporization and ionization of the separated analytes are facilitated by the addition of a light-absorbing component to the separation buffer or solvent. 8 figs.

  15. UV laser-assisted fabrication of ridge waveguides in lithium niobate crystals

    OpenAIRE

    Sones, C.L.; Ying, C.Y.J.; Eason, R.W.; Mailis, S.; Ganguly, P.; Soergel, E.

    2010-01-01

    We present a UV laser-assisted method for the fabrication of ridge waveguides in lithium niobate. The UV laser irradiation step provides the refractive index change required for the vertical light confinement in the waveguide and also defines the ferroelectric domain pattern which produces the ridge structures after chemical etching.

  16. Lithium

    Science.gov (United States)

    Bradley, Dwight C.; Stillings, Lisa L.; Jaskula, Brian W.; Munk, LeeAnn; McCauley, Andrew D.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Lithium, the lightest of all metals, is used in air treatment, batteries, ceramics, glass, metallurgy, pharmaceuticals, and polymers. Rechargeable lithium-ion batteries are particularly important in efforts to reduce global warming because they make it possible to power cars and trucks from renewable sources of energy (for example, hydroelectric, solar, or wind) instead of by burning fossil fuels. Today, lithium is extracted from brines that are pumped from beneath arid sedimentary basins and extracted from granitic pegmatite ores. The leading producer of lithium from brine is Chile, and the leading producer of lithium from pegmatites is Australia. Other potential sources of lithium include clays, geothermal brines, oilfield brines, and zeolites. Worldwide resources of lithium are estimated to be more than 39 million metric tons, which is enough to meet projected demand to the year 2100. The United States is not a major producer at present but has significant lithium resources.

  17. Vapor-melt Ratio in Laser Fine Cutting of Slot Arrays

    International Nuclear Information System (INIS)

    Wang Xuyue; Meng Qingxuan; Kang Renke; Xu Wenji; Guo Dongming; Wang Lianji

    2011-01-01

    In order to improve cut quality for slot arrays, a new method of laser fine cutting under the consideration of the ratio of vapor to melt is presented. Laser cutting of 6063 aluminum alloy sheet, 0.5 mm in thickness, was carried out on a JK701H Nd:YAG pulse laser cutting system. The effects of vapor-melt ratio on kerf width, surface roughness and recast layer were studied which relate cutting qualities. Observation on the cut samples with different vapor-melt ratios (0.687, 1.574, 3.601 varied with laser power increasing, and 1.535, 3.601, 7.661 with decreasing of beam cutting speed) shows that high vapor-melt ratio improves laser cut quality clearly. Kerf width 0.2 mm of smooth area on kerf top area and thickness 2.03 μm of recast layer are obtained. No dross was found on the kerf bottom and the percentage of the smooth area is up to 40% out of whole kerf side. The research on vapor-melt ratio provides a deeper understanding of laser cutting and improves laser cut quality effectively.

  18. Pulsed CO2 laser for intra-articular cartilage vaporization and subchondral bone perforation in horses

    Science.gov (United States)

    Nixon, Alan J.; Roth, Jerry E.; Krook, Lennart P.

    1991-05-01

    A pulsed carbon dioxide laser was used to vaporize articular cartilage in four horses, and perforate the cartilage and subchondral bone in four horses. Both intercarpal joints were examined arthroscopically and either a 1 cm cartilage crater or a series of holes was created in the third carpal bone of one joint. The contralateral carpus served as a control. The horses were evaluated clinically for 8 weeks, euthanatized and the joints examined radiographically, grossly, and histologically. Pulsed carbon dioxide laser vaporized cartilage readily but penetrated bone poorly. Cartilage vaporization resulted in no greater swelling, heat, pain on flexion, lameness, or synovial fluid reaction than the sham procedure. Laser drilling resulted in a shallow, charred hole with a tenacious carbon residue, and in combination with the thermal damage to deeper bone, resulted in increased swelling, mild lameness and a low-grade, but persistent synovitis. Cartilage removal by laser vaporization resulted in rapid regrowth with fibrous and fibrovascular tissue and occasional regions of fibrocartilage at week 8. The subchondral bone, synovial membrane, and draining lymph nodes appeared essentially unaffected by the laser cartilage vaporization procedure. Conversely, carbon dioxide laser drilling of subchondral bone resulted in poor penetration, extensive areas of thermal necrosis of bone, and significant secondary damage to the apposing articular surface of the radial carpal bone. The carbon dioxide laser is a useful intraarticular instrument for removal of cartilage and has potential application in inaccessible regions of diarthrodial joints. It does not penetrate bone sufficiently to have application in subchondral drilling.

  19. Alternative applications of atomic vapor laser isotope separation technology

    International Nuclear Information System (INIS)

    1991-01-01

    This report was commissioned by the Secretary of Energy. It summarizes the main features of atomic vapor laser isotope separation (AVLIS) technology and subsystems; evaluates applications, beyond those of uranium enrichment, suggested by Lawrence Livermore National Laboratory (LLNL) and a wide range of US industries and individuals; recommends further work on several applications; recommends the provision of facilities for evaluating potential new applications; and recommends the full involvement of end users from the very beginning in the development of any application. Specifically excluded from this report is an evaluation of the main AVLIS missions, uranium enrichment and purification of plutonium for weapons. In evaluating many of the alternative applications, it became clear that industry should play a greater and earlier role in the definition and development of technologies with the Department of Energy (DOE) if the nation is to derive significant commercial benefit. Applications of AVLIS to the separation of alternate (nonuranium) isotopes were considered. The use of 157 Gd as burnable poison in the nuclear fuel cycle, the use 12 C for isotopically pure diamond, and the use of plutonium isotopes for several nonweapons applications are examples of commercially useful products that might be produced at a cost less than the product value. Separations of other isotopes such as the elemental constituents of semiconductors were suggested; it is recommended that proposed applications be tested by using existing supplies to establish their value before more efficient enrichment processes are developed. Some applications are clear, but their production costs are too high, the window of opportunity in the market has passed, or societal constraints (e.g., on reprocessing of reactor fuel) discourage implementation

  20. Quantitative liquid and vapor distribution measurements in evaporating fuel sprays using laser-induced exciplex fluorescence

    International Nuclear Information System (INIS)

    Fansler, Todd D; Drake, Michael C; Gajdeczko, Boguslaw; Düwel, Isabell; Koban, Wieland; Zimmermann, Frank P; Schulz, Christof

    2009-01-01

    Fully quantitative two-dimensional measurements of liquid- and vapor-phase fuel distributions (mass per unit volume) from high-pressure direct-injection gasoline injectors are reported for conditions of both slow and rapid vaporization in a heated, high-pressure spray chamber. The measurements employ the coevaporative gasoline-like fluorobenzene (FB)/diethylmethylamine (DEMA)/hexane exciplex tracer/fuel system. In contrast to most previous laser-induced exciplex-fluorescence (LIEF) experiments, the quantitative results here include regions in which liquid and vapor fuel coexist (e.g. near the injector exit). A unique aspect is evaluation of both vapor- and liquid-phase distributions at varying temperature and pressure using only in situ vapor-phase fluorescence calibration measurements at room temperature and atmospheric pressure. This approach draws on recent extensive measurements of the temperature-dependent spectroscopic properties of the FB–DEMA exciplex system, in particular on knowledge of the quantum efficiencies of the vapor-phase and liquid-phase (exciplex) fluorescence. In addition to procedures necessary for quantitative measurements, we discuss corrections for liquid–vapor crosstalk (liquid fluorescence that overlaps the vapor-fluorescence bandpass), the unknown local temperature due to vaporization-induced cooling, and laser-sheet attenuation by scattering and absorption

  1. Histologic comparison of the pulsed dye laser and copper vapor laser effects on pig skin

    Energy Technology Data Exchange (ETDEWEB)

    Tan, O.T.; Stafford, T.J.; Murray, S.; Kurban, A.K. (Boston Univ. Medical Center, MA (USA))

    1990-01-01

    Albino pig skin was exposed to the copper vapor (CVL) and flash-lamp pulsed dye (PDL) lasers at 578 nm with a 3 mm diameter spotsize over a range of fluences until purpura and whitening were first established. The total irradiation time was the parameter that was varied in order for the CVL to reach the desired fluence. The lowest fluence producing each clinical endpoint was designated the threshold fluence: 34 J/cm{sup 2} was required to produce purpura using the CVL compared to 7.5 J/cm{sup 2} with the PDL laser. Histologically, skin exposed to purpura fluences from the CVL revealed the presence of constricted, disrupted papillary dermal blood vessels with trapped RBC's within them which were unlike those exposed to PDL where the irradiated vessels were dilated and packed with masses of intravascular agglutinated RBC's. The whitening threshold fluences for the CVL and PDL lasers were 67 J/cm{sup 2} and 29 J/cm{sup 2}, respectively. Streaming of epidermal cells and dermal collagen denaturation were observed in CVL irradiated skin, compared to occasional dyskeratotic epidermal cells and focal dermal collagen denaturation following PDL exposure. The mechanisms responsible for the clinical and histologic changes produced by the two laser systems are discussed.

  2. Electrospun Polymer Fiber Lasers for Applications in Vapor Sensing

    DEFF Research Database (Denmark)

    Krämmer, Sarah; Laye, Fabrice; Friedrich, Felix

    2017-01-01

    of the narrow lasing modes upon uptake of alcohol vapors (model vapors are methanol and ethanol) serves as sensor signal. Thus, the high sensitivity related to the spectral line shifts of cavity-based transducers can be combined with the fiber's large surface to volume ratio. The resulting optical sensors...

  3. Using laser absorption spectroscopy to monitor composition and physical properties of metal vapors

    International Nuclear Information System (INIS)

    Berzins, L.V.

    1993-01-01

    The Atomic Vapor Laser Isotope Separation (AVLIS) program has been using laser absorption spectroscopy to monitor vapor densities for over 15 years. Laser absorption spectroscopy has proven itself to be an accurate and reliable method to monitor both density and composition. During this time the diagnostic has moved from a research tool toward a robust component of a process control system. The hardware used for this diagnostic is discussed elsewhere at this symposium. This paper describes how the laser absorption spectroscopy diagnostic is used as a component of a process control system as well as supplying detailed measurements on vapor densities, composition, flow velocity, internal and kinetic temperatures, and constituent distributions. Examples will be drawn from the uranium AVLIS program. In addition potential applications such as composition control in the production of metal matrix composites or aircraft alloys will be discussed

  4. Modeling of a diode-pumped thin-disk cesium vapor laser

    Science.gov (United States)

    An, Guofei; Cai, He; Liu, Xiaoxu; Han, Juhong; Zhang, Wei; Wang, Hongyuan; Wang, You

    2018-03-01

    A diode pumped alkali laser (DPAL) provides a significant potential for construction of high-powered lasers. Until now, a series of models have been established to analyze the kinetic process and most of them are based on the end-pumped alkali laser system in which the vapor cell are usually cylindrical and cuboid. In this paper, a mathematic model is constructed to investigate the kinetic processes of a diode pumped thin-disk cesium vapor laser, in which the cesium vapor and the buffer gases are beforehand filled in a sealed glass cell with a thin-disk structure. We systemically study the influences of the cell temperature and cell thickness on the output features of a thin-disk DPAL. Further, we study the thin-disk DPAL with the W-shaped resonator and multiple-disk configuration. To the best of our knowledge, there have not been any similar reports so far.

  5. Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing

    OpenAIRE

    Ly, Sonny; Rubenchik, Alexander M.; Khairallah, Saad A.; Guss, Gabe; Matthews, Manyalibo J.

    2017-01-01

    The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas...

  6. Laser pulse propagation in a meter scale rubidium vapor/plasma cell in AWAKE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Joulaei, A. [Max-Planck Institute for Physics, Munich (Germany); University of Mazandaran (Iran, Islamic Republic of); Moody, J. [Max-Planck Institute for Physics, Munich (Germany); Berti, N.; Kasparian, J. [University of Geneva (Switzerland); Mirzanejhad, S. [University of Mazandaran (Iran, Islamic Republic of); Muggli, P. [Max-Planck Institute for Physics, Munich (Germany)

    2016-09-01

    We present the results of numerical studies of laser pulse propagating in a 3.5 cm Rb vapor cell in the linear dispersion regime by using a 1D model and a 2D code that has been modified for our special case. The 2D simulation finally aimed at finding laser beam parameters suitable to make the Rb vapor fully ionized to obtain a uniform, 10 m-long, at least 1 mm in radius plasma in the next step for the AWAKE experiment. - Highlights: • Discussion the AWAKE plasma source based on photoionization of rubidium vapor with a TW/cm^2 Intensity laser with a spectrum across valence ground state transition resonances. • Examines the propagation of the AWAKE ionization laser through rubidium vapor at design density on a small scale and reduced intensity with a linear numerical model compared to experimental results. • Discusses physics of pulse propagation through the vapor at high intensity regime where strong ionization occurs within the laser pulse.

  7. Desorption/ablation of lithium fluoride induced by extreme ultraviolet laser radiation

    Directory of Open Access Journals (Sweden)

    Blejchař Tomáš

    2016-06-01

    Full Text Available The availability of reliable modeling tools and input data required for the prediction of surface removal rate from the lithium fluoride targets irradiated by the intense photon beams is essential for many practical aspects. This study is motivated by the practical implementation of soft X-ray (SXR or extreme ultraviolet (XUV lasers for the pulsed ablation and thin film deposition. Specifically, it is focused on quantitative description of XUV laser-induced desorption/ablation from lithium fluoride, which is a reference large band-gap dielectric material with ionic crystalline structure. Computational framework was proposed and employed here for the reconstruction of plume expansion dynamics induced by the irradiation of lithium fluoride targets. The morphology of experimentally observed desorption/ablation craters were reproduced using idealized representation (two-zone approximation of the laser fluence profile. The calculation of desorption/ablation rate was performed using one-dimensional thermomechanic model (XUV-ABLATOR code taking into account laser heating and surface evaporation of the lithium fluoride target occurring on a nanosecond timescale. This step was followed by the application of two-dimensional hydrodynamic solver for description of laser-produced plasma plume expansion dynamics. The calculated plume lengths determined by numerical simulations were compared with a simple adiabatic expansion (blast-wave model.

  8. Optoacoustic measurements of water vapor absorption at selected CO laser wavelengths in the 5-micron region

    Science.gov (United States)

    Menzies, R. T.; Shumate, M. S.

    1976-01-01

    Measurements of water vapor absorption were taken with a resonant optoacoustical detector (cylindrical pyrex detector, two BaF2 windows fitted into end plates at slight tilt to suppress Fabry-Perot resonances), for lack of confidence in existing spectral tabular data for the 5-7 micron region, as line shapes in the wing regions of water vapor lines are difficult to characterize. The measurements are required for air pollution studies using a CO laser, to find the differential absorption at the wavelengths in question due to atmospheric constituents other than water vapor. The design and performance of the optoacoustical detector are presented. Effects of absorption by ambient NO are considered, and the fixed-frequency discretely tunable CO laser is found suitable for monitoring urban NO concentrations in a fairly dry climate, using the water vapor absorption data obtained in the study.

  9. Optimum design of a multi-stage dye-laser amplifier pumped with Cu-vapor lasers

    International Nuclear Information System (INIS)

    Maeda, Mitsuo; Uchiumi, Michihiro

    1990-01-01

    A numerical simulation code, based on the one-dimensional photon transport equation, was developed and analyzed to evaluate the performances of Rhodamine 6G dye laser amplifiers pumped with Cu-vapor lasers. The upper singlet-state absorption played an important role to determine the efficiency. The simulation code was applied to optimize a multi-stage amplifier system with a pulsed or a CW dye-laser oscillator. The analytical results gave a useful guideline to design a high-power pulsed dye-laser system for atomic uranium enrichment. (author)

  10. Density determination in the TEXTOR boundary layer by laser-ablated fast lithium atoms

    International Nuclear Information System (INIS)

    Pospieszczyk, A.; Ross, G.G.

    1988-01-01

    A method is presented which allows a determination of electron density profiles in the plasma boundary of a fusion device up to some 10 13 cm -3 within about 100 μs. For this purpose, the complete attenuation of an injected lithium beam is determined by measuring its optical emission profile. The beam is generated by a ruby laser, which ablates small portions of a LiF coating with a thickness of about 1000 A from the rear side of a glass substrate. The produced lithium atoms have velocities of 1 x 10 6 cm/s and can penetrate into the plasma until n/sub e/ x l ≅1 x 10 13 cm -2 . For the measurement of the optical emission profile of the excited lithium atoms, a silicon photodiode array camera is used. The emission profile is then converted into an electron density profile with the help of the ionization rate for lithium atoms by electron impact

  11. Quantum state population transfer of lithium atoms induced by frequency-chirped laser pulses

    International Nuclear Information System (INIS)

    Ma Huanqiang; Zhang Xianzhou; Jia Guangrui; Zhang Yonghui; Jiang Lijuan

    2011-01-01

    Using the time-dependent multilevel approach (TDMA) and B-splines function, we have calculated the five quantum state population transfer of rydberg lithium atoms. We also analyse the influence of the four major parameters of the frequency-chirped laser pulses field on transition. The result shows that the population can be completely transferred to the target state by changing the parameters of the laser pulse and achieve manual controls to a certain degree. (authors)

  12. Laser pulse propagation in a meter scale rubidium vapor/plasma cell in AWAKE experiment

    CERN Document Server

    Joulaei, Atefeh; Berti, Nicolas; Kasparian, Jerome; Mirzanejhad, Saeed; Muggli, Patric

    2016-01-01

    We present the results of numerical studies of laser pulse propagating in a 3.5 cm Rb vapor cell in the linear dispersion regime by using a 1D model and a 2D code that has been modified for our special case. The 2D simulation finally aimed at finding laser beam parameters suitable to make the Rb vapor fully ionized to obtain a uniform, 10 m-long, at least 1 mm in radius plasma in the next step for the AWAKE experiment.

  13. THERAPY OF SKIN VASCULAR MALFORMATIONS USING COPPER VAPOR LASER AND PULSED DYE LASER

    Directory of Open Access Journals (Sweden)

    Svetlana V. Klyuchareva

    2018-01-01

    Full Text Available Aim. Comparison of effectiveness of the application of copper vapor laser (CVL and pulsed dye laser (PDL in clinical practice. Development of choice criteria of the more effective method of treatment.Materials and methods. The clinical data using CVL and PDL in the treatment of skin vascular malformations are presented. The treatment gave good results in removing of dysplastic skin vessels in 2 and 6 months. The treatment was not painful, and patients did not need general and local anesthesia. The results were presented concerning computer modeling of selective heating of vessels in tissue with CVL and PDL radiation. These results allowed to determine the depth of location and dimensions of vessels for selective and secure removing and the safe dosage ranges were found.Results. On the base of the calculated data, one could conclude that the mode of heating of dysplastic vessels with micropulse series of CVL is more safe and effective than the mode of powerful short pulses in the case of PDL.

  14. Synthesis of single walled carbon nanotubes by dual laser vaporization

    CSIR Research Space (South Africa)

    Moodley, MK et al.

    2006-02-27

    Full Text Available Single-walled carbon nanotubes were synthesised by the laser vaporisation of graphite composite targets in a tube furnace. Two pulsed Nd:YAG lasers operating at fundamental (1 064 nm) and 2nd harmonic (532 nm) were combined, focused and evaporated...

  15. High-speed off-axis holographic cinematography with a copper-vapor-pumped dye laser.

    Science.gov (United States)

    Lauterborn, W; Judt, A; Schmitz, E

    1993-01-01

    A series of coherent light pulses is generated by pumping a dye laser with the pulsed output of a copper-vapor laser at rates of as much as 20 kHz. Holograms are recorded at this pulse rate on a rotating holographic plate. This technique of high-speed holographic cinematography is demonstrated by viewing the bubble filaments that appear in water under the action of a sound field of high intensity.

  16. Spectral control of an alexandrite laser for an airborne water-vapor differential absorption lidar system

    Science.gov (United States)

    Ponsardin, Patrick; Grossmann, Benoist E.; Browell, Edward V.

    1994-01-01

    A narrow-linewidth pulsed alexandrite laser has been greatly modified for improved spectral stability in an aircraft environment, and its operation has been evaluated in the laboratory for making water-vapor differential absorption lidar measurements. An alignment technique is described to achieve the optimum free spectral range ratio for the two etalons inserted in the alexandrite laser cavity, and the sensitivity of this ratio is analyzed. This technique drastically decreases the occurrence of mode hopping, which is commonly observed in a tunable, two-intracavity-etalon laser system. High spectral purity (greater than 99.85%) at 730 nm is demonstrated by the use of a water-vapor absorption line as a notch filter. The effective cross sections of 760-nm oxygen and 730-nm water-vapor absorption lines are measured at different pressures by using this laser, which has a finite linewidth of 0.02 cm(exp -1) (FWHM). It is found that for water-vapor absorption linewidths greater than 0.04 cm(exp -1) (HWHM), or for altitudes below 10 km, the laser line can be considered monochromatic because the measured effective absorption cross section is within 1% of the calculated monochromatic cross section. An analysis of the environmental sensitivity of the two intracavity etalons is presented, and a closed-loop computer control for active stabilization of the two intracavity etalons in the alexandrite laser is described. Using a water-vapor absorption line as a wavelength reference, we measure a long-term frequency drift (approximately 1.5 h) of less than 0.7 pm in the laboratory.

  17. Effect of the background radiation of a copper vapor laser with an unstable resonator on dye lasing

    Energy Technology Data Exchange (ETDEWEB)

    Elaev, V F; Mirza, S M; Sukhanov, V B; Troitskii, V O; Soldatov, A N

    1986-05-01

    Results of an experimental study of the emission divergence of a copper vapor laser with an unstable resonator are reported. It is shown that a copper vapor laser beam can be conveniently treated as a pair of components with a divergence higher or lower than a certain optimal value; the percent ratio of the components varies with the pulse repetition frequency. In the case where a copper vapor laser is used to pump a dye laser, the contribution of the component with the higher divergence to dye lasing does not exceed 1 percent. 7 references.

  18. Laser-assisted chemical vapor deposition setup for fast synthesis of graphene patterns

    Science.gov (United States)

    Zhang, Chentao; Zhang, Jianhuan; Lin, Kun; Huang, Yuanqing

    2017-05-01

    An automatic setup based on the laser-assisted chemical vapor deposition method has been developed for the rapid synthesis of graphene patterns. The key components of this setup include a laser beam control and focusing unit, a laser spot monitoring unit, and a vacuum and flow control unit. A laser beam with precision control of laser power is focused on the surface of a nickel foil substrate by the laser beam control and focusing unit for localized heating. A rapid heating and cooling process at the localized region is induced by the relative movement between the focalized laser spot and the nickel foil substrate, which causes the decomposing of gaseous hydrocarbon and the out-diffusing of excess carbon atoms to form graphene patterns on the laser scanning path. All the fabrication parameters that affect the quality and number of graphene layers, such as laser power, laser spot size, laser scanning speed, pressure of vacuum chamber, and flow rates of gases, can be precisely controlled and monitored during the preparation of graphene patterns. A simulation of temperature distribution was carried out via the finite element method, providing a scientific guidance for the regulation of temperature distribution during experiments. A multi-layer graphene ribbon with few defects was synthesized to verify its performance of the rapid growth of high-quality graphene patterns. Furthermore, this setup has potential applications in other laser-based graphene synthesis and processing.

  19. Ablation of biological tissues by radiation of strontium vapor laser

    Energy Technology Data Exchange (ETDEWEB)

    Soldatov, A. N., E-mail: general@tic.tsu.ru; Vasilieva, A. V., E-mail: anita-tomsk@mail.ru [National Research Tomsk State University, Lenin ave., 36, 634050, Tomsk (Russian Federation)

    2015-11-17

    A two-stage laser system consisting of a master oscillator and a power amplifier based on sources of self- contained transitions in pairs SrI and SrII has been developed. The radiation spectrum contains 8 laser lines generating in the range of 1 – 6.45 μm, with a generation pulse length of 50 – 150 ns, and pulse energy of ∼ 2.5 mJ. The divergence of the output beam was close to the diffraction and did not exceed 0.5 mrad. The control range of the laser pulse repetition rate varied from 10 to 15 000 Hz. The given laser system has allowed to perform ablation of bone tissue samples without visible thermal damage.

  20. Second-harmonic generation in atomic vapor with picosecond laser pulses

    International Nuclear Information System (INIS)

    Kim, D.; Mullin, C.S.; Shen, Y.R.

    1997-01-01

    Picosecond laser pulses were used to study the highly forbidden resonant second-harmonic generation (SHG) in potassium vapor. The input intensity dependence, vapor density dependence, buffer-gas pressure dependence, and spatial profile of the SHG were measured. A pump - probe experiment was conducted to probe the time dependence of the SHG signal. The experimental results can be understood from an ionization-initiated dc-field-induced SHG model. A theory of a dc-field-induced SHG model is developed that takes into account the time development of the dc electric field in detail. This temporal buildup of the dc field along with transient coherent excitation between two-photon-allowed transitions can explain the experimental results quantitatively, including the previous vapor SHG results with nanosecond laser pulses. copyright 1997 Optical Society of America

  1. Vertical-cavity surface-emitting laser vapor sensor using swelling polymer reflection modulation

    DEFF Research Database (Denmark)

    Ansbæk, Thor; Nielsen, Claus Højgård; Dohn, Søren

    2012-01-01

    Vapor detection using a low-refractive index polymer for reflection modulation of the top mirror in a vertical-cavity surface-emitting laser (VCSEL) is demonstrated. The VCSEL sensor concept presents a simple method to detect the response of a sensor polymer in the presence of volatile organic...

  2. Modeling CO2 laser ablation impulse of polymers in vapor and plasma regimes

    International Nuclear Information System (INIS)

    Sinko, John E.; Phipps, Claude R.

    2009-01-01

    An improved model for CO 2 laser ablation impulse in polyoxymethylene and similar polymers is presented that describes the transition effects from the onset of vaporization to the plasma regime in a continuous fashion. Several predictions are made for ablation behavior.

  3. Description of a laser vaporization source and a supersonic cluster beam apparatus

    International Nuclear Information System (INIS)

    Doverstaal, M.; Lindgren, B.; Sassenberg, U.; Yu, H.

    1993-11-01

    Laser vaporization of an appropriate target and recent developments in molecular beam technology have now made it possible to produce supersonic cluster beams of virtually any element in the periodic table. This paper describes the design and principles of a cluster source combined with a time of flight mass spectrometer built for reaction experiments and spectroscopic investigations at Stockholm University

  4. Polymer-coated vertical-cavity surface-emitting laser diode vapor sensor

    DEFF Research Database (Denmark)

    Ansbæk, Thor; Nielsen, Claus Højgaard; Larsen, Niels Bent

    2010-01-01

    We report a new method for monitoring vapor concentration of volatile organic compounds using a vertical-cavity surface-emitting laser (VCSEL). The VCSEL is coated with a polymer thin film on the top distributed Bragg reflector (DBR). The analyte absorption is transduced to the electrical domain ...

  5. Damage threshold of lithium niobate crystal under single and multiple femtosecond laser pulses: theoretical and experimental study

    International Nuclear Information System (INIS)

    Meng, Qinglong; Zhang, Bin; Zhong, Sencheng; Zhu, Liguo

    2016-01-01

    The damage threshold of lithium niobate crystal under single and multiple femtosecond laser pulses has been studied theoretically and experimentally. Firstly, the model for the damage threshold prediction of crystal materials based on the improved rate equation has been proposed. Then, the experimental measure method of the damage threshold of crystal materials has been given in detail. On the basis, the variation of the damage threshold of lithium niobate crystal with the pulse duration has also been analyzed quantitatively. Finally, the damage threshold of lithium niobate crystal under multiple laser pulses has been measured and compared to the theoretical results. The results show that the transmittance of lithium niobate crystal is almost a constant when the laser pulse fluence is relative low, whereas it decreases linearly with the increase in the laser pulse fluence below the damage threshold. The damage threshold of lithium niobate crystal increases with the increase in the duration of the femtosecond laser pulse. And the damage threshold of lithium niobate crystal under multiple laser pulses is obviously lower than that irradiated by a single laser pulse. The theoretical data fall in good agreement with the experimental results. (orig.)

  6. Contamination spike simulation and measurement in a clean metal vapor laser

    International Nuclear Information System (INIS)

    Lin, C.E.; Yang, C.Y.

    1990-01-01

    This paper describes a new method for the generation of contamination-induced voltage spikes in a clean metal vapor laser. The method facilitates the study of the characteristics of this troublesome phenomenon in laser systems. Analysis of these artificially generated dirt spikes shows that the breakdown time of the laser tube is increased when these spike appear. The concept of a Townsend discharge is used to identify the parameter which changes the breakdown time of the discharges. The residual ionization control method is proposed to generate dirt spikes in a clean laser. Experimental results show that a wide range of dirt spike magnitudes can be obtained by using the proposed method. The method provides easy and accurate control of the magnitude of the dirt spike, and the laser tube does not become polluted. Results based on the measurements can be used in actual laser systems to monitor the appearance of dirt spikes and thus avoid the danger of thyratron failure

  7. Perspectives of transurethral robotic laser resection of the prostate: vaporization and coagulation effects with the Nd:YAG laser

    Science.gov (United States)

    Ho, Gideon; Teo, Ming Y.; Kwoh, Chee K.; Ng, Wan S.; Cheng, Wai S.

    2000-05-01

    A longer operating time and steeper learning curve in mastering the techniques for transurethral laser resection of the prostate are the main problems faced by surgeons compared to standard transurethral resection of the prostate (TURP). However, these disadvantages can be solved with the introduction of a treatment modality designed and developed based on an integrated system of computer, robotics and laser technology. In vitro experiments were carried out to determine variables affecting the vaporization and coagulation lesions, in order to identify the parameters that could optimize this modality. Human cadaveric prostate and fresh chicken breast tissues were irradiated with different parameters using continuous wave Nd:YAG laser fiber in contact with the tissue. The effects of irrigant flowrate, fiber/tissue angle of inclination, number of passes, direction, speed and power of lase on the volume of tissue vaporized and coagulated, were assessed. A non-contact optical coordinate measuring machine was used to measure the depth and width of the vaporized and coagulated lesion. Results reveal that for each directional vaporization path (forward, clockwise and counter-clockwise), power and speed of lase are the most significant parameters influencing the volume of the vaporized and coagulated lesion. Optimized values of the power and speed of lase at 100 W and 1 - 3 mm/s respectively were obtained from the experiments when the tissues were irradiated in the forward, clockwise and counter-clockwise directions. It was concluded from our study to quantify tissue removal and damage, optimized values of irradiation power and speed could be obtained and implemented in the procedure of transurethral robotic laser resection of the prostate.

  8. Investigation of the lasing of dyes under copper vapor laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Danilova, V I; Kopylova, T N; Maier, G V; Masarnovskii, L V; Soldatov, A N; Sukhanov, V B

    1980-10-01

    The lasing characteristics of dyes pumped by copper vapor laser radiation are investigated in order to determine the optimal energetic parameters of the dye-laser system. Expressions are derived for the yields of stimulated emission from dye molecules, and it is shown that the most effective means of improving the lasing characteristics of rhodamine dye solutions is by the modification of intermolecular interactions, in part by the use of multicomponent solutions. Results are then presented of experimental measurements of the emission intensities of combinations of rhodamine dyes irradiated by the 5106-A line of a copper vapor laser. An increase in the lasing efficiency of the acceptor molecule is found for all the dye pairs investigated, with even greater emission intensities observed for multicomponent dye mixtures when the mixtures were pumped transversely. Under longitudinal pumping, improvements in lasing efficiency were obtained only for mixtures of rhodamine 6 Zh with cresil violet.

  9. Optimized path planning for soft tissue resection via laser vaporization

    Science.gov (United States)

    Ross, Weston; Cornwell, Neil; Tucker, Matthew; Mann, Brian; Codd, Patrick

    2018-02-01

    Robotic and robotic-assisted surgeries are becoming more prevalent with the promise of improving surgical outcomes through increased precision, reduced operating times, and minimally invasive procedures. The handheld laser scalpel in neurosurgery has been shown to provide a more gentle approach to tissue manipulation on or near critical structures over classical tooling, though difficulties of control have prevented large scale adoption of the tool. This paper presents a novel approach to generating a cutting path for the volumetric resection of tissue using a computer-guided laser scalpel. A soft tissue ablation simulator is developed and used in conjunction with an optimization routine to select parameters which maximize the total resection of target tissue while minimizing the damage to surrounding tissue. The simulator predicts the ablative properties of tissue from an interrogation cut for tuning and simulates the removal of a tumorous tissue embedded on the surface of healthy tissue using a laser scalpel. We demonstrate the ability to control depth and smoothness of cut using genetic algorithms to optimize the ablation parameters and cutting path. The laser power level, cutting rate and spacing between cuts are optimized over multiple surface cuts to achieve the desired resection volumes.

  10. Laser-produced lithium plasma as a narrow-band extended ultraviolet radiation source for photoelectron spectroscopy.

    Science.gov (United States)

    Schriever, G; Mager, S; Naweed, A; Engel, A; Bergmann, K; Lebert, R

    1998-03-01

    Extended ultraviolet (EUV) emission characteristics of a laser-produced lithium plasma are determined with regard to the requirements of x-ray photoelectron spectroscopy. The main features of interest are spectral distribution, photon flux, bandwidth, source size, and emission duration. Laser-produced lithium plasmas are characterized as emitters of intense narrow-band EUV radiation. It can be estimated that the lithium Lyman-alpha line emission in combination with an ellipsoidal silicon/molybdenum multilayer mirror is a suitable EUV source for an x-ray photoelectron spectroscopy microscope with a 50-meV energy resolution and a 10-mum lateral resolution.

  11. Theoretical analyses of an injection-locked diode-pumped rubidium vapor laser.

    Science.gov (United States)

    Cai, He; Gao, Chunqing; Liu, Xiaoxu; Wang, Shunyan; Yu, Hang; Rong, Kepeng; An, Guofei; Han, Juhong; Zhang, Wei; Wang, Hongyuan; Wang, You

    2018-04-02

    Diode-pumped alkali lasers (DPALs) have drawn much attention since they were proposed in 2001. The narrow-linewidth DPAL can be potentially applied in the fields of coherent communication, laser radar, and atomic spectroscopy. In this study, we propose a novel protocol to narrow the width of one kind of DPAL, diode-pumped rubidium vapor laser (DPRVL), by use of an injection locking technique. A kinetic model is first set up for an injection-locked DPRVL with the end-pumped configuration. The laser tunable duration is also analyzed for a continuous wave (CW) injection-locked DPRVL system. Then, the influences of the pump power, power of a master laser, and reflectance of an output coupler on the output performance are theoretically analyzed. The study should be useful for design of a narrow-linewidth DPAL with the relatively high output.

  12. Laser optical pumping of sodium and lithium atom beams

    International Nuclear Information System (INIS)

    Cusma, J.T.

    1983-01-01

    The method of optical pumping with a continuous wave dye laser has been used to produce beams of polarized 23 Na atoms and polarized 6 Li atoms. Optical pumping of a 23 Na atom beam using either a multimode dye laser or a single frequency dye laser with a double passed acousto-optic modulator results in electron spin polarizations of 0.70-0.90 and nuclear spin polarizations of 0.75-0.90. Optical pumping of a 6 Li atom beam using a single frequency dye laser either with an acousto-optic modulator or with Doppler shift pumping results in electron spin polarizations of 0.77-0.95 and nuclear spin polarizations greater than 0.90. The polarization of the atom beam is measured using either the laser induced fluorescence in an intermediate magnetic field or a 6-pole magnet to determine the occupation probabilities of the ground hyperfine sublevels following optical pumping. The results of the laser optical pumping experiments agree with the results of a rate equation analysis of the optical pumping process which predicts that nearly all atoms are transferred into a single sublevel for our values of laser intensity and interaction time. The use of laser optical pumping in a polarized ion source for nuclear scattering experiments is discussed. The laser optical pumping method provides a means of constructing an intense source of polarized Li and Na ions

  13. GreenLight laser vs diode laser vaporization of the prostate: 3-year results of a prospective nonrandomized study.

    Science.gov (United States)

    Guo, Sanwei; Müller, Georg; Bonkat, Gernot; Püschel, Heike; Gasser, Thomas; Bachmann, Alexander; Rieken, Malte

    2015-04-01

    Laser vaporization of the prostate is one of the alternatives to transurethral resection of the prostate. Short-term studies report a comparable outcome after laser vaporization with the 532 nm 120-W GreenLight high-performance system (HPS) laser and the 980 nm 200 W high-intensity diode (diode) laser. In this study, we analyzed the intermediate-term results of both techniques. From January 2007 to January 2008, 112 consecutive patients with symptomatic benign prostate enlargement were nonrandomly assigned to treatment with the GreenLight laser or the diode laser. Perioperative parameters, postoperative functional outcome, complications, and the reoperation rate at 3 years were analyzed. Improvement of voiding symptoms (International Prostate Symptom Score, quality-of-life) and micturition parameters (maximum flow rate, postvoid residual volume) showed no significant difference between the HPS group and the diode group. A significantly higher reoperation rate was observed in the diode group in comparison to the HPS group (37.5% vs 8.9%, p=0.0003) due to obstructive necrotic tissue (16.1% vs 0%, p=0.0018), bladder neck stricture (16.1% vs 1.8%, p=0.008), and persisting or recurrent adenoma (5.4% vs 7.1%, p=0.70), respectively. Both lasers lead to comparable improvement of voiding parameters and micturition symptoms. Treatment with the 200 W diode laser led to a significantly higher reoperation rate, which might be attributed to a higher degree of coagulation necrosis. Thus, a careful clinical application of this diode laser type is warranted.

  14. The reaction of lithium metal vapor with single walled carbon nanotubes of large diameters

    Czech Academy of Sciences Publication Activity Database

    Kalbáč, Martin; Kavan, Ladislav; Dunsch, L.

    2009-01-01

    Roč. 246, 11-12 (2009), s. 2428-2431 ISSN 0370-1972 R&D Projects: GA AV ČR IAA400400911; GA AV ČR KAN200100801; GA AV ČR IAA400400804; GA ČR GC203/07/J067; GA MŠk LC510 Institutional research plan: CEZ:AV0Z40400503 Keywords : lithium * single walled carbon nanotubes * Raman spectroscopy Subject RIV: CG - Electrochemistry Impact factor: 1.150, year: 2009

  15. Laser remote sensing of water vapor: Raman lidar development

    International Nuclear Information System (INIS)

    Goldsmith, J.E.M.; Lapp, M.; Bisson, S.E.; Melfi, S.H.; Whiteman, D.N.; Ferrare, R.A.; Evans, K.D.

    1994-01-01

    The goal of this research is the development of a critical design for a Raman lidar system optimized to match ARM Program needs for profiling atmospheric water vapor at CART sites. This work has emphasized the development of enhanced daytime capabilities using Raman lidar techniques. This abstract touches briefly on the main components of the research program, summarizing results of the efforts. A detailed Raman lidar instrument model has been developed to predict the daytime and nighttime performance capabilities of Raman lidar systems. The model simulates key characteristics of the lidar system, using realistic atmospheric profiles, modeled background sky radiance, and lidar system parameters based on current instrument capabilities. The model is used to guide development of lidar systems based on both the solar-blind concept and the narrowband, narrow field-of-view concept for daytime optimization

  16. Vapor-phase infrared laser spectroscopy: from gas sensing to forensic urinalysis.

    Science.gov (United States)

    Bartlome, Richard; Rey, Julien M; Sigrist, Markus W

    2008-07-15

    Numerous gas-sensing devices are based on infrared laser spectroscopy. In this paper, the technique is further developed and, for the first time, applied to forensic urinalysis. For this purpose, a difference frequency generation laser was coupled to an in-house-built, high-temperature multipass cell (HTMC). The continuous tuning range of the laser was extended to 329 cm(-1) in the fingerprint C-H stretching region between 3 and 4 microm. The HTMC is a long-path absorption cell designed to withstand organic samples in the vapor phase (Bartlome, R.; Baer, M.; Sigrist, M. W. Rev. Sci. Instrum. 2007, 78, 013110). Quantitative measurements were taken on pure ephedrine and pseudoephedrine vapors. Despite featuring similarities, the vapor-phase infrared spectra of these diastereoisomers are clearly distinguishable with respect to a vibrational band centered at 2970.5 and 2980.1 cm(-1), respectively. Ephedrine-positive and pseudoephedrine-positive urine samples were prepared by means of liquid-liquid extraction and directly evaporated in the HTMC without any preliminary chromatographic separation. When 10 or 20 mL of ephedrine-positive human urine is prepared, the detection limit of ephedrine, prohibited in sports as of 10 microg/mL, is 50 or 25 microg/mL, respectively. The laser spectrometer has room for much improvement; its potential is discussed with respect to doping agents detection.

  17. The disintegration and vaporization of plastic targets irradiated by high-power laser pulses

    International Nuclear Information System (INIS)

    Greig, J.R.; Pechacek, R.E.

    1977-01-01

    We have studied the disintegration of polyethylene and polystyrene targets irradiated by 100-J 40-nsec Nd/glass laser pulses. At power densities of approximately-less-than10 12 W/cm 2 relatively massive targets (6 x 10 -5 to 5 x 10 -4 cm 3 ) are totally disintegrated to produce finely divided target material and un-ionized vapor. Both the size of the target and the presence or absence of a laser prepulse strongly influence the proportions of finely divided target material and un-ionized vapor, especially within the first few microseconds after peak laser power. This disintegration is always preceded by the emission of a hot fully ionized plasma, but only 1% of the target material is contained in the hot plasma. Typically, (1--3) x 10 19 atoms of un-ionized vapor are released as a slowly expanding (vapprox.10 5 cm/sec) cold dense gas cloud (n/sub o/>10 19 cm -3 ) surrounding the initial target position. This cloud of target material has subsequently been heated by absorption of a 300-J 100-nsec CO 2 laser pulse to produce an approximately fully ionized plasma

  18. Conceptual design considerations and neutronics of lithium fall laser fusion target chambers

    International Nuclear Information System (INIS)

    Meier, W.R.; Thomson, W.B.

    1978-01-01

    Atomics International and Lawrence Livermore Laboratory are involved in the conceptual design of a laser fusion power plant incorporating the lithium fall target chamber. In this paper we discuss some of the more important design considerations for the target chamber and evaluate its nuclear performance. Sizing and configuration of the fall, hydraulic effects, and mechanical design considerations are addressed. The nuclear aspects examined include tritium breeding, energy deposition, and radiation damage

  19. Conceptual design considerations and neutronics of lithium fall laser target chambers

    International Nuclear Information System (INIS)

    Meier, W.R.; Thomson, W.B.

    1978-01-01

    Atomics International and Lawrence Livermore Laboratory are involved in the conceptual design of a laser fusion power plant incorporating the lithium fall target chamber. In this paper we discuss some of the more important design considerations for the target chamber and evaluate its nuclear performance. Sizing and configuration of the fall, hydraulic effects, and mechanical design considerations are addressed. The nuclear aspects examined include tritium breeding, energy deposition, and radiation damage

  20. Laser diagnostics of the energy spectrum of Rydberg states of the lithium-7 atom

    Energy Technology Data Exchange (ETDEWEB)

    Zelener, B. B., E-mail: bobozel@mail.ru; Saakyan, S. A.; Sautenkov, V. A.; Manykin, E. A.; Zelener, B. V.; Fortov, V. E. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2015-12-15

    The spectra of excited lithium-7 atoms prepared in a magneto-optical trap are studied using a UV laser. The laser diagnostics of the energy of Rydberg atoms is developed based on measurements of the change in resonance fluorescence intensity of ultracold atoms as the exciting UV radiation frequency passes through the Rydberg transition frequency. The energies of various nS configurations are obtained in a broad range of the principal quantum number n from 38 to 165. The values of the quantum defect and ionization energy obtained in experiments and predicted theoretically are discussed.

  1. Broadband Optical Active Waveguides Written by Femtosecond Laser Pulses in Lithium Fluoride

    International Nuclear Information System (INIS)

    Chiamenti, Ismael; Costa, Larissa N. da; Kalinowski, Hypolito J.; Bonfigli, Francesca; Montereali, Rosa Maria; Gomes Anderson, S. L.

    2014-01-01

    Broadband waveguiding through light-emitting strips directly written in a blank lithium fluoride crystal with a femtosecond laser is reported. Light guiding was observed at several optical wavelengths, from blue, 458 nm, to near-infrared, at 1550 nm. Visible photoluminescence spectra of the optically active F 2 and F 3 + color centers produced by the fs laser writing process were measured. The wavelength-dependent refractive index increase was estimated to be in the order of 10 −3 −10 −4 in the visible and near-infrared spectral intervals, which is consistent with the stable formation of point defects in LiF

  2. Broadband Optical Active Waveguides Written by Femtosecond Laser Pulses in Lithium Fluoride

    Science.gov (United States)

    Ismael, Chiamenti; Francesca, Bonfigli; Anderson, S. L. Gomes; Rosa, Maria Montereali; Larissa, N. da Costa; Hypolito, J. Kalinowski

    2014-01-01

    Broadband waveguiding through light-emitting strips directly written in a blank lithium fluoride crystal with a femtosecond laser is reported. Light guiding was observed at several optical wavelengths, from blue, 458 nm, to near-infrared, at 1550 nm. Visible photoluminescence spectra of the optically active F2 and F3+ color centers produced by the fs laser writing process were measured. The wavelength-dependent refractive index increase was estimated to be in the order of 10-3-10-4 in the visible and near-infrared spectral intervals, which is consistent with the stable formation of point defects in LiF.

  3. New alternatives for laser vaporization of the prostate: experimental evaluation of a 980-, 1,318- and 1,470-nm diode laser device.

    Science.gov (United States)

    Wezel, Felix; Wendt-Nordahl, Gunnar; Huck, Nina; Bach, Thorsten; Weiss, Christel; Michel, Maurice Stephan; Häcker, Axel

    2010-04-01

    Several diode laser systems were introduced in recent years for the minimal-invasive surgical therapy of benign prostate enlargement. We investigated the ablation capacities, hemostatic properties and extend of tissue necrosis of different diode lasers at wavelengths of 980, 1,318 and 1,470 nm and compared the results to the 120 W GreenLight HPS laser. The laser devices were evaluated in an ex vivo model using isolated porcine kidneys. The weight difference of the porcine kidneys after 10 min of laser vaporization defined the amount of ablated tissue. Blood loss was measured in blood-perfused kidneys following laser vaporization. Histological examination was performed to assess the tissue effects. The side-firing 980 and 1,470 nm diode lasers displayed similar ablative capacities compared to the GreenLight HPS laser (n.s.). The 1,318-nm laser, equipped with a bare-ended fiber, reached a higher ablation rate compared to the other laser devices (each P laser with a bare-ended fiber reached the highest rate compared to the side-firing devices (each P diode lasers showed superior hemostatic properties compared to the GreenLight HPS laser (each P laser), respectively. The diode lasers offered similar ablative capacities and improved hemostatic properties compared to the 120 W GreenLight HPS laser in this experimental ex vivo setting. The higher tissue penetration of the diode lasers compared to the GreenLight HPS laser may explain improved hemostasis.

  4. Kinetics of laser pulse vaporization of uranium dioxide by mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, C.

    1981-11-01

    Safety analyses of nuclear reactors require knowledge of the evaporation behavior of UO/sub 2/ at temperatures well above the melting point of 3140 K. In this study, rapid transient heating of a small spot on a UO/sub 2/ specimen was accomplished by a laser pulse, which generates a surface temperature excursion. This in turn vaporizes the target surface and the gas expands into vacuum. The surface temperature transient was monitored by a fast-response automatic optical pyrometer. The maximum surface temperatures investigated range from approx. 3700 K to approx. 4300 K. A computer program was developed to simulate the laser heating process and calculate the surface temperature evolution. The effect of the uncertainties of the high temperature material properties on the calculation was included in a sensitivity study for UO/sub 2/ vaporization. The measured surface temperatures were in satisfactory agreements.

  5. Dual-axis vapor cell for simultaneous laser frequency stabilization on disparate optical transitions

    Science.gov (United States)

    Jayakumar, Anupriya; Plotkin-Swing, Benjamin; Jamison, Alan O.; Gupta, Subhadeep

    2015-07-01

    We have developed a dual-axis ytterbium (Yb) vapor cell and used it to simultaneously address the two laser cooling transitions in Yb at wavelengths 399 nm and 556 nm, featuring the disparate linewidths of 2π × 29 MHz and 2π × 182 KHz, respectively. By utilizing different optical paths for the two wavelengths, we simultaneously obtain comparable optical densities suitable for saturated absorption spectroscopy for both the transitions and keep both the lasers frequency stabilized over several hours. We demonstrate that by appropriate control of the cell temperature profile, two atomic transitions differing in relative strength across a large range of over three orders of magnitude can be simultaneously addressed, making the device adaptable to a variety of spectroscopic needs. We also show that our observations can be understood with a simple theoretical model of the Yb vapor.

  6. Dual-axis vapor cell for simultaneous laser frequency stabilization on disparate optical transitions

    Energy Technology Data Exchange (ETDEWEB)

    Jayakumar, Anupriya, E-mail: anupriya@uw.edu; Plotkin-Swing, Benjamin; Jamison, Alan O.; Gupta, Subhadeep [Department of Physics, University of Washington, P.O. Box 351560, Seattle, Washington 98195-1560 (United States)

    2015-07-15

    We have developed a dual-axis ytterbium (Yb) vapor cell and used it to simultaneously address the two laser cooling transitions in Yb at wavelengths 399 nm and 556 nm, featuring the disparate linewidths of 2π × 29 MHz and 2π × 182 KHz, respectively. By utilizing different optical paths for the two wavelengths, we simultaneously obtain comparable optical densities suitable for saturated absorption spectroscopy for both the transitions and keep both the lasers frequency stabilized over several hours. We demonstrate that by appropriate control of the cell temperature profile, two atomic transitions differing in relative strength across a large range of over three orders of magnitude can be simultaneously addressed, making the device adaptable to a variety of spectroscopic needs. We also show that our observations can be understood with a simple theoretical model of the Yb vapor.

  7. Theoretical investigation of output features of a diode-pumped rubidium vapor laser

    Science.gov (United States)

    Wang, You; Cai, He; Zhang, Wei; Xue, Liangping; Wang, Hongyuan; Han, Juhong

    2014-02-01

    In the recent years, diode-pumped alkali lasers (DPALs) have been paid many attentions because of their excellent performances. In fact, the characteristics of a DPAL strongly depend on the physical features of buffer gases. In this report, we selected a diode-pumped rubidium vapor laser (DPRVL), which is an important type among three common DPALs, to investigate how the characteristics of a DPRVL are affected by different conditions. The results signify that the population ratio of two excitation energy-levels are close to that corresponding to thermal equilibrium as the pressure of buffer gases and the temperature of a vapor cell become higher. It has been found that quenching of the upper levels cannot be simply ignored especially for the case of weak pump. The conclusions are thought to be helpful for the configuration design of an end-pumped DPAL.

  8. Optical emission spectroscopy of metal vapor dominated laser-arc hybrid welding plasma

    International Nuclear Information System (INIS)

    Ribic, B.; DebRoy, T.; Burgardt, P.

    2011-01-01

    During laser-arc hybrid welding, plasma properties affect the welding process and the weld quality. However, hybrid welding plasmas have not been systematically studied. Here we examine electron temperatures, species densities, and electrical conductivity for laser, arc, and laser-arc hybrid welding using optical emission spectroscopy. The effects of arc currents and heat source separation distances were examined because these parameters significantly affect weld quality. Time-average plasma electron temperatures, electron and ion densities, electrical conductivity, and arc stability decrease with increasing heat source separation distance during hybrid welding. Heat source separation distance affects these properties more significantly than the arc current within the range of currents considered. Improved arc stability and higher electrical conductivity of the hybrid welding plasma result from increased heat flux, electron temperatures, electron density, and metal vapor concentrations relative to arc or laser welding.

  9. High power uv metal vapor ion lasers pumped by thermal energy charge exchange

    International Nuclear Information System (INIS)

    Kan, T.

    1975-01-01

    The requirement for efficient and scalable laser sources for laser isotope separation (LIS) has recently been brought into sharp focus. The lack of suitable coherent sources is particularly severe in the uv, a spectral region of interest for more efficient and advanced isotope separation schemes. This report explores the general class of metal vapor ion lasers pumped by thermal energy charge exchange (TECX) as possible scalable coherent sources for LIS with the following potential characteristics: (1) availability of discrete wavelengths spanning the wavelength region between 2000 A less than lambda less than 8000 A, (2) pulsed or cw operation in the multi-kilowatt average power levels, (3) overall device efficiencies approaching one percent, and (4) the engineering of practical laser devices using relatively benign electron beam technology. (U.S.)

  10. High intensity vacuum ultraviolet and extreme ultraviolet production by noncollinear mixing in laser vaporized media

    Energy Technology Data Exchange (ETDEWEB)

    Todt, Michael A.; Albert, Daniel R.; Davis, H. Floyd, E-mail: hfd1@cornell.edu [Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-1301 (United States)

    2016-06-15

    A method is described for generating intense pulsed vacuum ultraviolet (VUV) and extreme ultraviolet (XUV) laser radiation by resonance enhanced four-wave mixing of commercial pulsed nanosecond lasers in laser vaporized mercury under windowless conditions. By employing noncollinear mixing of the input beams, the need of dispersive elements such as gratings for separating the VUV/XUV from the residual UV and visible beams is eliminated. A number of schemes are described, facilitating access to the 9.9–14.6 eV range. A simple and convenient scheme for generating wavelengths of 125 nm, 112 nm, and 104 nm (10 eV, 11 eV, and 12 eV) using two dye lasers without the need for dye changes is described.

  11. Continuous Water Vapor Mass Flux and Temperature Measurements in a Model Scramjet Combustor Using a Diode Laser Sensor

    National Research Council Canada - National Science Library

    Upschulte, B. L; Miller, M. F; Allen, M. G; Jackson, K; Gruber, M; Mathur, T

    1998-01-01

    A sensor for simultaneous measurements of water vapor density, temperature and velocity has been developed based on absorption techniques using room temperature diode lasers (InGaAsP) operating at 1.31 micrometers...

  12. A review of laser electrode processing for development and manufacturing of lithium-ion batteries

    Science.gov (United States)

    Pfleging, Wilhelm

    2018-02-01

    Laser processes for cutting, annealing, structuring, and printing of battery materials have a great potential in order to minimize the fabrication costs and to increase the electrochemical performance and operational lifetime of lithium-ion cells. Hereby, a broad range of applications can be covered such as micro-batteries, mobile applications, electric vehicles, and stand-alone electric energy storage devices. Cost-efficient nanosecond (ns)-laser cutting of electrodes was one of the first laser technologies which were successfully transferred to industrial high-energy battery production. A defined thermal impact can be useful in electrode manufacturing which was demonstrated by laser annealing of thin-film electrodes for adjusting of battery active crystalline phases or by laser-based drying of composite thick-film electrodes for high-energy batteries. Ultrafast or ns-laser direct structuring or printing of electrode materials is a rather new technical approach in order to realize three-dimensional (3D) electrode architectures. Three-dimensional electrode configurations lead to a better electrochemical performance in comparison to conventional 2D one, due to an increased active surface area, reduced mechanical tensions during electrochemical cycling, and an overall reduced cell impedance. Furthermore, it was shown that for thick-film composite electrodes an increase of electrolyte wetting could be achieved by introducing 3D micro-/nano-structures. Laser structuring can turn electrodes into superwicking. This has a positive impact regarding an increased battery lifetime and a reliable battery production. Finally, laser processes can be up-scaled in order to transfer the 3D battery concept to high-energy and high-power lithium-ion cells.

  13. Raman spectral features of single walled carbon nanotubes synthesized by laser vaporization

    CSIR Research Space (South Africa)

    Moodley, MK

    2006-07-05

    Full Text Available synthesized boxshadowdwnSemi-conductor tubes were favoured boxshadowdwnImproved crystallinity as indicated by narrower line- widths. Thank You Acknowledgements to the CSIR NLC for support on carbon nanotube research ... www.csir.co.za Experimental……..cont. Experimental parameters • two laser combined and vaporize a composite target • target in a tube furnace in continuous flow of Argon • temperature kept at 1000 OC • Ar flow of 200 sccm • Pressure at 375 Torr...

  14. Production of pulsed atomic oxygen beams via laser vaporization methods

    International Nuclear Information System (INIS)

    Brinza, D.E.; Coulter, D.R.; Liang, R.H.; Gupta, A.

    1987-01-01

    Energetic pulsed atomic oxygen beams were generated by laser-driven evaporation of cryogenically frozen ozone/oxygen films and thin films of indium-tin oxide (ITO). Mass and energy characterization of beams from the ozone/oxygen films were carried out by mass spectrometry. The peak flux, found to occur at 10 eV, is estimated from this data to be 3 x 10(20) m(-2) s(-1). Analysis of the time-of-flight data indicates a number of processes contribute to the formation of the atomic oxygen beam. The absence of metastable states such as the 2p(3) 3s(1) (5S) level of atomic oxygen blown off from ITO films is supported by the failure to observe emission at 777.3 nm from the 2p(3) 3p(1) (5P/sub J/) levels. Reactive scattering experiments with polymer film targets for atomic oxygen bombardment are planned using a universal crossed molecular beam apparatus

  15. High-energy laser-assisted imaging through vaporizing aerosols

    International Nuclear Information System (INIS)

    Zardecki, A.; Gerstl, S.A.W.

    1988-02-01

    The degradation of image quality due to multiple scattering in a turbid medium is analyzed various conditions of illumination. The emphasis is on the forward-peaked multiple scattering effects, which can adequately be described by the small-angle approximation. In the case of incoherent illumination, the modulation transfer function (MTF) can be given explicity both in the low- and high-frequency limits. For scattering with smaller degree of anisotropy, the MTF should be imputed numerically by considering numerical by considering solutions to the equation of radiative transfer with a line or point source. As the beam power increases, the turbid medium becomes modified by its interactions with the beam, thus affecting the image resolution. In this nonlinear transport regime (flux levels of the order of 10 6 Wcm 2 and higher) the propagation leads actually to beam narrowing. In the context of the imaging problem, an apparent paradosical situation in which the image of a point source narrows down as the high-energy laser (HEL) beam propagates is discussed. 14 refs., 12 figs

  16. The Laser Damage Threshold for Materials and the Relation Between Solid-Melt and Melt-Vapor Interface Velocities

    International Nuclear Information System (INIS)

    Khalil, Osama Mostafa

    2010-01-01

    Numerous experiments have demonstrated and analytic theories have predicted that there is a threshold for pulsed laser ablation of a wide range of materials. Optical surface damage threshold is a very complex and important application of high-power lasers. Optical damage may also be considered to be the initial phase of laser ablation. In this work it was determined the time required and the threshold energy of a layer of thickness to heat up. We used the Finite Difference method to simulate the process of laser-target interaction in three cases. Namely, the case before melting begins using a continuous wave (c.w) laser source and a pulsed laser source, the case after the first change of state (from solid to melt), and the case after the second change of state (from melt to vapor). And also study the relation between the solid-melt and melt-vapor interface velocities to have a commonsense of the laser ablation process.

  17. Near-field-optical-microscopy studies of micro-modifications caused by femtosecond laser irradiation in lithium niobate crystals

    International Nuclear Information System (INIS)

    Lamela, J.; Jaque, D.; Rodenas, A.; Jaque, F.; Torchia, G.A.; Vazquez, J.R.; Mendez, C.; Roso, L.

    2008-01-01

    Near-field-optical-microscopy has been used to study the micro-modifications caused by femtosecond laser pulses focused at the surface and in the volume of lithium niobate crystals. We have found experimental evidence of the existence, close to femtosecond ablation craters, of periodic modifications in the surface reflectivity. In addition, the potential application of near-field-optical microscopy for the spatial location of permanent modifications caused by femtosecond pulses focused inside lithium niobate crystals has been also demonstrated. (orig.)

  18. Conceptual design study of the hylife lithium waterfall laser fusion chamber. FY 1978 annual report to Lawrence Livermore Laboratory

    International Nuclear Information System (INIS)

    1978-01-01

    Conceptual design studies of the target chamber defined the general configuration and dimensions of the chamber and the inlet plenum, orifice plate, and nozzle plate concepts required to generate the desired lithium jet fall. Preliminary studies were performed of the target chamber interfaces with the liquid lithium supply system, the laser system, the pellet injection system, and the target chamber mounting and support system. Target chamber environmental effects resulting from typical thermonuclear burns were evaluated. The outlet region of the target chamber was outlined conceptually, and preliminary design considerations were given to the annular graphite reflector regions of the target chamber and the associated liquid lithium coolant passages

  19. Even-parity resonances with synchrotron radiation from Laser Excited Lithium at 1s^22p State

    Science.gov (United States)

    Huang, Ming-Tie; Wehlitz, Ralf

    2010-03-01

    Correlated many-body dynamics is still one of the unsolved fundamental problems in physics. Such correlation effects can be most clearly studied in processes involving single atoms for their simplicity.Lithium, being the simplest open shell atom, has been under a lot of study. Most of the studies focused on ground state lithium. However, only odd parity resonances can be populated through single photon (synchrotron radiation) absorption from ground state lithium (1s^22s). Lithium atoms, after being laser excited to the 1s^22p state, allow the study of even parity resonances. We have measured some of the even parity resonances of lithium for resonant energies below 64 eV. A single-mode diode laser is used to excite lithium from 1s^22s ground state to 1s^22p (^2P3/2) state. Photoions resulting from the interaction between the excited lithium and synchrotron radiation were analyzed and collected by an ion time-of-flight (TOF) spectrometer with a Z- stack channel plate detector. The Li^+ ion yield was recorded while scanning the undulator along with the monochromator. The energy scans have been analyzed regarding resonance energies and parameters of the Fano profiles. Our results for the observed resonances will be presented.

  20. Relationship between 578-nm (copper vapor) laser beam geometry and heat distribution within biological tissues

    Science.gov (United States)

    Ilyasov, Ildar K.; Prikhodko, Constantin V.; Nevorotin, Alexey J.

    1995-01-01

    Monte Carlo (MC) simulation model and the thermoindicative tissue phantom were applied for evaluation of a depth of tissue necrosis (DTN) as a result of quasi-cw copper vapor laser (578 nm) irradiation. It has been shown that incident light focusing angle is essential for DTN. In particular, there was a significant rise in DTN parallel to elevation of this angle up to +20 degree(s)C and +5 degree(s)C for both the MC simulation and tissue phantom models, respectively, with no further increase in the necrosis depth above these angles. It is to be noted that the relationship between focusing angles and DTN values was apparently stronger for the real target compared to the MC-derived hypothetical one. To what extent these date are applicable for medical practice can be evaluated in animal models which would simulate laser-assisted therapy for PWS or related dermatologic lesions with converged 578 nm laser beams.

  1. Lithium niobate bulk crystallization promoted by CO2 laser radiation

    Science.gov (United States)

    Ferreira, N. M.; Costa, F. M.; Nogueira, R. N.; Graça, M. P. F.

    2012-09-01

    The crystallization induced by laser radiation is a very promising technique to promote glass/ceramic transformation, being already used to produce crystalline patterns on glass surfaces. In this work, a SiO2-Li2O-Nb2O5 glass, prepared by the sol-gel route, was submitted to CO2 laser radiation and conventional heat-treatments in order to induce the LiNbO3 crystallization. The structure and morphology of the samples prepared by both routes was analyzed as a function of exposure time, radiation power and heat-treatment temperatures by XRD, Raman spectroscopy and SEM. The results reveal a correlation between the crystallization degree of LiNbO3 particles and glass matrix with the heat treatment type and experimental parameters. An heat-treatment at 650 °C/4 h was necessary to induce crystallization in heat treatments samples while 4 W/500 s was enough for laser radiation ones, corresponding a reduction time processing of ˜14 000 s.

  2. Differential absorption lidar measurements of atmospheric water vapor using a pseudonoise code modulated AlGaAs laser. Thesis

    Science.gov (United States)

    Rall, Jonathan A. R.

    1994-01-01

    Lidar measurements using pseudonoise code modulated AlGaAs lasers are reported. Horizontal path lidar measurements were made at night to terrestrial targets at ranges of 5 and 13 km with 35 mW of average power and integration times of one second. Cloud and aerosol lidar measurements were made to thin cirrus clouds at 13 km altitude with Rayleigh (molecular) backscatter evident up to 9 km. Average transmitter power was 35 mW and measurement integration time was 20 minutes. An AlGaAs laser was used to characterize spectral properties of water vapor absorption lines at 811.617, 816.024, and 815.769 nm in a multipass absorption cell using derivative spectroscopy techniques. Frequency locking of an AlGaAs laser to a water vapor absorption line was achieved with a laser center frequency stability measured to better than one-fifth of the water vapor Doppler linewidth over several minutes. Differential absorption lidar measurements of atmospheric water vapor were made in both integrated path and range-resolved modes using an externally modulated AlGaAs laser. Mean water vapor number density was estimated from both integrated path and range-resolved DIAL measurements and agreed with measured humidity values to within 6.5 percent and 20 percent, respectively. Error sources were identified and their effects on estimates of water vapor number density calculated.

  3. Retrieval of water vapor mixing ratios from a laser-based sensor

    Science.gov (United States)

    Tucker, George F.

    1995-01-01

    Langley Research Center has developed a novel external path sensor which monitors water vapor along an optical path between an airplane window and reflective material on the plane's engine. An infrared tunable diode laser is wavelength modulated across a water vapor absorption line at a frequency f. The 2f and DC signals are measured by a detector mounted adjacent to the laser. The 2f/DC ratio depends on the amount of wavelength modulation, the water vapor absorption line being observed, and the temperature, pressure, and water vapor content of the atmosphere. The present work concerns efforts to quantify the contributions of these factors and to derive a method for extracting the water vapor mixing ratio from the measurements. A 3 m cell was fabricated in order to perform laboratory tests of the sensor. Measurements of 2f/DC were made for a series of pressures and modulation amplitudes. During my 1994 faculty fellowship, a computer program was created which allowed 2f/DC to be calculated for any combination of the variables which effect it. This code was used to generate 2f/DC values for the conditions measured in the laboratory. The experimental and theoretical values agreed to within a few percent. As a result, the laser modulation amplitude can now be set in the field by comparing the response of the instrument to the calculated response as a function of modulation amplitude. Once the validity of the computer code was established, it was used to investigate possible candidate absorption lines. 2f/DC values were calculated for pressures, temperatures, and water vapor mixing ratios expected to be encountered in future missions. The results have been incorporated into a database which will be used to select the best line for a particular mission. The database will also be used to select a retrieval technique. For examples under some circumstances there is little temperature dependence in 2f/DC so temperature can be neglected. In other cases, there is a dependence

  4. Physics of zinc vaporization and plasma absorption during CO2 laser welding

    International Nuclear Information System (INIS)

    Dasgupta, A. K.; Mazumder, J.; Li, P.

    2007-01-01

    A number of mathematical models have been developed earlier for single-material laser welding processes considering one-, two-, and three-dimensional heat and mass transfers. However, modeling of laser welding of materials with multiple compositions has been a difficult problem. This paper addresses a specific case of this problem where CO 2 laser welding of zinc-coated steel, commonly used in automobile body manufacturing, is mathematically modeled. The physics of a low boiling point material, zinc, is combined with a single-material (steel) welding model, considering multiple physical phenomena such as keyhole formation, capillary and thermocapillary forces, recoil and vapor pressures, etc. The physics of laser beam-plasma interaction is modeled to understand the effect on the quality of laser processing. Also, an adaptive meshing scheme is incorporated in the model for improving the overall computational efficiency. The model, whose results are found to be in close agreement with the experimental observations, can be easily extended for studying zinc-coated steel welding using other high power, continuous wave lasers such as Nd:YAG and Yb:YAG

  5. Rapid growth of diamond-like-carbon films by copper vapor laser ablation

    International Nuclear Information System (INIS)

    McLean, W.; Warner, B.E.; Havstad, M.A.

    1995-04-01

    Visible light from a copper vapor laser (CVL) operating with 510 and 578 nm radiation (intensity ratio approximately 2:1), an average power of 100 W, a pulse duration of 50 ns, and a repetition frequency of 4.4 kHz has been shown to produce high quality diamond-like-carbon (DLC) films at fluences between 2x10 8 and 5x10 10 W/cm 2 . Maximum deposition rates of 2000 μm·cm 2 /h were obtained at 5x10 8 W/cm 2 . DLC films with hardness values of approximately 60 GPa were characterized by a variety of techniques to confirm DLC character, hydrogen content, and surface morphology. The presence of C 2 in the vapor plume was confirmed by the presence of the C 2 Swan bands in emission spectra obtained during the process. Economic implications of process scale-up to industrially meaningful component sizes are presented

  6. Influence of the helium-pressure on diode-pumped alkali-vapor laser

    Science.gov (United States)

    Gao, Fei; Chen, Fei; Xie, Ji-jiang; Zhang, Lai-ming; Li, Dian-jun; Yang, Gui-long; Guo, Jing

    2013-05-01

    Diode-pumped alkali-vapor laser (DPAL) is a kind of laser attracted much attention for its merits, such as high quantum efficiency, excellent beam quality, favorable thermal management, and potential scalability to high power and so on. Based on the rate-equation theory of end-pumped DPAL, the performances of DPAL using Cs-vapor collisionally broadened by helium are simulated and studied. With the increase of helium pressure, the numerical results show that: 1) the absorption line-width increases and the stimulated absorption cross-section decreases contrarily; 2) the threshold pumping power decreases to minimum and then rolls over to increase linearly; 3) the absorption efficiency rises to maximum initially due to enough large stimulated absorption cross-section in the far wings of collisionally broadened D2 transition (absorption transition), and then begins to reduce; 4) an optimal value of helium pressure exists to obtain the highest output power, leading to an optimal optical-optical efficiency. Furthermore, to generate the self-oscillation of laser, a critical value of helium pressure occurs when small-signal gain equals to the threshold gain.

  7. Properties of welded joints in laser welding of aeronautic aluminum-lithium alloys

    Science.gov (United States)

    Malikov, A. G.; Orishich, A. M.

    2017-01-01

    The work presents the experimental investigation of the laser welding of the aluminum-lithium alloys (system Al-Mg-Li) and aluminum alloy (system Al-Cu-Li) doped with Sc. The influence of the nano-structuring of the surface layer welded joint by the cold plastic deformation method on the strength properties of the welded joint is determined. It is founded that, regarding the deformation degree over the thickness, the varying value of the welded joint strength is different for these aluminum alloys.

  8. Desorption/ablation of lithium fluoride induced by extreme ultraviolet laser radiation

    Czech Academy of Sciences Publication Activity Database

    Blejchař, T.; Nevrlý, V.; Vašinek, M.; Dostál, M.; Kozubková, M.; Dlabka, J.; Stachoň, M.; Juha, Libor; Bitala, P.; Zelinger, Zdeněk; Pira, Peter; Wild, J.

    2016-01-01

    Roč. 61, č. 2 (2016), s. 131-138 ISSN 0029-5922. [PLASMA 2015 : International Conference on Research and Applications of Plasmas. Warsaw, 07.09.2015-11.09.2015] R&D Projects: GA ČR(CZ) GAP108/11/1312 Institutional support: RVO:68378271 ; RVO:61388955 Keywords : desorption * fluid dynamics * lithium fluoride * numerical simulation * plume expansion * pulsed laser ablation Subject RIV: BL - Plasma and Gas Discharge Physics; CF - Physical ; Theoretical Chemistry (UFCH-W) Impact factor: 0.760, year: 2016

  9. High quality long-wavelength lasers grown by atmospheric organometallic vapor phase epitaxy using tertiarybutylarsine

    International Nuclear Information System (INIS)

    Miller, B.I.; Young, M.G.; Oron, M.; Koren, U.; Kisker, D.

    1990-01-01

    High quality long-wavelength InGaAsP/InP lasers were grown by atmospheric organometallic vapor phase epitaxy using tertiarybutylarsine (TBA) as a substitute for AsH 3 . Electrical and photoluminescence measurements on InGaAs and InGaAsP showed that TBA-grown material was at least as good as AsH 3 material in terms of suitability for lasers. From two wafers grown by TBA, current thresholds I th as low as 11 mA were obtained for a 2-μm-wide semi-insulating blocking planar buried heterostructure laser lasing near 1.3 μm wavelength. The differential quantum efficiencies η D were as high as 21%/facet with a low internal loss α=21 cm -1 . In addition I th as low as 18 mA and η D as high as 18% have been obtained for multiplequantum well lasers at 1.54 μm wavelength. These results show that TBA might be used to replace AsH 3 without compromising on laser performance

  10. Pyroelectric field assisted ion migration induced by ultraviolet laser irradiation and its impact on ferroelectric domain inversion in lithium niobate crystals

    International Nuclear Information System (INIS)

    Ying, C. Y. J.; Mailis, S.; Daniell, G. J.; Steigerwald, H.; Soergel, E.

    2013-01-01

    The impact of UV laser irradiation on the distribution of lithium ions in ferroelectric lithium niobate single crystals has been numerically modelled. Strongly absorbed UV radiation at wavelengths of 244–305 nm produces steep temperature gradients which cause lithium ions to migrate and result in a local variation of the lithium concentration. In addition to the diffusion, here the pyroelectric effect is also taken into account which predicts a complex distribution of lithium concentration along the c-axis of the crystal: two separated lithium deficient regions on the surface and in depth. The modelling on the local lithium concentration and the subsequent variation of the coercive field are used to explain experimental results on the domain inversion of such UV treated lithium niobate crystals

  11. LASER RADIATION CHARACTERISTICS (BRIEF COMMUNICATIONS): Conversion of KrCl and XeCl laser radiation to the visible spectral range by stimulated Raman scattering in lead vapor

    Science.gov (United States)

    Evtushenko, Gennadii S.; Mel'chenko, S. V.; Panchenko, Aleksei N.; Tarasenko, Viktor F.

    1990-04-01

    Conversion of KrCl and XeCl laser radiation by stimulated Raman scattering was achieved in lead vapor. The KrCl laser radiation was converted into three lines in the visible region at λ = 406, 590, and 723 nm by transitions from both the ground and first excited levels of the lead atom. The conversion efficiency of XeCl laser radiation of low spatial coherence was found to be limited by the activation of a competing nonlinear process.

  12. Expansion dynamics and equilibrium conditions in a laser ablation plume of lithium: Modeling and experiment

    International Nuclear Information System (INIS)

    Stapleton, M.W.; McKiernan, A.P.; Mosnier, J.-P.

    2005-01-01

    The gas dynamics and atomic kinetics of a laser ablation plume of lithium, expanding adiabatically in vacuum, are included in a numerical model, using isothermal and isentropic self-similar analytical solutions and steady-state collisional radiative equations, respectively. Measurements of plume expansion dynamics using ultrafast imaging for various laser wavelengths (266-1064 nm), fluences (2-6.5 J cm -2 ), and spot sizes (50-1000 μm) are performed to provide input parameters for the model and, thereby, study the influence of laser spot size, wavelength, and fluence, respectively, on both the plume expansion dynamics and atomic kinetics. Target recoil pressure, which clearly affects plume dynamics, is included in the model. The effects of laser wavelength and spot size on plume dynamics are discussed in terms of plasma absorption of laser light. A transition from isothermal to isentropic behavior for spot sizes greater than 50 μm is clearly evidenced. Equilibrium conditions are found to exist only up to 300 ns after the plume creation, while complete local thermodynamic equilibrium is found to be confined to the very early parts of the expansion

  13. Cu2Sb thin film electrodes prepared by pulsed laser deposition f or lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Song, Seung-Wan; Reade, Ronald P.; Cairns, Elton J.; Vaughey, Jack T.; Thackeray, Michael M.; Striebel, Kathryn A.

    2003-08-01

    Thin films of Cu2Sb, prepared on stainless steel and copper substrates with a pulsed laser deposition technique at room temperature, have been evaluated as electrodes in lithium cells. The electrodes operate by a lithium insertion/copper extrusion reaction mechanism, the reversibility of which is superior when copper substrates are used, particularly when electrochemical cycling is restricted to the voltage range 0.65-1.4 V vs. Li/Li+. The superior performance of Cu2Sb films on copper is attributed to the more active participation of the extruded copper in the functioning of the electrode. The continual and extensive extrusion of copper on cycling the cells leads to the isolation of Li3Sb particles and a consequent formation of Sb. Improved cycling stability of both types of electrodes was obtained when cells were cycled between 0.65 and 1.4 V. A low-capacity lithium-ion cell with Cu2Sb and LiNi0.8Co0.15Al0.05O2 electrodes, laminated from powders, shows excellent cycling stability over the voltage range 3.15 - 2.2 V, the potential difference corresponding to approximately 0.65-1.4 V for the Cu2Sb electrode vs. Li/Li+. Chemical self-discharge of lithiated Cu2Sb electrodes by reaction with the electrolyte was severe when cells were allowed to relax on open circuit after reaching a lower voltage limit of 0.1 V. The solid electrolyte interphase (SEI) layer formed on Cu2Sb electrodes after cells had been cycled between 1.4 and 0.65 V vs. Li/Li+ was characterized by Fourier-transform infrared spectroscopy; the SEI layer contributes to the large irreversible capacity loss on the initial cycle of these cells. The data contribute to a better understanding of the electrochemical behavior of intermetallic electrodes in rechargeable lithium batteries.

  14. Highly sensitive analysis of boron and lithium in aqueous solution using dual-pulse laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Lee, Dong-Hyoung; Han, Sol-Chan; Kim, Tae-Hyeong; Yun, Jong-Il

    2011-12-15

    We have applied a dual-pulse laser-induced breakdown spectroscopy (DP-LIBS) to sensitively detect concentrations of boron and lithium in aqueous solution. Sequential laser pulses from two separate Q-switched Nd:YAG lasers at 532 nm wavelength have been employed to generate laser-induced plasma on a water jet. For achieving sensitive elemental detection, the optimal timing between two laser pulses was investigated. The optimum time delay between two laser pulses for the B atomic emission lines was found to be less than 3 μs and approximately 10 μs for the Li atomic emission line. Under these optimized conditions, the detection limit was attained in the range of 0.8 ppm for boron and 0.8 ppb for lithium. In particular, the sensitivity for detecting boron by excitation of laminar liquid jet was found to be excellent by nearly 2 orders of magnitude compared with 80 ppm reported in the literature. These sensitivities of laser-induced breakdown spectroscopy are very practical for the online elemental analysis of boric acid and lithium hydroxide serving as neutron absorber and pH controller in the primary coolant water of pressurized water reactors, respectively.

  15. Application of atomic vapor laser isotope separation to the enrichment of mercury

    International Nuclear Information System (INIS)

    Crane, J.K.; Erbert, G.V.; Paisner, J.A.; Chen, H.L.; Chiba, Z.; Beeler, R.G.; Combs, R.; Mostek, S.D.

    1986-09-01

    Workers at GTE/Sylvania have shown that the efficiency of fluorescent lighting may be markedly improved using mercury that has been enriched in the 196 Hg isotope. A 5% improvement in the efficiency of fluorescent lighting in the United States could provide a savings of ∼ 1 billion dollars in the corresponding reduction of electrical power consumption. We will discuss the results of recent work done at our laboratory to develop a process for enriching mercury. The discussion will center around the results of spectroscopic measurements of excited state lifetimes, photoionization cross sections and isotope shifts. In addition, we will discuss the mercury separator and supporting laser mesurements of the flow properties of mercury vapor. We will describe the laser system which will provide the photoionization and finally discuss the economic details of producing enriched mercury at a cost that would be attractive to the lighting industry

  16. Dual-comb spectroscopy of water vapor with a free-running semiconductor disk laser.

    Science.gov (United States)

    Link, S M; Maas, D J H C; Waldburger, D; Keller, U

    2017-06-16

    Dual-comb spectroscopy offers the potential for high accuracy combined with fast data acquisition. Applications are often limited, however, by the complexity of optical comb systems. Here we present dual-comb spectroscopy of water vapor using a substantially simplified single-laser system. Very good spectroscopy measurements with fast sampling rates are achieved with a free-running dual-comb mode-locked semiconductor disk laser. The absolute stability of the optical comb modes is characterized both for free-running operation and with simple microwave stabilization. This approach drastically reduces the complexity for dual-comb spectroscopy. Band-gap engineering to tune the center wavelength from the ultraviolet to the mid-infrared could optimize frequency combs for specific gas targets, further enabling dual-comb spectroscopy for a wider range of industrial applications. Copyright © 2017, American Association for the Advancement of Science.

  17. KTP laser selective vaporization of the prostate in the management of urinary retention due to BPH

    Science.gov (United States)

    Kleeman, M. W.; Nseyo, Unyime O.

    2003-06-01

    High-powered photoselective vaporization of the prostate (PVP) is a relatively new addition in the armamentarium against bladder outlet obstruction due to BPH. With BPH, the prostate undergoes stromal and epithelial hyperplasia, particularly in the transitional zone, mediated by dihydrotestosterone (DHT). This periurethral enlargement can compress the prostatic urethra leading to bladder outlet obstruction and eventually urinary retention. Treatment of uncomplicated symptomatic BPH has evolved from the standard transurethral resection of the prostate (TURP) to multiple medical therapies and the putative minimally invasive surgical procedures. These include microwave ablation, needle ablation, balloon dilation, stents, as well as fluid based thermo-therapy, ultrasound therapy and cryotherapy. Different forms of lasers have been applied to treat BPH with variable short and long term benefits of urinary symptoms. However, the controversy remains about each laser regarding its technical applicability and efficacy.

  18. Real-time qualitative study of forsterite crystal - Melt lithium distribution by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Lebedev, V. F.; Makarchuk, P. S.; Stepanov, D. N.

    2017-11-01

    A factor of lithium distribution between single-crystal forsterite (Cr,Li:Mg2SiO4) and its melt are studied by laser-induced breakdown spectroscopy. Lithium content in the crystalline phase is found to achieve a saturation at relatively low Li concentration in the melt (about 0.02%wt.). An algorithm and software are developed for real-time analysis of the studied spectra of lithium trace amounts at wide variation of the plasma radiation intensity. The analyzed plasma spectra processing method is based on the calculation of lithium emission part in the total emission of the target plasma for each recorded spectrum followed by the error estimation for the series of measurements in the normal distribution approximation.

  19. Ultrashort pulsed laser ablation for decollation of solid state lithium-ion batteries

    Science.gov (United States)

    Hördemann, C.; Anand, H.; Gillner, A.

    2017-08-01

    Rechargeable lithium-ion batteries with liquid electrolytes are the main energy source for many electronic devices that we use in our everyday lives. However, one of the main drawbacks of this energy storage technology is the use of liquid electrolyte, which can be hazardous to the user as well as the environment. Moreover, lithium-ion batteries are limited in voltage, energy density and operating temperature range. One of the most novel and promising battery technologies available to overcome the above-mentioned drawbacks is the Solid-State Lithium-Ion Battery (SSLB). This battery type can be produced without limitations to the geometry and is also bendable, which is not possible with conventional batteries1 . Additionally, SSLBs are characterized by high volumetric and gravimetric energy density and are intrinsically safe since no liquid electrolyte is used2-4. Nevertheless, the manufacturing costs of these batteries are still high. The existing production-technologies are comparable to the processes used in the semiconductor industry and single cells are produced in batches with masked-deposition at low deposition rates. In order to decrease manufacturing costs and to move towards continuous production, Roll2Roll production methods are being proposed5, 6. These methods offer the possibility of producing large quantities of substrates with deposited SSLB-layers. From this coated substrate, single cells can be cut out. For the flexible decollation of SSLB-cells from the substrate, new manufacturing technologies have to be developed since blade-cutting, punching or conventional laser-cutting processes lead to short circuiting between the layers. Here, ultra-short pulsed laser ablation and cutting allows the flexible decollation of SSLBs. Through selective ablation of individual layers, an area for the cutting kerf is prepared to ensure a shortcut-free decollation.

  20. High-temperature quadrupole mass spectrometer for studying vaporization from materials heated by a CO2 laser

    International Nuclear Information System (INIS)

    Fredin, L.; Hansen, G.P.; Sampson, M.P.; Margrave, J.L.; Behrens, R.G.

    1986-09-01

    To evaluate the effectiveness of mass spectrometry techniques in studying vaporization from selected materials, we designed a mass spectrometer than can be used either with a continuous wave or pulsed laser heating system or with a conventional furnace heating system. Our experimental apparatus, the components of which are described in detail, consisted of a quadrupole mass spectrometer positioned in a crossed-beam configuration, controlling electronics, a data acquisition system, a vacuum system, a cryogenic collimation system, and a laser heating system. Results of mass spectral scans taken during laser pyrolysis of polymeric materials and laser vaporization of graphite were compatible with data reported in other studies. Results of mass spectral studies of laser-induced combustion in the Ti + C system are also presented

  1. Loss of power output and laser fibre degradation during 120 watt lithium-triborate HPS laser vaporisation of the prostate

    Science.gov (United States)

    Hermanns, Thomas; Sulser, Tullio; Hefermehl, Lukas J.; Strebel, Daniel; Michel, Maurice-Stephan; Müntener, Michael; Meier, Alexander H.; Seifert, Hans-Helge

    2009-02-01

    It has recently been shown that laser fibre deterioration leads to a significant decrease of power output during 80 W potassium titanyl phosphate (KTP) laser vaporisation (LV) of the prostate. This decrease results in inefficient vaporisation especially towards the end of the procedure. For the new 120 W lithium-triborate (LBO) High Performance System (HPS) laser not only higher power but also changes in beam characteristics and improved fibre quality have been advertised. However, high laser power has been identified as a risk factor for laser fibre degradation. Between July and September 2008 25 laser fibres were investigated during routine 120 W LBO-LV in 20 consecutive patients. Laser beam power was measured at baseline and after the application of every 25 kJ during the LV procedure. Postoperatively, the surgeon subjectively rated the performance of the respective fibre on a scale from 1 to 4 (1 indicating perfect and 4 insufficient performance). Additionally, microscopic examination of the fibre tip was performed. Median energy applied was 212 kJ. Changes of power output were similar for all fibres. Typically, a steep decrease of power output within the first 50 kJ was followed by a continuous mild decrease until the end of the procedure. After the application of 50 kJ the median power output was 63% (58-73% interquartile range) of the baseline value. The median power output at the end of the 275 kJ-lifespan of the fibres was 42% (40-47%). The median surgeons' rating of the overall performance of the laser fibres was 2 and the median estimated final decrease of power output 60%. Some degree of degradation at the emission window was microscopically detectable in all cases after the procedure. However, even after the application of 275 kJ, these structural changes were only moderate. Minor degradation of the laser fibre was associated with a significant decrease of power output during 120 W LBO-LV. However, following an early, steep decrease, power output

  2. Evidence for the direct ejection of clusters from non-metallic solids during laser vaporization

    International Nuclear Information System (INIS)

    Bloomfield, L.A.; Yang, Y.A.; Xia, P.; Junkin, A.L.

    1991-01-01

    This paper reports on the formation of molecular scale particles or clusters of alkali halides and semiconductors during laser vaporization of solids. By measuring the abundances of cluster ions produced in several different source configurations, the authors have determined that clusters are ejected directly from the source sample and do not need to grow from atomic or molecular vapor. Using samples of mixed alkali halide powders, the authors have found that unalloyed clusters are easily produced in a source that prevents growth from occurring after the clusters leave the sample surface. However, melting the sample or encouraging growth after vaporization lead to the production of alloyed cluster species. The sizes of the ejected clusters are initially random, but the population spectrum quickly becomes structured as hot, unstable-sized clusters decay into smaller particles. In carbon, large clusters with odd number of atoms decay almost immediately. The hot even clusters also decay, but much more slowly. The longest lived clusters are the magic C 50 and C 60 fullerenes. The mass spectrum of large carbon clusters evolves in time from structureless, to only the even clusters, to primarily C 50 and C 60 . If cluster growth is encouraged, the odd clusters reappear and the population spectrum again becomes relatively structureless

  3. Near-infrared diode laser absorption diagnostic for temperature and water vapor in a scramjet combustor

    International Nuclear Information System (INIS)

    Liu, Jonathan T.C.; Rieker, Gregory B.; Jeffries, Jay B.; Gruber, Mark R.; Carter, Campbell D.; Mathur, Tarun; Hanson, Ronald K.

    2005-01-01

    Tunable diode laser absorption measurements of gas temperature and water concentration were made at the exit of a model scramjet combustor fueled on JP-7. Multiplexed, fiber-coupled, near-infrared distributed feedback lasers were used to probe three water vapor absorption features in the 1.34-1.47 μm spectral region (2v1and v1+ v3overtone bands). Ratio thermometry was performed using direct-absorption wavelength scans of isolated features at a 4-kHz repetition rate, as well as 2f wavelength modulation scans at a 2-kHz scan rate. Large signal-to-noise ratios demonstrate the ability of the optimally engineered optical hardware to reject beam steering and vibration noise. Successful measurements were made at full combustion conditions for a variety of fuel/air equivalence ratios and at eight vertical positions in the duct to investigate spatial uniformity. The use of three water vapor absorption features allowed for preliminary estimates of temperature distributions along the line of sight. The improved signal quality afforded by 2f measurements, in the case of weak absorption, demonstrates the utility of a scanned wavelength modulation strategy in such situations

  4. Theoretical investigation on exciplex pumped alkali vapor lasers with sonic-level gas flow

    Science.gov (United States)

    Xu, Xingqi; Shen, Binglin; Huang, Jinghua; Xia, Chunsheng; Pan, Bailiang

    2017-07-01

    Considering the effects of higher excited and ion energy states and utilizing the methodology in the fluid mechanics, a modified model of exciplex pumped alkali vapor lasers with sonic-level flowing gas is established. A comparison of output characters between subsonic flow and supersonic flow is made. In this model, higher excited and ion energy states are included as well, which modifies the analysis of the kinetic process and introduces larger heat loading in an operating CW exciplex-pumped alkali vapor laser. The results of our calculations predict that subsonic flow has an advantage over supersonic flow under the same fluid parameters, and stimulated emission in the supersonic flow would be quenched while the pump power reaching a threshold value of the fluid choking effect. However, by eliminating the influence of fluid characters, better thermal management and higher optical conversion efficiency can be obtained in supersonic flow. In addition, we make use of the "nozzle-diffuser" to build up the closed-circle flowing experimental device and gather some useful simulated results.

  5. Fabrication and characterization of a cell electrostimulator device combining physical vapor deposition and laser ablation

    Science.gov (United States)

    Aragón, Angel L.; Pérez, Eliseo; Pazos, Antonio; Bao-Varela, Carmen; Nieto, Daniel

    2017-08-01

    In this work we present the process of fabrication and optimization of a prototype of a cell electrostimulator device for medical application combining physical vapor deposition and laser ablation. The fabrication of the first prototype begins with a deposition of a thin layer of 200 nm of aluminium on a borosilicate glass substrate using physical vapor deposition (PVD). In the second stage the geometry design of the electrostimulator is made in a CAD-like software available in a Nd:YVO4 Rofin Power line 20E, operating at the fundamental wavelength of 1064 nm and 20 ns pulse width. Choosing the proper laser parameters the negative of the electrostimulator desing is ablated. After that the glass is assembled between two polycarbonate sheets and a thick sheet of polydimethylsiloxane (PDMS). The PDMS sheet has a round hole in where cells are placed. There is also included a thin soda-lime silicate glass (100 μm) between the electrostimulator and the PMDS to prevent the cells for being in contact with the electric circuit. In order to control the electrical signal applied to the electrostimulator is used a digital I/O device from National Instruments (USB-6501) which provides 5 V at the output monitored by a software programmed in LabVIEW. Finally, the optical and electrical characterization of the cell electrostimulator device is presented.

  6. Comparative studies of laser annealing technique and furnace annealing by X-ray diffraction and Raman analysis of lithium manganese oxide thin films for lithium-ion batteries

    International Nuclear Information System (INIS)

    Pröll, J.; Weidler, P.G.; Kohler, R.; Mangang, A.; Heißler, S.; Seifert, H.J.; Pfleging, W.

    2013-01-01

    The structure and phase formations of radio frequency magnetron sputtered lithium manganese oxide thin films (Li 1.1 Mn 1.9 O 4 ) under ambient air were studied. The influence of laser annealing and furnace annealing, respectively, on the bulk structure and surface phases was compared by using ex-situ X-ray diffraction and Raman analysis. Laser annealing technique formed a dominant (440)-reflection, furnace annealing led to both, (111)- and (440)-reflections within a cubic symmetry (S.G. Fd3m (227)). Additionally, in-situ Raman and in-situ X-ray diffraction were applied for online detection of phase transformation temperatures. In-situ X-ray diffraction measurements clearly identified the starting temperature for the (111)- and (440)-reflections around 525 °C and 400 °C, respectively. The 2θ Bragg peak positions of the characteristic (111)- and (440)-reflections were in good agreement with those obtained through conventional furnace annealing. Laser annealing of lithium manganese oxide films provided a quick and efficient technique and delivered a dominant (440)-reflection which showed the expected electrochemical behavior of the well-known two-step de-/intercalation process of lithium-ions into the cubic spinel structure within galvanostatic testing and cyclic voltammetry. - Highlights: ► Formation of cubic spinel-like phase of Li–Mn–O thin films by rapid laser annealing ► Laser annealing at 680 °C and 100 s was demonstrated as quick crystallization method. ► 400 °C was identified as characteristic onset temperature for (440)-reflex formation

  7. Laser absorption spectroscopy of water vapor confined in nanoporous alumina: wall collision line broadening and gas diffusion dynamics.

    Science.gov (United States)

    Svensson, Tomas; Lewander, Märta; Svanberg, Sune

    2010-08-02

    We demonstrate high-resolution tunable diode laser absorption spectroscopy (TDLAS) of water vapor confined in nanoporous alumina. Strong multiple light scattering results in long photon pathlengths (1 m through a 6 mm sample). We report on strong line broadening due to frequent wall collisions (gas-surface interactions). For the water vapor line at 935.685 nm, the HWHM of confined molecules are about 4.3 GHz as compared to 2.9 GHz for free molecules (atmospheric pressure). Gas diffusion is also investigated, and in contrast to molecular oxygen (that moves rapidly in and out of the alumina), the exchange of water vapor is found very slow.

  8. A Fundamental Study of Laser Beam Welding Aluminum-Lithium Alloy 2195 for Cryogenic Tank Applications

    Science.gov (United States)

    Martukanitz, R. P.; Jan. R.

    1996-01-01

    Based on the potential for decreasing costs of joining stiffeners to skin by laser beam welding, a fundamental research program was conducted to address the impediments identified during an initial study involving laser beam welding of aluminum-lithium alloys. Initial objectives of the program were the identification of governing mechanism responsible for process related porosity while establishing a multivariant relationship between process parameters and fusion zone geometry for laser beam welds of alloy 2195. A three-level fractional factorial experiment was conducted to establish quantitative relationships between primary laser beam processing parameters and critical weld attributes. Although process consistency appeared high for welds produced during partial completion of this study, numerous cracks on the top-surface of the welds were discovered during visual inspection and necessitated additional investigations concerning weld cracking. Two experiments were conducted to assess the effect of filler alloy additions on crack sensitivity: the first experiment was used to ascertain the effects of various filler alloys on cracking and the second experiment involved modification to process parameters for increasing filler metal dilution. Results indicated that filler alloys 4047 and 4145 showed promise for eliminating cracking.

  9. The accumulation of femtosecond laser radiation energy in crystals of lithium fluoride

    Science.gov (United States)

    Dresvyanskiy, V. P.; Glazunov, D. S.; Alekseev, S. V.; Losev, V. F.; Chadraa, B.; Bukhtsooj, O.; Baasankhuu, N.; Zandan, B.; Martynovich, E. F.

    2015-12-01

    We present the results of studies of energy accumulation during the non-destructive interaction of extremely intense near infrared laser radiation with model wide band gap dielectric crystals of lithium fluoride, when the intensity of pulses is sufficient for effective highly nonlinear absorption of light and for the excitation of the electron subsystem of matter and the energy of pulses is still not sufficient for significant heating, evaporation, laser breakdown or other destruction to occur. We studied the emission of energy in the form of light sum of thermally stimulated luminescence accumulated under conditions of self-focusing and multiple filamentation of femtosecond laser radiation. It was established that it's the F2 and F3+ color centers and supplementary to them centers of interstitial type which accumulate energy under the action of a single femtosecond laser pulses. When irradiated by series of pulses the F3, F3- and F4 centers additionally appear. F2 centers are the main centers of emission in the process of thermally stimulated luminescence of accumulated energy. The interstitial fluoride ions (I-centers) are the kinetic particles. They split off from the X3- centers in the result of thermal decomposition of latter on the I-centers and molecules X20. I-centers recombine with F3+ centers and form F2 centers in excited state. The latter produce the characteristic emission spectrum emitted in the form of thermally stimulated luminescence.

  10. Laser beam welding of high strength aluminium-lithium alloys; Laserstrahlschweissen von hochfesten Aluminium-Lithium Legierungen

    Energy Technology Data Exchange (ETDEWEB)

    Enz, Josephin

    2012-07-01

    The present development in aircraft industry determined by the demand for a higher cost-effectiveness. Laser beam welding is one of the most promising joining technologies for the application in the aircraft industry through the considerable reduction of the production costs. Furthermore the weight of an aircraft structure can be reduced by the use of light and high strength aluminium alloys. This paper deals with the development of a process for the laser beam welding of a skin-stringer-joint where the Al-Li-alloy AA2196 is used as stringer material and the Al-Li-alloy AA2198 is used as skin and stringer material. By the use of design of experiments the optimal welding process parameters for different material combinations were determined which will be used for the welding of a 5-stringer panel. Therefore the weld seams of the joints were tested for irregularities and microstructural characteristics. In addition several mechanical tests were performed, which define the quality of the welded joint. Furthermore the influence of the oxide layer and the welding preparation on the welding performance was investigated. (orig.) [German] Die derzeitigen Entwicklungen im Flugzeugbau werden durch die allgemeine Forderung nach einer Steigerung der Wirtschaftlichkeit bestimmt. Das Laserstrahlschweissen ist dabei eines der vielversprechendsten Fuegeverfahren fuer die Anwendung im Flugzeugbau durch das die Herstellungskosten deutlich reduziert werden koennen. Zudem kann durch die Verwendung von leichten und hochfesten Aluminium-Legierungen das Gewicht einer Flugzeugstruktur zusaetzlich reduziert werden. Die vorliegende Arbeit befasst sich mit der Entwicklung eines Prozesses zum Laserstrahlschweissen einer Skin-Stringer-Verbindung aus den Aluminium-Lithium-Legierungen AA2196 (als Stringer-Werkstoff) und AA2198 (als Skin- und Stringer-Werkstoff). Unter Verwendung der statistischen Versuchsplanung wurden die optimalen Einstellungen der Schweissprozessparameter fuer die

  11. Laser energy-pooling processes in an optically thick Cs vapor near a dissipative surface

    International Nuclear Information System (INIS)

    Gagne, Jean-Marie; Le Bris, Karine; Gagne, Marie-Claude

    2002-01-01

    We characterize, for the first time to our knowledge, the laser-induced backward fluorescence (retrofluorescence) spectra that result from energy-pooling collisions between Cs atoms near a dissipative thin Cs layer on a glass substrate. We resolve, experimentally and theoretically, the laser spectroscopic problem of energy-pooling processes related to the nature of the glass-metallic vapor interface. Our study focused on the integrated laser-induced retrofluorescence spectra for the 455.5-nm (7 2 P 3/2 -6 2 S 1/2 ) and 852.2-nm (6 2 P 3/2 -6 2 S 1/2 ) lines as a function of laser scanning through pumping resonance at the 852.2-nm line. We experimentally investigate the retrofluorescence from 420 to 930 nm, induced by a diode laser tuned either in the wings or in the center of the pumping resonance line. We present a detailed theoretical model of the retrofluorescence signal based on the radiative transfer equation, taking into account the evanescent wave of the excited atomic dipole strongly coupled with a dissipative surface. Based on theoretical and experimental results, we evaluate the effective nonradiative transfer rate A(bar sign) 6 2 P 3/2 →6 2 S 1/2s f for atoms in the excited 6 2 P 3/2 level located in the near-field region of the surface of the cell. Values extracted from the energy-pooling process analysis are equivalent to those found directly from the 852.2-nm resonance retrofluorescence line. We show that the effective energy-pooling coefficients k-tilde 7 2 P 3/2 and k-tilde 7 2 P 1/2 are approximately equal. The agreement between theory and experiment is remarkably good, considering the simplicity of the model

  12. Explosive vaporization induced by high-power CO2-laser target interactions

    International Nuclear Information System (INIS)

    Hugenschmidt, M.; Vollrath, K.

    1976-01-01

    The interactions of high-power laser pulses with targets such as metals or dielectric materials causes a series of optical, thermal, and mechanical processes. Thereby, heating, melting, and vaporization can take place in a short time. At power densities of about 10 7 to several 10 8 W/cm 2 this can even be produced explosively. As compared to continuous ablation, this type of interaction can remove greater masses from the bulk of material. The investigations are performed by using an electron-beam preionized CO 2 -laser acting on different target materials. The energy of the laser pulses is about 30 J, the pulse-half-widths of the long-tail pulses 4 to 6 μs. Optical measurements yield some information on threshold values for these processes, for the formation and expansion of plasmas, and for the ejection of material in form of greater particles. High speed photographic techniques include a rotating mirror- and an image converter camera. Starting from shock-wave theory, gas dynamic equations (in unidimensional approximation) allow for a quantitative determination of the specific internal energies and pressures in the case of optical detonation. (orig.) [de

  13. High-speed microjet generation using laser-induced vapor bubbles

    Science.gov (United States)

    Oudalov, Nikolai; Tagawa, Yoshiyuki; Peters, Ivo; Visser, Claas-Willem; van der Meer, Devaraj; Prosperetti, Andrea; Sun, Chao; Lohse, Detlef

    2011-11-01

    The generation and evolution of microjets are studied both experimentally and numerically. The jets are generated by focusing a laser pulse into a microscopic capillary tube (~50 μm) filled with water-based red dye. A vapor bubble is created instantly after shooting the laser (<1 μs), sending out a shockwave towards the curved free surface at which the high-speed microjet forms. The process of jet formation is captured using high-speed recordings at 1.0 × 106 fps. The velocity of the microjets can reach speeds of ~850 m/s while maintaining a very sharp geometry. The high-speed recordings enable us to study the effect of several parameters on the jet velocity, e.g. the absorbed energy and the distance between the laser spot and the free surface.The results show a clear dependence on these variables, even for supersonic speeds. Comparisons with numerical simulations confirm the nature of these dependencies.

  14. Development of long life pulse power supply for copper vapor laser. Do joki laser yo chojumyo reiki dengen no kaihatsu. ; Saidai shutsuryoku unten oyobi laser hasshin

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, T.; Goto, N.; Nemoto, K. (Central Research Inst. of Electric Power Industry, Tokyo (Japan))

    1990-04-01

    Long life pulse power supply for Cu vapor laser was developed. This is composed of the pulse generation circuit and the pulse compression circuit. Current pulse of 10 mu second pulse width is generated in the pulse generating circuit by switching electric charge on the condensor charged through GTO (gate turn off) thyristors. The pulse compression circuit makes the current pulse fast to 300ms utilizing the difference of inductance at the saturation and the unsaturation on the circuit which uses a reactor having saturable property using a ferromagnetic substance for the core as the magnetic switch. The operation was carried out at the GTO generasting full power. Co base amorphous alloy of low loss was used for the core of saturable inductor and the circuit efficiency of 77% could be obtained by suppressing the heat generation in core even at 4,000Hz operation. The full output power of 8.2kW was possible which corresponds to 100W class laser oscillation. Repeated Cu vapor laser oscillation of 30W succeeded at the condition of 4,000Hz and power supply output of 5.9kW. 7 refs., 21 figs., 8 tabs.

  15. Investigation of pump-to-seed beam matching on output features of Rb and Cs vapor laser amplifiers

    Science.gov (United States)

    Shen, Binglin; Huang, Jinghua; Xu, Xingqi; Xia, Chunsheng; Pan, Bailiang

    2018-05-01

    Taking into account the beam radii of pump light and seed laser along the entire length of the cell and their intensities in the cross section, a physical model with ordinary differential equation methods for alkali vapor amplifiers is established. Applied to the reported optically pumped Rb and diode-pumped Cs vapor amplifiers, the model shows good agreement between the calculated and measured dependence of amplified power on the seed power. A larger width of the spontaneous emission region as compared to the widths of pump absorption and laser emission regions, which will result in very high energy losses, is observed in the cell. Influence of pump and seed beam waists on output performance is calculated, showing that the pump and seed beam should match each other not only in shape but also in size, thus an optimal combination of beam radii is very important for efficient operation of alkali vapor amplifiers.

  16. Diode-laser-based water vapor differential absorption lidar (DIAL) profiler evaluation

    Science.gov (United States)

    Spuler, S.; Weckwerth, T.; Repasky, K. S.; Nehrir, A. R.; Carbone, R.

    2012-12-01

    We are in the process of evaluating the performance of an eye-safe, low-cost, diode-laser-based, water vapor differential absorption lidar (DIAL) profiler. This class of instrument may be capable of providing continuous water vapor and aerosol backscatter profiles at high vertical resolution in the atmospheric boundary layer (ABL) for periods of months to years. The technology potentially fills a national long term observing facility gap and could greatly benefit micro- and meso-meteorology, water cycle, carbon cycle and, more generally, biosphere-hydrosphere-atmosphere interaction research at both weather and climate variability time scales. For the evaluation, the Montana State University 3rd generation water vapor DIAL was modified to enable unattended operation for a period of several weeks. The performance of this V3.5 version DIAL was tested at MSU and NCAR in June and July of 2012. Further tests are currently in progress with Howard University at Beltsville, Maryland; and with the National Weather Service and Oklahoma University at Dallas/Fort Worth, Texas. The presentation will include a comparison of DIAL profiles against meteorological "truth" at the aforementioned locations including: radiosondes, Raman lidars, microwave and IR radiometers, AERONET and SUOMINET systems. Instrument reliability, uncertainty, systematic biases, detection height statistics, and environmental complications will be evaluated. Performance will be judged in the context of diverse scientific applications that range from operational weather prediction and seasonal climate variability, to more demanding climate system process studies at the land-canopy-ABL interface. Estimating the extent to which such research and operational applications can be satisfied with a low cost autonomous network of similar instruments is our principal objective.

  17. High temperature vapor pressures of stainless steel type 1.4970 and of some other pure metals from laser evaporation

    International Nuclear Information System (INIS)

    Bober, M.; Singer, J.

    1984-10-01

    For the safety analysis of nuclear reactors vapor pressure data of stainless steel are required up to temperatures exceeding 4000 K. In analogy to the classic boiling point method a new technique was developed to measure the high-temperature vapor pressures of stainless steel and other metals from laser vaporization. A fast pyrometer, an ion current probe and an image converter camera are used to detect incipient boiling from the time-temperature curve. The saturated-vapor pressure curves of stainless steel (Type 1.4970), being a cladding material of the SNR 300 breeder reactor, and of molybdenum are experimentally determined in the temperature ranges of 2800-3900 K and 4500-5200 K, respectively. The normal boiling points of iron, nickel, titanium, vanadium and zirconium are verified. Besides, spectral emissivity values of the liquid metals are measured at the pyrometer wavelengths of 752 nm and/or 940 nm. (orig.) [de

  18. Plasmakinetic enucleation of prostate versus 160-W laser photoselective vaporization for the treatment of benign prostatic hyperplasia

    Directory of Open Access Journals (Sweden)

    Si-Jun Wang

    2017-01-01

    Full Text Available To evaluate the safety and efficacy of plasmakinetic enucleation of the prostate (PKEP for the treatment of symptomatic benign prostatic hyperplasia (BPH compared with 160-W lithium triboride laser photoselective vaporization of the prostate (PVP. From February 2011 to July 2012, a prospective nonrandomized study was performed. One-hundred one patients underwent PKEP, and 110 underwent PVP. No severe intraoperative complications were recorded, and none of the patients in either group required a blood transfusion. Shorter catheterization time (38.14 ± 23.64 h vs 72.54 ± 28.38 h, P< 0.001 and hospitalization (2.32 ± 1.25 days vs 4.07 ± 1.23 days, P< 0.001 were recorded in the PVP group. At 12-month postoperatively, the PKEP group had a maintained and statistically improvement in International Prostate Symptom Score (IPSS (4.07 ± 2.07 vs 5.00 ± 2.10; P< 0.001, quality of life (QoL (1.08 ± 0.72 vs 1.35 ± 0.72; P= 0.007, maximal urinary flow rate (Qmax (24.75 ± 5.87 ml s−1 vs 22.03 ± 5.04 ml s−1 ; P< 0.001, postvoid residual urine volume (PVR (14.29 ± 6.97 ml vs 17.00 ± 6.11 ml; P= 0.001, and prostate-specific antigen (PSA value (0.78 ± 0.57 ng ml−1 vs 1.27 ± 1.07 ng ml−1 ; P< 0.001. Both PKEP and PVP relieve low urinary tract symptoms (LUTS due to BPH with low complication rates. PKEP can completely remove prostatic adenoma while the total amount of tissue removed by PVP is less than that can be removed by PKEP. Based on our study of the follow-up, PKEP provides better postoperative outcomes than PVP.

  19. Lithium tantalate single crystal for pyroelectricity-based laser energy-meter: growth, application and phase transition study

    International Nuclear Information System (INIS)

    Bhaumik, Indranil; Ganesamoorthy, S.; Bhatt, R.; Karnal, A.K.; Gupta, P.K.

    2009-01-01

    Single crystals of lithium tantalate have been grown. Dielectric-spectroscopy study reveals phase transition in congruent lithium tantalate (CLT) single crystal is diffusive and frequency dependent in contrast to that in near stoichiometric lithium tantalate where it is sharper. The ac conductivity measurements show that the conductivity is lower for 0.5Mg-SLT as compared to 1.0Mg-SLT. This is explained in terms of a Li-vacancy model. Calculation of activation energy from the lnσ vs. 1000/T plot reveals that hopping of Li + ions becomes difficult for 0.5 Mg-SLT. The pyroelectric response of CLT for pulsed Nd:YAG laser output has been tested. (author)

  20. Vertically aligned carbon nanotube growth by pulsed laser deposition and thermal chemical vapor deposition methods

    International Nuclear Information System (INIS)

    Sohn, Jung Inn; Nam, Chunghee; Lee, Seonghoon

    2002-01-01

    We have grown vertically aligned carbon nanotubes on the various substrates such as a planar p-type Si(1 0 0) wafer, porous Si wafer, SiO 2 , Si 3 N 4 , Al 2 O 3 , and Cr by thermal chemical vapor deposition (CVD) at 800 deg.C, using C 2 H 2 gas as a carbon source and Fe catalyst films deposited by a pulsed laser on the substrates. The Fe films were deposited for 5 min by pulsed laser deposition (PLD). The advantage of Fe deposition by PLD over other deposition methods lies in the superior adhesion of Fe to a Si substrate due to high kinetic energies of the generated Fe species. Scanning electron microscopy (SEM) images show that vertically well-aligned carbon nanotubes are grown on Fe nanoparticles formed from the thermal annealing of the Fe film deposited by PLD on the various substrates. Atomic force microscopy (AFM) images show that the Fe film annealed at 800 deg.C is broken to Fe nanoparticles of 10-50 nm in size. We show that the appropriate density of Fe nanoparticles formed from the thermal annealing of the film deposited by PLD is crucial in growing vertically aligned carbon nanotubes. Using a PLD and a lift-off method, we developed the selective growth of carbon nanotubes on a patterned Fe-coated Si substrate

  1. Differential mobility analysis of nanoparticles generated by laser vaporization and controlled condensation (LVCC)

    International Nuclear Information System (INIS)

    Abdelsayed, Victor; El-Shall, M. Samy; Seto, Takafumi

    2006-01-01

    Silicon and iron aluminide (FeAl) nanoparticles were synthesized by a laser vaporization controlled condensation (LVCC) method. The particles generated by the laser ablation of solid targets were transported and deposited in the presence of well-defined thermal and electric field in a newly designed flow-type LVCC chamber. The deposition process of nanoparticles was controlled by the balance of the external forces; i.e., gas flow, thermophoretic and electrostatic forces. The size distributions of generated nanoparticles were analyzed using a low-pressure differential mobility analyzer (LP-DMA). The effect of synthesis condition on the size distribution was analyzed by changing the pressure of the carrier gas (20-200 Torr), the temperature gradient in the LVCC chamber (ΔT=0-190 deg. C) and the electric field applied between the LVCC chamber plates (E=0-3000 V/m). It was found that electrostatic field was effective to selectively deposit small size nanoparticles (about 10 nm) with expelling large droplet-like particles

  2. The electrical characteristic and gain behavior as a function of the radial distance from the laser axis in a copper vapor laser

    International Nuclear Information System (INIS)

    Gal, G.

    1989-06-01

    The dependence of few parameters (related to the laser gain) on the radial distance from the laser axis, is observed very easily in a large-bore Copper Vapor Laser (CVL). An 80-mm-bore CVL which has reproducible parameters for research purposes has been constructed. The temporal development of the gain at different radial distances in this laser has been measured. A narrow probing beam from a small CVL operating as a oscillator has been used for the measurements, while the large-bore CVL has been operated as an amplifier and probed by this beam at different radial points. The electric response of the laser has also been checked and lead to the conclusion that raising the electrons energy in the laser plasma entails higher gain. As the laser tube wall was moved towards the laser axis, a temporal lag in the gain development and a reduction in its size has been found. The temporal lag is related to skin effect which delays the penetration of the electric field in the plasma towards the laser axis. The reduction in gain is related to the radial dependence of the population of the laser lower levels. It has also been found that under saturation the average power per unit area extracted from the laser is weakly dependent on the radial distance. (author)

  3. Inscription of type I and depressed cladding waveguides in lithium niobate using a femtosecond laser.

    Science.gov (United States)

    Bhardwaj, S; Mittholiya, K; Bhatnagar, A; Bernard, R; Dharmadhikari, J A; Mathur, D; Dharmadhikari, A K

    2017-07-10

    We describe two types of waveguides (type I and depressed cladding) inscribed in lithium niobate using a variable repetition rate (200 kHz-25 MHz), 270 fs duration fiber laser. The type I modification-based waveguides have propagation losses in the range from 1.2 to 10 dB/cm at 1550 nm, depending on experimental parameters. These waveguides are not permanent; they deteriorate over time. Such deterioration of waveguides can be slowed down from 30 days to 100 days by pre-annealing the samples and by writing at a 720 kHz laser repetition rate. The propagation losses measured at 1550 nm show significant improvement for pre-annealed samples. The depressed cladding-inscribed waveguides are permanent, but the propagation loss depends on the number of damage tracks. A track separation of ∼1  μm between adjacent damage tracks yields the lowest propagation loss of 0.5 dB/cm at 1550 nm for a 40 μm diameter waveguide. We observe multimode guidance for sizes in the range of 20-80 μm in these waveguide structures at 1550 nm. Their crystalline nature is found to remain intact, as inferred from second-harmonic generation within the waveguide region.

  4. Laser chemical vapor deposition of millimeter scale three-dimensional shapes

    Science.gov (United States)

    Shaarawi, Mohammed Saad

    2001-07-01

    Laser chemical vapor deposition (LCVD) has been successfully developed as a technique to synthesize millimeter-scale components directly from the gas phase. Material deposition occurs when heat generated by the interaction of a laser beam with a substrate thermally decomposes the gas precursor. Selective illumination or scanning the laser beam over portions of a substrate forms the single thin layer of material that is the building block of this process. Sequential scanning of the laser in a pre-defined pattern on the substrate and subsequent deposit causes the layers to accumulate forming the three-dimensional shape. The primary challenge encountered in LCVD shape forming is the synthesis of uniform layers. Three deposition techniques are studied to address this problem. The most successful technique, Active Surface Deposition, is based on the premise that the most uniform deposits are created by measuring the deposition surface topology and actively varying the deposition rate in response to features at the deposition surface. Defects observed in the other techniques were significantly reduced or completely eliminated using Active Surface Deposition. The second technique, Constant Temperature Deposition, maintains deposit uniformity through the use of closed-loop modulation of the laser power to sustain a constant surface temperature during deposition. The technique was successful in depositing high quality graphite tubes >2 mm tall from an acetylene precursor and partially successful in depositing SiC + C composite tubes from tetramethylsilane (TMS). The final technique, Constant Power Deposition, is based on the premise that maintaining a uniform power output throughout deposition would result in the formation of uniform layers. Constant Power Deposition failed to form coherent shapes. Additionally, LCVD is studied using a combination of analytic and numerical models to gain insight into the deposition process. Thermodynamic modeling is used to predict the

  5. Computer modeling of the sensitivity of a laser water vapor sensor to variations in temperature and air speed

    Science.gov (United States)

    Tucker, George F.

    1994-01-01

    Currently, there is disagreement among existing methods of determining atmospheric water vapor concentration at dew-points below -40 C. A major source of error is wall effects which result from the necessity of bringing samples into the instruments. All of these instruments also have response times on the order of seconds. NASA Langley is developing a water vapor sensor which utilizes the absorption of the infrared radiation produced by a diode laser to estimate water vapor concentration. The laser beam is directed through an aircraft window to a retroreflector located on an engine. The reflected beam is detected by an infrared detector located near the laser. To maximize signal to noise, derivative signals are analyzed. By measuring the 2f/DC signal and correcting for ambient temperature, atmospheric pressure and air speed (which results in a Doppler shifting of the laser beam), the water vapor concentration can be retrieved. Since this is an in situ measurement there are no wall effects and measurements can be made at a rate of more than 20 per second. This allows small spatial variations of water vapor to be studied. In order to study the sensitivity of the instrument to variations in temperature and air speed, a computer program which generated the 2f, 3f, 4f, DC and 2f/DC signals of the instrument as a function of temperature, pressure and air speed was written. This model was used to determine the effect of errors in measurement of the temperature and air speed on the measured water vapor concentration. Future studies will quantify the effect of pressure measurement errors, which are expected to be very small. As a result of these studied, a retrieval algorithm has been formulated, and will be applied to data taken during the PEM-West atmospheric science field mission. Spectroscopic studies of the water vapor line used by the instrument will be used to refine this algorithm. To prepare for these studies, several lasers have been studied to determine their

  6. Polarization switching detection method using a ferroelectric liquid crystal for dichroic atomic vapor laser lock frequency stabilization techniques.

    Science.gov (United States)

    Dudzik, Grzegorz; Rzepka, Janusz; Abramski, Krzysztof M

    2015-04-01

    We present a concept of the polarization switching detection method implemented for frequency-stabilized lasers, called the polarization switching dichroic atomic vapor laser lock (PSDAVLL) technique. It is a combination of the well-known dichroic atomic vapor laser lock method for laser frequency stabilization with a synchronous detection system based on the surface-stabilized ferroelectric liquid crystal (SSFLC).The SSFLC is a polarization switch and quarter wave-plate component. This technique provides a 9.6 dB better dynamic range ratio (DNR) than the well-known two-photodiode detection configuration known as the balanced polarimeter. This paper describes the proposed method used practically in the VCSEL laser frequency stabilization system. The applied PSDAVLL method has allowed us to obtain a frequency stability of 2.7×10⁻⁹ and a reproducibility of 1.2×10⁻⁸, with a DNR of detected signals of around 81 dB. It has been shown that PSDAVLL might be successfully used as a method for spectra-stable laser sources.

  7. Instantaneous formation of SiOx nanocomposite for high capacity lithium ion batteries by enhanced disproportionation reaction during plasma spray physical vapor deposition.

    Science.gov (United States)

    Tashiro, Tohru; Dougakiuchi, Masashi; Kambara, Makoto

    2016-01-01

    Nanocomposite SiO x particles have been produced by a single step plasma spray physical vapor deposition (PS-PVD) through rapid condensation of SiO vapors and the subsequent disproportionation reaction. Core-shell nanoparticles, in which 15 nm crystalline Si is embedded within the amorphous SiO x matrix, form under typical PS-PVD conditions, while 10 nm amorphous particles are formed when processed with an increased degree of non-equilibrium effect. Addition of CH 4 promotes reduction in the oxygen content x of SiO x , and thereby increases the Si volume in a nanocomposite particle. As a result, core-shell nanoparticles with x  = 0.46 as anode exhibit increased initial efficiency and the capacity of lithium ion batteries while maintaining cyclability. Furthermore, it is revealed that the disproportionation reaction of SiO is promoted in nanosized particles attaining increased Si diffusivity by two orders of magnitude compared to that in bulk, which facilitates instantaneous composite nanoparticle formation during PS-PVD.

  8. Simultaneous fabrication of laser-active colour centres and permanent microgratings in lithium fluoride by a single femtosecond pulse

    International Nuclear Information System (INIS)

    Kurobori, Toshio; Kawamura, Ken-ichi; Hirano, Masahiro; Hosono, Hideo

    2003-01-01

    We report, for the first time, simultaneous fabrication of laser-active F 2 and F 3 + colour centres in lithium fluoride and permanent periodic gratings with fringe spacings as fine as sub-micron size by two interfering infrared femtosecond (fs) laser pulses. In particular, the optical properties (absorption and luminescence) of F 2 and F 3 + colour centres produced by a single fs laser pulse are compared with those created by damage from radiation such as x-rays. The present technique of simultaneously fabricating laser-active colour centres and functional fine-periodic structures in photo-insensitive transparent materials may well be a useful method for making miniaturized optical devices. (letter to the editor)

  9. Vapor pressure of heat transfer fluids of absorption refrigeration machines and heat pumps: Binary solutions of lithium nitrate with methanol

    International Nuclear Information System (INIS)

    Safarov, Javid T.

    2005-01-01

    Vapor pressure p of LiNO 3 + CH 3 OH solutions at T = (298.15 to 323.15) K was reported, osmotic φ and activity coefficients γ; and activity of solvent a s have been evaluated. The experiments were carried out in molality range m = (0.18032 to 5.2369) mol . kg -1 . The Antoine equation was used for the empiric description of experimental vapor pressure results. The Pitzer-Mayorga model with inclusion of Archer's ionic strength dependence of the third virial coefficient was used for the description of calculated osmotic coefficients. The parameters of Archer extended Pitzer model were used for evaluation of activity coefficients

  10. Comparisons between a gas-phase model of silane chemical vapor deposition and laser-diagnostic measurements

    International Nuclear Information System (INIS)

    Breiland, W.G.; Coltrin, M.E.; Ho, P.

    1986-01-01

    Theoretical modeling and experimental measurements have been used to study gas-phase chemistry in the chemical vapor deposition (CVD) of silicon from silane. Pulsed laser Raman spectroscopy was used to obtain temperature profiles and to obtain absolute density profiles of silane during deposition at atmospheric and 6-Torr total pressures for temperatures ranging from 500 to 800 0 C. Laser-excited fluorescence was used to obtain relative density profiles of Si 2 during deposition at 740 0 C in helium with 0-12 Torr added hydrogen. These measurements are compared to predictions from the theoretical model of Coltrin, Kee, and Miller. The predictions agree qualitatively with experiment. These studies indicate that fluid mechanics and gas-phase chemical kinetics are important considerations in understanding the chemical vapor deposition process

  11. Regularly arranged indium islands on glass/molybdenum substrates upon femtosecond laser and physical vapor deposition processing

    Energy Technology Data Exchange (ETDEWEB)

    Ringleb, F.; Eylers, K.; Teubner, Th.; Boeck, T., E-mail: torsten.boeck@ikz-berlin.de [Leibniz-Institute for Crystal Growth, Max-Born-Straße 2, Berlin 12489 (Germany); Symietz, C.; Bonse, J.; Andree, S.; Krüger, J. [Bundesanstalt für Materialforschung und-prüfung (BAM), Unter den Eichen 87, Berlin 12205 (Germany); Heidmann, B.; Schmid, M. [Department of Physics, Freie Universität Berlin, Arnimalle 14, Berlin 14195 (Germany); Nanooptical Concepts for PV, Helmholtz Zentrum Berlin, Hahn-Meitner-Platz 1, Berlin 14109 (Germany); Lux-Steiner, M. [Nanooptical Concepts for PV, Helmholtz Zentrum Berlin, Hahn-Meitner-Platz 1, Berlin 14109 (Germany); Heterogeneous Material Systems, Helmholtz Zentrum Berlin, Hahn-Meitner-Platz 1, Berlin 14109 (Germany)

    2016-03-14

    A bottom-up approach is presented for the production of arrays of indium islands on a molybdenum layer on glass, which can serve as micro-sized precursors for indium compounds such as copper-indium-gallium-diselenide used in photovoltaics. Femtosecond laser ablation of glass and a subsequent deposition of a molybdenum film or direct laser processing of the molybdenum film both allow the preferential nucleation and growth of indium islands at the predefined locations in a following indium-based physical vapor deposition (PVD) process. A proper choice of laser and deposition parameters ensures the controlled growth of indium islands exclusively at the laser ablated spots. Based on a statistical analysis, these results are compared to the non-structured molybdenum surface, leading to randomly grown indium islands after PVD.

  12. Laser-drilled micro-hole arrays on polyurethane synthetic leather for improvement of water vapor permeability

    International Nuclear Information System (INIS)

    Wu, Y.; Wang, A.H.; Zheng, R.R.; Tang, H.Q.; Qi, X.Y.; Ye, B.

    2014-01-01

    Three kinds of lasers at 1064, 532 and 355 nm wavelengths respectively were adopted to construct micro-hole arrays on polyurethane (PU) synthetic leather with an aim to improve water vapor permeability (WVP) of PU synthetic leather. The morphology of the laser-drilled micro-holes was observed to optimize laser parameters. The WVP and slit tear resistance of the laser-drilled leather were measured. Results show that the optimized pulse energy for the 1064, 532 and 355 nm lasers are 0.8, 1.1 and 0.26 mJ, respectively. The diameters of the micro-holes drilled with the optimized laser pulse energy were about 20, 15 and 10 μm, respectively. The depths of the micro-holes drilled with the optimized pulse energy were about 21, 60 and 69 μm, respectively. Compared with the untreated samples, the highest WVP growth ratio was 38.4%, 46.8% and 53.5% achieved by the 1064, 532 and 355 nm lasers, respectively. And the highest decreasing ratio of slit tear resistance was 11.1%, 14.8%, and 22.5% treated by the 1064, 532 and 355 nm lasers, respectively. Analysis of the interaction mechanism between laser beams at three kinds of laser wavelengths and the PU synthetic leather revealed that laser micro-drilling at 355 nm wavelength displayed both photochemical ablation and photothermal ablation, while laser micro-drilling at 1064 and 532 nm wavelengths leaded to photothermal ablation only.

  13. Laser-drilled micro-hole arrays on polyurethane synthetic leather for improvement of water vapor permeability

    Science.gov (United States)

    Wu, Y.; Wang, A. H.; Zheng, R. R.; Tang, H. Q.; Qi, X. Y.; Ye, B.

    2014-06-01

    Three kinds of lasers at 1064, 532 and 355 nm wavelengths respectively were adopted to construct micro-hole arrays on polyurethane (PU) synthetic leather with an aim to improve water vapor permeability (WVP) of PU synthetic leather. The morphology of the laser-drilled micro-holes was observed to optimize laser parameters. The WVP and slit tear resistance of the laser-drilled leather were measured. Results show that the optimized pulse energy for the 1064, 532 and 355 nm lasers are 0.8, 1.1 and 0.26 mJ, respectively. The diameters of the micro-holes drilled with the optimized laser pulse energy were about 20, 15 and 10 μm, respectively. The depths of the micro-holes drilled with the optimized pulse energy were about 21, 60 and 69 μm, respectively. Compared with the untreated samples, the highest WVP growth ratio was 38.4%, 46.8% and 53.5% achieved by the 1064, 532 and 355 nm lasers, respectively. And the highest decreasing ratio of slit tear resistance was 11.1%, 14.8%, and 22.5% treated by the 1064, 532 and 355 nm lasers, respectively. Analysis of the interaction mechanism between laser beams at three kinds of laser wavelengths and the PU synthetic leather revealed that laser micro-drilling at 355 nm wavelength displayed both photochemical ablation and photothermal ablation, while laser micro-drilling at 1064 and 532 nm wavelengths leaded to photothermal ablation only.

  14. Experimental investigation on a diode-pumped cesium-vapor laser stably operated at continuous-wave and pulse regime.

    Science.gov (United States)

    Chen, Fei; Xu, Dongdong; Gao, Fei; Zheng, Changbin; Zhang, Kuo; He, Yang; Wang, Chunrui; Guo, Jin

    2015-05-04

    Employing a fiber-coupled diode-laser with a center wavelength of 852.25 nm and a line width of 0.17 nm, experimental investigation on diode-end-pumped cesium (Cs) vapor laser stably operated at continuous-wave (CW) and pulse regime is carried out. A 5 mm long cesium vapor cell filled with 60 kPa helium and 20 kPa ethane is used as laser medium. Using an output coupler with reflectivity of 48.79%, 1.26 W 894.57 nm CW laser is obtained at an incident pump power of 4.76 W, corresponding an optical-optical efficiency of 26.8% and a slope-efficiency of 28.8%, respectively. The threshold temperature is 67.5 °C. Stable pulsed cesium laser with a maximum average output power of 2.6 W is obtained at a repetition rate of 76 Hz, and the pulse repetition rate can be extend to 1 kHz with a pulse width of 18 μs.

  15. Measurement of the population densities in Gd atomic vapor using diode laser absorption spectroscopy in UV transitions

    International Nuclear Information System (INIS)

    Kwon, Duck Hee; Jung, E. C.; Ko, Kwang Hoon; Kim, Tack Soo

    2003-01-01

    We report on the ultraviolet laser absorption spectroscopy of atomic Gd at 394-554 nm where two transition lines are place very closely by using a frequency-doubled beam of external-cavity diode laser (ECDL). One is from 999.121 to 26337.071 cm -1 and the other from 0 to 25337.755 cm -1 . If two transition lines are placed closely within a continuous fine tuning range, the real-time measurement of the atomic excitation temperature is possible without any significant time consumption because at least two transition lines originating from different low-lying energy levels need to be investigated for the Boltzmann-plot. Since the spectral difference between the two transitions is only about 0.195 cm -1 (5.85 GHz), it is possible to record both the absorption spectra simultaneously as shown in Fig. 1. But the transition probabilities (or oscillator strengths) of these lines have not been measured accurately yet to the best of our knowledge. We report on the newly measured transition probabilities by analyzing their absorption spectra at known vapor density conditions. The simultaneous measurement of the atomic excitation temperature and the vapor density demonstrated. In addition we present another ultraviolet laser absorption spectroscopy of atomic Gd at 403.540 nm by means of a commercial blue diode laser and investigate the characteristics of the blue diode laser as well.

  16. Numerical simulation of transient, incongruent vaporization induced by high power laser

    International Nuclear Information System (INIS)

    Tsai, C.H.

    1981-01-01

    A mathematical model and numerical calculations were developed to solve the heat and mass transfer problems specifically for uranum oxide subject to laser irradiation. It can easily be modified for other heat sources or/and other materials. In the uranium-oxygen system, oxygen is the preferentially vaporizing component, and as a result of the finite mobility of oxygen in the solid, an oxygen deficiency is set up near the surface. Because of the bivariant behavior of uranium oxide, the heat transfer problem and the oxygen diffusion problem are coupled and a numerical method of simultaneously solving the two boundary value problems is studied. The temperature dependence of the thermal properties and oxygen diffusivity, as well as the highly ablative effect on the surface, leads to considerable non-linearities in both the governing differential equations and the boundary conditions. Based on the earlier work done in this laboratory by Olstad and Olander on Iron and on Zirconium hydride, the generality of the problem is expanded and the efficiency of the numerical scheme is improved. The finite difference method, along with some advanced numerical techniques, is found to be an efficient way to solve this problem

  17. Formation of long carbon chain molecules during laser vaporization of graphite

    International Nuclear Information System (INIS)

    Heath, J.R.; Zhang, Q.; O'Brien, S.C.; Curl, R.F.; Kroto, H.W.; Smalley, R.E.

    1987-01-01

    Graphite is laser vaporized into a He carrier gas containing various simple molecules such as H 2 , H 2 O, NH 3 , and CH 3 CN, supersonically expanded, and skimmed into a molecular beam, and the beam is interrogated by photoionization time-of-flight mass spectrometry. Without added reactants in the He carrier gas, C/sub n/ species up to n = 130 are readily observed. Two distributions separated at about n = 40 appear to be present with the low n species the focus of this work. In the presence of added reagents, new species appear as a result of reaction. These are satisfactorily explained on the basis that a significant proportion of the C/sub n/ species initially formed are reactive radicals with linear carbon chain structures which can readily add H, N, or CN at the ends to form relatively stable polyynes or cyanopolyynes. Some of the cyanopolyynes detected have also been observed in the interstellar medium, and circumstellar carbon condensation processes in the atmospheres of carbon-rich stars similar to those studied here are suggested as possible synthetic sources

  18. An efficient laser vaporization source for chemically modified metal clusters characterized by thermodynamics and kinetics

    Science.gov (United States)

    Masubuchi, Tsugunosuke; Eckhard, Jan F.; Lange, Kathrin; Visser, Bradley; Tschurl, Martin; Heiz, Ulrich

    2018-02-01

    A laser vaporization cluster source that has a room for cluster aggregation and a reactor volume, each equipped with a pulsed valve, is presented for the efficient gas-phase production of chemically modified metal clusters. The performance of the cluster source is evaluated through the production of Ta and Ta oxide cluster cations, TaxOy+ (y ≥ 0). It is demonstrated that the cluster source produces TaxOy+ over a wide mass range, the metal-to-oxygen ratio of which can easily be controlled by changing the pulse duration that influences the amount of reactant O2 introduced into the cluster source. Reaction kinetic modeling shows that the generation of the oxides takes place under thermalized conditions at less than 300 K, whereas metal cluster cores are presumably created with excess heat. These characteristics are also advantageous to yield "reaction intermediates" of interest via reactions between clusters and reactive molecules in the cluster source, which may subsequently be mass selected for their reactivity measurements.

  19. [Atomic Vapor Laser Isotope Separation (AVLIS) program]. Final report, [January--July 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-04

    This report summarizes work performed for the Atomic Vapor Laser Isotope Separation (AVLIS) program from January through July, 1992. Each of the tasks assigned during this period is described, and results are presented. Section I details work on sensitivity matrices for the UDS relay telescope. These matrices show which combination of mirror motions may be performed in order to effect certain changes in beam parameters. In Section II, an analysis is given of transmission through a clipping aperture on the launch telescope deformable mirror. Observed large transmission losses could not be simulated in the analysis. An EXCEL spreadsheet program designed for in situ analysis of UDS optical systems is described in Section III. This spreadsheet permits analysis of changes in beam first-order characteristics due to changes in any optical system parameter, simple optimization to predict mirror motions needed to effect a combination of changes in beam parameters, and plotting of a variety of first-order data. Optical systems may be assembled directly from OSSD data. A CODE V nonsequential model of the UDS optical system is described in Section IV. This uses OSSD data to build the UDS model; mirror coordinates may thus be verified. Section V summarizes observations of relay telescope performance. Possible procedures which allow more accurate assessment of relay telescope performance are given.

  20. Characterization studies of lithium vapour generated in heat pipe oven for the Plasma Wakefield Accelerator Experiment

    International Nuclear Information System (INIS)

    Mohandas, K.K.; Mahavar, Kanchan; Ajai Kumar; Kumar, Ravi A.V.

    2013-01-01

    Characterization and optimization studies of lithium vapor by white light as well as UV laser absorption were carried out as part of generation of photo ionized Li plasma for the Plasma Wake Field Acceleration Experiment. Temperature and buffer gas pressure dependency of the neutral density of lithium vapor was studied in detail. The line integrated neutral density of Li(n o L) was found to be of the order of 10 17 -10 18 cm -2 at heat pipe oven temperatures in the range from 600-800℃ which is sufficient to obtain the required 1013-1014 cm -3 plasma densities by photo ionization. (author)

  1. CO2 and Nd:YAP laser interaction with lithium disilicate and Zirconia dental ceramics: A preliminary study

    Science.gov (United States)

    Rocca, Jean-Paul; Fornaini, Carlo; Brulat-Bouchard, Nathalie; Bassel Seif, Samy; Darque-Ceretti, Evelyne

    2014-04-01

    Lithium disilicate and Zirconia ceramics offer a high level of accuracy when used in prosthetic dentistry. Their bonding using different resins is highly dependent on micro-mechanical interlocking and adhesive chemical bonding. Investigation of the performances of high strength ceramics when their surface is modified for chemical and mechanical bonding is then required. The aim of this study is to investigate the possibility of using laser for surface treatment of different high strength CAD/CAM ceramics and thus to improve their mechanical and chemical properties. Thirty two CAD/CAM ceramic discs were divided into two different groups: lithium disilicate ceramics (IPS e.max CAD®, Ivoclar, Vivadent, Italy) and Zirconia ceramics (IPS e.max ZirCAD®, Ivoclar, Vivadent, Italy). The Laser surface treatment was performed by Carbon Dioxide laser (Dream Pulse Laser®, Daeshin Enterprise Corp., Korea) at 20 W, 25 W and 30 W CW and by Neodymium Yttrium Aluminum Perovskite laser (Nd:YAP Lokki®, Lobel Medical, France) at 10 W and 30 Hz. Physical modifications of the irradiated ceramic discs were observed by scanning electron microscopy (SEM) and chemically analyzed by Energy-Dispersive Spectroscopy (EDS). Surface wettability was tested using the water drop test and the crystalline structure was investigated using X-ray diffraction (XRD). The macroscopic observation showed a shinier structure in all the groups, while at the SEM observation only CO2 25 W and 30 W treated groups showed cracks and fissures. In the conditions of this study, CO2 laser and Nd:YAP laser with the parameters used create chemical and physical surface modifications of the ceramics, indicating the possibility of an improvement in adhesion of the tested ceramics.

  2. Effects of momentum transfer on sizing of current collectors for lithium-ion batteries during laser cutting

    Science.gov (United States)

    Lee, Dongkyoung; Mazumder, Jyotirmoy

    2018-02-01

    One of the challenges of the lithium-ion battery manufacturing process is the sizing of electrodes with good cut surface quality. Poor cut surface quality results in internal short circuits in the cells and significant heat generation. One of the solutions that may improve the cut quality with a high cutting speed is laser cutting due to its high energy concentration, fast processing time, high precision, small heat affected zone, flexible range of laser power and contact free process. In order to utilize the advantages of laser electrode cutting, understanding the physical phenomena for each material is crucial. Thus, this study focuses on the laser cutting of current collectors, such as pure copper and aluminum. A 3D self-consistent mathematical model for the laser cutting, including fluid flow, heat transfer, recoil pressure, multiple reflections, capillary and thermo-capillary forces, and phase changes, is presented and solved numerically. Simulation results for the laser cutting are analyzed in terms of penetration time, depth, width, and absorptivity, based on these selected laser parameters. In addition, melt pool flow, melt pool geometry and temperature distribution are investigated.

  3. Vapor pressure of heat transfer fluids of absorption refrigeration machines and heat pumps: Binary solutions of lithium nitrate with methanol

    Energy Technology Data Exchange (ETDEWEB)

    Safarov, Javid T. [Heat and Refrigeration Techniques, Azerbaijan Technical University, Huseyn Javid Avn. 25, AZ1073 Baku (Azerbaijan)]. E-mail: javids@azdata.net

    2005-12-15

    Vapor pressure p of LiNO{sub 3} + CH{sub 3}OH solutions at T = (298.15 to 323.15) K was reported, osmotic {phi} and activity coefficients {gamma}; and activity of solvent a {sub s} have been evaluated. The experiments were carried out in molality range m = (0.18032 to 5.2369) mol . kg{sup -1}. The Antoine equation was used for the empiric description of experimental vapor pressure results. The Pitzer-Mayorga model with inclusion of Archer's ionic strength dependence of the third virial coefficient was used for the description of calculated osmotic coefficients. The parameters of Archer extended Pitzer model were used for evaluation of activity coefficients.

  4. Laser induced explosive vapor and cavitation resulting in effective irrigation of the root canal. Part 1: a visualization study.

    Science.gov (United States)

    Blanken, Jan; De Moor, Roeland Jozef Gentil; Meire, Maarten; Verdaasdonk, Rudolf

    2009-09-01

    Limited information exists regarding the induction of explosive vapor and cavitation bubbles in an endodontic rinsing solution. It is also not clear whether a fiber has to be moved in the irrigation solution or can be kept stationary. No information is available on safe power settings for the use of cavitation in the root canal. This study investigates the fluid movements and the mechanism of action caused by an Er,Cr:YSGG laser in a transparent root model. Glass models with an artificial root canal (15 mm long, with a 0.06 taper and apical diameter of 400 microm) were used for visualization and registration with a high-speed imaging technique (resolution in the microsecond range) of the creation of explosive vapor bubbles with an Er,Cr:YSGG laser at pulse energies of 75, 125, and 250 mJ at 20 Hz using a 200 microm fiber (Z2 Endolase). Fluid movement was investigated by means of dyes and visualization of the explosive vapor bubbles, and as a function of pulse energy and distance of the fiber tip to the apex. The recordings in the glass model show the creation of expanding and imploding vapor bubbles with secondary cavitation effects. Dye is flushed out of the canal and replaced by surrounding fluid. It seems not necessary to move the fiber close to the apex. Imaging suggests that the working mechanism of an Er,Cr:YSGG laser in root canal treatment in an irrigation solution can be attributed to cavitation effects inducing high-speed fluid motion into and out the canal.

  5. Soft-Bake Purification of SWCNTs Produced by Pulsed Laser Vaporization

    Science.gov (United States)

    Yowell, Leonard; Nikolaev, Pavel; Gorelik, Olga; Allada, Rama Kumar; Sosa, Edward; Arepalli, Sivaram

    2013-01-01

    The "soft-bake" method is a simple and reliable initial purification step first proposed by researchers at Rice University for single-walled carbon nanotubes (SWCNT) produced by high-pressure carbon mon oxide disproportionation (HiPco). Soft-baking consists of annealing as-produced (raw) SWCNT, at low temperatures in humid air, in order to degrade the heavy graphitic shells that surround metal particle impurities. Once these shells are cracked open by the expansion and slow oxidation of the metal particles, the metal impurities can be digested through treatment with hydrochloric acid. The soft-baking of SWCNT produced by pulsed-laser vaporization (PLV) is not straightforward, because the larger average SWCNT diameters (.1.4 nm) and heavier graphitic shells surrounding metal particles call for increased temperatures during soft-bake. A part of the technology development focused on optimizing the temperature so that effective cracking of the graphitic shells is balanced with maintaining a reasonable yield, which was a critical aspect of this study. Once the ideal temperature was determined, a number of samples of raw SWCNT were purified using the soft-bake method. An important benefit to this process is the reduced time and effort required for soft-bake versus the standard purification route for SWCNT. The total time spent purifying samples by soft-bake is one week per batch, which equates to a factor of three reduction in the time required for purification as compared to the standard acid purification method. Reduction of the number of steps also appears to be an important factor in improving reproducibility of yield and purity of SWCNT, as small deviations are likely to get amplified over the course of a complicated multi-step purification process.

  6. Tissue ablation after 120W greenlight laser vaporization and bipolar plasma vaporization of the prostate: a comparison using transrectal three-dimensional ultrasound volumetry

    Science.gov (United States)

    Kranzbühler, Benedikt; Gross, Oliver; Fankhauser, Christian D.; Hefermehl, Lukas J.; Poyet, Cédric; Largo, Remo; Müntener, Michael; Seifert, Hans-Helge; Zimmermann, Matthias; Sulser, Tullio; Müller, Alexander; Hermanns, Thomas

    2012-02-01

    Introduction and objectives: Greenlight laser vaporization (LV) of the prostate is characterized by simultaneous vaporization and coagulation of prostatic tissue resulting in tissue ablation together with excellent hemostasis during the procedure. It has been reported that bipolar plasma vaporization (BPV) of the prostate might be an alternative for LV. So far, it has not been shown that BPV is as effective as LV in terms of tissue ablation or hemostasis. We performed transrectal three-dimensional ultrasound investigations to compare the efficiency of tissue ablation between LV and BPV. Methods: Between 11.2009 and 5.2011, 50 patients underwent pure BPV in our institution. These patients were matched with regard to the pre-operative prostate volume to 50 LV patients from our existing 3D-volumetry-database. Transrectal 3D ultrasound and planimetric volumetry of the prostate were performed pre-operatively, after catheter removal, 6 weeks and 6 months. Results: Median pre-operative prostate volume was not significantly different between the two groups (45.3ml vs. 45.4ml; p=1.0). After catheter removal, median absolute volume reduction (BPV 12.4ml, LV 6.55ml) as well as relative volume reduction (27.8% vs. 16.4%) were significantly higher in the BPV group (p<0.001). After six weeks (42.9% vs. 33.3%) and six months (47.2% vs. 39.7%), relative volume reduction remained significantly higher in the BPV group (p<0.001). Absolute volume reduction was non-significantly higher in the BPV group after six weeks (18.4ml, 13.8ml; p=0.051) and six months (20.8ml, 18ml; p=0.3). Clinical outcome parameters improved significantly in both groups without relevant differences between the groups. Conclusions: Both vaporization techniques result in efficient tissue ablation with initial prostatic swelling. BPV seems to be superior due to a higher relative volume reduction. This difference had no clinical impact after a follow-up of 6M.

  7. Hydrogen Outgassing from Lithium Hydride

    Energy Technology Data Exchange (ETDEWEB)

    Dinh, L N; Schildbach, M A; Smith, R A; Balazs1, B; McLean II, W

    2006-04-20

    Lithium hydride is a nuclear material with a great affinity for moisture. As a result of exposure to water vapor during machining, transportation, storage and assembly, a corrosion layer (oxide and/or hydroxide) always forms on the surface of lithium hydride resulting in the release of hydrogen gas. Thermodynamically, lithium hydride, lithium oxide and lithium hydroxide are all stable. However, lithium hydroxides formed near the lithium hydride substrate (interface hydroxide) and near the sample/vacuum interface (surface hydroxide) are much less thermally stable than their bulk counterpart. In a dry environment, the interface/surface hydroxides slowly degenerate over many years/decades at room temperature into lithium oxide, releasing water vapor and ultimately hydrogen gas through reaction of the water vapor with the lithium hydride substrate. This outgassing can potentially cause metal hydriding and/or compatibility issues elsewhere in the device. In this chapter, the morphology and the chemistry of the corrosion layer grown on lithium hydride (and in some cases, its isotopic cousin, lithium deuteride) as a result of exposure to moisture are investigated. The hydrogen outgassing processes associated with the formation and subsequent degeneration of this corrosion layer are described. Experimental techniques to measure the hydrogen outgassing kinetics from lithium hydride and methods employing the measured kinetics to predict hydrogen outgassing as a function of time and temperature are presented. Finally, practical procedures to mitigate the problem of hydrogen outgassing from lithium hydride are discussed.

  8. Structural, microstructural and transport properties study of lanthanum lithium titanium perovskite thin films grown by Pulsed Laser Deposition

    International Nuclear Information System (INIS)

    Maqueda, O.; Sauvage, F.; Laffont, L.; Martinez-Sarrion, M.L.; Mestres, L.; Baudrin, E.

    2008-01-01

    Lanthanum lithium titanate thin films were grown by Pulsed Laser Deposition. La 0.57 Li 0.29 TiO 3 dense films with smooth surfaces were obtained after optimization of the growth parameters. Such films deposited at 700 deg. C under 15 Pa are nano-crystalline with domains corresponding to the cubic and tetragonal modifications of this phase. In relation to the measured conductivities/activation energy and to previous works, we clearly underlined that the films of practical interest, prepared at relatively low temperature, are predominantly formed from the tetragonal ordered phase

  9. Laser scattering in a hanging drop vapor diffusion apparatus for protein crystal growth in a microgravity environment

    Science.gov (United States)

    Casay, G. A.; Wilson, W. W.

    1992-01-01

    One type of hardware used to grow protein crystals in the microgravity environment aboard the U.S. Space Shuttle is a hanging drop vapor diffusion apparatus (HDVDA). In order to optimize crystal growth conditions, dynamic control of the HDVDA is desirable. A critical component in the dynamically controlled system is a detector for protein nucleation. We have constructed a laser scattering detector for the HDVDA capable of detecting the nucleation stage. The detector was successfully tested for several scatterers differing in size using dynamic light scattering techniques. In addition, the ability to detect protein nucleation using the HDVDA was demonstrated for lysozyme.

  10. Decrease in lower level density due to cooling of gas temperature by thermal dissociation of hydrogen in copper vapor laser

    International Nuclear Information System (INIS)

    Watanabe, Ikuo; Hayashi, Kazuo; Iseki, Yasushi; Suzuki, Setsuo; Noda, Etsuo; Morimiya, Osamu

    1995-01-01

    A gas temperature calculation is carried out in the copper vapor laser (CVL) with a beam diameter of 80 mm in the case of H 2 addition into the Ne buffer gas. The on-axis gas temperature decreases to 2800K with 1% concentration of H 2 , whereas the gas temperature is 3400K without H 2 . The on-axis lower level density decreases due to the cooling of the gas temperature. This decrease in the lower level density is thought to bring about a non annular beam profile in the case of H 2 addition. (author)

  11. Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

    2010-01-01

    Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

  12. Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

    2010-05-01

    Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

  13. Laser beam absorption study of a 238U(5L60) vapor obtained with a hollow cathode lamp

    International Nuclear Information System (INIS)

    Gagne, J.M.; Leblanc, B.; Mongeau, B.; Carleer, M.; Bertrand, L.

    1979-01-01

    The density of U atoms in the 5 L 0 6 ground state present in a vapor of this element from a hollow cathode lamp has been measured using laser absorption spectroscopy. The influence of the carrier gases (Ar, Kr, Xe) on the density, the absorption coefficient profiles, and on the ratio of U atoms to the dissipated electrical power has been investigated. It has been found that, in our range of operating conditions, the xenon gas is the most efficient. With xenon, a density of 2.2 x 10 12 cm -3 ground-state U atoms is obtained when the lamp dissipates 40 W of electrical power

  14. Mw Spectroscopy Coupled with Ultrafast UV Laser Vaporization: {RIBOSE} Found in the Gas Phase

    Science.gov (United States)

    Cocinero, Emilio J.; Ecija, Patricia; Basterretxea, Francisco J.; Fernandez, Jose A.; Castano, Fernando; Lesarri, Alberto; Grabow, Jens-Uwe

    2012-06-01

    Sugars are aldoses or ketoses with multiple hydroxy groups which have been elusive to spectroscopic studies. Here we report a rotational study of the aldopentose ribose. According to any standard textbook aldopentoses can exhibit either linear forms, cyclic five-membered (furanose) structures or six-membered (pyranose) rings, occurring either as α- or β- anomers depending on the orientation of the hydroxy group at C-1 (anomeric carbon). β-Furanose is predominant in ribonucleosides, RNA, ATP and other biochemically relevant derivatives, but is β-furanose the native form also of free ribose? Recent condensed-phase X-ray and older NMR studies delivered conflicting results. In order to solve this question we conducted a microwave study on D-ribose that, owing to ultrafast UV laser vaporization, has become the first C-5 sugar observed with rotational resolution. The spectrum revealed six conformations of free ribose, preferentially adopting β-pyranose chairs as well as higher-energy α-pyranose forms. The method also allowed for unambiguous distinction between different orientations of the hydroxy groups, which stabilize the structures by cooperative hydrogen-bond networks. No evidence was observed of the α-/β-furanoses or linear forms found in the biochemical derivatives. i) D. Šišak, L. B. McCusker, G. Zandomeneghi, B. H. Meier, D. Bläser, R. Boese, W. B. Schweizer, R. Gylmour and J. D. Dunitz Angew. Chem. Int. Ed. 49, 4503, 2010. ii) W. Saenger Angew. Chem. Int. Ed. 49, 6487, 2010. i) M. Rudrum, and D. F. Shaw, J. Chem. Soc. 52, 1965. ii) R. U. Lemieux and J. D. Stevens Can. J. Chem. 44, 249, 1966. iii) E. Breitmaier and U. Hollstein Org. Magn. Reson. 8, 573, 1976. E. J. Cocinero, A. Lesarri, P. Écija, F. J. Basterretxea, J. U. Grabow, J. A. Fernández and F. Castaño Angew. Chem. Int. Ed. in press: DOI: 10.1002/anie.201107973, 2012.

  15. Using a helium--neon laser to convert infrared radiation to visible emission on lithium niobate crystals

    Energy Technology Data Exchange (ETDEWEB)

    Aurtyunyan, E.A.; Kostanyan, R.B.; Mkrtchyan, V.S.; Mkrtchyan, M.A.

    1975-01-01

    The conversion of infrared emission to the visible region was investigated by mixing with helium-neon laser emission in lithium niobate crystals. The infrared source was a Globar, and the laser was the LG-75. Emission of the sum frequencies was filtered out. The spectral composition of the converted radiation was analyzed by the ISP-51 spectrograph with an FEU-79 photomultiplier at the output. The amplified photomultiplier signal was recorded by the ChZ-33 frequency meter. By varying the angle between the optical axis of the crystal and the incident emission, infrared radiation in the 1.75 to 3.3 ..mu..m wavelength band could be converted to visible emission. It is suggested that measurement of the wavelength of converted emission might be used to study the distribution of concentration nonhomogeneities in crystals.

  16. 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...

  17. Vapor phase coatings of metals and organics for laser fusion target applications

    International Nuclear Information System (INIS)

    Simonsic, G.A.; Powell, B.W.

    Techniques for applying a variety of metal and organic coatings to 50- to 500 μm diameter glass micro-balloons are discussed. Coating thicknesses vary from 1- to 10 μm. Physical vapor deposition (PVD), chemical vapor deposition (CVD), and electrolytic and electroless plating are some of the techniques being evaluated for metal deposition. PVD and glow discharge polymerization are being used for the application of organic coatings. (U.S.)

  18. CO2 laser vaporization in the treatment of cervical human papillomavirus infection in women with abnormal Papanicolaou smears

    DEFF Research Database (Denmark)

    Ruge, S; Felding, C; Skouby, S O

    1992-01-01

    In a randomized study, we have evaluated the treatment of cervical human papillomavirus (HPV) lesions by CO2 laser vaporization. Fifty patients with abnormal Papanicolaou smears and histological evidence of cervical HPV infection associated or not with cervical intraepithelial neoplasia (CIN) grade...... I were randomized to either a treatment or a control group. The cervical swabs were obtained every 3 months in both groups and examined for HPV type 16 DNA by the polymerase chain reaction. After a follow-up period of 12 months no significant differences were found between the laser treatment...... in their cervical smears at 12 months' follow-up was identical in the two groups, supporting the hypothesis that HPV is a persistent infection during which the virus is widespread in the vaginal epithelium....

  19. Water-vapor absorption line measurements in the 940-nm band by using a Raman-shifted dye laser

    Science.gov (United States)

    Chu, Zhiping; Wilkerson, Thomas D.; Singh, Upendra N.

    1993-01-01

    We report water-vapor absorption line measurements that are made by using the first Stokes radiation (930-982 nm) with HWHM 0.015/cm generated by a narrow-linewidth, tunable dye laser. Forty-five absorption line strengths are measured with an uncertainty of 6 percent and among them are fourteen strong lines that are compared with previous measurements for the assessment of spectral purity of the light source. Thirty air-broadened linewidths are measured with 8 percent uncertainty at ambient atmospheric pressure with an average of 0.101/cm. The lines are selected for the purpose of temperature-sensitive or temperature-insensitive lidar measurements. Results for these line strengths and linewidths are corrected for broadband radiation and finite laser linewidth broadening effects and compared with the high-resolution transmission molecular absorption.

  20. Direct analysis of intact biological macromolecules by low-energy, fiber-based femtosecond laser vaporization at 1042 nm wavelength with nanospray postionization mass spectrometry.

    Science.gov (United States)

    Shi, Fengjian; Flanigan, Paul M; Archer, Jieutonne J; Levis, Robert J

    2015-03-17

    A fiber-based laser with a pulse duration of 435 fs and a wavelength of 1042 nm was used to vaporize biological macromolecules intact from the condensed phase into the gas phase for nanospray postionization and mass analysis. Laser vaporization of dried standard protein samples from a glass substrate by 10 Hz bursts of 20 pulses having 10 μs pulse separation and energy resulted in signal comparable to a metal substrate. The protein signal observed from an aqueous droplet on a glass substrate was negligible compared to either a droplet on metal or a thin film on glass. The mass spectra generated from dried and aqueous protein samples by the low-energy, fiber laser were similar to the results from high-energy (500 μJ), 45-fs, 800-nm Ti:sapphire-based femtosecond laser electrospray mass spectrometry (LEMS) experiments, suggesting that the fiber-based femtosecond laser desorption mechanism involves a nonresonant, multiphoton process, rather than thermal- or photoacoustic-induced desorption. Direct analysis of whole blood performed without any pretreatment resulted in features corresponding to hemoglobin subunit-heme complex ions. The observation of intact molecular ions with low charge states from protein, and the tentatively assigned hemoglobin α subunit-heme complex from blood suggests that fiber-based femtosecond laser vaporization is a "soft" desorption source at a laser intensity of 2.39 × 10(12) W/cm(2). The low-energy, turnkey fiber laser demonstrates the potential of a more robust and affordable laser for femtosecond laser vaporization to deliver biological macromolecules into the gas phase for mass analysis.

  1. Thulium fiber laser-induced vapor bubble dynamics using bare, tapered, ball, hollow steel, and muzzle brake fiber optic tips

    Science.gov (United States)

    Gonzalez, David A.; Hardy, Luke A.; Hutchens, Thomas C.; Irby, Pierce B.; Fried, Nathaniel M.

    2018-03-01

    This study characterizes laser-induced vapor bubble dynamics for five different distal fiber optic tip configurations, to provide insight into stone retropulsion commonly experienced during laser ablation of kidney stones. A thulium fiber laser with 1908-nm wavelength delivered 34-mJ energy per pulse at 500-μs pulse duration through five different fibers such as 100-μm-core / 170-μm-OD bare fiber tip, 150- to 300-μm-core tapered fiber tip, 100-μm-core / 300-μm-OD ball tip fiber, 100-μm-core / 340-μm-OD hollow steel tip fiber, and 100-μm-core / 560-μm-OD muzzle brake fiber tip. A high-speed camera with 10-μm-spatial and 9.5-μs-temporal resolution was used to image the vapor bubble dynamics. A needle hydrophone measured pressure transients in the forward (0 deg) and side (90 deg) directions while placed at a 6.8 ± 0.4 mm distance from the distal fiber tip. Maximum bubble dimensions (width/length) averaged 0.7/1.5, 1.0/1.6, 0.5/1.1, 0.8/1.9, and 0.7 / 1.5 mm, for bare, tapered, ball, hollow steel, and muzzle brake fiber tips, respectively (n = 5). The hollow steel tip exhibited the most elongated vapor bubble shape, translating into increased forward pressure in this study and consistent with higher stone retropulsion in previous reports. Relative pressures (a.u.) in (forward/side) directions averaged 1.7/1.6, 2.0/2.0, 1.4/1.2, 6.8/1.1, and 0.3/1.2, for each fiber tip (n = 5). For the hollow steel tip, forward pressure was 4 × higher than for the bare fiber. For the muzzle brake fiber tip, forward pressure was 5 × lower than the bare fiber. Bubble dimensions and pressure measurements demonstrated that the muzzle brake fiber tip reduced forward pressure by partially venting vapors through the portholes, which is consistent with the observation of lower stone retropulsion in previous reports.

  2. MoXy fiber with active cooling cap for bovine prostate vaporization with high power 200W 532 nm laser

    Science.gov (United States)

    Peng, Steven Y.; Kang, Hyun Wook; Pirzadeh, Homa; Stinson, Douglas

    2011-03-01

    A novel MoXyTM fiber delivery device with Active Cooling Cap (ACCTM) is designed to transmit up to 180W of 532 nm laser light to treat benign prostatic hyperplasia (BPH). Under such high power tissue ablation, effective cooling is key to maintaining fiber power transmission and ensuring the reliability of the fiber delivery device To handle high power and reduce fiber degradation, the MoXy fiber features a larger core size (750 micrometer) and an internal fluid channel to ensure better cooling of the fiber tip to prevent the cap from burning, detaching, or shattering during the BPH treatment. The internal cooling channel was created with a metal cap and tubing that surrounds the optical fiber. In this study MoXy fibers were used to investigate the effect of power levels of 120 and 200 W on in-vitro bovine prostate ablation using a 532 nm XPSTM laser system. For procedures requiring more than 100 kJ, the MoXy fiber at 200W removed tissue at twice the rate of the current HPS fiber at 120W. The fiber maintained a constant tissue vaporization rate during the entire tissue ablation process. The coagulation at 200W was about 20% thicker than at 120W. In conclusion, the new fibers at 200W doubled the tissue removal rate, maintained vaporization efficiency throughout delivery of 400kJ energy, and induced similar coagulation to the existing HPS fiber at 120W.

  3. Electrochemical performance of LiFePO4 modified by pressure-pulsed chemical vapor infiltration in lithium-ion batteries

    International Nuclear Information System (INIS)

    Li Jianling; Suzuki, Tomohiro; Naga, Kazuhisa; Ohzawa, Yoshimi; Nakajima, Tsuyoshi

    2007-01-01

    Using the pressure-pulsed chemical vapor infiltration (PCVI) technique, pyrolytic carbon (pyrocarbon) films were deposited on the surface of LiFePO 4 particles for cathode material of lithium-ion batteries. The electrochemical performance of the original LiFePO 4 and PCVIed LiFePO 4 materials was evaluated using a three electrodes cell by galvanostatic charging/discharging at 25, 40 and 55 deg. C, respectively. Morphology and structure of LiFePO 4 were analyzed by SEM, XRD and Raman. The resulting carbon contents at 500, 1000, 2000, 3000 and 5000 pulses were 2.7, 4.7, 9.5, 15.1 and 19.4%, respectively and these samples were abbreviated as 500P, 1000P, 2000P, 3000P and 5000P, respectively. All the PCVIed samples exhibited excellent rate performance. The tendency was more and more obvious with the increase of the current densities. The specific capacities of 500P, 1000P and 2000P were maintained at 117, 124 and 132 mAh g -1 , respectively, which were 120.8, 264.7 and 29.47% larger than those of corresponding original LiFePO 4 , respectively, at a 5C rate at 55 deg. C. The EIS measurement showed that electrochemical reaction resistance (R ct ) of PCVIed LiFePO 4 were obviously decreased, indicating a fast kinetics compared to the original LiFePO 4 . The cycle ability of the 2000P sample was tested at 25 deg. C and C/2 rate. The cell was cycled for 150 cycles and no obviously capacity fade was observed. Its specific capacity of 115 mAh g -1 at 150th cycle is 1.7 times higher than that of original LiFePO 4

  4. Electrochemical performance of LiFePO{sub 4} modified by pressure-pulsed chemical vapor infiltration in lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li Jianling [Department of Physical Chemistry, University of Science and Technology Beijing, No. 30 College Road, Haidian District, Beijing 100083 (China); Department of Applied Chemistry, Aichi Institute of Technology, Yachigusa 1247, Yakusa-cho, Toyota 470-0392 (Japan)], E-mail: lijianling@metall.ustb.edu.cn; Suzuki, Tomohiro; Naga, Kazuhisa; Ohzawa, Yoshimi; Nakajima, Tsuyoshi [Department of Applied Chemistry, Aichi Institute of Technology, Yachigusa 1247, Yakusa-cho, Toyota 470-0392 (Japan)

    2007-09-25

    Using the pressure-pulsed chemical vapor infiltration (PCVI) technique, pyrolytic carbon (pyrocarbon) films were deposited on the surface of LiFePO{sub 4} particles for cathode material of lithium-ion batteries. The electrochemical performance of the original LiFePO{sub 4} and PCVIed LiFePO{sub 4} materials was evaluated using a three electrodes cell by galvanostatic charging/discharging at 25, 40 and 55 deg. C, respectively. Morphology and structure of LiFePO{sub 4} were analyzed by SEM, XRD and Raman. The resulting carbon contents at 500, 1000, 2000, 3000 and 5000 pulses were 2.7, 4.7, 9.5, 15.1 and 19.4%, respectively and these samples were abbreviated as 500P, 1000P, 2000P, 3000P and 5000P, respectively. All the PCVIed samples exhibited excellent rate performance. The tendency was more and more obvious with the increase of the current densities. The specific capacities of 500P, 1000P and 2000P were maintained at 117, 124 and 132 mAh g{sup -1}, respectively, which were 120.8, 264.7 and 29.47% larger than those of corresponding original LiFePO{sub 4}, respectively, at a 5C rate at 55 deg. C. The EIS measurement showed that electrochemical reaction resistance (R{sub ct}) of PCVIed LiFePO{sub 4} were obviously decreased, indicating a fast kinetics compared to the original LiFePO{sub 4}. The cycle ability of the 2000P sample was tested at 25 deg. C and C/2 rate. The cell was cycled for 150 cycles and no obviously capacity fade was observed. Its specific capacity of 115 mAh g{sup -1} at 150th cycle is 1.7 times higher than that of original LiFePO{sub 4}.

  5. The influence of water vapor on atmospheric exchange measurements with an ICOS* based Laser absorption analyzer

    Science.gov (United States)

    Bunk, Rüdiger; Quan, Zhi; Wandel, Matthias; Yi, Zhigang; Bozem, Heiko; Kesselmeier, Jürgen

    2014-05-01

    Carbonyl sulfide and carbon monoxide are both atmospheric trace gases of high interest. Recent advances in the field of spectroscopy have enabled instruments that measure the concentration of the above and other trace gases very fast and with good precision. Increasing the effective path length by reflecting the light between two mirrors in a cavity, these instruments reach impressive sensitivities. Often it is possible to measure the concentration of more than one trace gas at the same time. The OCS/CO2 Analyzer by LGR (Los Gatos Research, Inc.) measures the concentration of water vapor [H2O], carbonyl sulfide [COS], carbon dioxide [CO2] and carbon monoxide [CO] simultaneously. For that the cavity is saturated with light, than the attenuation of light is measured as in standard absorption spectroscopy. The instrument proved to be very fast with good precision and to be able to detect even very low concentrations, especially for COS (as low as 30ppt in the case of COS). However, we observed a rather strong cross sensitivity to water vapor. Altering the water vapor content of the sampled air with two different methods led to a change in the perceived concentration of COS, CO and CO2. This proved especially problematic for enclosure (cuvette) measurements, where the concentrations of one of the above species in an empty cuvette are compared to the concentration of another cuvette containing a plant whose exchange of trace gases with the atmosphere is of interest. There, the plants transpiration leads to a large difference in water vapor content between the cuvettes and that in turn produces artifacts in the concentration differences between the cuvettes for the other above mentioned trace gases. For CO, simultaneous measurement with a UV-Emission Analyzer (AL 5002, Aerolaser) and the COS/CO Analyzer showed good agreement of perceived concentrations as long as the sample gas was dry and an increasing difference in perceived concentration when the sample gas was

  6. Fabrication of binder-free graphene-SnO{sub 2} electrodes by laser introduced conversion of precursors for lithium secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xiaoxiao, E-mail: xlu@zjut.edu.cn [College of Materials & Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Wu, Guolong [Institute of Laser Advanced Manufacturing, Zhejiang University of Technology, Hangzhou 310014 (China); Xiong, Qinqin; Qin, Haiying [College of Materials & Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Wang, Weibin [Institute of Laser Advanced Manufacturing, Zhejiang University of Technology, Hangzhou 310014 (China); Luo, Fang, E-mail: luofang@zjut.edu.cn [Institute of Laser Advanced Manufacturing, Zhejiang University of Technology, Hangzhou 310014 (China); College of Zhijiang, Zhejiang University of Technology, Hangzhou 310001 (China)

    2017-06-01

    Highlights: • Binder-free graphene-SnO{sub 2} electrodes were prepared by a laser irradiation method. • Laser irradiation can well control the conversion of precursors. • As-prepared electrodes present high lithium storage capacity with good cyclablity. - Abstract: Binder-free graphene-SnO{sub 2} electrodes were prepared by laser introduced conversion of precursor (mixture of graphene oxide and stannic oxide sol) coatings on a copper film. The evolution of the microstructure, thermal stability, morphologies and sheet resistance has been studied as a function of laser fluences. It was shown that the conversion of precursors is mainly attributed to the photothermic effect, and a laser fluence of 69.3 J cm{sup −2} is the best condition for sample preparation. When the as-prepared electrode used as an anode for lithium ion batteries, it has been demonstrated with a high lithium storage capacity and good cycling stability. A high capacity of around 700 mAh g{sup −1} can be retained after 50 cycles at a current density of 100 mA g{sup −1}, and even after 400 cycles the specific capacity steadied to around 690 mAh g{sup −1}. Such electrodes have a short preparing procedure and good electrochemical performance, so the fabrication method adopted here could be referable for industrial continuous production.

  7. Thulium fiber laser induced vapor bubbles using bare, tapered, ball, hollow steel, and muzzle brake fiber optic tips

    Science.gov (United States)

    Gonzalez, David A.; Hardy, Luke A.; Hutchens, Thomas C.; Irby, Pierce B.; Fried, Nathaniel M.

    2018-02-01

    This study characterizes laser-induced vapor bubbles for five distal fiber optic tip configurations, to provide insight into stone retropulsion experienced during laser ablation of kidney stones. A TFL with 1908-nm wavelength delivered 34 mJ energy per pulse at 500-μs pulse duration through five different fibers: 100-μm-core/170-μm-OD bare fiber tip, 150-μm- to 300-μm-core tapered fiber tip, 100-μm-core/300-μm-OD ball tip fiber, 100-μm-core/340- μm-OD hollow steel tip fiber, and 100-μm-core/560-μm-OD muzzle brake fiber tip. A high speed camera with 10- μm spatial and 9.5-μs temporal resolution imaged vapor bubble dynamics. A needle hydrophone measured pressure transients in forward (0°) and side (90°) directions while placed at a 6.8 +/- 0.4 mm distance from fiber tip. Maximum bubble dimensions (width/length) averaged 0.7/1.5, 1.0/1.6, 0.5/1.1, 0.8/1.9, and 0.7/1.5 mm, for bare, tapered, ball, hollow steel, and muzzle tips, respectively (n=5). The hollow steel tip exhibited the most elongated vapor bubble shape, translating into increased forward pressure in this study and consistent with higher stone retropulsion in previous reports. Relative pressures (a.u.) in (forward/side) directions averaged 1.7/1.6, 2.0/2.0, 1.4/1.2, 6.8/1.1, and 0.3/1.2, for each fiber tip (n=5). For hollow steel tip, forward pressure was 4× higher than for bare fiber. For the muzzle brake fiber tip, forward pressure was 5× lower than for bare fiber. Bubble dimensions and pressure measurements demonstrated that the muzzle tip reduced forward pressure by partially venting vapors through side holes, consistent with lower stone retropulsion observed in previous reports.

  8. Change the morphology of lithium oxides by Nd-Yag laser beam to use as a sand in water-cooled reactors

    Science.gov (United States)

    Karwi, Abbas Ali Mahmmod

    2018-04-01

    Laser has many attractive specifications which made it adaptable for material processing. Laser has been taken as a modern heat treatment source to prevent the formation of non-protective oxide layer with intensity equals to (1.31×105 w/cm2), lasing time equals to (300 µs), wave length equals to (1.063 µm), and the spot radius equals to (125 µm). Lithium is depleted through the conventional heat treatment processes. The main factors affected on lithium depletion are temperature and time. Lithium kept as a solid solution at casting method. Micro hardness of the affected zone reaches to acceptable values for various ageing times and hardening depths. The main conventional heat treatment processes are; homogenization, solution heat treatment, and ageing. Alloys prepared with the specific amounts of lithium concentration (2-2.5%). Oxides with different shapes are formed. Temperature distribution, heating, and cooling rates used externally and internally to see the effect of pulse generation by laser on bulk body.

  9. Dynamics of vapor plume in transient keyhole during laser welding of stainless steel: Local evaporation, plume swing and gas entrapment into porosity

    Science.gov (United States)

    Pang, Shengyong; Chen, Xin; Shao, Xinyu; Gong, Shuili; Xiao, Jianzhong

    2016-07-01

    In order to better understand the local evaporation phenomena of keyhole wall, vapor plume swing above the keyhole and ambient gas entrapment into the porosity defects, the 3D time-dependent dynamics of the metallic vapor plume in a transient keyhole during fiber laser welding is numerically investigated. The vapor dynamical parameters, including the velocity and pressure, are successfully predicted and obtain good agreements with the experimental and literature data. It is found that the vapor plume flow inside the keyhole has complex multiple directions, and this various directions characteristic of the vapor plume is resulted from the dynamic evaporation phenomena with variable locations and orientations on the keyhole wall. The results also demonstrate that because of this dynamic local evaporation, the ejected vapor plume from the keyhole opening is usually in high frequency swinging. The results further indicate that the oscillation frequency of the plume swing angle is around 2.0-8.0 kHz, which is of the same order of magnitude with that of the keyhole depth (2.0-5.0 kHz). This consistency clearly shows that the swing of the ejected vapor plume is closely associated with the keyhole instability during laser welding. Furthermore, it is learned that there is usually a negative pressure region (several hundred Pa lower than the atmospheric pressure) of the vapor flow around the keyhole opening. This pressure could lead to a strong vortex flow near the rear keyhole wall, especially when the velocity of the ejected metallic vapor from the keyhole opening is high. Under the effect of this flow, the ambient gas is involved into the keyhole, and could finally be entrapped into the bubbles within a very short time (keyhole.

  10. Single-photon cesium Rydberg excitation spectroscopy using 318.6-nm UV laser and room-temperature vapor cell.

    Science.gov (United States)

    Wang, Jieying; Bai, Jiandong; He, Jun; Wang, Junmin

    2017-09-18

    We demonstrate a single-photon Rydberg excitation spectroscopy of cesium (Cs) atoms in a room-temperature vapor cell. Cs atoms are excited directly from 6S 1/2 ground state to nP 3/2 (n = 70 - 100) Rydberg states with a 318.6 nm ultraviolet (UV) laser, and Rydberg excitation spectra are obtained by transmission enhancement of a probe beam resonant to Cs 6S 1/2 , F = 4 - 6P 3/2 , F' = 5 transition as partial population on F = 4 ground state are transferred to Rydberg state. Analysis reveals that the observed spectra are velocity-selective spectroscopy of Rydberg state, from which the amplitude and linewidth influenced by lasers' Rabi frequency have been investigated. Fitting to energies of Cs nP 3/2 (n = 70 -100) states, the determined quantum defect is 3.56671(42). The demodulated spectra can also be employed as frequency references to stabilize the UV laser frequency to specific Cs Rydberg transition.

  11. A study of the lasing of dyes under the influence of emission from a copper vapor laser

    Energy Technology Data Exchange (ETDEWEB)

    Danilova, V I; Kopylova, T N; Maier, G V; Masarnovskii, L V; Soldatov, A N; Sukhanov, V B

    1980-01-01

    Intense pulsed sources of coherent emission with a continuously tunable wavelength and a high pulse repetition frequency are necessary for atmospheric optics. The use of rhodamine lasing during pumping by a copper dye laser is the most promising. The goals of this work include using the opportunities for improving the lasing properties of dyes pumped by a copper dye laser, choosing dye mixtures that are optimum with respect to their lasing relation, and studying the influence of the dye on their lasing characteristics in order to obtain the optimum energy parameters in the device that is built using a copper vapor laser and an optical attachment. On the basis of an analysis of the equations that describe multiatomic molecular lasing, it is possible to come to a conclusion on the intermolecular processes that determine the lasing effectiveness: singlet-singlet and triplettriplet overabsorption of lasing emission, intercombination (S-T) and internal conversion, and photoconversion in excited electron states. A large probability of emission from the lower singlet state (a large value of the constant of the velocity of radiative decay) is also necessary.

  12. Amplified spontaneous emission of an end-pumped cesium vapor laser

    International Nuclear Information System (INIS)

    An, Guofei; Wang, You; Cai, He; Han, Juhong; Wang, Shunyan; Rong, Kepeng; Yu, Hang; Xue, Liangping; Zhang, Wei; Wang, Hongyuan; Zhou, Jie

    2017-01-01

    Diode pumped alkali lasers (DPALs) provide a significant potential for construction of high-powered lasers. A series of models have been established to analyze the DPAL’s kinetic process and most of them are based on the algorithms in which the amplified spontaneous emission (ASE) effect has not been considered. However, ASE is harmful in realization of a high-powered DPAL since the gain is very high. Usually, ASE becomes serious when the volume of the gain medium is large and the pump power is high. Basically, the conclusions we obtained in this study can be extended to other kinds of laser configurations. (paper)

  13. Imaging the ultrafast Kerr effect, free carrier generation, relaxation and ablation dynamics of Lithium Niobate irradiated with femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Lechuga, Mario, E-mail: mario@io.cfmac.csic.es; Siegel, Jan, E-mail: j.siegel@io.cfmac.csic.es; Hernandez-Rueda, Javier; Solis, Javier [Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid (Spain)

    2014-09-21

    The interaction of high-power single 130 femtosecond (fs) laser pulses with the surface of Lithium Niobate is experimentally investigated in this work. The use of fs-resolution time-resolved microscopy allows us to separately observe the instantaneous optical Kerr effect induced by the pulse and the generation of a free electron plasma. The maximum electron density is reached 550 fs after the peak of the Kerr effect, confirming the presence of a delayed carrier generation mechanism. We have also observed the appearance of transient Newton rings during the ablation process, related to optical interference of the probe beam reflected at the front and back surface of the ablating layer. Finally, we have analyzed the dynamics of the photorefractive effect on a much longer time scale by measuring the evolution of the transmittance of the irradiated area for different fluences below the ablation threshold.

  14. Imaging the ultrafast Kerr effect, free carrier generation, relaxation and ablation dynamics of Lithium Niobate irradiated with femtosecond laser pulses

    International Nuclear Information System (INIS)

    Garcia-Lechuga, Mario; Siegel, Jan; Hernandez-Rueda, Javier; Solis, Javier

    2014-01-01

    The interaction of high-power single 130 femtosecond (fs) laser pulses with the surface of Lithium Niobate is experimentally investigated in this work. The use of fs-resolution time-resolved microscopy allows us to separately observe the instantaneous optical Kerr effect induced by the pulse and the generation of a free electron plasma. The maximum electron density is reached 550 fs after the peak of the Kerr effect, confirming the presence of a delayed carrier generation mechanism. We have also observed the appearance of transient Newton rings during the ablation process, related to optical interference of the probe beam reflected at the front and back surface of the ablating layer. Finally, we have analyzed the dynamics of the photorefractive effect on a much longer time scale by measuring the evolution of the transmittance of the irradiated area for different fluences below the ablation threshold.

  15. Pulse energy dependence of refractive index change in lithium niobium silicate glass during femtosecond laser direct writing.

    Science.gov (United States)

    Cao, Jing; Poumellec, Bertrand; Brisset, François; Lancry, Matthieu

    2018-03-19

    Femtosecond laser-induced refractive index changes in lithium niobium silicate glass were explored at high repetition rate (300 fs, 500 kHz) by polarized light microscopy, full-wave retardation plate, quantitative birefringence microscopy, and digital holographic microscopy. We found three regimes on energy increase. The first one corresponds to isotropic negative refractive index change (for pulse energy ranging 0.4-0.8 μJ/pulse, 0.6 NA, 5μm/s, 650μm focusing depth in the glass). The second one (0.8-1.2 μJ/pulse) corresponds to birefringence with well-defined slow axis orientation. The third one (above 1.2 μJ/pulse) is related to birefringence direction fluctuation. Interestingly, these regimes are consistent with crystallization ones. In addition, an asymmetric orientational writing effect has been detected on birefringence. These topics extend the possibility of controlling refractive index change in multi-component glasses.

  16. Laser Induced Shock Waves and Vaporization in Biological System and Material Science

    National Research Council Canada - National Science Library

    Gerstman, Bernard S

    2008-01-01

    .... We have developed a computational model that allows the calculation of damage resulting from a laser pulse of any duration or energy due to temperature rise, explosive bubble formation, and shock wave production...

  17. Acceleration of Vaporization, Atomization, and Ionization Efficiencies in Inductively Coupled Plasma by Merging Laser-Ablated Particles with Hydrochloric Acid Gas.

    Science.gov (United States)

    Nakazawa, Takashi; Izumo, Saori; Furuta, Naoki

    2016-01-01

    To accelerate the vaporization, atomization, and ionization efficiencies in laser ablation inductively coupled plasma mass spectrometry, we merged HCl gas with laser-ablated particles before introduction into the plasma, to convert their surface constituents from oxides to lower-melting chlorides. When particles were merged with HCl gas generated from a HCl solution at 200°C, the measured concentrations of elements in the particles were 135% higher on average than the concentrations in particles merged with ultrapure water vapor. Particle corrosion and surface roughness were observed by scanning electron microscopy, and oxide conversion to chlorides was confirmed by X-ray photoelectron spectroscopy. Under the optimum conditions, the recoveries of measured elements improved by 23% on average, and the recoveries of elements with high-melting oxides (Sr, Zr, and Th) improved by as much as 36%. These results indicate that vaporization, atomization, and ionization in the ICP improved when HCl gas was merged with the ablated particles.

  18. Laser-assisted electron scattering in strong-field ionization of dense water vapor by ultrashort laser pulses

    International Nuclear Information System (INIS)

    Wilke, M; Al-Obaidi, R; Moguilevski, A; Kothe, A; Engel, N; Metje, J; Kiyan, I Yu; Aziz, E F

    2014-01-01

    We report on strong-field ionization of dense water gas in a short infrared laser pulse. By employing a unique combination of photoelectron spectroscopy with a liquid micro-jet technique, we observe how the character of electron emission at high kinetic energies changes with the increase of the medium density. This change is associated with the process of laser-assisted electron scattering (LAES) on neighboring particles, which becomes a dominant mechanism of hot electron emission at higher medium densities. The manifestation of this mechanism is found to require densities that are orders of magnitude lower than those considered for heating the laser-generated plasmas via the LAES process. The experimental results are supported by simulations of the LAES yield with the use of the Kroll–Watson theory. (paper)

  19. Stagnation of ablated metal vapor in laser fusion reactor with liquid wall

    International Nuclear Information System (INIS)

    Norimatsu, T.; Nagatomo, H.; Azechi, H.; Furukawa, H.; Shimada, Y.; Kurahashi, S.; Kunugi, T.; Kajimura, Y.

    2010-11-01

    In this paper, formation of clusters by ablated materials and those stagnation at the center of a laser fusion reactor with liquid wall are discussed using improved simulation code DECORE. We will report 1) numerical simulation on formation of clusters immediately before the stagnation, 2) preliminary results on the cluster formation at the first bounce of the stagnation, 3) experimental result on the diameter measurement of micro droplets formed in a simulation experiment with back-side irradiation of laser. (author)

  20. Long-Term Outcomes of Laser Prostatectomy for Storage Symptoms: Comparison of Serial 5-Year Followup Data between High Performance System Photoselective Vaporization and Holmium Laser Enucleation of the Prostate.

    Science.gov (United States)

    Cho, Min Chul; Song, Won Hoon; Park, Juhyun; Cho, Sung Yong; Jeong, Hyeon; Oh, Seung-June; Paick, Jae-Seung; Son, Hwancheol

    2018-01-09

    We compared long-term storage symptom outcomes between photoselective laser vaporization of the prostate with a 120 W high performance system and holmium laser enucleation of the prostate. We also determined factors influencing postoperative improvement of storage symptoms in the long term. Included in our study were 266 men, including 165 treated with prostate photoselective laser vaporization using a 120 W high performance system and 101 treated with holmium laser enucleation of the prostate, on whom 60-month followup data were available. Outcomes were assessed serially 6, 12, 24, 36, 48 and 60 months postoperatively using the International Prostate Symptom Score, uroflowmetry and the serum prostate specific antigen level. Postoperative improvement in storage symptoms was defined as a 50% or greater reduction in the subtotal storage symptom score at each followup visit after surgery compared to baseline. Improvements in frequency, urgency, nocturia, subtotal storage symptom scores and the quality of life index were maintained up to 60 months after photoselective laser vaporization or holmium laser enucleation of the prostate. There was no difference in the degree of improvement in storage symptoms or the percent of patients with postoperative improvement in storage symptoms between the 2 groups throughout the long-term followup. However, the holmium laser group showed greater improvement in voiding symptoms and quality of life than the laser vaporization group. On logistic regression analysis a higher baseline subtotal storage symptom score and a higher BOOI (Bladder Outlet Obstruction Index) were the factors influencing the improvement in storage symptoms 5 years after prostate photoselective laser vaporization or holmium laser enucleation. Our serial followup data suggest that storage symptom improvement was maintained throughout the long-term postoperative period for prostate photoselective laser vaporization with a 120 W high performance system and holmium

  1. Raman spectra of lithium compounds

    Science.gov (United States)

    Gorelik, V. S.; Bi, Dongxue; Voinov, Y. P.; Vodchits, A. I.; Gorshunov, B. P.; Yurasov, N. I.; Yurasova, I. I.

    2017-11-01

    The paper is devoted to the results of investigating the spontaneous Raman scattering spectra in the lithium compounds crystals in a wide spectral range by the fibre-optic spectroscopy method. We also present the stimulated Raman scattering spectra in the lithium hydroxide and lithium deuteride crystals obtained with the use of powerful laser source. The symmetry properties of the lithium hydroxide, lithium hydroxide monohydrate and lithium deuteride crystals optical modes were analyzed by means of the irreducible representations of the point symmetry groups. We have established the selection rules in the Raman and infrared absorption spectra of LiOH, LiOH·H2O and LiD crystals.

  2. Progress towards an Autonomous Field Deployable Diode-Laser-Based Differential Absorption Lidar (DIAL for Profiling Water Vapor in the Lower Troposphere

    Directory of Open Access Journals (Sweden)

    Kevin S. Repasky

    2013-11-01

    Full Text Available A laser transmitter has been developed and incorporated into a micro-pulse differential absorption lidar (DIAL for water vapor profiling in the lower troposphere as an important step towards long-term autonomous field operation. The laser transmitter utilizes two distributed Bragg reflector (DBR diode lasers to injection seed a pulsed tapered semiconductor optical amplifier (TSOA, and is capable of producing up to 10 mJ of pulse energy with a 1 ms pulse duration and a 10 kHz pulse repetition frequency. The on-line wavelength of the laser transmitter can operate anywhere along the water vapor absorption feature centered at 828.187 nm (in vacuum depending on the prevailing atmospheric conditions, while the off-line wavelength operates at 828.287 nm. This laser transmitter has been incorporated into a DIAL instrument utilizing a 35.6 cm Schmidt-Cassegrain telescope and fiber coupled avalanche photodiode (APD operating in the photon counting mode. The performance of the DIAL instrument was demonstrated over a ten-day observation period. During this observation period, data from radiosondes were used to retrieve water vapor number density profiles for comparisons with the number density profiles retrieved from the DIAL data.

  3. Continuum and discrete pulsed cavity ring down laser absorption spectra of Br2 vapor.

    Science.gov (United States)

    Sharma, Ramesh C; Huang, Hong-Yi; Chuang, Wang-Ting; Lin, King-Chuen

    2005-07-01

    The absorption cross-sections at room temperature are reported for the first time, of Br2 vapor in overlapping bound-free and bound-bound transition of A(3)pi1u Br2. We obtained discrete absorption cross-section in the rotational structure, the continuum absorption cross-sections, and were also able to measure the absorption cross-section in separate contribution of A(3)pi1u Br2. The absorption cross-sections are increasing with increasing excitation energy in the wavelength region 510-535 nm.

  4. Atomic vapor laser isotope separation at Lawrence Livermore National Laboratory: a status report

    International Nuclear Information System (INIS)

    Davis, J.I.

    1980-01-01

    The field of laser induced chemistry began in earnest early in the 1970's with the initiation of major efforts in laser isotope separation (LIS) of uranium. Though many specialized, small-scale photochemical and diagnostic applications have been identified and evaluated experimentally, and continue to show promise, currently the only high payoff, large-scale applications remain LIS of special elements. Aspects of the physical scaling, technology status and economic basis of uranium LIS are examined with special emphasis on the effort at LLNL

  5. Time-Resolved Quantum Cascade Laser Absorption Spectroscopy of Pulsed Plasma Assisted Chemical Vapor Deposition Processes Containing BCl3

    Science.gov (United States)

    Lang, Norbert; Hempel, Frank; Strämke, Siegfried; Röpcke, Jürgen

    2011-08-01

    In situ measurements are reported giving insight into the plasma chemical conversion of the precursor BCl3 in industrial applications of boriding plasmas. For the online monitoring of its ground state concentration, quantum cascade laser absorption spectroscopy (QCLAS) in the mid-infrared spectral range was applied in a plasma assisted chemical vapor deposition (PACVD) reactor. A compact quantum cascade laser measurement and control system (Q-MACS) was developed to allow a flexible and completely dust-sealed optical coupling to the reactor chamber of an industrial plasma surface modification system. The process under the study was a pulsed DC plasma with periodically injected BCl3 at 200 Pa. A synchronization of the Q-MACS with the process control unit enabled an insight into individual process cycles with a sensitivity of 10-6 cm-1·Hz-1/2. Different fragmentation rates of the precursor were found during an individual process cycle. The detected BCl3 concentrations were in the order of 1014 molecules·cm-3. The reported results of in situ monitoring with QCLAS demonstrate the potential for effective optimization procedures in industrial PACVD processes.

  6. Microstructure and mechanical properties of newly developed aluminum–lithium alloy 2A97 welded by fiber laser

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Banglong [Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials Ministry of Education, Shandong University, Jinan 250061 (China); Qin, Guoliang, E-mail: glqin@sdu.edu.cn [Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials Ministry of Education, Shandong University, Jinan 250061 (China); Meng, Xiangmeng; Ji, Yang; Zou, Yong [Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials Ministry of Education, Shandong University, Jinan 250061 (China); Lei, Zhen [Harbin Welding Institute, Harbin 150028 (China)

    2014-11-03

    The newly developed aluminum–lithium alloy 2A97 was for the first time joined by laser beam welding in order to meet the ever-increased long-term requirements of aerospace, aviation and armament industries. The weld appearance, microstructure, solute segregation, precipitate behavior, and their relationships with mechanical properties of welded joints were investigated. Sound joints with no crack and a few small porosities are obtained under appropriate heat inputs. As a result of heterogeneous nucleation involving the effect of Zr and Li, a non-dendritic equiaxed zone forms between partially melted zone and fusion zone. The crystal morphologies in fusion zone vary from columnar dendrite to equiaxed dendrite, with the increase of constitutional supercooling. Solute segregation leads to the variations of Cu content in grain interior and boundary, as well as the weak ability of re-precipitation of fusion zone. Most precipitates in the base metal dissolve during welding, and fusion zone contains a decreased quantity of δ′, β′, θ′, and T{sub 1}. The ultimate tensile strength of laser welded joints is 83.4% of that of the base metal, and can meet the application requirements from related industries, but the ductility still needs to be improved. Welding defects and loss of solid solution/precipitation hardened structure lead to the degradation of mechanical properties. Tensile fracture occurs in weld with the brittle intergranular dominated mode and premature failure occurs and extends in the equiaxed zone.

  7. Hybrid lasers produced in potassium vapor by off-resonance pumping

    International Nuclear Information System (INIS)

    Clark, B.K.; Stack, C.A.; Muehsler, H.E.

    1993-01-01

    Pulsed amplified emissions are observed at or near atomic transitions cascading down from the K(6S) and K(4D 5/2 ) states, when a pulsed dye laser is tuned near the K(6S left-arrow 4 3/2,1/2 ) and the K(4D 5/2 left-arrow 4P 3/2 ) transitions. Emissions are suppressed when the pulsed dye laser is tuned to the K(4D 3/2 left-arrow 4P 5/3,3/2 ) transitions. The pulsed dye laser is used to excite molecules in a heat-pipe oven from high-bring ro-vibrational levels in the K 2 (X 1 Σ g + ) ground state to ro-vibrational levels in the K 2 (B 1 product u ) state that predissociate to K(4S) and K(4P) atoms. The transitions can be pumped when the laser is tuned sufficiently close to the atomic resonances. We discuss the non-linear mechanisms responsible for the observed emissions. Emissions cascading down from the K(4S) state were first reported by Wang et al

  8. Dual-wavelength green laser with a 4.5 THz frequency difference based on self-frequency- doubling in Nd3+ -doped aperiodically poled lithium niobate.

    Science.gov (United States)

    Maestre, H; Torregrosa, A J; Fernández-Pousa, C R; Rico, M L; Capmany, J

    2008-05-01

    We report a dual-wavelength continuous-wave laser at 542.4 and 546.8 nm based on an Nd(3+)-doped aperiodically poled lithium niobate crystal. Two fundamental infrared (IR) wavelengths at 1084.8 and 1093.6 nm are simultaneously oscillated and self-frequency-doubled to green. The aperiodic domain distribution patterned in the crystal allows for quasi-phase matched self-frequency-doubling of both IR fundamentals while avoiding their sum-frequency mixing.

  9. Comparative study of diode-pumped alkali vapor laser and exciplex-pumped alkali laser systems and selection principal of parameters

    Science.gov (United States)

    Huang, Wei; Tan, Rongqing; Li, Zhiyong; Han, Gaoce; Li, Hui

    2017-03-01

    A theoretical model based on common pump structure is proposed to analyze the output characteristics of a diode-pumped alkali vapor laser (DPAL) and XPAL (exciplex-pumped alkali laser). Cs-DPAL and Cs-Ar XPAL systems are used as examples. The model predicts that an optical-to-optical efficiency approaching 80% can be achieved for continuous-wave four- and five-level XPAL systems with broadband pumping, which is several times the pumped linewidth for DPAL. Operation parameters including pumped intensity, temperature, cell's length, mixed gas concentration, pumped linewidth, and output coupler are analyzed for DPAL and XPAL systems based on the kinetic model. In addition, the predictions of selection principal of temperature and cell's length are also presented. The concept of the equivalent "alkali areal density" is proposed. The result shows that the output characteristics with the same alkali areal density but different temperatures turn out to be equal for either the DPAL or the XPAL system. It is the areal density that reflects the potential of DPAL or XPAL systems directly. A more detailed analysis of similar influences of cavity parameters with the same areal density is also presented.

  10. Conceptual design study of the hylife lithium fall laser fusion chamber. FY 1979 annual report

    International Nuclear Information System (INIS)

    1979-01-01

    In FY 1979, the basic configuration of FY 1978 was used as a reference point. Many studies were then made to either generate more design information concerning this design or to produce new concepts that would lead to a superior configuration. Among these activities were a detailed weight analysis, an assembly sequence, a chamber vibration analysis, a splash baffle stress study, and an analysis of first wall thermal stresses. Then some new concepts were introduced that pertained to the first wall, the lithium inlet nozzle, the chamber supports, the inlet piping, and pressure vessel

  11. IR Laser-Induced Process for Chemical Vapor Deposition of Polyselenocarbosilane Films

    Czech Academy of Sciences Publication Activity Database

    Santos, M.; Diaz, L.; Urbanová, Markéta; Pokorná, Dana; Bastl, Zdeněk; Šubrt, Jan; Pola, Josef

    2006-01-01

    Roč. 76, 1-2 (2006), s. 178-185 ISSN 0165-2370 R&D Projects: GA MŠk(CZ) ME 684 Grant - others:MCyT(ES) BQU2003/08531/CO2/02 Institutional research plan: CEZ:AV0Z40720504; CEZ:AV0Z40400503; CEZ:AV0Z40320502 Keywords : polyselenocarbosilane * selenium * laser decomposition Subject RIV: CH - Nuclear ; Quantum Chemistry Impact factor: 1.412, year: 2006

  12. Graphene synthesis by laser-assisted chemical vapor deposition on Ni plate and the effect of process parameters on uniform graphene growth

    International Nuclear Information System (INIS)

    Jiang, Juan; Lin, Zhe; Ye, Xiaohui; Zhong, Minlin; Huang, Ting; Zhu, Hongwei

    2014-01-01

    A fast, simple technique was developed to fabricate few-layer graphene films at ambient pressure and room temperature by laser-assisted chemical vapor deposition on polycrystalline Ni plates. Laser scanning speed was found as the most important factor in the production of few-layer graphene. The quality of graphene films was controlled by varying the laser power. Uniform graphene ribbons with a width of 1.5 mm and a length of 16 mm were obtained at a scanning speed of 1.3 mm/s and a laser power of 600 W. The developed technique provided a promising application of a high-power laser system to fabricate a graphene film. - Highlights: • Uniform few-layer graphene was fabricated at room temperature and ambient conditions. • Laser-assisted chemical vapor deposition was used to grow the layers in a few seconds. • The effect of process parameters on graphene growth was discussed. • This cost effective method could facilitate the integration of graphene in electronic devices

  13. Laser transurethral resection of the prostate: Safety study of a novel system of photoselective vaporization with high power diode laser in prostates larger than 80mL.

    Science.gov (United States)

    Andrés, G; Arance, I; Gimbernat, H; Redondo, C; García-Tello, A; Angulo, J C

    2015-01-01

    To present the feasibility of photoselective vaporization of the prostate (PVP) with of a new diode laser-resection system. Surgical treatment of benign prostatic hyperplasia (BPH) is constantly evolving. Laser techniques are increasingly used in prostates of large size. A prospective study was performed to evaluate operative data and patient outcomes with PVP using high-power diode laser (HPD) and a novel quartz-head fiber with shovel shape in patients with prostate>80mL. Demographic data, operative time, hemoglobin loss, operative results (IPSS, quality of life (QoL), Qmax, post void residue (PVR), IIEF-5 and micturition diary) and complications following Clavien-Dindo classification are described. Thirty-one patients were included in the study. Sixteen (51.6%) were on active antiplatelet treatment and 12 (38.7%) had received anticoagulants before surgery. All cases were followed at least 6mo. No intraoperative or postoperative major complications occurred. Three patients (9.7%) had minor complications according to Clavien-Dindo classification. Twenty-seven (87.1%) were discharged on postoperative day one without catheter. There were significant improvements in IPSS, QoL, Qmax and PVR, both at 3 and 6mo (Plaser-resection is a safe procedure, achieving excellent results in terms of IPSS, QoL and Qmax in large prostates even in high-risk patients. Longer follow-up, comparative and randomized controlled studies are needed to widespread these results. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Lithium batteries, anodes, and methods of anode fabrication

    KAUST Repository

    Li, Lain-Jong; Wu, Feng-Yu; Kumar, Pushpendra; Ming, Jun

    2016-01-01

    Prelithiation of a battery anode carried out using controlled lithium metal vapor deposition. Lithium metal can be avoided in the final battery. This prelithiated electrode is used as potential anode for Li- ion or high energy Li-S battery

  15. Plasma production during vaporization of materials by the radiation from a CO2 TEA laser

    International Nuclear Information System (INIS)

    Gaponov, S.V.; Strikovskii, M.D.

    1982-01-01

    The energy and space and time dependence are investigated for a laser flare. Two qualitatively different regimes are discovered for the ejection of the plasma, where the transition between them has a threshold character (in the radiation flux density). The measured dependence of the threshold on the atomic number of the target element has a form which is indicative of a connection between the dynamics of the flare formation and the electronic structure of the atom. A model is proposed for interpreting this effect

  16. Growth dynamics of carbon-metal particles and nanotubes synthesized by CO2 laser vaporization

    Science.gov (United States)

    Kokai, F.; Takahashi, K.; Yudasaka, M.; Iijima, S.

    To study the growth of carbon-Co/Ni particles and single-wall carbon nanotubes (SWNTs) by 20 ms CO2 laser-pulse irradiation of a graphite-Co/Ni (1.2 at.%) target in an Ar gas atmosphere (600 Torr), we used emission imaging spectroscopy and shadowgraphy with a temporal resolution of 1.67 ms. Wavelength-selected emission images showed that C2 emission was strong in the region close to the target (within 2 cm), while for the same region the blackbody radiation from the large clusters or particles increased with increasing distance from the target. Shadowgraph images showed that the viscous flow of carbon and metal species formed a mushroom or a turbulent cloud spreading slowly into the Ar atmosphere, indicating that particles and SWNTs continued to grow as the ejected material cooled. In addition, emission imaging spectroscopy at 1200 °C showed that C2 and hot clusters and particles with higher emission intensities were distributed over much wider areas. We discuss the growth dynamics of the particles and SWNTs through the interaction of the ambient Ar with the carbon and metal species released from the target by the laser pulse.

  17. Hydrogen isotope correction for laser instrument measurement bias at low water vapor concentration using conventional isotope analyses: application to measurements from Mauna Loa Observatory, Hawaii.

    Science.gov (United States)

    Johnson, L R; Sharp, Z D; Galewsky, J; Strong, M; Van Pelt, A D; Dong, F; Noone, D

    2011-03-15

    The hydrogen and oxygen isotope ratios of water vapor can be measured with commercially available laser spectroscopy analyzers in real time. Operation of the laser systems in relatively dry air is difficult because measurements are non-linear as a function of humidity at low water concentrations. Here we use field-based sampling coupled with traditional mass spectrometry techniques for assessing linearity and calibrating laser spectroscopy systems at low water vapor concentrations. Air samples are collected in an evacuated 2 L glass flask and the water is separated from the non-condensable gases cryogenically. Approximately 2 µL of water are reduced to H(2) gas and measured on an isotope ratio mass spectrometer. In a field experiment at the Mauna Loa Observatory (MLO), we ran Picarro and Los Gatos Research (LGR) laser analyzers for a period of 25 days in addition to periodic sample collection in evacuated flasks. When the two laser systems are corrected to the flask data, they are strongly coincident over the entire 25 days. The δ(2)H values were found to change by over 200‰ over 2.5 min as the boundary layer elevation changed relative to MLO. The δ(2)H values ranged from -106 to -332‰, and the δ(18)O values (uncorrected) ranged from -12 to -50‰. Raw data from laser analyzers in environments with low water vapor concentrations can be normalized to the international V-SMOW scale by calibration to the flask data measured conventionally. Bias correction is especially critical for the accurate determination of deuterium excess in dry air. Copyright © 2011 John Wiley & Sons, Ltd.

  18. Holographic recording in a doubly doped lithium niobate crystal with two wavelengths: a blue laser diode and a green laser

    Science.gov (United States)

    Komori, Yuichi; Ishii, Yukihiro

    2010-08-01

    A doubly-doped LiNbO3 (LN) crystal has been well used as a nonvolatile two-wavelength recording material. By using two levels of the crystal, two-kind holograms can be recorded on one crystal; a hologram is recorded with a 405-nm blue laser diode (LD) for a deep Mn level, and another hologram is with a 532-nm green laser for a shallow Fe level. The recording capacity doubles. A 780-nm LD is non-volatile reconstructing source since the LD line is insensitive to both levels. Multiplexed reconstructed images are demonstrated by using a sharp angular selectivity of a volume LN crystal keeping Bragg condition with spherical reconstructions.

  19. Lithium niobate bulk crystallization promoted by CO{sub 2} laser radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, N.M., E-mail: nmferreira@ua.pt [i3N - Aveiro, Physics Department, Aveiro University, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Costa, F.M. [i3N - Aveiro, Physics Department, Aveiro University, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal); Nogueira, R.N. [Instituto de Telecomunicacoes, 3810-193 Aveiro (Portugal); Graca, M.P.F. [i3N - Aveiro, Physics Department, Aveiro University, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Crystallization of LiNbO{sub 3} nanocrystals in a SiO{sub 2} matrix by CO{sub 2} laser irradiation process. Black-Right-Pointing-Pointer Samples heat-treated at 650 Degree-Sign C (4 h) and laser treated (4 W/500 s) show similar morphology. Black-Right-Pointing-Pointer Glass-ceramics produced by laser process requires a very low processing time. - Abstract: The crystallization induced by laser radiation is a very promising technique to promote glass/ceramic transformation, being already used to produce crystalline patterns on glass surfaces. In this work, a SiO{sub 2}-Li{sub 2}O-Nb{sub 2}O{sub 5} glass, prepared by the sol-gel route, was submitted to CO{sub 2} laser radiation and conventional heat-treatments in order to induce the LiNbO{sub 3} crystallization. The structure and morphology of the samples prepared by both routes was analyzed as a function of exposure time, radiation power and heat-treatment temperatures by XRD, Raman spectroscopy and SEM. The results reveal a correlation between the crystallization degree of LiNbO{sub 3} particles and glass matrix with the heat treatment type and experimental parameters. An heat-treatment at 650 Degree-Sign C/4 h was necessary to induce crystallization in heat treatments samples while 4 W/500 s was enough for laser radiation ones, corresponding a reduction time processing of {approx}14 000 s.

  20. Cascaded quadratic soliton compression of high-power femtosecond fiber lasers in Lithium Niobate crystals

    DEFF Research Database (Denmark)

    Bache, Morten; Moses, Jeffrey; Wise, Frank W.

    2008-01-01

    The output of a high-power femtosecond fiber laser is typically 300 fs with a wavelength around $\\lambda=1030-1060$ nm. Our numerical simulations show that cascaded quadratic soliton compression in bulk LiNbO$_3$ can compress such pulses to below 100 fs.......The output of a high-power femtosecond fiber laser is typically 300 fs with a wavelength around $\\lambda=1030-1060$ nm. Our numerical simulations show that cascaded quadratic soliton compression in bulk LiNbO$_3$ can compress such pulses to below 100 fs....

  1. Study of the ionization of sodium vapor in the presence of resonant laser radiation

    International Nuclear Information System (INIS)

    Carre, B.

    1986-06-01

    Ionization of a diffuse sodium jet, excited by laser radiation (D2 resonance), either continuous or pulsed, is studied by electron spectroscopy. Results show: associative ionization (AI) in the collision of two Na(3p) excited atoms; occupancy of highly excited nl states in energy association collisions of two Na(3p) followed by Penning collisional ionization (CI) in the system Na(nl) + Na(3p); heating of electrons by 1, 2, or 3 superelastic collisions with Na(3p). For both the excitation cases (continuous or pulsed source) analysis of experiment results leads to a description of the whole of the ionized medium, characterized as being low density and the site of the ambipolar diffusion of charged particles. A highly simplified model describes the kinetic and electrokinetic equilibrium (continuous case) in which the different populations of distinct nonthermalized energy (low energy primary electrons, hot electrons) play specific roles. The cross sections associated with AI and CI are estimated from experiment results using the model [fr

  2. Compositional depth profiles of the type 316 stainless steel undergone the corrosion in liquid lithium using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Li, Ying; Ke, Chuan; Liu, Xiang; Gou, Fujun; Duan, Xuru; Zhao, Yong

    2017-12-01

    Liquid metal lithium cause severe corrosion on the surface of metal structure material that used in the blanket and first wall of fusion device. Fast and accurate compositional depth profile measurement for the boundary layer of the corroded specimen will reveal the clues for the understanding and evaluation of the liquid lithium corrosion process as well as the involved corrosion mechanism. In this work, the feasibility of laser-induced breakdown spectroscopy for the compositional depth profile analysis of type 316 stainless steel which was corroded by liquid lithium in certain conditions was demonstrated. High sensitivity of LIBS was revealed especially for the corrosion medium Li in addition to the matrix elements of Fe, Cr, Ni and Mn by the spectral analysis of the plasma emission. Compositional depth profile analysis for the concerned elements which related to corrosion was carried out on the surface of the corroded specimen. Based on the verified local thermodynamic equilibrium shot-by-shot along the depth profile, the matrix effect was evaluated as negligible by the extracted physical parameter of the plasmas generated by each laser pulse in the longitudinal depth profile. In addition, the emission line intensity ratios were introduced to further reduce the impact on the emission line intensity variations arise from the strong inhomogeneities on the corroded surface. Compositional depth profiles for the matrix elements of Fe, Cr, Ni, Mn and the corrosion medium Li were constructed with their measured relative emission line intensities. The distribution and correlations of the concerned elements in depth profile may indicate the clues to the complicated process of composition diffusion and mass transfer. The results obtained demonstrate the potentiality of LIBS as an effective technique to perform spectrochemical measurement in the research fields of liquid metal lithium corrosion.

  3. Evolution of elastic x-ray scattering in laser-shocked warm dense lithium.

    Science.gov (United States)

    Kugland, N L; Gregori, G; Bandyopadhyay, S; Brenner, C M; Brown, C R D; Constantin, C; Glenzer, S H; Khattak, F Y; Kritcher, A L; Niemann, C; Otten, A; Pasley, J; Pelka, A; Roth, M; Spindloe, C; Riley, D

    2009-12-01

    We have studied the dynamics of warm dense Li with near-elastic x-ray scattering. Li foils were heated and compressed using shock waves driven by 4-ns-long laser pulses. Separate 1-ns-long laser pulses were used to generate a bright source of 2.96 keV Cl Ly- alpha photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120 degrees using a highly oriented pyrolytic graphite crystal operated in the von Hamos geometry. A variable delay between the heater and backlighter laser beams measured the scattering time evolution. Comparison with radiation-hydrodynamics simulations shows that the plasma is highly coupled during the first several nanoseconds, then relaxes to a moderate coupling state at later times. Near-elastic scattering amplitudes have been successfully simulated using the screened one-component plasma model. Our main finding is that the near-elastic scattering amplitudes are quite sensitive to the mean ionization state Z[over ] and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.

  4. Evolution of elastic x-ray scattering in laser-shocked warm dense lithium

    International Nuclear Information System (INIS)

    Kugland, N. L.; Niemann, C.; Gregori, G.; Bandyopadhyay, S.; Spindloe, C.; Brenner, C. M.; Brown, C. R. D.; Constantin, C.; Glenzer, S. H.; Khattak, F. Y.; Kritcher, A. L.; Otten, A.; Pelka, A.; Roth, M.; Pasley, J.; Riley, D.

    2009-01-01

    We have studied the dynamics of warm dense Li with near-elastic x-ray scattering. Li foils were heated and compressed using shock waves driven by 4-ns-long laser pulses. Separate 1-ns-long laser pulses were used to generate a bright source of 2.96 keV Cl Ly-α photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120 deg. using a highly oriented pyrolytic graphite crystal operated in the von Hamos geometry. A variable delay between the heater and backlighter laser beams measured the scattering time evolution. Comparison with radiation-hydrodynamics simulations shows that the plasma is highly coupled during the first several nanoseconds, then relaxes to a moderate coupling state at later times. Near-elastic scattering amplitudes have been successfully simulated using the screened one-component plasma model. Our main finding is that the near-elastic scattering amplitudes are quite sensitive to the mean ionization state Z and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.

  5. Experimental lithium system. Final report

    International Nuclear Information System (INIS)

    Kolowith, R.; Berg, J.D.; Miller, W.C.

    1985-04-01

    A full-scale mockup of the Fusion Materials Irradiation Test (FMIT) Facility lithium system was built at the Hanford Engineering Development Laboratory (HEDL). This isothermal mockup, called the Experimental Lithium System (ELS), was prototypic of FMIT, excluding the accelerator and dump heat exchanger. This 3.8 m 3 lithium test loop achieved over 16,000 hours of safe and reliable operation. An extensive test program demonstrated satisfactory performance of the system components, including the HEDL-supplied electromagnetic lithium pump, the lithium jet target, the purification and characterization hardware, as well as the auxiliary argon and vacuum systems. Experience with the test loop provided important information on system operation, performance, and reliability. This report presents a complete overview of the entire Experimental Lithium System test program and also includes a summary of such areas as instrumentation, coolant chemistry, vapor/aerosol transport, and corrosion

  6. Fabrication of 100 A class, 1 m long coated conductor tapes by metal organic chemical vapor deposition and pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Selvamanickam, V.; Lee, H.G.; Li, Y.; Xiong, X.; Qiao, Y.; Reeves, J.; Xie, Y.; Knoll, A.; Lenseth, K

    2003-10-15

    SuperPower has been scaling up YBa{sub 2}Cu{sub 3}O{sub x}-based second-generation superconducting tapes by techniques such as pulsed laser deposition (PLD) using industrial laser and metal organic chemical vapor deposition (MOCVD). Both techniques offer advantage of high deposition rates, which is important for high throughput. Using highly-polished substrates produced in a reel-to-reel polishing facility and buffer layers deposited in a pilot ion beam assisted deposition facility, meter-long second-generation high temperature superconductor tapes have been produced. 100 A class, meter-long coated conductor tapes have been reproducibly demonstrated in this work by both MOCVD and PLD. The best results to date are 148 A over 1.06 m by MOCVD and 135 A over 1.1 m by PLD using industrial laser.

  7. Laser cutting of graphite anodes for automotive lithium-ion secondary batteries: investigations in the edge geometry and heat-affected zone

    Science.gov (United States)

    Schmieder, Benjamin

    2012-03-01

    To serve the high need of lithium-ion secondary batteries of the automobile industry in the next ten years it is necessary to establish highly reliable, fast and non abrasive machining processes. In previous works [1] it was shown that high cutting speeds with several meters per second are achievable. For this, mainly high power single mode fibre lasers with up to several kilo watts were used. Since lithium-ion batteries are very fragile electro chemical systems, the cutting speed is not the only thing important. To guarantee a high cycling stability and a long calendrical life time the edge quality and the heat affected zone (HAZ) are equally important. Therefore, this paper tries to establish an analytical model for the geometry of the cutting edge based on the ablation thresholds of the different materials. It also deals with the composition of the HAZ in dependence of the pulse length, generated by laser remote cutting with pulsed fibre laser. The characterisation of the HAZ was done by optical microscopy, SEM, EDX and Raman microscopy.

  8. Near-field imaging of femtosecond laser ablated sub-λ/4 holes in lithium niobate

    International Nuclear Information System (INIS)

    Rodenas, Airan; Lamela, Jorge; Jaque, Daniel; Lifante, Gines; Jaque, Francisco; Garcia-Martin, Antonio; Zhou Guangyong; Gu Min

    2009-01-01

    We report on the direct femtosecond laser ablation of sub-λ/4 (80-250 nm) holes in LiNbO 3 crystals and on its local near-field imaging. We show that the near-field transmission of holes can feature an attenuation of ∼75% at hole central position, and a ∼20% transmission enhancement at its sides. This high-contrast ring-shaped near-field distribution is found to be in agreement with simulations, suggesting the surface relief as the main contrast mechanism.

  9. High-strength laser welding of aluminum-lithium scandium-doped alloys

    Science.gov (United States)

    Malikov, A. G.; Ivanova, M. Yu.

    2016-11-01

    The work presents the experimental investigation of laser welding of an aluminum alloy (system Al-Mg-Li) and aluminum alloy (system Al-Cu-Li) doped with Sc. The influence of nano-structuring of the surface layer welded joint by cold plastic deformation on the strength properties of the welded joint is determined. It is founded that, regarding the deformation degree over the thickness, the varying value of the welded joint strength is different for these aluminum alloys. The strength of the plastically deformed welded joint, aluminum alloys of the Al-Mg-Li and Al-Cu-Li systems reached 0.95 and 0.6 of the base alloy strength, respectively.

  10. Predicting the heat of vaporization of iron at high temperatures using time-resolved laser-induced incandescence and Bayesian model selection

    Science.gov (United States)

    Sipkens, Timothy A.; Hadwin, Paul J.; Grauer, Samuel J.; Daun, Kyle J.

    2018-03-01

    Competing theories have been proposed to account for how the latent heat of vaporization of liquid iron varies with temperature, but experimental confirmation remains elusive, particularly at high temperatures. We propose time-resolved laser-induced incandescence measurements on iron nanoparticles combined with Bayesian model plausibility, as a novel method for evaluating these relationships. Our approach scores the explanatory power of candidate models, accounting for parameter uncertainty, model complexity, measurement noise, and goodness-of-fit. The approach is first validated with simulated data and then applied to experimental data for iron nanoparticles in argon. Our results justify the use of Román's equation to account for the temperature dependence of the latent heat of vaporization of liquid iron.

  11. Selection of the optimal combination of water vapor absorption lines for detection of temperature in combustion zones of mixing supersonic gas flows by diode laser absorption spectrometry

    International Nuclear Information System (INIS)

    Mironenko, V.R.; Kuritsyn, Yu.A.; Bolshov, M.A.; Liger, V.V.

    2017-01-01

    Determination of a gas medium temperature by diode laser absorption spectrometry (DLAS) is based on the measurement of integral intensities of the absorption lines of a test molecule (generally water vapor molecule). In case of local thermodynamic equilibrium temperature is inferred from the ratio of the integral intensities of two lines with different low energy levels. For the total gas pressure above 1 atm the absorption lines are broadened and one cannot find isolated well resolved water vapor absorption lines within relatively narrow spectral interval of fast diode laser (DL) tuning range (about 3 cm"−"1). For diagnostics of a gas object in the case of high temperature and pressure DLAS technique can be realized with two diode lasers working in different spectral regions with strong absorption lines. In such situation the criteria of the optimal line selection differs significantly from the case of narrow lines. These criteria are discussed in our work. The software for selection the optimal spectral regions using the HITRAN-2012 and HITEMP data bases is developed. The program selects spectral regions of DL tuning, minimizing the error of temperature determination δT/T, basing on the attainable experimental error of line intensity measurement δS. Two combinations of optimal spectral regions were selected – (1.392 & 1.343 μm) and (1.392 & 1.339 μm). Different algorithms of experimental data processing are discussed.

  12. Influence of scandium on the microstructure and strength properties of the welded joint at the laser welding of aluminum-lithium alloys

    Science.gov (United States)

    Malikov, A. G.; Golyshev, A. A.; Ivanova, M. Yu.

    2017-10-01

    Today, aeronautical equipment manufacture involves up-to-date high-strength aluminum alloys of decreased density resulting from lithium admixture. Various technologies of fusible welding of these alloys are being developed. Serious demands are imposed to the welded joints of aluminum alloys in respect to their strength characteristics. The paper presents experimental investigations of the optimization of the laser welding of aluminum alloys with the scandium-modified welded joint. The effect of scandium on the micro-and macro-structure has been studied as well as the strength characteristics of the welded joint. It has been found that scandium under in the laser welding process increases the welded joint elasticity for the system Al-Mg-Li, aluminum alloy 1420 by 20 %, and almost doubles the same for the system Al-Cu-Li, aluminum alloy 1441.

  13. The structure and composition of lithium fluoride films grown by off-axis pulsed laser ablation

    International Nuclear Information System (INIS)

    Henley, S.J.; Ashfold, M.N.R.; Pearce, S.R.J.

    2003-01-01

    Alkali halide coatings have been reported to act as effective dipole layers to lower the surface work function and induce a negative electron affinity of diamond surfaces. Here, the results of the analysis of films grown on silicon and quartz substrates by 193 nm pulsed laser ablation from a commercially available sintered disk of LiF are reported. The morphology, composition and crystallinity of films grown are examined and suitable deposition parameters for optimising the growth are suggested. The ablation was shown to be very efficient at removing a large amount of material from the target, even at relatively low fluence. The morphology of the films produced was poor, however, with a high density of asperities categorised as either particulates produced by exfoliation, or as droplets produced by hydrodynamic sputtering. An improved morphology with smaller droplets and fewer particulates could be produced by mounting the substrate at an angle of 65 deg. to the axis of the ablation plume and using a fluence close to the measured ablation threshold of 1.2±0.1 J/cm 2 . The elemental composition of the films was shown to be indistinguishable from that of bulk LiF, despite evidence for significant recondensation of Li back onto the target. Films containing crystal grains oriented with the direction normal to the substrate surface were observed at substrate temperatures in excess of 300 deg. C. An improved extent of orientation was observed on the quartz substrates

  14. Infrared 7.6-microm lead-salt diode laser heterodyne radiometry of water vapor in a CH4-air premixed flat flame.

    Science.gov (United States)

    Weidmann, Damien; Courtois, Daniel

    2003-02-20

    We deal with the design of a diode laser heterodyne radiometer and its application in a combustion process. We present some experimental results obtained with a CH4-air premised flat flame as the optical source. The goal is to prove that heterodyne detection techniques are relevant in remote detection and diagnostics of combustion and can have important applications in both civil and military fields. To the best of our knowledge, it is the first time that this demonstration is made. The radiometer, in spite of the low-power lead-salt diode laser used as a local oscillator, enables us to record high-temperature water-vapor emission spectra in the region of 1315 cm(-1).

  15. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Marmer, G.J.; Dunn, C.P.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Yuen, C.R.; Cleland, J.H. (ed.)

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs.

  16. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    International Nuclear Information System (INIS)

    Marmer, G.J.; Dunn, C.P.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Yuen, C.R.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs

  17. Accurate Laser Measurements of the Water Vapor Self-Continuum Absorption in Four Near Infrared Atmospheric Windows. a Test of the MT_CKD Model.

    Science.gov (United States)

    Campargue, Alain; Kassi, Samir; Mondelain, Didier; Romanini, Daniele; Lechevallier, Loïc; Vasilchenko, Semyon

    2017-06-01

    The semi empirical MT_CKD model of the absorption continuum of water vapor is widely used in atmospheric radiative transfer codes of the atmosphere of Earth and exoplanets but lacks of experimental validation in the atmospheric windows. Recent laboratory measurements by Fourier transform Spectroscopy have led to self-continuum cross-sections much larger than the MT_CKD values in the near infrared transparency windows. In the present work, we report on accurate water vapor absorption continuum measurements by Cavity Ring Down Spectroscopy (CRDS) and Optical-Feedback-Cavity Enhanced Laser Spectroscopy (OF-CEAS) at selected spectral points of the transparency windows centered around 4.0, 2.1 and 1.25 μm. The temperature dependence of the absorption continuum at 4.38 μm and 3.32 μm is measured in the 23-39 °C range. The self-continuum water vapor absorption is derived either from the baseline variation of spectra recorded for a series of pressure values over a small spectral interval or from baseline monitoring at fixed laser frequency, during pressure ramps. In order to avoid possible bias approaching the water saturation pressure, the maximum pressure value was limited to about 16 Torr, corresponding to a 75% humidity rate. After subtraction of the local water monomer lines contribution, self-continuum cross-sections, C_{S}, were determined with a few % accuracy from the pressure squared dependence of the spectra base line level. Together with our previous CRDS and OF-CEAS measurements in the 2.1 and 1.6 μm windows, the derived water vapor self-continuum provides a unique set of water vapor self-continuum cross-sections for a test of the MT_CKD model in four transparency windows. Although showing some important deviations of the absolute values (up to a factor of 4 at the center of the 2.1 μm window), our accurate measurements validate the overall frequency dependence of the MT_CKD2.8 model.

  18. Pulsed hybrid dual wavelength Y-branch-DFB laser-tapered amplifier system suitable for water vapor detection at 965 nm with 16 W peak power

    Science.gov (United States)

    Vu, Thi N.; Klehr, Andreas; Sumpf, Bernd; Hoffmann, Thomas; Liero, Armin; Tränkle, Günther

    2016-03-01

    A master oscillator power amplifier system emitting alternatingly at two neighbored wavelengths around 965 nm is presented. As master oscillator (MO) a Y-branch DFB-laser is used. The two branches, which can be individually controlled, deliver the two wavelengths needed for a differential absorption measurement of water vapor. Adjusting the current through the DFB sections, the wavelength can be adjusted with respect to the targeted either "on" or "off" resonance, respectively wavelength λon or wavelength λoff. The emission of this laser is amplified in a tapered amplifier (TA). The ridge waveguide section of the TA acts as optical gate to generate short pulses with duration of 8 ns at a repetition rate of 25 kHz, the flared section is used for further amplification to reach peak powers up to 16 W suitable for micro-LIDAR (Light Detection and Ranging). The necessary pulse current supply user a GaN-transistor based driver electronics placed close to the power amplifier (PA). The spectral properties of the emission of the MO are preserved by the PA. A spectral line width smaller than 10 pm and a side mode suppression ratio (SMSR) of 37 dB are measured. These values meet the demands for water vapor absorption measurements under atmospheric conditions.

  19. Performance Improvement of Microcrystalline p-SiC/i-Si/n-Si Thin Film Solar Cells by Using Laser-Assisted Plasma Enhanced Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    Hsin-Ying Lee

    2014-01-01

    Full Text Available The microcrystalline p-SiC/i-Si/n-Si thin film solar cells treated with hydrogen plasma were fabricated at low temperature using a CO2 laser-assisted plasma enhanced chemical vapor deposition (LAPECVD system. According to the micro-Raman results, the i-Si films shifted from 482 cm−1 to 512 cm−1 as the assisting laser power increased from 0 W to 80 W, which indicated a gradual transformation from amorphous to crystalline Si. From X-ray diffraction (XRD results, the microcrystalline i-Si films with (111, (220, and (311 diffraction were obtained. Compared with the Si-based thin film solar cells deposited without laser assistance, the short-circuit current density and the power conversion efficiency of the solar cells with assisting laser power of 80 W were improved from 14.38 mA/cm2 to 18.16 mA/cm2 and from 6.89% to 8.58%, respectively.

  20. High throughput production of nanocomposite SiO x powders by plasma spray physical vapor deposition for negative electrode of lithium ion batteries

    Directory of Open Access Journals (Sweden)

    Keiichiro Homma

    2014-04-01

    Full Text Available Nanocomposite Si/SiO x powders were produced by plasma spray physical vapor deposition (PS-PVD at a material throughput of 480 g h−1. The powders are fundamentally an aggregate of primary ~20 nm particles, which are composed of a crystalline Si core and SiO x shell structure. This is made possible by complete evaporation of raw SiO powders and subsequent rapid condensation of high temperature SiO x vapors, followed by disproportionation reaction of nucleated SiO x nanoparticles. When CH4 was additionally introduced to the PS-PVD, the volume of the core Si increases while reducing potentially the SiO x shell thickness as a result of the enhanced SiO reduction, although an unfavorable SiC phase emerges when the C/Si molar ratio is greater than 1. As a result of the increased amount of Si active material and reduced source for irreversible capacity, half-cell batteries made of PS-PVD powders with C/Si = 0.25 have exhibited improved initial efficiency and maintenance of capacity as high as 1000 mAh g−1 after 100 cycles at the same time.

  1. High throughput production of nanocomposite SiO x powders by plasma spray physical vapor deposition for negative electrode of lithium ion batteries.

    Science.gov (United States)

    Homma, Keiichiro; Kambara, Makoto; Yoshida, Toyonobu

    2014-04-01

    Nanocomposite Si/SiO x powders were produced by plasma spray physical vapor deposition (PS-PVD) at a material throughput of 480 g h -1 . The powders are fundamentally an aggregate of primary ∼20 nm particles, which are composed of a crystalline Si core and SiO x shell structure. This is made possible by complete evaporation of raw SiO powders and subsequent rapid condensation of high temperature SiO x vapors, followed by disproportionation reaction of nucleated SiO x nanoparticles. When CH 4 was additionally introduced to the PS-PVD, the volume of the core Si increases while reducing potentially the SiO x shell thickness as a result of the enhanced SiO reduction, although an unfavorable SiC phase emerges when the C/Si molar ratio is greater than 1. As a result of the increased amount of Si active material and reduced source for irreversible capacity, half-cell batteries made of PS-PVD powders with C/Si = 0.25 have exhibited improved initial efficiency and maintenance of capacity as high as 1000 mAh g -1 after 100 cycles at the same time.

  2. Laser induced explosive vapor and cavitation resulting in effective irrigation of the root canal. Part 1: a visualization study

    NARCIS (Netherlands)

    Blanken, J.; de Moor, R.J.G.; Meire, M.; Verdaasdonk, R.

    2009-01-01

    Background and Objectives: Limited information exists regarding the induction of explosive vapor and cavitation bubbles in an endodontic rinsing solution. It is also not clear whether a fiber has to be moved in the irrigation solution or can be kept stationary. No information is available on safe

  3. Laser Induced Explosive Vapor and Cavitation Resulting in Effective Irrigation of the Root Canal. Part 1 : A Visualization Study

    NARCIS (Netherlands)

    Blanken, Jan; De Moor, Roeland Jozef Gentil; Meire, Maarten; Verdaasdonk, Rudolf

    Background and Objectives: Limited information exists regarding the induction of explosive vapor and cavitation bubbles in an endodontic rinsing solution. It is also not clear whether a fiber has to be moved in the irrigation solution or can be kept stationary. No information is available on safe

  4. High-speed assembly language (80386/80387) programming for laser spectra scan control and data acquisition providing improved resolution water vapor spectroscopy

    Science.gov (United States)

    Allen, Robert J.

    1988-01-01

    An assembly language program using the Intel 80386 CPU and 80387 math co-processor chips was written to increase the speed of data gathering and processing, and provide control of a scanning CW ring dye laser system. This laser system is used in high resolution (better than 0.001 cm-1) water vapor spectroscopy experiments. Laser beam power is sensed at the input and output of white cells and the output of a Fabry-Perot. The assembly language subroutine is called from Basic, acquires the data and performs various calculations at rates greater than 150 faster than could be performed by the higher level language. The width of output control pulses generated in assembly language are 3 to 4 microsecs as compared to 2 to 3.7 millisecs for those generated in Basic (about 500 to 1000 times faster). Included are a block diagram and brief description of the spectroscopy experiment, a flow diagram of the Basic and assembly language programs, listing of the programs, scope photographs of the computer generated 5-volt pulses used for control and timing analysis, and representative water spectrum curves obtained using these programs.

  5. Use of p- and n-type vapor phase doping and sub-melt laser anneal for extension junctions in sub-32 nm CMOS technology

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, N.D., E-mail: Duy.Nguyen@imec.b [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Rosseel, E. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Takeuchi, S. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Department of Physics and Astronomy, KU Leuven, B-3001 Leuven (Belgium); Everaert, J.-L. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Yang, L. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Department of Chemistry and INPAC Institute, KU Leuven, B-3001 Leuven (Belgium); Goossens, J.; Moussa, A.; Clarysse, T.; Richard, O.; Bender, H. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Zaima, S. [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Nagoya, 464-8603 (Japan); Sakai, A. [Department of System Innovation, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan); Loo, R. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Lin, J.C. [TSMC, R and D, 8, Li-Hsin 6th Rd., Hsinchu Science-Based Park, Hsinchu, Taiwan (China); TSMC assignee at IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Vandervorst, W. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Instituut voor Kern- en Stralingsfysika - IKS, KU Leuven, B-3001 Leuven (Belgium); Caymax, M. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium)

    2010-01-01

    We evaluated the combination of vapor phase doping and sub-melt laser anneal as a novel doping strategy for the fabrication of source and drain extension junctions in sub-32 nm CMOS technology, aiming at both planar and non-planar device applications. High quality ultra shallow junctions with abrupt profiles in Si substrates were demonstrated on 300 mm Si substrates. The excellent results obtained for the sheet resistance and the junction depth with boron allowed us to fulfill the requirements for the 32 nm as well as for the 22 nm technology nodes in the PMOS case by choosing appropriate laser anneal conditions. For instance, using 3 laser scans at 1300 {sup o}C, we measured an active dopant concentration of about 2.1 x 10{sup 20} cm{sup -} {sup 3} and a junction depth of 12 nm. With arsenic for NMOS, ultra shallow junctions were achieved as well. However, as also seen for other junction fabrication schemes, low dopant activation level and active dose (in the range of 1-4 x 10{sup 13} cm{sup -} {sup 2}) were observed although dopant concentration versus depth profiles indicate that the dopant atoms were properly driven into the substrate during the anneal step. The electrical deactivation of a large part of the in-diffused dopants was responsible for the high sheet resistance values.

  6. Use of p- and n-type vapor phase doping and sub-melt laser anneal for extension junctions in sub-32 nm CMOS technology

    International Nuclear Information System (INIS)

    Nguyen, N.D.; Rosseel, E.; Takeuchi, S.; Everaert, J.-L.; Yang, L.; Goossens, J.; Moussa, A.; Clarysse, T.; Richard, O.; Bender, H.; Zaima, S.; Sakai, A.; Loo, R.; Lin, J.C.; Vandervorst, W.; Caymax, M.

    2010-01-01

    We evaluated the combination of vapor phase doping and sub-melt laser anneal as a novel doping strategy for the fabrication of source and drain extension junctions in sub-32 nm CMOS technology, aiming at both planar and non-planar device applications. High quality ultra shallow junctions with abrupt profiles in Si substrates were demonstrated on 300 mm Si substrates. The excellent results obtained for the sheet resistance and the junction depth with boron allowed us to fulfill the requirements for the 32 nm as well as for the 22 nm technology nodes in the PMOS case by choosing appropriate laser anneal conditions. For instance, using 3 laser scans at 1300 o C, we measured an active dopant concentration of about 2.1 x 10 20 cm - 3 and a junction depth of 12 nm. With arsenic for NMOS, ultra shallow junctions were achieved as well. However, as also seen for other junction fabrication schemes, low dopant activation level and active dose (in the range of 1-4 x 10 13 cm - 2 ) were observed although dopant concentration versus depth profiles indicate that the dopant atoms were properly driven into the substrate during the anneal step. The electrical deactivation of a large part of the in-diffused dopants was responsible for the high sheet resistance values.

  7. Magnetic field selective enhancement of Li I lines comparing Li II line in laser ablated lithium plasma at 10- 2 mbar air ambient gas

    Science.gov (United States)

    Liu, Ping; Wu, Ding; Sun, Liying; Hai, Ran; Liu, Jiamin; Ding, Hongbin

    2017-11-01

    In this paper, the effect of magnetic field (1.1 T) on the atomic and ionic spectral emission of a laser produced lithium plasma at low pressure has been investigated. The experimental results indicate that magnetic field enhances the intensities of Li I spectral lines but reduces the Li II spectral lines intensities. In this study, two narrowband filters were placed before the ICCD camera to observe the evolution feature of Li II spectral line (548.39 nm, 2p3P2,1,0 → 2s3S1) and Li I spectral line (610.30 nm, 3d2P3/2, 5/2 → 2p2P1/2, 3/2), respectively. The plasma dynamic images show that with the magnetic field, the number density of luminous Li atoms is higher, while the number density of luminous Li ions is lower in comparison to the field-free case. The reduced Li II spectral intensities indicate that the quenching rate of Li ions in the excited state is greater than that without the magnetic field. The enhanced impact frequency of recombination indicates that magnetic field increases the recombination process of electron and Li ions. All of these observations strongly suggest that magnetic confinement increases the recombination process of the electrons with Li ions in the plasma, which results in the decrease in the intensity of Li II line. The results are useful for applying laser-induced breakdown spectroscopy (LIBS) to in-situ diagnose the processes of lithium wall conditioning in EAST tokamak.

  8. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Oak Ridge Gaseous Diffusion Plant Site

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) technology, with the near-term goal to provide the necessary information to make a deployment decision by November 1992. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. A programmatic document for use in screening DOE sites to locate the U-AVLIS production plant was developed and implemented in two parts (Wolsko et al. 1991). The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were then subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the ORGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use, socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3. Following the site description and additional data requirements, Sec. 4 provides a short, qualitative assessment of potential environmental issues. 37 refs., 20 figs., 18 tabs.

  9. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Oak Ridge Gaseous Diffusion Plant Site

    International Nuclear Information System (INIS)

    1991-09-01

    In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) technology, with the near-term goal to provide the necessary information to make a deployment decision by November 1992. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. A programmatic document for use in screening DOE sites to locate the U-AVLIS production plant was developed and implemented in two parts (Wolsko et al. 1991). The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were then subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the ORGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use, socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3. Following the site description and additional data requirements, Sec. 4 provides a short, qualitative assessment of potential environmental issues. 37 refs., 20 figs., 18 tabs

  10. GaN-based vertical-cavity surface-emitting lasers with tunnel junction contacts grown by metal-organic chemical vapor deposition

    Science.gov (United States)

    Lee, SeungGeun; Forman, Charles A.; Lee, Changmin; Kearns, Jared; Young, Erin C.; Leonard, John T.; Cohen, Daniel A.; Speck, James S.; Nakamura, Shuji; DenBaars, Steven P.

    2018-06-01

    We report the first demonstration of III–nitride vertical-cavity surface-emitting lasers (VCSELs) with tunnel junction (TJ) intracavity contacts grown completely by metal–organic chemical vapor deposition (MOCVD). For the TJs, n++-GaN was grown on in-situ activated p++-GaN after buffered HF surface treatment. The electrical properties and epitaxial morphologies of the TJs were first investigated on TJ LED test samples. A VCSEL with a TJ intracavity contact showed a lasing wavelength of 408 nm, a threshold current of ∼15 mA (10 kA/cm2), a threshold voltage of 7.8 V, a maximum output power of 319 µW, and a differential efficiency of 0.28%.

  11. Generation of InN nanocrystals in organic solution through laser ablation of high pressure chemical vapor deposition-grown InN thin film

    International Nuclear Information System (INIS)

    Alkis, Sabri; Alevli, Mustafa; Burzhuev, Salamat; Vural, Hüseyin Avni; Okyay, Ali Kemal; Ortaç, Bülend

    2012-01-01

    We report the synthesis of colloidal InN nanocrystals (InN-NCs) in organic solution through nanosecond pulsed laser ablation of high pressure chemical vapor deposition-grown InN thin film on GaN/sapphire template substrate. The size, the structural, the optical, and the chemical characteristics of InN-NCs demonstrate that the colloidal InN crystalline nanostructures in ethanol are synthesized with spherical shape within 5.9–25.3, 5.45–34.8, 3.24–36 nm particle-size distributions, increasing the pulse energy value. The colloidal InN-NCs solutions present strong absorption edge tailoring from NIR region to UV region.

  12. Silicon nitride films fabricated by a plasma-enhanced chemical vapor deposition method for coatings of the laser interferometer gravitational wave detector

    Science.gov (United States)

    Pan, Huang-Wei; Kuo, Ling-Chi; Huang, Shu-Yu; Wu, Meng-Yun; Juang, Yu-Hang; Lee, Chia-Wei; Chen, Hsin-Chieh; Wen, Ting Ting; Chao, Shiuh

    2018-01-01

    Silicon is a potential substrate material for the large-areal-size mirrors of the next-generation laser interferometer gravitational wave detector operated in cryogenics. Silicon nitride thin films uniformly deposited by a chemical vapor deposition method on large-size silicon wafers is a common practice in the silicon integrated circuit industry. We used plasma-enhanced chemical vapor deposition to deposit silicon nitride films on silicon and studied the physical properties of the films that are pertinent to application of mirror coatings for laser interferometer gravitational wave detectors. We measured and analyzed the structure, optical properties, stress, Young's modulus, and mechanical loss of the films, at both room and cryogenic temperatures. Optical extinction coefficients of the films were in the 10-5 range at 1550-nm wavelength. Room-temperature mechanical loss of the films varied in the range from low 10-4 to low 10-5 within the frequency range of interest. The existence of a cryogenic mechanical loss peak depended on the composition of the films. We measured the bond concentrations of N - H , Si - H , Si - N , and Si - Si bonds in the films and analyzed the correlations between bond concentrations and cryogenic mechanical losses. We proposed three possible two-level systems associated with the N - H , Si - H , and Si - N bonds in the film. We inferred that the dominant source of the cryogenic mechanical loss for the silicon nitride films is the two-level system of exchanging position between a H+ and electron lone pair associated with the N - H bond. Under our deposition conditions, superior properties in terms of high refractive index with a large adjustable range, low optical absorption, and low mechanical loss were achieved for films with lower nitrogen content and lower N - H bond concentration. Possible pairing of the silicon nitride films with other materials in the quarter-wave stack is discussed.

  13. Lithium Intoxication

    Directory of Open Access Journals (Sweden)

    Sermin Kesebir

    2011-09-01

    Full Text Available Lithium has been commonly used for the treatment of several mood disorders particularly bipolar disorder in the last 60 years. Increased intake and decreased excretion of lithium are the main causes for the development of lithium intoxication. The influence of lithium intoxication on body is evaluated as two different groups; reversible or irreversible. Irreversible damage is usually related with the length of time passed as intoxicated. Acute lithium intoxication could occur when an overdose of lithium is received mistakenly or for the purpose of suicide. Patients may sometimes take an overdose of lithium for self-medication resulting in acute intoxication during chronic, while others could develop chronic lithium intoxication during a steady dose treatment due to a problem in excretion of drug. In such situations, it is crucial to be aware of risk factors, to recognize early clinical symptoms and to conduct a proper medical monitoring. In order to justify or exclude the diagnosis, quantitative evaluation of lithium in blood and toxicologic screening is necessary. Following the monitoring schedules strictly and urgent intervention in case of intoxication would definitely reduce mortality and sequela related with lithium intoxication. In this article, the etiology, frequency, definition, clinical features and treatment approaches to the lithium intoxication have been briefly reviewed.

  14. Lithium-aluminum-zinc phosphate glasses activated with Tb3+ and Tb3+/Eu3+ for green laser medium, reddish-orange and white phosphor applications

    Science.gov (United States)

    Francisco-Rodriguez, H. I.; Lira, A.; Soriano-Romero, O.; Meza-Rocha, A. N.; Bordignon, S.; Speghini, A.; Lozada-Morales, R.; Caldiño, U.

    2018-05-01

    A spectroscopic analysis of Tb3+ and Tb3+/Eu3+ doped lithium-aluminum-zinc phosphate glasses is performed through their absorbance and photoluminescence spectra, and decay time profiles. Laser parameter values (stimulated emission cross section, effective bandwidth, gain bandwidth and optical gain) were obtained for the terbium 5D4 → 7F5 green emission from the Tb3+ singly-doped glass (LAZT) excited at 350 nm to judge the suitability of the glass phosphor for fiber lasers. A quantum yield of (47.68 ± 0.49)% was measured for the 5D4 level luminescence. Upon 350 nm excitation the LAZT glass phosphor emits green light with a color purity of 65.6% and chromaticity coordinates (0.285, 0.585) very close to those (0.29, 0.60) of European Broadcasting Union illuminant green. The Tb3+/Eu3+codoped glass emission color can be tuned from reddish-orange of 1865 K upon 318 nm excitation to warm white of 3599 K and neutral white of 4049 K upon 359 and 340 nm excitations, respectively. Upon Tb3+ excitation at 340 nm Eu3+ is sensitized by Tb3+ through a non-radiative energy transfer with an efficiency of 0.23-0.26. An electric dipole-dipole interaction might be the dominant mechanism in the Tb3+ to Eu3+ energy transfer taking place into Tb3+ - Eu3+ clusters.

  15. GaAs FETs and novel heteroepitaxial quaternary lasers grown on InP substrates by organometallic chemical vapor deposition

    International Nuclear Information System (INIS)

    Lo, Y.H.; Bhat, R.; Chang-Hasnain, C.; Caneau, C.; Zah, C.E.; Lee, T.P.

    1988-01-01

    This paper reports the GaAs MESFETs and 1.3μm buried hetero-structure lasers with AlGaAs/GaAs lateral confinement layers simultaneously grown by OMCVD and fabricated on InP structures. The 1μm recessed gate MESFET has a transconductance of 220 mS/mm and the novel structured laser has a CW threshold current of 45 mA. The heteroepitaxy technology and devices show great promises for long wavelength opto-electronic integrated circuits

  16. Growth and Evaluation of Nonlinear Optical Crystals for Laser Applications: Lithium Borate, Barium Borate and Silver Gallium Selenide.

    Science.gov (United States)

    1994-12-08

    communication 2. S. A. Kutovi, V. V. Laptev and S. Yu. Matsnev, " Lanthanum scandoborate as a new highly efficient active medium of solid state lasers," Sov. J...34Noncritical detection of tunable C02 laser radiation into green by upconversion in silver thio- gallate ," Applied Physics B53, 19 (1991). 3. N.-H

  17. In situ investigation of formation of self-assembled nanodomain structure in lithium niobate after pulse laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shur, V. Ya.; Kuznetsov, D. K.; Mingaliev, E. A.; Yakunina, E. M.; Lobov, A. I.; Ievlev, A. V. [Ferroelectric Laboratory, Institute of Physics and Applied Mathematics, Ural State University, Lenin Ave. 51, Ekaterinburg 620083 (Russian Federation)

    2011-08-22

    The evolution of the self-assembled quasi-regular micro- and nanodomain structures after pulse infrared laser irradiation was studied by in situ optical observation. The average periods of the structures are much less than the sizes of the laser spots. The polarization reversal occurs through covering of the whole irradiated area by the nets of the spatially separated nanodomain chains and microdomain rays--''hatching effect.'' The main stages of the anisotropic nanodomain kinetics: nucleation, growth, and branching, have been singled out. The observed abnormal domain kinetics was attributed to the action of the pyroelectric field arising during cooling after laser heating.

  18. Copper Vapor Laser with One-Beam Radiation of Diffraction Quality and Its Capabilities for Microprocessing of Materials for Electronic Engineering Products

    Directory of Open Access Journals (Sweden)

    N. A. Lyabin

    2014-01-01

    Full Text Available The structure, spatial, time and energy characteristics of copper vapor laser radiation (CVL with optical resonators possessing high spatial selectivity have been investigated: with an unstable resonator (UR with two convex mirrors and telescopic UR, and the conditions to form one-beam radiation with diffraction divergence and high stability of directivity pattern axis have been defined.The most weighty and prospective application of CVL with UR with two convex mirrors is to use it as a driving oscillator (DO in a copper vapor laser system (CVLS of the type: driving oscillator – power amplifier (DO – PA when diffraction beam radiating power and power density in a focused spot of 10-20 µm in diameter increases by 1-2 orders. Using industrial sealed-off active elements (AE of “Kulon” series with an average radiation power of 15-25 W as PAs the peak power density increases up to 1011 W/cm 2 while an application of AE “Crystal” with 30- 50 W power gives up to 1012 W/cm 2 , which is sufficient for efficient and qualitative microprocessing of materials up to 1…2 mm thick. Such a CVLS has become the basis for creating up-to-date automated laser technological installations (ALTI of “Karavella-1” and “Karavella-1M” types to manufacture precision parts of electronic engineering products (EEP of metal up to 0.5 mm thick and of non-metal up to 1.5…1.8 mm thick.CVL with a telescopic UR with an average power of 5-6 W diffraction radiation beam has become the basis for creating industrial ALTI “Karavella-2” and “Karavella-2M” to manufacture precision parts of electronic engineering products (EEP of metal up to 0.3 mm thick and of non-metal up to 0.5 – 0.7 mm thick.Practical work on all types of ALTI “Karavella” has shown a set of significant advantages of a laser way of pulsed microprocessing over the traditional ones, including electro-erosion machining: a wide range of structural metal and non-metal materials to be

  19. Lithium Poisoning

    DEFF Research Database (Denmark)

    Baird-Gunning, Jonathan; Lea-Henry, Tom; Hoegberg, Lotte C G

    2017-01-01

    Lithium is a commonly prescribed treatment for bipolar affective disorder. However, treatment is complicated by lithium's narrow therapeutic index and the influence of kidney function, both of which increase the risk of toxicity. Therefore, careful attention to dosing, monitoring, and titration...... is required. The cause of lithium poisoning influences treatment and 3 patterns are described: acute, acute-on-chronic, and chronic. Chronic poisoning is the most common etiology, is usually unintentional, and results from lithium intake exceeding elimination. This is most commonly due to impaired kidney...... function caused by volume depletion from lithium-induced nephrogenic diabetes insipidus or intercurrent illnesses and is also drug-induced. Lithium poisoning can affect multiple organs; however, the primary site of toxicity is the central nervous system and clinical manifestations vary from asymptomatic...

  20. Stress Dispersed Cu Metal Anode by Laser Multiscale Patterning for Lithium-Ion Batteries with High Capacity

    Directory of Open Access Journals (Sweden)

    Jin-Young So

    2018-06-01

    Full Text Available Electric power production continues to increase as the industry advances, and the demand for high-capacity batteries for efficient operation of the electric power produced is higher than ever before. Si has been attracting a great deal of attention recently as an anode electrode material because of its high theoretical capacity. However, it suffers from significant capacity-loss, resulting from the volume-expansion of Si during charge and discharge cycles. Inspired by the multiscale structures commonly found in nature, we attempt to solve this problem by patterning the surface of the Cu current-collector. To this end, we develop a direct, one-step method using laser patterning to manufacture a multiscale structure on the surface of the current-collector. The inherent exfoliation characteristic of the Cu current-collector allows the spontaneous formation of the multiscale structure while being irradiated with a laser. A micro/nano structure, with a different surface area, is fabricated by varying the laser output at three levels, and the batteries prepared with the fabricated Cu current-collector are tested to evaluate their charge-discharge characteristics and electrochemical impedance. The results show that the multiscale structure reduces mechanical stress. The initial capacity of the Cu current-collector is proportional to the laser output, and the initial capacity of the coin cell prepared with the Cu current-collector, fabricated at the highest laser output, is 396.7% higher than that of the coin cell prepared with a bare Cu current-collector. The impedance is inversely proportional to the laser output. The charge transfer resistance of the coin cell prepared with the Cu current-collector and irradiated with the highest laser output is 190.2% lower than that of the coin cell prepared with the bare Cu current-collector.

  1. Growth of LiMn{sub 2}O{sub 4} thin films by pulsed-laser deposition and their electrochemical properties in lithium microbatteries

    Energy Technology Data Exchange (ETDEWEB)

    Julien, C. [Univ. Pierre et Marie Curie, Paris (France). LMDH; Haro-Poniatowski, E. [Laboratorio de Optica Cuantica, Universidad Autonoma Metropolitana Iztapalapa, Apdo. Postal 55-534, Mexico (Mexico); Camacho-Lopez, M.A. [LMDH, UMR 7603, Universite Pierre et Marie Curie, 4 place Jussieu, 75252, Paris (France); Escobar-Alarcon, L. [Departamento de Fisica, Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, Mexico (Mexico); Jimenez-Jarquin, J. [Laboratorio de Optica Cuantica, Universidad Autonoma Metropolitana Iztapalapa, Apdo. Postal 55-534, Mexico (Mexico)

    2000-03-01

    Films of LiMn{sub 2}O{sub 4} were grown by pulsed-laser deposition (PLD) onto silicon wafers using sintered targets which consisted in the mixture of LiMn{sub 2}O{sub 4} and Li{sub 2}O powders. The film formation has been studied as a function of the preparation conditions, i.e. composition of the target, substrate temperature, and oxygen partial pressure in the deposition chamber. Composition, morphology and structural properties of PLD films have been investigated using Rutherford backscattering spectroscopy, scanning electron microscopy, X-ray diffraction and Raman scattering spectroscopy. The films deposited from target LiMn{sub 2}O{sub 4}+15% Li{sub 2}O have an excellent crystallinity when deposited onto silicon substrate maintained at 300 C in an oxygen partial pressure of 100 mTorr. It is found that such a film crystallizes in the spinel structure (Fd3m symmetry) as evidenced by X-ray diffraction. Well-textured polycrystalline films exhibit crystallite size of 300 nm. Pulsed-laser deposited LiMn{sub 2}O{sub 4} thin films obtained with a polycrystalline morphology were successfully used as cathode materials in lithium microbatteries. The Li//LiMn{sub 2}O{sub 4} thin film cells have been tested by cyclic voltammetry and galvanostatic charge-discharge techniques in the potential range 3.0-4.2 V. Specific capacity as high as 120 mC/cm{sup 2} {mu}m was measured on polycrystalline films. The chemical diffusion coefficients for the Li{sub x}Mn{sub 2}O{sub 4} thin films appear to be in the range of 10{sup -11}-10{sup -12} cm{sup 2}/s. Electrochemical measurements show a good cycleability of PLD films when cells are charged-discharged at current densities of 5-25 {mu}A/cm{sup 2}. (orig.)

  2. Lithium batteries, anodes, and methods of anode fabrication

    KAUST Repository

    Li, Lain-Jong

    2016-12-29

    Prelithiation of a battery anode carried out using controlled lithium metal vapor deposition. Lithium metal can be avoided in the final battery. This prelithiated electrode is used as potential anode for Li- ion or high energy Li-S battery. The prelithiation of lithium metal onto or into the anode reduces hazardous risk, is cost effective, and improves the overall capacity. The battery containing such an anode exhibits remarkably high specific capacity and a long cycle life with excellent reversibility.

  3. Characterization of deuterium retention and co-deposition of fuel with lithium on the divertor tile of EAST using laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Li, Cong; Zhao, Dongye; Hu, Zhenhua; Wu, Xingwei; Luo, Guang-Nan; Hu, Jiansheng; Ding, Hongbin

    2015-01-01

    A laser induced breakdown spectroscopy (LIBS) system has been developed to measure and monitor the composition evolution on plasma facing materials (PFMs) of Experimental Advanced Superconducting Tokamak (EAST). As a necessity and important proof of principle experiment, LIBS analysis has been performed for lithium–deuterium co-deposition layer diagnosis of EAST divertor tiles in lab experiments. The distribution of deuterium retention has been obtained from the depth of 0.5–4 μm in the divertor tiles. The deuterium/hydrogen concentration ratio was estimated as 0.17 ± 0.02 in lithium–deuterium co-deposition layer. Moreover, the depth profile behaviors of lithium and deuterium indicate that the deuterium retention in divertor tile came from lithium–deuterium co-deposition processes during deuterium discharge in EAST. This work would improve the understanding of deuterium retention and lithium–deuterium co-deposition mechanism and give a guidance to optimize the LIBS system which will be a unique and useful diagnostic approach in EAST 2014-campaign

  4. Double-sided laser beam welded T-joints for aluminum-lithium alloy aircraft fuselage panels: Effects of filler elements on microstructure and mechanical properties

    Science.gov (United States)

    Han, Bing; Tao, Wang; Chen, Yanbin; Li, Hao

    2017-08-01

    In the current work, T-joints consisting of 2.0 mm thick 2060-T8/2099-T83 aluminum-lithium alloys for aircraft fuselage panels have been fabricated by double-sided fiber laser beam welding with different filler wires. A new type wire CW3 (Al-6.2Cu-5.4Si) was studied and compared with conventional wire AA4047 (Al-12Si) mainly on microstructure and mechanical properties. It was found that the main combined function of Al-6.2%Cu-5.4%Si in CW3 resulted in considerable improvements especially on intergranular strength, hot cracking susceptibility and hoop tensile properties. Typical non-dendritic equiaxed zone (EQZ) was observed along welds' fusion boundary. Hot cracks and fractures during the load were always located within the EQZ, however, this typical zone could be restrained by CW3, effectively. Furthermore, changing of the main intergranular precipitated phase within the EQZ from T phase by AA4047 to T2 phase by CW3 also resulted in developments on microscopic intergranular reinforcement and macroscopic hoop tensile properties. In addition, bridging caused by richer substructure dendrites within CW3 weld's columnar zone resulted in much lower hot cracking susceptibility of the whole weld than AA4047.

  5. Lithium Batteries

    Science.gov (United States)

    National Laboratory, Materials Science and Technology Division Lithium Batteries Resources with Additional thin-film lithium batteries for a variety of technological applications. These batteries have high essentially any size and shape. Recently, Teledyne licensed this technology from ORNL to make batteries for

  6. Charging-circuit study for copper-vapor lasers. Final report, 29 June 1981-30 November 1981

    International Nuclear Information System (INIS)

    1981-01-01

    This study is divided into three tasks whose combined purpose is to evaluate methods of charging high PRF pulsed power subsystems required in a proposed laser isotope separation (LIS) plant. The work performed in this program follows directly from designs and experiments carried out in a recently-completed study and, in fact, utilizes much of the same apparatus described previously. The first task required the preparation and vugraph presentation of a review of eight potential charging methods. This review and the associated evaluation criteria are described. Tasks II and III entailed the experimental evaluation of the deQing methods of regulating the charging voltage of a pulse power conditioning module with respect to limitations imposed by continuous operation and the efficiency of recovery of energy diverted by the deQing circuitry. The results of these tasks are described

  7. Solid state perovskite solar modules by vacuum-vapor assisted sequential deposition on Nd:YVO_4 laser patterned rutile TiO_2 nanorods

    International Nuclear Information System (INIS)

    Fakharuddin, Azhar; Wali, Qamar; Rauf, Muhammad; Jose, Rajan; Palma, Alessandro L; Giacomo, Francesco Di; Casaluci, Simone; Matteocci, Fabio; Carlo, Aldo Di; Brown, Thomas M

    2015-01-01

    The past few years have witnessed remarkable progress in solution-processed methylammonium lead halide (CH_3NH_3PbX_3, X = halide) perovskite solar cells (PSCs) with reported photoconversion efficiency (η) exceeding 20% in laboratory-scale devices and reaching up to 13% in their large area perovskite solar modules (PSMs). These devices mostly employ mesoporous TiO_2 nanoparticles (NPs) as an electron transport layer (ETL) which provides a scaffold on which the perovskite semiconductor can grow. However, limitations exist which are due to trap-limited electron transport and non-complete pore filling. Herein, we have employed TiO_2 nanorods (NRs), a material offering a two-fold higher electronic mobility and higher pore-filing compared to their particle analogues, as an ETL. A crucial issue in NRs’ patterning over substrates is resolved by using precise Nd:YVO_4 laser ablation, and a champion device with η ∼ 8.1% is reported via a simple and low cost vacuum-vapor assisted sequential processing (V-VASP) of a CH_3NH_3PbI_3 film. Our experiments showed a successful demonstration of NRs-based PSMs via the V-VASP technique which can be applied to fabricate large area modules with a pin-hole free, smooth and dense perovskite layer which is required to build high efficiency devices. (paper)

  8. Bartholin's gland cysts: management with carbon-dioxide laser vaporization Cistos da glândula de Bartholin: tratamento com vaporização laser com CO2

    Directory of Open Access Journals (Sweden)

    Ana Cristina Neves Figueiredo

    2012-12-01

    Full Text Available PURPOSE: To evaluate the effectiveness, recurrence rate, and complications of carbon-dioxide laser vaporization in the treatment of Bartholin's gland cysts. METHODS: A retrospective study including 127 patients with symptomatic Bartholin' gland cysts submitted to carbon-dioxide laser vaporization at our institution from January 2005 to June 2011. Patients with Bartholin's gland abscesses and those suspected of having neoplasia were excluded. All procedures were performed in an outpatient setting under local anaesthesia. Clinical records were reviewed for demographic characteristics, anatomic parameters, intraoperative and postoperative complications, and follow-up data. Data were stored and analyzed in Microsoft Excel® 2007 software. A descriptive statistical analysis was performed, and its results were expressed as frequency (percentage or mean±standard deviation. Complication, recurrence, and cure rates were calculated. RESULTS: The mean age of the patients was 37.3±9.5 years-old (range from 18 to 61 years-old. Seventy percent (n=85 of them were multiparous. The most common symptom was pain and 47.2% (n=60 of patients had a history of previous medical and/or surgical treatment for Bartholin's gland abscesses. Mean cyst size was 2.7±0.9 cm. There were three (2.4% cases of minor intraoperative bleeding. Overall, there were 17 (13.4% recurrences within a mean of 14.6 months (range from 1 to 56 months: ten Bartholin's gland abscesses and seven recurrent cysts requiring reintervention. The cure rate after single laser treatment was 86.6%. Among the five patients with recurrent disease that had a second laser procedure, the cure rate was 100%. CONCLUSIONS: At this institution, carbon-dioxide laser vaporization seems to be a safe and effective procedure for the treatment of Bartholin's gland cysts.OBJETIVO: Avaliar a eficácia, a taxa de recorrência e as complicações da vaporização laser com CO2 no tratamento dos cistos da glândula de

  9. Lithium Surface Coatings for Improved Plasma Performance in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    Kugel, H W; Ahn, J -W; Allain, J P; Bell, R; Boedo, J; Bush, C; Gates, D; Gray, T; Kaye, S; Kaita, R; LeBlanc, B; Maingi, R; Majeski, R; Mansfield, D; Menard, J; Mueller, D; Ono, M; Paul, S; Raman, R; Roquemore, A L; Ross, P W; Sabbagh, S; Schneider, H; Skinner, C H; Soukhanovskii, V; Stevenson, T; Timberlake, J; Wampler, W R

    2008-02-19

    NSTX high-power divertor plasma experiments have shown, for the first time, significant and frequent benefits from lithium coatings applied to plasma facing components. Lithium pellet injection on NSTX introduced lithium pellets with masses 1 to 5 mg via He discharges. Lithium coatings have also been applied with an oven that directed a collimated stream of lithium vapor toward the graphite tiles of the lower center stack and divertor. Lithium depositions from a few mg to 1 g have been applied between discharges. Benefits from the lithium coating were sometimes, but not always seen. These improvements sometimes included decreases plasma density, inductive flux consumption, and ELM frequency, and increases in electron temperature, ion temperature, energy confinement and periods of MHD quiescence. In addition, reductions in lower divertor D, C, and O luminosity were measured.

  10. Lithium neurotoxicity.

    Science.gov (United States)

    Suraya, Y; Yoong, K Y

    2001-09-01

    Inspite of the advent of newer antimanic drugs, lithium carbonate remains widely used in the treatment and prevention of manic-depressive illness. However care has to be exercised due to its low therapeutic index. The central nervous system and renal system are predominantly affected in acute lithium intoxication and is potentially lethal. The more common side effect involves the central nervous system. It occurs early and is preventable. We describe three cases of lithium toxicity admitted to Johor Bahru Hospital, with emphasis on its neurological preponderance.

  11. Sustainability Impact of Nanomaterial Enhanced Lithium Ion Batteries

    Science.gov (United States)

    Ganter, Matthew

    Energy storage devices are becoming an integral part of sustainable energy technology adoption, particularly, in alternative transportation (electric vehicles) and renewable energy technologies (solar and wind which are intermittent). The most prevalent technology exhibiting near-term impact are lithium ion batteries, especially in portable consumer electronics and initial electric vehicle models like the Chevy Volt and Nissan Leaf. However, new technologies need to consider the full life-cycle impacts from material production and use phase performance to the end-of-life management (EOL). This dissertation investigates the impacts of nanomaterials in lithium ion batteries throughout the life cycle and develops strategies to improve each step in the process. The embodied energy of laser vaporization synthesis and purification of carbon nanotubes (CNTs) was calculated to determine the environmental impact of the novel nanomaterial at beginning of life. CNTs were integrated into lithium ion battery electrodes as conductive additives, current collectors, and active material supports to increase power, energy, and thermal stability in the use phase. A method was developed to uniformly distribute CNT conductive additives in composites. Cathode composites with CNT additives had significant rate improvements (3x the capacity at a 10C rate) and higher thermal stability (40% reduction in exothermic energy released upon overcharge). Similar trends were also measured with CNTs in anode composites. Advanced free-standing anodes incorporating CNTs with high capacity silicon and germanium were measured to have high capacities where surface area reduction improved coulombic efficiencies and thermal stability. A thermal stability plot was developed that compares the safety of traditional composites with free-standing electrodes, relating the results to thermal conductivity and surface area effects. The EOL management of nanomaterials in lithium ion batteries was studied and a novel

  12. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

    International Nuclear Information System (INIS)

    Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3

  13. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3.

  14. Fast Growth of GaN Epilayers via Laser-Assisted Metal-Organic Chemical Vapor Deposition for Ultraviolet Photodetector Applications.

    Science.gov (United States)

    Rabiee Golgir, Hossein; Li, Da Wei; Keramatnejad, Kamran; Zou, Qi Ming; Xiao, Jun; Wang, Fei; Jiang, Lan; Silvain, Jean-François; Lu, Yong Feng

    2017-06-28

    In this study, we successfully developed a carbon dioxide (CO 2 )-laser-assisted metal-organic chemical vapor deposition (LMOCVD) approach to fast synthesis of high-quality gallium nitride (GaN) epilayers on Al 2 O 3 [sapphire(0001)] substrates. By employing a two-step growth procedure, high crystallinity and smooth GaN epilayers with a fast growth rate of 25.8 μm/h were obtained. The high crystallinity was confirmed by a combination of techniques, including X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and atomic force microscopy. By optimizing growth parameters, the ∼4.3-μm-thick GaN films grown at 990 °C for 10 min showed a smooth surface with a root-mean-square surface roughness of ∼1.9 nm and excellent thickness uniformity with sharp GaN/substrate interfaces. The full-width at half-maximum values of the GaN(0002) X-ray rocking curve of 313 arcsec and the GaN(101̅2) X-ray rocking curve of 390 arcsec further confirmed the high crystallinity of the GaN epilayers. We also fabricated ultraviolet (UV) photodetectors based on the as-grown GaN layers, which exhibited a high responsivity of 0.108 A W -1 at 367 nm and a fast response time of ∼125 ns, demonstrating its high optical quality with potential in optoelectronic applications. Our strategy thus provides a simple and cost-effective means toward fast and high-quality GaN heteroepitaxy growth suitable for fabricating high-performance GaN-based UV detectors.

  15. Vaporization of irradiated droplets

    International Nuclear Information System (INIS)

    Armstrong, R.L.; O'Rourke, P.J.; Zardecki, A.

    1986-01-01

    The vaporization of a spherically symmetric liquid droplet subject to a high-intensity laser flux is investigated on the basis of a hydrodynamic description of the system composed of the vapor and ambient gas. In the limit of the convective vaporization, the boundary conditions at the fluid--gas interface are formulated by using the notion of a Knudsen layer in which translational equilibrium is established. This leads to approximate jump conditions at the interface. For homogeneous energy deposition, the hydrodynamic equations are solved numerically with the aid of the CON1D computer code (''CON1D: A computer program for calculating spherically symmetric droplet combustion,'' Los Alamos National Laboratory Report No. LA-10269-MS, December, 1984), based on the implict continuous--fluid Eulerian (ICE) [J. Comput. Phys. 8, 197 (1971)] and arbitrary Lagrangian--Eulerian (ALE) [J. Comput. Phys. 14, 1227 (1974)] numerical mehtods. The solutions exhibit the existence of two shock waves propagating in opposite directions with respect to the contact discontinuity surface that separates the ambient gas and vapor

  16. Type-I cascaded quadratic soliton compression in lithium niobate: Compressing femtosecond pulses from high-power fiber lasers

    DEFF Research Database (Denmark)

    Bache, Morten; Wise, Frank W.

    2010-01-01

    The output pulses of a commercial high-power femtosecond fiber laser or amplifier are typically around 300–500 fs with wavelengths of approximately 1030 nm and tens of microjoules of pulse energy. Here, we present a numerical study of cascaded quadratic soliton compression of such pulses in LiNbO3....... However, the strong group-velocity dispersion implies that the pulses can achieve moderate compression to durations of less than 130 fs in available crystal lengths. Most of the pulse energy is conserved because the compression is moderate. The effects of diffraction and spatial walk-off are addressed......, and in particular the latter could become an issue when compressing such long crystals (around 10 cm long). We finally show that the second harmonic contains a short pulse locked to the pump and a long multi-picosecond red-shifted detrimental component. The latter is caused by the nonlocal effects...

  17. Methods of tritium recovery from molten lithium

    International Nuclear Information System (INIS)

    Farookhi, R.; Rogers, J.E.

    1968-01-01

    It is important to keep the tritium inventory in a blanket of a thermonuclear reactor at a low level both to eliminate possible hydriding of structural components and to reduce inventory cost. Removing the tritium from a lithium blanket by fractional distillation, flash vaporization, and fractional crystallization was investigated. No definitive data are available either on the vapor-liquid equilibrium between lithium and tritium at low T 2 concentrations, or on the rate of formation and decomposition of lithium tritide. The final distinction between the recovery systems discussed in this report will depend on such data, but presently distillation appears to be the best alternate to the diffusion scheme proposed by A.P. Fraas. The capital cost of equipment necessary to remove tritium by distillation appears to be greater than 10 million dollars for a 5000 MW system, whereas the capital cost associated with the diffusion process has been estimated to be 4 million dollars

  18. Experimental study of gaseous lithium deuterides and lithium oxides. Implications for the use of lithium and Li2O as breeding materials in fusion reactor blankets

    International Nuclear Information System (INIS)

    Ihle, H.R.; Wu, C.H.; Kudo, H.

    1980-01-01

    In addition to LiH, which has been studied extensively by optical spectroscopy, the existence of a number of other stable lithium hydrides has been predicted theoretically. By analysis of the saturated vapour over dilute solutions of the hydrogen isotopes in lithium, using Knudsen effusion mass spectrometry, all lithium hydrides predicted to be stable were found. Solutions of deuterium in lithium were used predominantly because of practical advantages for mass spectrometric measurements. The heats of dissociation of LiD, Li 2 D, LiD 2 and Li 2 D 2 , and the binding energies of their singly charged positive ions were determined, and the constants of the gas/liquid equilibria were calculated. The existence of these lithium deuterides in the gas phase over solutions of deuterium in lithium leads to enrichment of deuterium in the gas above 1240 K. The enrichment factor, which increases exponentially with temperature and is independent of concentration for low concentrations of deuterium in the liquid, was determined by Rayleigh distillation experiments. It was found that it is thermodynamically possible to separate deuterium from lithium by distillation. One of the alternatives to the use of lithium in (D,T)-fusion reactors as tritium-breeding blanket material is to employ solid lithium oxide. This has a high melting point, a high lithium density and still favourable tritium-breeding properties. Because of its rather high volatility, an experimental study of the vaporization of Li 2 O was undertaken by mass spectrometry. It vaporizes to give lithium and oxygen, and LiO, Li 2 O, Li 3 O and Li 2 O 2 . The molecule Li 3 O was found as a new species. Heats of dissociation, binding energies of the various ions and the constants of the gas/solid equilibria were determined. The effect of using different materials for the Knudsen cells and the relative thermal stabilities of lithium-aluminium oxides were also studied. (author)

  19. Measurement of atmospheric carbon dioxide and water vapor in built-up urban areas in the Gandhinagar-Ahmedabad region in India using a portable tunable diode laser spectroscopy system.

    Science.gov (United States)

    Roy, Anirban; Sharma, Neetesh Kumar; Chakraborty, Arup Lal; Upadhyay, Abhishek

    2017-11-01

    This paper reports open-path in situ measurements of atmospheric carbon dioxide at Gandhinagar (23.2156°N, 72.6369°E) and Ahmedabad (23.0225°N, 72.5714°E) in the heavily industrialized state of Gujarat in western India. Calibration-free second harmonic wavelength modulation spectroscopy (2f WMS) is used to carry out accurate and fully automated measurements. The mean values of the mole fraction of carbon dioxide at four locations were 438 ppm, 495 ppm, 550 ppm, and 740 ppm, respectively. These values are much higher than the current global average of 406.67 ppm. A 1 mW, 2004-nm vertical cavity surface-emitting laser is used to selectively interrogate the R16 transition of carbon dioxide at 2003.5 nm (4991.2585 cm -1 ). The 2f WMS signal corresponding to the gas absorption line shape is simulated using spectroscopic parameters available in the HITRAN database and relevant laser parameters that are extracted in situ from non-absorbing spectral wings of the harmonic signals. The mole fraction of carbon dioxide is extracted in real-time by a MATLAB program from least-squares fit of the simulated 2f WMS signal to the corresponding experimentally obtained signal. A 10-mW, 1392.54-nm distributed feedback laser is used at two of the locations to carry out water vapor measurements using direct absorption spectroscopy. This is the first instance of a portable tunable diode laser spectroscopy system being deployed in an urban location in India to measure atmospheric carbon dioxide and water vapor under varying traffic conditions. The measurements clearly demonstrate the need to adopt tunable diode laser spectroscopy for precise long-term monitoring of greenhouse gases in the Indian subcontinent.

  20. Measurement of Cerium and Gadolinium in Solid Lithium Chloride-Potassium Chloride Salt Using Laser-Induced Breakdown Spectroscopy (LIBS).

    Science.gov (United States)

    Williams, Ammon; Bryce, Keith; Phongikaroon, Supathorn

    2017-10-01

    Pyroprocessing of used nuclear fuel (UNF) has many advantages-including that it is proliferation resistant. However, as part of the process, special nuclear materials accumulate in the electrolyte salt and present material accountability and safeguards concerns. The main motivation of this work was to explore a laser-induced breakdown spectroscopy (LIBS) approach as an online monitoring technique to enhance the material accountability of special nuclear materials in pyroprocessing. In this work, a vacuum extraction method was used to draw the molten salt (CeCl 3 -GdCl 3 -LiCl-KCl) up into 4 mm diameter Pyrex tubes where it froze. The salt was then removed and the solid salt was measured using LIBS and inductively coupled plasma mass spectroscopy (ICP-MS). A total of 36 samples were made that varied the CeCl 3 and GdCl 3 (surrogates for uranium and plutonium, respectively) concentrations from 0.5 wt% to 5 wt%. From these samples, univariate calibration curves for Ce and Gd were generated using peak area and peak intensity methods. For Ce, the Ce 551.1 nm line using the peak area provided the best calibration curve with a limit of detection (LOD) of 0.099 wt% and a root mean squared error of cross-validation (RMSECV) of 0.197 wt%. For Gd, the best curve was generated using the peak intensities of the Gd 564.2 nm line resulting in a LOD of 0.027 wt% and a RMSECV of 0.295 wt%. The RMSECV for the univariate cases were determined using leave-one-out cross-validation. In addition to the univariate calibration curves, partial least squares (PLS) regression was done to develop a calibration model. The PLS models yielded similar results with RMSECV (determined using Venetian blind cross-validation with 17% left out per split) values of 0.30 wt% and 0.29 wt% for Ce and Gd, respectively. This work has shown that solid pyroprocessing salt can be qualitatively and quantitatively monitored using LIBS. This work has the potential of significantly enhancing

  1. Theoretical studies of solar-pumped lasers

    Science.gov (United States)

    Harries, W. L.

    1983-01-01

    Possible types of lasers were surveyed for solar power conversion. The types considered were (1) liquid dye lasers, (2) vapor dye lasers, and (3) nondissociative molecular lasers. These are discussed.

  2. Dynamic loading of the structural wall in a lithium fall fusion reactor

    International Nuclear Information System (INIS)

    Glenn, L.A.

    1979-01-01

    In one version of an inertial confinement fusion (ICF) power reactor, the laser-imploded pellet is surrounded by a thick, annular 'waterfall' of liquid lithium. The fall has three functions: to breed tritium for pellet resupply, to act as an energy sink and heat exchange mdeium with an external power loop, and to protect the first wall of the reactor from excessive neutronic and hydrodynamic loading. Our primary concern here is with this last function. We formulated a simple model of a lithium-fall ICF reactor and calculated the fall disassembly and the subsequent fluid-wall interaction resulting from the energy deposition by the imploded pellet. Two potential mechanisms for wall damage were identified: surface erosion and hoop failure. For single fall designs, the erosion problem appears to be serious. Concentric annuli (multiple fall) or packed jet configurations may be feasible but experiments are needed to clarify the physical model, especially with reg (orig.)ard to /orig.the characteristics of the cavitated liquid lithium and of the two-phase liquid-vapor region.

  3. Fabrication and evaluation of chemically vapor deposited tungsten heat pipe.

    Science.gov (United States)

    Bacigalupi, R. J.

    1972-01-01

    A network of lithium-filled tungsten heat pipes is being considered as a method of heat extraction from high temperature nuclear reactors. The need for material purity and shape versatility in these applications dictates the use of chemically vapor deposited (CVD) tungsten. Adaptability of CVD tungsten to complex heat pipe designs is shown. Deposition and welding techniques are described. Operation of two lithium-filled CVD tungsten heat pipes above 1800 K is discussed.

  4. Study on laser atomic spectroscopy

    International Nuclear Information System (INIS)

    Lee, Jong Min; Song, Kyu Seok; Jeong, Do Young; Kim, Chul Joong; Han, Phil Soon

    1992-01-01

    Electric discharge type atomic vaporizer is developed for the spectroscopic study on actinide elements. Laser induced fluorescence study on actinide elements is performed by using this high temperature type atomizer. For the effective photoionization of elements, copper vapor laser pumped dye laser and electron beam heating type atomic vaporizer are built and their characteristics are measured. In addition, resonance ionization mass spectroscopic analysis for lead sample as well as laser induced fluorescence study on uranium sample in solution phase is made. (Author)

  5. Laser application of heat pipe technology in energy related programs

    International Nuclear Information System (INIS)

    Carbone, R.J.

    1975-01-01

    The design and operating parameters for a heat pipe laser utilizing metal vapors are proposed. The laser would be applied to laser induced fusion, laser induced chemistry, laser isotope separation, and power transport using optical beams. (U.S.)

  6. Electrochemical Model for Ionic Liquid Electrolytes in Lithium Batteries

    International Nuclear Information System (INIS)

    Yoo, Kisoo; Deshpande, Anirudh; Banerjee, Soumik; Dutta, Prashanta

    2015-01-01

    ABSTRACT: Room temperature ionic liquids are considered as potential electrolytes for high performance and safe lithium batteries due to their very low vapor pressure and relatively wide electrochemical and thermal stability windows. Unlike organic electrolytes, ionic liquid electrolytes are molten salts at room temperature with dissociated cations and anions. These dissociated ions interfere with the transport of lithium ions in lithium battery. In this study, a mathematical model is developed for transport of ionic components to study the performance of ionic liquid based lithium batteries. The mathematical model is based on a univalent ternary electrolyte frequently encountered in ionic liquid electrolytes of lithium batteries. Owing to the very high concentration of components in ionic liquid, the transport of lithium ions is described by the mutual diffusion phenomena using Maxwell-Stefan diffusivities, which are obtained from atomistic simulation. The model is employed to study a lithium-ion battery where the electrolyte comprises ionic liquid with mppy + (N-methyl-N-propyl pyrrolidinium) cation and TFSI − (bis trifluoromethanesulfonyl imide) anion. For a moderate value of reaction rate constant, the electric performance results predicted by the model are in good agreement with experimental data. We also studied the effect of porosity and thickness of separator on the performance of lithium-ion battery using this model. Numerical results indicate that low rate of lithium ion transport causes lithium depleted zone in the porous cathode regions as the porosity decreases or the length of the separator increases. The lithium depleted region is responsible for lower specific capacity in lithium-ion cells. The model presented in this study can be used for design of optimal ionic liquid electrolytes for lithium-ion and lithium-air batteries

  7. Mobile vapor recovery and vapor scavenging unit

    International Nuclear Information System (INIS)

    Stokes, C.A.; Steppe, D.E.

    1991-01-01

    This patent describes a mobile anti- pollution apparatus, for the recovery of hydrocarbon emissions. It comprises a mobile platform upon which is mounted a vapor recovery unit for recovering vapors including light hydrocarbons, the vapor recovery unit having an inlet and an outlet end, the inlet end adapted for coupling to an external source of hydrocarbon vapor emissions to recover a portion of the vapors including light hydrocarbons emitted therefrom, and the outlet end adapted for connection to a means for conveying unrecovered vapors to a vapor scavenging unit, the vapor scavenging unit comprising an internal combustion engine adapted for utilizing light hydrocarbon in the unrecovered vapors exiting from the vapor recovery unit as supplemental fuel

  8. Lasers

    CERN Document Server

    Milonni, Peter W

    1988-01-01

    A comprehensive introduction to the operating principles and applications of lasers. Explains basic principles, including the necessary elements of classical and quantum physics. Provides concise discussions of various laser types including gas, solid state, semiconductor, and free electron lasers, as well as of laser resonators, diffraction, optical coherence, and many applications including holography, phase conjugation, wave mixing, and nonlinear optics. Incorporates many intuitive explanations and practical examples. Discussions are self-contained in a consistent notation and in a style that should appeal to physicists, chemists, optical scientists and engineers.

  9. Experimental and theoretical investigations about the vaporization of laser-produced aerosols and individual particles inside inductively-coupled plasmas — Implications for the extraction efficiency of ions prior to mass spectrometry

    International Nuclear Information System (INIS)

    Flamigni, Luca; Koch, Joachim; Günther, Detlef

    2012-01-01

    Current quantification capabilities of laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) are known to be restricted by elemental fractionation as a result of LA-, transport-, and ICP-induced effects which, particularly, may provoke inaccuracies whenever calibration strategies on the basis of non-matrix matched standard materials are applied. The present study is dealing with the role of ICP in this complex scenario. Therefore, the vaporization process of laser-produced aerosols and subsequent diffusion losses occurring inside ICP sources were investigated using 2-D optical emission spectrometry (OES) and ICP-quadrupole (Q)MS of individual particles. For instance, Na- and Ca-specific OES of aerosols produced by LA of silicate glasses or metals revealed axial shifts in the onset and maximum position of atomic emission which were in the range of a few millimeters. The occurrence of these shifts was found to arise from composition-dependent particle/aerosol penetration depths, i.e. the displacement of axial vaporization starting points controlling the ion extraction efficiency through the ICP-MS vacuum interface due to a delayed, diffusion-driven expansion of oxidic vs. metallic aerosols. Furthermore, ICP-QMS of individual particles resulted in 1/e half-value signal durations of approximately 100 μs, which complies with modeled values if OES maxima are assumed to coincide with positions of instantaneous vaporization and starting points for atomic diffusion. To prove phenomena observed for their consistency, in addition, “ab initio” as well as semi-empirical simulations of particle/aerosol penetration depths followed by diffusion-driven expansion was accomplished indicating differences of up to 15% in the relative ion extraction efficiency depending on whether analytes are supplied as metals or oxides. Implications of these findings on the accuracy achievable by state-of-the-art LA-ICP-MS systems are outlined. - Highlights: ► Specification

  10. LEVIS active anode lithium ion source development on PBFA-II

    International Nuclear Information System (INIS)

    Renk, T.J.; Tisone, G.C.; Adams, R.G.; Clark, B.F.; Reyes, C.; Bailey, J.E.; Filuk, A.B.; Desjarlais, M.P.; Johnson, D.J.; Carlson, A.L.; Lake, P.

    1993-01-01

    Experiments are ongoing on the PBFA-II Accelerator (10 MV typical, 50 ns) to optimize an active lithium ion source in a 15-cm focusing Applied-B ion diode using the LEVIS (Laser Evaporation Ion Source) process. Two laser pulses impinge on a thin (500 nm) Li or Li-bearing alloy on an insulating substrate. A Nd:YAG laser beam (1 μm, 8 ns, 0.1--0.2 J/cm 2 ) creates a thin (∼1 mm) Li vapor, which is then ionized by a 30--60 mJ/cm 2 dye laser tuned to the first resonant transition of Li (670.8 nm). In order to achieve a high-purity Li beam on PBFA-II with LEVIS, it has proven necessary to clean the anode surface in some way. The principal technique has been DC-heating of the anode to temperatures of 150--200 C for typically 5 hours, and for as long as 13 hours, prior to machine firing. Use of a LiAg alloy and YAG energy densities of 200 mJ/cm 2 have yielded beams of Li purity greater than 90%. They authors also plan to test a diode configuration that deposits Li in-situ on the anode surface just prior to the machine shot, as an alternative to DC-heating

  11. Petroleum Vapor Intrusion

    Science.gov (United States)

    One type of vapor intrusion is PVI, in which vapors from petroleum hydrocarbons such as gasoline, diesel, or jet fuel enter a building. Intrusion of contaminant vapors into indoor spaces is of concern.

  12. Effect of Pre-Irradiation Annealing and Laser Modification on the Formation of Radiation-Induced Surface Color Centers in Lithium Fluoride

    Science.gov (United States)

    Voitovich, A. P.; Kalinov, V. S.; Novikov, A. N.; Radkevich, A. V.; Runets, L. P.; Stupak, A. P.; Tarasenko, N. V.

    2017-01-01

    It is shown that surface color centers of the same type are formed in the surface layer and in regions with damaged crystal structure inside crystalline lithium fluoride after γ-irradiation. Results are presented from a study of the effect of pre-irradiation annealing on the efficiency with which surface centers are formed in lithium fluoride nanocrystals. Raising the temperature for pre-irradiation annealing from room temperature to 250°C leads to a substantial reduction in the efficiency with which these centers are created. Surface color centers are not detected after γ-irradiation for pre-irradiation annealing temperatures of 300°C and above. Adsorption of atmospheric gases on the crystal surface cannot be regarded as a necessary condition for the formation of radiation-induced surface centers.

  13. The fabrication of vertically aligned and periodically distributed carbon nanotube bundles and periodically porous carbon nanotube films through a combination of laser interference ablation and metal-catalyzed chemical vapor deposition.

    Science.gov (United States)

    Yuan, Dajun; Lin, Wei; Guo, Rui; Wong, C P; Das, Suman

    2012-06-01

    Scalable fabrication of carbon nanotube (CNT) bundles is essential to future advances in several applications. Here, we report on the development of a simple, two-step method for fabricating vertically aligned and periodically distributed CNT bundles and periodically porous CNT films at the sub-micron scale. The method involves laser interference ablation (LIA) of an iron film followed by CNT growth via iron-catalyzed chemical vapor deposition. CNT bundles with square widths ranging from 0.5 to 1.5 µm in width, and 50-200 µm in length, are grown atop the patterned catalyst over areas spanning 8 cm(2). The CNT bundles exhibit a high degree of control over square width, orientation, uniformity, and periodicity. This simple scalable method of producing well-placed and oriented CNT bundles demonstrates a high application potential for wafer-scale integration of CNT structures into various device applications, including IC interconnects, field emitters, sensors, batteries, and optoelectronics, etc.

  14. Jet stability in the lithium fall reactor

    International Nuclear Information System (INIS)

    Kang, S.W.

    1978-01-01

    A preliminary analysis has been made of the various hydrodynamic aspects involved in the stability of a liquid-lithium jet in a laser-fusion reactor, which comprises a part of LLL's laser fusion power-generation concept. Various physical factors that may affect the jet breakup are delineated, and some approximate calculations are performed to determine their relative influences. Areas of uncertainty are pointed out, along with plans for experimental verification or further theoretical analysis

  15. High-contrast sub-Doppler absorption spikes in a hot atomic vapor cell exposed to a dual-frequency laser field

    International Nuclear Information System (INIS)

    Abdel Hafiz, Moustafa; Coget, Grégoire; Boudot, Rodolphe; Brazhnikov, Denis; Taichenachev, Alexei; Yudin, Valeriy; De Clercq, Emeric

    2017-01-01

    The saturated absorption technique is an elegant method widely used in atomic and molecular physics for high-resolution spectroscopy, laser frequency standards and metrology purposes. We have recently discovered that a saturated absorption scheme with a dual-frequency laser can lead to a significant sign reversal of the usual Doppler-free dip, yielding a deep enhanced-absorption spike. In this paper, we report detailed experimental investigations of this phenomenon, together with a full in-depth theoretical description. It is shown that several physical effects can support or oppose the formation of the high-contrast central spike in the absorption profile. The physical conditions for which all these effects act constructively and result in very bright Doppler-free resonances are revealed. Apart from their theoretical interest, results obtained in this manuscript are of great interest for laser spectroscopy and laser frequency stabilization purposes, with applications in laser cooling, matter-wave sensors, atomic clocks or quantum optics. (paper)

  16. A Comparative Study of Potassium Hydroxide versus CO2 Laser Vaporization in The Treatment of Female Genital Warts: A Controlled Clinical Trial.

    Science.gov (United States)

    Asadi, Nasrin; Hemmati, Ensie; Namazi, Golnaz; Jahromi, Mahnaz Pakniat; Sarraf, Zahra; Pazyar, Nader; Salehi, Alireza

    2016-07-01

    Genital warts are the most common viral sexually transmitted disease affecting 1% of the population. A prospective, open-label controlled trial was performed to compare topical 5% potassium hydroxide (KOH) solution with CO2 laser in the treatment of female genital warts. Seventy patients were enrolled in the study after convenience sampling. Right-sided lesions of the patients were treated by CO2 laser every 3 weeks. The left-sided lesions of the same patients were treated by topical 5% KOH solution twice a day using a toothpick with cotton wrap on the tip. The patients were visited at 3, 6, and 9 weeks after initiation of the treatment and followed up for 6 months after the last visit. Out of seventy patients, sixty three completed the study and were analyzed. A total of 56 KOH treated-patients (88.9%) showed complete response. On the other hand, 56 laser-treated patients (88.9%) presented complete clearing of the lesion. There was not any difference in response to both modalities of treatment. Complications of KOH solution and CO2 laser were 24% and 19% respectively (P>0.05), but serious adverse events were not observed. The patients under KOH treatment displayed a recurrence rate of 11.1% (7 cases), while the same patients with CO2 laser therapy demonstrated a recurrence rate of 7.9% (5 cases) (P=0.54). Topical 5% KOH solution was as effective as CO2 laser in the treatment of female genital warts. There was not any serious complication in the application of KOH solution. This could be used as a new treatment for genital warts. IRCT201412207848N1.

  17. Extraction of negative lithium ions from a lithium-containing hydrogen plasma

    International Nuclear Information System (INIS)

    Wada, M.; Sasao, M.

    1996-01-01

    Negative lithium ions (Li - ) were extracted from a 6-cm-diam 7-cm-long negative hydrogen ion (H - ) source to simulate the condition of Li - extraction from a Li vapor introduced ion source for the neutral beam heating. The amount of the Li - current extracted from a hydrogen plasma with Li vapor was comparable to that extracted from a pure Li plasma. However, the amount of the H - current decreased as the H 2 gas pressure in the source decreased due to a getter-pump effect of Li during the introduction of Li vapor. A heat shield installed to keep a high wall temperature was effective in mitigating the pressure decrease. However, the H - current extracted from the ion source equipped with the heat shield became 20% of the original value, as Li vapor was injected into the ion source. copyright 1996 American Institute of Physics

  18. Lithium mass transport in ceramic breeder materials

    International Nuclear Information System (INIS)

    Blackburn, P.E.; Johnson, C.E.

    1990-01-01

    The objective of this activity is to measure the lithium vaporization from lithium oxide breeder material under differing temperature and moisture partial pressure conditions. Lithium ceramics are being investigated for use as tritium breeding materials. The lithium is readily converted to tritium after reacting with a neutron. With the addition of 1000 ppM H 2 to the He purge gas, the bred tritium is readily recovered from the blanket as HT and HTO above 400 degree C. Within the solid, tritium may also be found as LiOT which may transport lithium to cooler parts of the blanket. The pressure of LiOT(g), HTO(g), or T 2 O(g) above Li 2 O(s) is the same as that for reactions involving hydrogen. In our experiments we were limited to the use of hydrogen. The purpose of this work is to investigate the transport of LiOH(g) from the blanket material. 8 refs., 1 fig., 3 tabs

  19. Vaporization of liquid Pb-Li eutectic alloy from 1000K to 1200K - A high temperature mass spectrometric study

    Science.gov (United States)

    Jain, U.; Mukherjee, A.; Dey, G. K.

    2017-09-01

    Liquid lead-lithium eutectic will be used as a coolant in fusion reactor blanket loop. Vapor pressure of the eutectic is an important parameter to accurately predict its in-loop behavior. Past measurements of vapor pressure of the eutectic relied on indirect methods. In this paper, we report for the first time the in-situ vaporization behavior of the liquid alloy between 1042 and 1176 K by Knudsen effusion mass spectrometry (KEMS). It was seen that the vaporization occurred by independent evaporation of lead and lithium. No complex intermetallic vapor was seen in the mass spectra. The partial pressures and enthalpy of vaporization of Pb and Li were evaluated directly from the measured ion intensities formed from the equilibrium vapor over the alloy. The activity of Li over a temperature range of 1042-1176 K was found to be 4.8 × 10-5 to that of pure Li, indicating its very low activity in the alloy.

  20. Visualizing elemental deposition patterns on carbonaceous anodes from lithium ion batteries: A laser ablation-inductively coupled plasma-mass spectrometry study on factors influencing the deposition of lithium, nickel, manganese and cobalt after dissolution and migration from the Li1[Ni1/3Mn1/3Co1/3]O2 and LiMn1.5 Ni0.5O4 cathode

    Science.gov (United States)

    Schwieters, Timo; Evertz, Marco; Fengler, Alexander; Börner, Markus; Dagger, Tim; Stenzel, Yannick; Harte, Patrick; Winter, Martin; Nowak, Sascha

    2018-03-01

    In this study, laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is applied to previously aged carbonaceous anodes from lithium ion batteries (LIBs). These electrodes are treated by cyclic aging in a lithium ion cell set-up against Li1[Ni1/3Mn 1/3Co1/3]O2 = NMC111 to elucidate factors that influence transition metal dissolution (TMD) of the cathode and subsequent deposition on the anode. The investigations are carried out by qualitatively visualizing the 7Li and TM patterns (60Ni, 55Mn and 59Co) of whole coin and pouch-bag electrodes. The lithium, as well as the TM amount, found on the anode, is directly correlated to the applied upper cut-off voltage (4.6, 4.7, 4.8 and 4.9 V) showing more deposition of Li and TMs at elevated voltages. While 7Li shows a more homogeneous pattern, the TM distribution is inhomogeneous but showing a similar pattern for all TMs of the same sample. An unequal pressure distribution, resulting in a nonparallel electrode alignment, on the electrode stack is identified to be responsible for the inhomogeneous TM deposition pattern. This uneven electrode orientation results in different diffusion pathways for the TM migration with regard to the spatial distances.

  1. Lithium batteries; Les accumulateurs au lithium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This workshop on lithium batteries is divided into 4 sections dealing with: the design and safety aspects, the cycling, the lithium intercalation and its modeling, and the electrolytes. These 4 sections represent 19 papers and are completed by a poster session which corresponds to 17 additional papers. (J.S.)

  2. Lithium batteries; Les accumulateurs au lithium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This workshop on lithium batteries is divided into 4 sections dealing with: the design and safety aspects, the cycling, the lithium intercalation and its modeling, and the electrolytes. These 4 sections represent 19 papers and are completed by a poster session which corresponds to 17 additional papers. (J.S.)

  3. Lithium use in batteries

    Science.gov (United States)

    Goonan, Thomas G.

    2012-01-01

    Lithium has a number of uses but one of the most valuable is as a component of high energy-density rechargeable lithium-ion batteries. Because of concerns over carbon dioxide footprint and increasing hydrocarbon fuel cost (reduced supply), lithium may become even more important in large batteries for powering all-electric and hybrid vehicles. It would take 1.4 to 3.0 kilograms of lithium equivalent (7.5 to 16.0 kilograms of lithium carbonate) to support a 40-mile trip in an electric vehicle before requiring recharge. This could create a large demand for lithium. Estimates of future lithium demand vary, based on numerous variables. Some of those variables include the potential for recycling, widespread public acceptance of electric vehicles, or the possibility of incentives for converting to lithium-ion-powered engines. Increased electric usage could cause electricity prices to increase. Because of reduced demand, hydrocarbon fuel prices would likely decrease, making hydrocarbon fuel more desirable. In 2009, 13 percent of worldwide lithium reserves, expressed in terms of contained lithium, were reported to be within hard rock mineral deposits, and 87 percent, within brine deposits. Most of the lithium recovered from brine came from Chile, with smaller amounts from China, Argentina, and the United States. Chile also has lithium mineral reserves, as does Australia. Another source of lithium is from recycled batteries. When lithium-ion batteries begin to power vehicles, it is expected that battery recycling rates will increase because vehicle battery recycling systems can be used to produce new lithium-ion batteries.

  4. Fabrication of three-dimensional crystalline silicon-on-carbon nanotube nanocomposite anode by sputtering and laser annealing for high-performance lithium-ion battery

    Science.gov (United States)

    Kim, Ilwhan; Hyun, Seungmin; Nam, Seunghoon; Lee, Hoo-Jeong; Kang, Chiwon

    2018-05-01

    In this study, we fabricate a three-dimensional (3D) crystalline Si (c-Si)/carbon nanotube (CNT) nanocomposite anode by sputtering Si on 3D CNTs followed by laser annealing for Si crystallization — a simple, cost-effective route — for advanced Li-ion battery (LIB) applications. We use scanning electron microscopy, X-ray diffraction spectroscopy, and Raman spectroscopy to analyze the samples annealed at different laser energy densities. As a result, we confirm that laser annealing enables Si crystallization without damaging the CNTs. We assemble half-type coin cells for the battery performance test: the 3D c-Si/CNT anode sample demonstrates a specific capacity superior to that of its control counterpart; the cyclic stability is also enhanced significantly.

  5. Some characteristics of isotopic separation laser systems

    International Nuclear Information System (INIS)

    Pochon, E.

    1988-01-01

    The principle of Laser Isotope Separation (LIS) is simple and based on either selective electronic photoexcitation and photoionization of atomic vapor, or selective vibrational photoexcitation and photodissociation of molecules in the gas phase. These processes, respectively called SILVA (AVLIS) and SILMO (MLIS) in France, both use specific laser systems with wavelengths spanning from infrared to ultraviolet. This article describes briefly some of the characteristics of a SILVA laser system. Following a three-step process, a SILVA laser system is based on dye copper vapor lasers. The pulse dye lasers provide the tunable laser light and are optically pumped by copper vapor laser operating at high repetition rates. In order to meet plant laser system requirements, the main improvements under way relate to copper vapor laser devices the power capability, efficiency, reliability and lifetime of which have to be increased. 1 fig

  6. Extraction of tritium from liquid lithium by permeation

    International Nuclear Information System (INIS)

    Alire, R.M.

    1978-01-01

    This paper assesses a method for extracting tritium from liquid lithium for specific application to the conceptual laser fusion reactor that uses a continuous lithium ''waterfall.'' The tritium diffuses through a refractory metal that contains a getter and is then stored in a hydride-forming alloy. There are various uncertainties with this method including helium-4 extraction, unknown impurities that may accumulate in liquid lithium, the effects of these impurities on tritium separation, and the maintenance of tritium-contaminated equipment. Our study indicates that major tritium losses will occur during equipment maintenance rather than as a result of permeation losses through the primary vessel

  7. PWFA plasma source - interferometric diagnostics for Li vapor density measurements

    International Nuclear Information System (INIS)

    Sivakumaran, V.; Mohandas, K.K.; Singh, Sneha; Ravi Kumar, A.V.

    2015-01-01

    A prototype (40 cm long) plasma source based on Li heat pipe oven has been developed for the Plasma Wakefield Acceleration (PWFA) experiments at IPR (IPR), Gujarat as a part of the ongoing Accelerator Programme. Li vapor in the oven is produced by heating solid Li in helium buffer gas. A uniform column of Li plasma is generated by UV photo ionization (193 nm) of the Li vapor in the heat pipe oven. In these experiments, an accurate measurement of Li vapor density is important as it has got a direct consequence on the plasma electron density. In the present experiment, the vapor density is measured optically by using Hook method (spectrally resolved white light interferometry). The hook like structure formed near the vicinity of the Li 670.8 nm resonance line was recorded with a white light Mach Zehnder interferometer crossed with an imaging spectrograph to estimate the Li vapor density. The vapor density measurements have been carried out as a function of external oven temperature and the He buffer gas pressure. This technique has the advantage of being insensitive to line broadening and line shape, and its high dynamic range even with optically thick absorption line. Here, we present the line integrated Lithium vapor density measurement using Hook method and also compare the same with other optical diagnostic techniques (White light absorption and UV absorption) for Li vapor density measurements. (author)

  8. High-quality nonpolar a-plane GaN epitaxial films grown on r-plane sapphire substrates by the combination of pulsed laser deposition and metal–organic chemical vapor deposition

    Science.gov (United States)

    Yang, Weijia; Zhang, Zichen; Wang, Wenliang; Zheng, Yulin; Wang, Haiyan; Li, Guoqiang

    2018-05-01

    High-quality a-plane GaN epitaxial films have been grown on r-plane sapphire substrates by the combination of pulsed laser deposition (PLD) and metal–organic chemical vapor deposition (MOCVD). PLD is employed to epitaxial growth of a-plane GaN templates on r-plane sapphire substrates, and then MOCVD is used. The nonpolar a-plane GaN epitaxial films with relatively small thickness (2.9 µm) show high quality, with the full-width at half-maximum values of GaN(11\\bar{2}0) along [1\\bar{1}00] direction and GaN(10\\bar{1}1) of 0.11 and 0.30°, and a root-mean-square surface roughness of 1.7 nm. This result is equivalent to the quality of the films grown by MOCVD with a thickness of 10 µm. This work provides a new and effective approach for achieving high-quality nonpolar a-plane GaN epitaxial films on r-plane sapphire substrates.

  9. Enriched lithium collection from lithium plasma flow

    International Nuclear Information System (INIS)

    Karchevsky, A.I.; Laz'ko, V.S.; Muromkin, Y.A.; Pashkovsky, V.G.; Ustinov, A.L.; Dolgolenko, D.A.

    1994-01-01

    In order to understand the physical processes concerned with the selective heating by ion cyclotron resonance and with the subsequent collection of heated particles, experiments were carried out with the extraction of lithium samples, enriched with 6 Li isotopes. Probe and integral extractors allow to collect enriched Li at the end of the selective heating region. Surface density distribution on the collector and local isotopic content of lithium are measured, as a function of the screen height and the retarding potential. Dependence of the collected amount of lithium and of its isotopic content on the value of the magnetic field is also measured. 4 figs., 2 tabs., 5 refs

  10. A heated vapor cell unit for DAVLL in atomic rubidium

    OpenAIRE

    McCarron, Daniel J.; Hughes, Ifan G.; Tierney, Patrick; Cornish, Simon L.

    2007-01-01

    The design and performance of a compact heated vapor cell unit for realizing a dichroic atomic vapor laser lock (DAVLL) for the D2 transitions in atomic rubidium is described. A 5 cm-long vapor cell is placed in a double-solenoid arrangement to produce the required magnetic field; the heat from the solenoid is used to increase the vapor pressure and correspondingly the DAVLL signal. We have characterized experimentally the dependence of important features of the DAVLL signal on magnetic field...

  11. Secondary electron emission from lithium and lithium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Capece, A. M., E-mail: capecea@tcnj.edu [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Department of Physics, The College of New Jersey, Ewing, New Jersey 08628 (United States); Patino, M. I.; Raitses, Y. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Koel, B. E. [Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08540 (United States)

    2016-07-04

    In this work, measurements of electron-induced secondary electron emission (SEE) yields of lithium as a function of composition are presented. The results are particularly relevant for magnetic fusion devices such as tokamaks, field-reversed configurations, and stellarators that consider Li as a plasma-facing material for improved plasma confinement. SEE can reduce the sheath potential at the wall and cool electrons at the plasma edge, resulting in large power losses. These effects become significant as the SEE coefficient, γ{sub e}, approaches one, making it imperative to maintain a low yield surface. This work demonstrates that the yield from Li strongly depends on chemical composition and substantially increases after exposure to oxygen and water vapor. The total yield was measured using a retarding field analyzer in ultrahigh vacuum for primary electron energies of 20–600 eV. The effect of Li composition was determined by introducing controlled amounts of O{sub 2} and H{sub 2}O vapor while monitoring film composition with Auger electron spectroscopy and temperature programmed desorption. The results show that the energy at which γ{sub e} = 1 decreases with oxygen content and is 145 eV for a Li film that is 17% oxidized and drops to less than 25 eV for a fully oxidized film. This work has important implications for laboratory plasmas operating under realistic vacuum conditions in which oxidation significantly alters the electron emission properties of Li walls.

  12. Secondary electron emission from lithium and lithium compounds

    International Nuclear Information System (INIS)

    Capece, A. M.; Patino, M. I.; Raitses, Y.; Koel, B. E.

    2016-01-01

    In this work, measurements of electron-induced secondary electron emission (SEE) yields of lithium as a function of composition are presented. The results are particularly relevant for magnetic fusion devices such as tokamaks, field-reversed configurations, and stellarators that consider Li as a plasma-facing material for improved plasma confinement. SEE can reduce the sheath potential at the wall and cool electrons at the plasma edge, resulting in large power losses. These effects become significant as the SEE coefficient, γ e , approaches one, making it imperative to maintain a low yield surface. This work demonstrates that the yield from Li strongly depends on chemical composition and substantially increases after exposure to oxygen and water vapor. The total yield was measured using a retarding field analyzer in ultrahigh vacuum for primary electron energies of 20–600 eV. The effect of Li composition was determined by introducing controlled amounts of O 2 and H 2 O vapor while monitoring film composition with Auger electron spectroscopy and temperature programmed desorption. The results show that the energy at which γ e  = 1 decreases with oxygen content and is 145 eV for a Li film that is 17% oxidized and drops to less than 25 eV for a fully oxidized film. This work has important implications for laboratory plasmas operating under realistic vacuum conditions in which oxidation significantly alters the electron emission properties of Li walls.

  13. Fabrication of nanoscale patterns in lithium fluoride crystal using a 13.5 nm Schwarzschild objective and a laser produced plasma source

    International Nuclear Information System (INIS)

    Wang Xin; Mu Baozhong; Jiang Li; Zhu Jingtao; Yi Shengzhen; Wang Zhanshan; He Pengfei

    2011-01-01

    Lithium fluoride (LiF) crystal is a radiation sensitive material widely used as EUV and soft x-ray detector. The LiF-based detector has high resolution, in principle limited by the point defect size, large field of view, and wide dynamic range. Using LiF crystal as an imaging detector, a resolution of 900 nm was achieved by a projection imaging of test meshes with a Schwarzschild objective operating at 13.5 nm. In addition, by imaging of a pinhole illuminated by the plasma, an EUV spot of 1.5 μm diameter in the image plane of the objective was generated, which accomplished direct writing of color centers with resolution of 800 nm. In order to avoid sample damage and contamination due to the influence of huge debris flux produced by the plasma source, a spherical normal-incidence condenser was used to collect EUV radiation. Together with a description of experimental results, the development of the Schwarzschild objective, the influence of condenser on energy density and the alignment of the imaging system are also reported.

  14. Evaporation monitoring and composition control of alloy systems with widely differing vapor pressures

    International Nuclear Information System (INIS)

    Anklam, T.M.; Berzins, L.V.; Braun, D.G.; Haynam, C.; McClelland, M.A.; Meier, T.

    1994-10-01

    Lawrence Livermore National Laboratory is developing sensors and controls to improve and extend electron beam materials processing technology to alloy systems with constituents of widely varying vapor pressure. The approach under development involves using tunable lasers to measure the density and composition of the vapor plume. A laser based vaporizer control system for vaporization of a uranium-iron alloy has been previously demonstrated in multi-hundred hour, high rate vaporization experiments at LLNL. This paper reviews the design and performance of the uranium vaporization sensor and control system and discusses the extension of the technology to monitoring of uranium vaporization. Data is presented from an experiment in which titanium wire was fed into a molten niobium pool. Laser data is compared to deposited film composition and film cross sections. Finally, the potential for using this technique for composition control in melting applications is discussed

  15. Lithium and trace-element concentrations in trioctahedral micas from granites of different geochemical types measured via laser ablation ICP-MS

    Czech Academy of Sciences Publication Activity Database

    Breiter, Karel; Vaňková, M.; Vašinová Galiová, M.; Korbelová, Zuzana; Kanický, V.

    2017-01-01

    Roč. 81, č. 1 (2017), s. 15-33 ISSN 0026-461X R&D Projects: GA ČR GA14-13600S Institutional support: RVO:67985831 Keywords : trioctahedral micas * Li-mica * rare-metal granite * Bohemian Massif * laser ablation inductively coupled plasma mass spectrometry Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Mineralogy Impact factor: 1.285, year: 2016

  16. SEPARATION OF WATER VAPORS FROM AIR BY SORPTION ON SOME COMPOSITE MATERIALS

    Directory of Open Access Journals (Sweden)

    OANA HAUTĂ

    2014-01-01

    Full Text Available This work presents an experimental investigation of the kinetics of water vapor sorption on two composites synthesized by impregnating activated carbon and activated alumina respectively with lithium bromide (named as MCA2 and MCC2 respectively. The obtained results showed an increase in water amount adsorbed on both composite materials. Due to different chemical natures of the host matrices, the water sorption kinetics on MCC2 is faster compared to that of MCA2. The presence of calcium chloride instead of lithium bromide in alumina pores will determine a shorter breakthrough time and a higher adsorption rate of water vapors.

  17. Lithium-thionyl chloride battery

    Science.gov (United States)

    Wong, D.; Bowden, W.; Hamilton, N.; Cubbison, D.; Dey, A. N.

    1981-04-01

    The main objective is to develop, fabricate, test, and deliver safe high rate lithium-thionyl chloride batteries for various U.S. Army applications such as manpack ratios and GLLD Laser Designators. We have devoted our efforts in the following major areas: (1) Optimization of the spirally wound D cell for high rate applications, (2) Development of a 3 inch diameter flat cylindrical cell for the GLLD laser designator application, and (3) Investigation of the reduction mechanism of SOCl2. The rate capability of the spirally wound D cell previously developed by us has been optimized for both the manpack radio (BA5590) battery and GLLD laser designator battery application in this program. A flat cylindrical cell has also been developed for the GLLD laser designator application. It is 3 inches in diameter and 0.9 inch in height with extremely low internal cell impedance that minimizes cell heating and polarization on the GLLD load. Typical cell capacity was found to be 18.0-19.0 Ahr with a few cells delivering up to about 21.0 Ahr on the GLLD test load. Study of the reduction mechanism of SOCl2 using electrochemical and spectroscopic techniques has also been carried out in this program which may be directly relevant to the intrinsic safety of the system.

  18. Experimental lithium system experience

    International Nuclear Information System (INIS)

    Atwood, J.M.; Berg, J.D.; Kolowith, R.; Miller, W.C.

    1984-01-01

    The Experimental Lithium System is a test loop built to support design and operation of the Fusion Materials Irradiation Test Facility. ELS has achieved over 15,000 hours of safe and reliable operation. An extensive test program has demonstrated satisfactory performance of the system components, including an electromagnetic pump, lithium jet target, and vacuum system. Data on materials corrosion and behavior of lithium impurities are also presented. (author)

  19. High temperature measurement of water vapor absorption

    Science.gov (United States)

    Keefer, Dennis; Lewis, J. W. L.; Eskridge, Richard

    1985-01-01

    An investigation was undertaken to measure the absorption coefficient, at a wavelength of 10.6 microns, for mixtures of water vapor and a diluent gas at high temperature and pressure. The experimental concept was to create the desired conditions of temperature and pressure in a laser absorption wave, similar to that which would be created in a laser propulsion system. A simplified numerical model was developed to predict the characteristics of the absorption wave and to estimate the laser intensity threshold for initiation. A non-intrusive method for temperature measurement utilizing optical laser-beam deflection (OLD) and optical spark breakdown produced by an excimer laser, was thoroughly investigated and found suitable for the non-equilibrium conditions expected in the wave. Experiments were performed to verify the temperature measurement technique, to screen possible materials for surface initiation of the laser absorption wave and to attempt to initiate an absorption wave using the 1.5 kW carbon dioxide laser. The OLD technique was proven for air and for argon, but spark breakdown could not be produced in helium. It was not possible to initiate a laser absorption wave in mixtures of water and helium or water and argon using the 1.5 kW laser, a result which was consistent with the model prediction.

  20. Fuel vapor pressure (FVAPRS)

    International Nuclear Information System (INIS)

    Mason, R.E.

    1979-04-01

    A subcode (FVAPRS) is described which calculates fuel vapor pressure. This subcode was developed as part of the fuel rod behavior modeling task performed at EG and G Idaho, Inc. The fuel vapor pressure subcode (FVAPRS), is presented and a discussion of literature data, steady state and transient fuel vapor pressure equations and estimates of the standard error of estimate to be expected with the FVAPRS subcode are included

  1. Lithium Battery Diaper Ulceration.

    Science.gov (United States)

    Maridet, Claire; Taïeb, Alain

    2016-01-01

    We report a case of lithium battery diaper ulceration in a 16-month-old girl. Gastrointestinal and ear, nose, and throat lesions after lithium battery ingestion have been reported, but skin involvement has not been reported to our knowledge. © 2015 Wiley Periodicals, Inc.

  2. Cathode material for lithium batteries

    Science.gov (United States)

    Park, Sang-Ho; Amine, Khalil

    2013-07-23

    A method of manufacture an article of a cathode (positive electrode) material for lithium batteries. The cathode material is a lithium molybdenum composite transition metal oxide material and is prepared by mixing in a solid state an intermediate molybdenum composite transition metal oxide and a lithium source. The mixture is thermally treated to obtain the lithium molybdenum composite transition metal oxide cathode material.

  3. Startup of Experimental Lithium System

    International Nuclear Information System (INIS)

    McCauley, D.L.

    1980-06-01

    The Experimental Lithium System (ELS) is designed for full-scale testing of targets and other lithium system components for the Fusion Materials Irradiation Test (FMIT) Facility. The system also serves as a test bed for development of lithium purification and characterization equipment, provides experience in operation of large lithium systems, and helps guide FMIT design

  4. Lithium purity and characterization

    International Nuclear Information System (INIS)

    Meadows, G.E.; Keough, R.F.

    1981-02-01

    The accurate measurement of impurities in lithium is basic to the study of lithium compatibility with fusion reactor materials. In the last year the Hanford Engineering Development Laboratory (HEDL) has had the opportunity to develop sampling and analytical techniques and to apply them in support of the Experimental Lithium System (ELS) as a part of the Fusion Materials Irradiation Test Project. In this paper we present the analytical results from the fill, start-up and operation of the ELS. In addition, the analysis and purification of navy surplus ingot lithium which is being considered for use in a larger system will be discussed. Finally, the analytical techniques used in our laboratory will be summarized and the results of a recent round robin lithium analysis will be presented

  5. Lithium and Renal Impairment

    DEFF Research Database (Denmark)

    Nielsen, René Ernst; Kessing, Lars Vedel; Nolen, Willem A

    2018-01-01

    INTRODUCTION: Lithium is established as an effective treatment of mania, of depression in bipolar and unipolar disorder, and in maintenance treatment of these disorders. However, due to the necessity of monitoring and concerns about irreversible adverse effects, in particular renal impairment......, after long-term use, lithium might be underutilized. METHODS: This study reviewed 6 large observational studies addressing the risk of impaired renal function associated with lithium treatment and methodological issues impacting interpretation of results. RESULTS: An increased risk of renal impairment...... associated with lithium treatment is suggested. This increased risk may, at least partly, be a result of surveillance bias. Additionally, the earliest studies pointed toward an increased risk of end-stage renal disease associated with lithium treatment, whereas the later and methodologically most sound...

  6. The effect of lithium surface coatings on plasma performance in the National Spherical Torus Experiment

    International Nuclear Information System (INIS)

    Kugel, H.; Bell, M.; Ahn, J.W.; Bush, C.E.; Maingi, R.

    2008-01-01

    National Spherical Torus Experiment (which M. Ono, Nucl. Fusion 40, 557 (2000)) high-power divertor plasma experiments have shown, for the first time, that benefits from lithium coatings applied to plasma facing components found previously in limited plasmas can occur also in high-power diverted configurations. Lithium coatings were applied with pellets injected into helium discharges, and also with an oven that directed a collimated stream of lithium vapor toward the graphite tiles of the lower center stack and divertor. Lithium oven depositions from a few milligrams to 1 g have been applied between discharges. Benefits from the lithium coatings were sometimes, but not always, seen. These benefits sometimes included decreases in plasma density, inductive flux consumption, and edge-localized mode occurrence, and increases in electron temperature, ion temperature, energy confinement, and periods of edge and magnetohydrodynamic quiescence. In addition, reductions in lower divertor D, C, and O luminosity were measured.

  7. Physical model for vaporization

    OpenAIRE

    Garai, Jozsef

    2006-01-01

    Based on two assumptions, the surface layer is flexible, and the internal energy of the latent heat of vaporization is completely utilized by the atoms for overcoming on the surface resistance of the liquid, the enthalpy of vaporization was calculated for 45 elements. The theoretical values were tested against experiments with positive result.

  8. Petroleum Vapor - Field Technical

    Science.gov (United States)

    The screening approach being developed by EPA OUST to evaluate petroleum vapor intrusion (PVI) requires information that has not be routinely collected in the past at vapor intrusion sites. What is the best way to collect this data? What are the relevant data quality issues and ...

  9. Microfabrication process for patterning metallic lithium encapsulated electrodes

    International Nuclear Information System (INIS)

    Oukassi, Sami; Dunoyer, Nicolas; Salot, Raphael; Martin, Steve

    2009-01-01

    This work presents recent achievements concerning thin film encapsulation of metallic lithium negative electrode. In the context of this study, the encapsulation stack includes polymer and dielectric layers combined in such way to optimize barrier performances of the whole structure towards oxygen and water vapor permeation. The first part of this work is dedicated to the description of the barrier stack architecture and properties. A second part presents the application of a microfabrication process to the metallic lithium negative electrode and barrier stack so as to have very small features (100 μm x 100 μm patterns). The microfabrication process includes several steps of photolithography and etching (dry and wet) blocks, which allows us to reach the target critical dimensions. These results show a method of patterning functional metallic lithium. It demonstrates the feasibility of energy sources miniaturization which is an important issue in the field of autonomous and wireless sensor networks.

  10. Pulsed laser deposited heterogeneous mixture of Li2Se-Sb2Se3 nanocomposite as a new storage lithium material

    International Nuclear Information System (INIS)

    Yu Le; Chen Jie; Fu Zhengwen

    2010-01-01

    Li 2 Se-Sb 2 Se 3 nanocomposites with a highly heterogeneous mixture have been fabricated by reactive pulsed laser deposition method. The electrochemical properties of the as-deposited Li 2 Se-Sb 2 Se 3 thin film during the first charging and discharging have been investigated by the galvanostatic cycling and cyclic voltammetry measurements for the first time. By using ex situ X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and selected-area electron diffraction (SAED) measurements, the decomposition of Li 2 Se driven by Sb 2 Se 3 under the electrochemical potential is revealed. In the first cycle, the oxidation peaks at 2.5 V and 3.2 V and the reduction peaks at 2.0 V can be attributed to the decomposition and formation of Li 2 Se with the conversion reaction of Sb 2 Se 3 into Sb 2 Se 5 . Our findings demonstrate that nanocomposite Li 2 Se-Sb 2 Se 3 can possess very high electrochemical activity. These results present a special case of solid-state heterogeneous electrochemistry with both nanostructured binary materials.

  11. Reactor concepts for laser fusion

    International Nuclear Information System (INIS)

    Meier, W.R.; Maniscalco, J.A.

    1977-07-01

    Scoping studies were initiated to identify attractive reactor concepts for producing electric power with laser fusion. Several exploratory reactor concepts were developed and are being subjected to our criteria for comparing long-range sources of electrical energy: abundance, social costs, technical feasibility, and economic competitiveness. The exploratory concepts include: a liquid-lithium-cooled stainless steel manifold, a gas-cooled graphite manifold, and fluidized wall concepts, such as a liquid lithium ''waterfall'', and a ceramic-lithium pellet ''waterfall''. Two of the major reactor vessel problems affecting the technical feasibility of a laser fusion power plant are: the effects of high-energy neutrons and cyclical stresses on the blanket structure and the effects of x-rays and debris from the fusion microexplosion on the first-wall. The liquid lithium ''waterfall'' concept is presented here in more detail as an approach which effectively deals with these damaging effects

  12. Recent experimental results on solutions of deuterium in lithium

    International Nuclear Information System (INIS)

    Ihle, H.R.; Wu, C.H.

    1976-01-01

    The existence of a number of stable molecules containing lithium and hydrogen isotopes in the saturated vapor over dilute solutions of hydrogen isotopes in lithium causes an unexpectedly high density of hydrogen isotopes in the vapor at high temperature. An evaluation of the partial pressures of the gas species Li, Li 2 , LiD, Li 2 D, LiD 2 and D 2 over solutions of deuterium in lithium measured in the temperature range 770 to 970 0 K, and extrapolation to higher temperatures, leads to the conclusion that the ratio of the atom fraction of deuterium in the gas to its atom fraction in the liquid exceeds unity above approximately 1240 0 K; this ratio is independent of the deuterium atom fraction in the liquid at low concentrations. Therefore the thermodynamic supposition that hydrogen isotopes can be separated from lithium by fractional distillation even at extremely low concentration exists. A direct verification of this phenomenon was made by Rayleigh distillation of Li-D solutions in the temperature range 970 to 1600 0 K. These measurements yield also the ratio of the deuterium atom fraction in the gas to that in the liquid and are in good agreement with the data obtained by extrapolation of partial pressures. The enrichment and depletion of deuterium in dependence on the number of theoretical plates of a distillation column at total reflux is calculated using the results

  13. Monitoring uranium, hydrogen, and lithium and their isotopes using a compact laser-induced breakdown spectroscopy (LIBS) probe and high-resolution spectrometer.

    Science.gov (United States)

    Cremers, David A; Beddingfield, Alan; Smithwick, Robert; Chinni, Rosemarie C; Jones, C Randy; Beardsley, Burt; Karch, Larry

    2012-03-01

    The development of field-deployable instruments to monitor radiological, nuclear, and explosive (RNE) threats is of current interest for a number of assessment needs such as the on-site screening of suspect facilities and nuclear forensics. The presence of uranium and plutonium and radiological materials can be determined through monitoring the elemental emission spectrum using relatively low-resolution spectrometers. In addition, uranium compounds, explosives, and chemicals used in nuclear fuel processing (e.g., tributyl-phosphate) can be identified by applying chemometric analysis to the laser-induced breakdown (LIBS) spectrum recorded by these spectrometers. For nuclear forensic applications, however, isotopes of U and Pu and other elements (e.g., H and Li) must also be determined, requiring higher resolution spectrometers given the small magnitude of the isotope shifts for some of these elements (e.g., 25 pm for U and 13 pm for Pu). High-resolution spectrometers will be preferred for several reasons but these must fit into realistic field-based analysis scenarios. To address the need for field instrumentation, we evaluated a previously developed field-deployable hand-held LIBS interrogation probe combined with two relatively new high-resolution spectrometers (λ/Δλ ~75,000 and ~44,000) that have the potential to meet field-based analysis needs. These spectrometers are significantly smaller and lighter in weight than those previously used for isotopic analysis and one unit can provide simultaneous wide spectral coverage and high resolution in a relatively small package. The LIBS interrogation probe was developed initially for use with low resolution compact spectrometers in a person-portable backpack LIBS instrument. Here we present the results of an evaluation of the LIBS probe combined with a high-resolution spectrometer and demonstrate rapid detection of isotopes of uranium and hydrogen and highly enriched samples of (6)Li and (7)Li. © 2012 Society for

  14. Piezoelectric trace vapor calibrator

    International Nuclear Information System (INIS)

    Verkouteren, R. Michael; Gillen, Greg; Taylor, David W.

    2006-01-01

    The design and performance of a vapor generator for calibration and testing of trace chemical sensors are described. The device utilizes piezoelectric ink-jet nozzles to dispense and vaporize precisely known amounts of analyte solutions as monodisperse droplets onto a hot ceramic surface, where the generated vapors are mixed with air before exiting the device. Injected droplets are monitored by microscope with strobed illumination, and the reproducibility of droplet volumes is optimized by adjustment of piezoelectric wave form parameters. Complete vaporization of the droplets occurs only across a 10 deg. C window within the transition boiling regime of the solvent, and the minimum and maximum rates of trace analyte that may be injected and evaporated are determined by thermodynamic principles and empirical observations of droplet formation and stability. By varying solution concentrations, droplet injection rates, air flow, and the number of active nozzles, the system is designed to deliver--on demand--continuous vapor concentrations across more than six orders of magnitude (nominally 290 fg/l to 1.05 μg/l). Vapor pulses containing femtogram to microgram quantities of analyte may also be generated. Calibrated ranges of three explosive vapors at ng/l levels were generated by the device and directly measured by ion mobility spectrometry (IMS). These data demonstrate expected linear trends within the limited working range of the IMS detector and also exhibit subtle nonlinear behavior from the IMS measurement process

  15. Low pressure lithium condensation

    International Nuclear Information System (INIS)

    Wadkins, R.P.; Oh, C.H.

    1985-01-01

    A low pressure experiment to evaluate the laminar film condensation coefficients of lithium was conducted. Some thirty-six different heat transfer tests were made at system pressures ranging from 1.3 to 26 Pa. Boiled lithium was condensed on the inside of a 7.6-cm (ID), 409 stainless-steel pipe. Condensed lithium was allowed to reflux back to the pool boiling region below the condensing section. Fourteen chromel/alumel thermocouples were attached in various regions of the condensing section. The thermocouples were initially calibrated with errors of less than one degree Celsius

  16. Copper laser diagnostics and kinetics support

    International Nuclear Information System (INIS)

    1981-12-01

    In the effort MSNW participated with the LINL copper-Vapor Laser Program by providing a useful plasma diagnostic for interpretation of Copper-vapor laser kinetics. MSNW developed and delivered a pulsed interferometric diagnostic package to LLNL. Moreover MSNW provided personal services at the request and direction of LLL in the implementation of the diagnostic and interpretation of the data

  17. Spectrochemical analysis using laser plasma excitation

    International Nuclear Information System (INIS)

    Radziemski, L.J.

    1989-01-01

    This paper reports on analyses of gases, liquids, particles, and surfaces in which laser plasma is used to vaporize and excite a material. The authors present a discussion of the interaction between laser radiation and a solid and some recent analytical results using laser plasma excitation on metals. The use of laser plasmas as an ablation source is also discussed

  18. Improvements to vapor generators

    International Nuclear Information System (INIS)

    Keller, Arthur; Monroe, Neil.

    1976-01-01

    A supporting system is proposed for vapor generators of the 'supported' type. Said supporting system is intended to compensate the disparities of thermal expansion due to the differences in the vertical dimensions of the tubes in the walls of the combustion chamber and their collectors compared to that of the balloon tanks and the connecting tube clusters of vaporization, the first one being longer than the second ones. Said system makes it possible to build said combustion chamber higher than the balloon tanks and the tube clusters of vaporization. The capacity of steam production is thus enhanced [fr

  19. Observation and particle simulation of vaporized W, Mo, and Be in PISCES-B plasma for vapor-shielding studies

    Directory of Open Access Journals (Sweden)

    K. Ibano

    2017-08-01

    Full Text Available Interactions of Tungsten (W, Molybdenum (Mo, and Beryllium (Be vapors with a steady-state plasma were studied by the PISCES-B liner plasma experiments as well as Particle-In-Cell (PIC simulations for the understanding of vapor-shielding phenomena. Effective cooling of the plasma by laser-generated Be vapor was observed in PISCES-B. On the other hand, no apparent cooling was observed for W and Mo vapors. The PIC simulation explains these experimental observations of the difference between low-Z and high-Z vapors. Decrease of electron temperature due to the vapor ejection was observed in case of a simulation of the Be vapor. As for the W vapor, it was found that the plasma cooling is localized only near the wall at a higher electron density plasma (∼1019m−3. On the other hand, the appreciable plasma cooling can be observed in a lower density plasma (∼1018m−3 for the W vapor.

  20. Laser spectroscopy and laser isotope separation of atomic gadolinium

    International Nuclear Information System (INIS)

    Chen, Y. W.; Yamanaka, C.; Nomaru, K.; Kou, K.; Niki, H.; Izawa, Y.; Nakai, S.

    1994-01-01

    Atomic vapor laser isotope separation (AVLIS) is a process which uses intense pulsed lasers to selectively photoionize one isotopic species of a chemical element, after which these ions are extracted electromagnetically. The AVLIS has several advantages over the traditional methods based on the mass difference, such as high selectivity, low energy consumption, short starting time and versatility to any atoms. The efforts for atomic vapor laser isotope separation at ILT and ILE, Osaka University have been concentrated into the following items: 1) studies on laser spectroscopy and laser isotope separation of atomic gadolinium, 2) studies on interaction processes including coherent dynamics, propagation effects and atom-ion collision in AVLIS system, 3) development of laser systems for AVLIS. In this paper, we present experimental results on the laser spectroscopy and laser isotope separation of atomic gadolinium.

  1. APPARATUS FOR THE PRODUCTION OF LITHIUM METAL

    Science.gov (United States)

    Baker, P.S.; Duncan, F.R.; Greene, H.B.

    1961-08-22

    Methods and apparatus for the production of high-purity lithium from lithium halides are described. The apparatus is provided for continuously contacting a molten lithium halide with molten barium, thereby forming lithium metal and a barium halide, establishing separate layers of these reaction products and unreacted barium and lithium halide, and continuously withdrawing lithium and barium halide from the reaction zone. (AEC)

  2. Atomic vapor laser isotope separation in France

    International Nuclear Information System (INIS)

    Camarcat, N.; Lafon, A.; Perves, J.P.; Rosengard, A.

    1992-01-01

    The main effort in the field of Isotopic Separation Research and Development in France is devoted since 1985 to the 'SILVA' process. A structured organization has been set up, including the following elements: Specific Research and Development for all the functions and components of the process: this work is supported by numerous benches located in Saclay and Pierrelatte. Each bench is mainly devoted to one process function; regarding process and operating performances are optimized. Integrated Experiences in a Pilot facility. Qualified components are integrated in a pilot facility located in Saclay, the capacity of which is steadily increased. At each stage, complete separative experiments demonstrate the improvements attained. Focused Basic Research for each field, often linked with various and relatively original phenomenas. Models have been built up, supported by specific experiments and values attained for intrinsical parameters. An aggregated process performance computing code integrates all the models, possibly under simplified form. Technical, operating and economical data are gradually added. A general assessment will take place in the middle of the nineties with several technical demonstrations and a complete evaluation of the French AVLIS process

  3. Atomic vapor laser isotope separation in France

    Science.gov (United States)

    Camarcat, Noel; Lafon, Alain; Perves, Jean-Pierre; Rosengard, Alex; Sauzay, Guy

    1993-05-01

    France has developed a very complete nuclear industry, from mining to reprocessing and radwastes management, and now has a major electro-nuclear park, with 55 power reactors, supplying 75% of the nation's electricity and representing 32% of its energy requirements. The modern multinational EURODIF enrichment plant in Pierrelatte in the south of the country supplies these reactors with enriched uranium as well as foreign utilities (30% exports). It works smoothly and has continuously been improved to reduce operating costs and to gain flexibility and longevity. Investment costs will be recovered at the turn of the century. The plant will be competitive well ahead of an aging production park, with large overcapacity, in other countries. Meanwhile, world needs will increase only slightly during the next 15 years, apart from the Asian Pacific area, but many world governments are becoming well aware of the necessity to progressively resume nuclear energy development worldwide from the year 2000 on.

  4. Lithium niobate packaging challenges

    International Nuclear Information System (INIS)

    Murphy, E.J.; Holmes, R.J.; Jander, R.B.; Schelling, A.W.

    1988-01-01

    The use of lithium niobate integrated optic devices outside of the research laboratory is predicated on the development of a sound packaging method. The authors present a discussion of the many issues that face the development of a viable, robust packaging technology. The authors emphasize the interaction of lithium niobate's physical properties with available packaging materials and technologies. The broad range of properties (i.e. electro-optic, piezo-electric, pyro-electric, photorefractive...) that make lithium niobate an interesting material in many device applications also make it a packaging challenge. The package design, materials and packaging technologies must isolate the device from the environment so that lithium niobate's properties do not adversely affect the device performance

  5. Gasoline Reid Vapor Pressure

    Science.gov (United States)

    EPA regulates the vapor pressure of gasoline sold at retail stations during the summer ozone season to reduce evaporative emissions from gasoline that contribute to ground-level ozone and diminish the effects of ozone-related health problems.

  6. Solid-state lithium battery

    Science.gov (United States)

    Ihlefeld, Jon; Clem, Paul G; Edney, Cynthia; Ingersoll, David; Nagasubramanian, Ganesan; Fenton, Kyle Ross

    2014-11-04

    The present invention is directed to a higher power, thin film lithium-ion electrolyte on a metallic substrate, enabling mass-produced solid-state lithium batteries. High-temperature thermodynamic equilibrium processing enables co-firing of oxides and base metals, providing a means to integrate the crystalline, lithium-stable, fast lithium-ion conductor lanthanum lithium tantalate (La.sub.1/3-xLi.sub.3xTaO.sub.3) directly with a thin metal foil current collector appropriate for a lithium-free solid-state battery.

  7. Characterization lithium mineralized pegmatite

    International Nuclear Information System (INIS)

    Pereira, E.F.S.; Luz Ferreira, O. da; Cancado, R.Z.L.

    1986-01-01

    Lithium economic importance has increased in the last years. In Brazil its reserves, generally pegmatites bodies, are found in Itinga-Aracuai-MG. This study of characterization belongs to a global plan of lithium mineralized bodies research of 'Arqueana de Minerios e Metais Ltda', which purpose is to give subsidies for implementation of pegmatite unit, in order to make better use of them. (F.E.) [pt

  8. Lithium battery management system

    Science.gov (United States)

    Dougherty, Thomas J [Waukesha, WI

    2012-05-08

    Provided is a system for managing a lithium battery system having a plurality of cells. The battery system comprises a variable-resistance element electrically connected to a cell and located proximate a portion of the cell; and a device for determining, utilizing the variable-resistance element, whether the temperature of the cell has exceeded a predetermined threshold. A method of managing the temperature of a lithium battery system is also included.

  9. Airborne differential absorption lidar system for water vapor investigations

    Science.gov (United States)

    Browell, E. V.; Carter, A. F.; Wilkerson, T. D.

    1981-01-01

    Range-resolved water vapor measurements using the differential-absorption lidar (DIAL) technique is described in detail. The system uses two independently tunable optically pumped lasers operating in the near infrared with laser pulses of less than 100 microseconds separation, to minimize concentration errors caused by atmospheric scattering. Water vapor concentration profiles are calculated for each measurement by a minicomputer, in real time. The work is needed in the study of atmospheric motion and thermodynamics as well as in forestry and agriculture problems.

  10. R-22 vapor explosions

    International Nuclear Information System (INIS)

    Anderson, R.P.; Armstrong, D.R.

    1977-01-01

    Previous experimental and theoretical studies of R-22 vapor explosions are reviewed. Results from two experimental investigations of vapor explosions in a medium scale R-22/water system are reported. Measurements following the drop of an unrestrained mass of R-22 into a water tank demonstrated the existence of two types of interaction behavior. Release of a constrained mass of R-22 beneath the surface of a water tank improved the visual resolution of the system thus allowing identification of two interaction mechansims: at low water temperatures, R-22/water contact would produce immediate violent boiling; at high water temperatures a vapor film formed around its R-22 as it was released, explosions were generated by a surface wave which initiated at a single location and propagated along the vapor film as a shock wave. A new vapor explosion model is proposed, it suggests explosions are the result of a sequence of three independent steps: an initial mixing phase, a trigger and growth phase, and a mature phase where a propagating shock wave accelerates the two liquids into a collapsing vapor layer causing a high velocity impact which finely fragments and intermixes the two liquids

  11. Laser Materials and Laser Spectroscopy - A Satellite Meeting of IQEC '88

    Science.gov (United States)

    Wang, Zhijiang; Zhang, Zhiming

    1989-03-01

    * Mixing Frequency Generation of 271.0 - 291.5 nm in β - BaB2O4 * Low Temperature Absorption Steps Near Ultraviolet Intrinsic Edge in Beta Barium Metaborate * The Growth and Properties of BaTiO3 Crystals * High-order Phenomena Accompanied with Self-pumped Phase Conjugation in BaTiO * Growth and Laser Damage Estimation of Potassium Dihydrogen Phosphate Crystals for Laser Fusion * Noncritically Phase-matched KTP for Diode-pumped Lasers (400-700 nm) * Potassium Titanyl Phosphate (KTP): Properties and New Applications * A Kind of New Defect in KTP Crystal and its SHG Enhanced Effect * Nucleation and Growth of the Non-linear Optical Crystal Potassium Pentaborate Tetrahydrate * Quasi-periodic Oscillations in Photoinduced Conical Light Scattering from LiNbO3 : Fe Crystals * Laser Excited Photoreflectance of GaxIn1-xAs/InP Multiple Quantum Wells * Growth, Spectroscopic Properties and Applications of Doped LiNbO3 Crystals * Photorefractive and Photovoltaic Effect in Doped LiNbO3 * Recent Advances in Photorefractive Nonlinear Optics * Study on the Doubling-frequency and Anti-photorefractive Property of Heavily Magnesium-doped Lithium-rich Lithium Niobate Crystals * A New Technique for Increasing Two-wave Mixing Gain in Photorefractive Bi12SiO20 Crystals * Experimental Proof: There Existing Another Mechanism of Photorefractive Index in Crystal Ce-SBN * Effect of Crystal Annealing on Holographic Recording in Bismuth Silicon Oxide * Two Wave Coupling in KNbO3 Photorefractive Crystal * Photorefractive Effects in Nd-Doped Ferroelectric (KxNa1-x)0.4-(SryBa1-y)0.8 Nb2O6 Single Crystal * High Pressure Raman Spectra and the Effect of Pressure to the Ferroelastic Phase Transition in LnP5O15 * Time-delay Four-wave Mixing with Incoherent Light in Absorption Bands Treated as a Multi-level System * Pulsed Laser Induced Dislocation Structure in Lithium Fluoride Single Crystals * Laser Spectroscopy * Nonclassical Radiation from Single-atom Oscillators * Laser Spectroscopic Studies of Molecules in

  12. Solid Lithium Ion Conductors (SLIC) for Lithium Solid State Batteries

    Data.gov (United States)

    National Aeronautics and Space Administration — To identify the most lithium-ion conducting solid electrolytes for lithium solid state batteries from the emerging types of solid electrolytes, based on a...

  13. Lithium isotope effect accompanying electrochemical intercalation of lithium into graphite

    CERN Document Server

    Yanase, S; Oi, T

    2003-01-01

    Lithium has been electrochemically intercalated from a 1:2 (v/v) mixed solution of ethylene carbonate (EC) and methylethyl carbonate (MEC) containing 1 M LiClO sub 4 into graphite, and the lithium isotope fractionation accompanying the intercalation was observed. The lighter isotope was preferentially fractionated into graphite. The single-stage lithium isotope separation factor ranged from 1.007 to 1.025 at 25 C and depended little on the mole ratio of lithium to carbon of the lithium-graphite intercalation compounds (Li-GIC) formed. The separation factor increased with the relative content of lithium. This dependence seems consistent with the existence of an equilibrium isotope effect between the solvated lithium ion in the EC/MEC electrolyte solution and the lithium in graphite, and with the formation of a solid electrolyte interfaces on graphite at the early stage of intercalation. (orig.)

  14. Laser cooling at resonance

    Science.gov (United States)

    Yudkin, Yaakov; Khaykovich, Lev

    2018-05-01

    We show experimentally that three-dimensional laser cooling of lithium atoms on the D2 line is possible when the laser light is tuned exactly to resonance with the dominant atomic transition. Qualitatively, it can be understood by applying simple Doppler cooling arguments to the specific hyperfine structure of the excited state of lithium atoms, which is both dense and inverted. However, to build a quantitative theory, we must resolve to a full model which takes into account both the entire atomic structure of all 24 Zeeman sublevels and the laser light polarization. Moreover, by means of Monte Carlo simulations, we show that coherent processes play an important role in showing consistency between the theory and the experimental results.

  15. Water vapor differential absorption lidar development and evaluation

    Science.gov (United States)

    Browell, E. V.; Wilkerson, T. D.; Mcllrath, T. J.

    1979-01-01

    A ground-based differential absorption lidar (DIAL) system is described which has been developed for vertical range-resolved measurements of water vapor. The laser transmitter consists of a ruby-pumped dye laser, which is operated on a water vapor absorption line at 724.372 nm. Part of the ruby laser output is transmitted simultaneously with the dye laser output to determine atmospheric scattering and attenuation characteristics. The dye and ruby laser backscattered light is collected by a 0.5-m diam telescope, optically separated in the receiver package, and independently detected using photomultiplier tubes. Measurements of vertical water vapor concentration profiles using the DIAL system at night are discussed, and comparisons are made between the water vapor DIAL measurements and data obtained from locally launched rawinsondes. Agreement between these measurements was found to be within the uncertainty of the rawinsonde data to an altitude of 3 km. Theoretical simulations of this measurement were found to give reasonably accurate predictions of the random error of the DIAL measurements. Confidence in these calculations will permit the design of aircraft and Shuttle DIAL systems and experiments using simulation results as the basis for defining lidar system performance requirements

  16. Lithium: for harnessing renewable energy

    Science.gov (United States)

    Bradley, Dwight; Jaskula, Brian W.

    2014-01-01

    Lithium, which has the chemical symbol Li and an atomic number of 3, is the first metal in the periodic table. Lithium has many uses, the most prominent being in batteries for cell phones, laptops, and electric and hybrid vehicles. Worldwide sources of lithium are broken down by ore-deposit type as follows: closed-basin brines, 58%; pegmatites and related granites, 26%; lithium-enriched clays, 7%; oilfield brines, 3%; geothermal brines, 3%; and lithium-enriched zeolites, 3% (2013 statistics). There are over 39 million tons of lithium resources worldwide. Of this resource, the USGS estimates there to be approximately 13 million tons of current economically recoverable lithium reserves. To help predict where future lithium supplies might be located, USGS scientists study how and where identified resources are concentrated in the Earth’s crust, and they use that knowledge to assess the likelihood that undiscovered resources also exist.

  17. Characteristics of a high current ion source operated with lithium

    International Nuclear Information System (INIS)

    Bay, H.L.; Dullni, E.; Leismann, P.

    1986-05-01

    A low pressure arc ion source has been tested for operation with lithium. Currents up to 120 mA could be extracted through a multiple aperture extraction system at energies of 30 keV. The ion beam was neutralized up to 70% in a charge exchange cell filled with lithium vapour. The beam divergence ranged from 20 to 25 mrad full angle deduced from the spatial distribution of the collision induced Li I resonance line. Current densities from 2 to 3 mA/m 2 at a distance of 1.9 m from the source were measured either by laser induced fluorescence or with a Faraday cup. (orig.)

  18. Lithium-induced downbeat nystagmus.

    Science.gov (United States)

    Schein, Flora; Manoli, Pierre; Cathébras, Pascal

    2017-09-01

    We report the case of a 76-year old lady under lithium carbonate for a bipolar disorder who presented with a suspected optic neuritis. A typical lithium-induced downbeat nystagmus was observed. Discontinuation of lithium therapy resulted in frank improvement in visual acuity and disappearance of the nystagmus.

  19. Vapor pressures and enthalpies of vaporization of azides

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Emel'yanenko, Vladimir N.; Algarra, Manuel; Manuel Lopez-Romero, J.; Aguiar, Fabio; Enrique Rodriguez-Borges, J.; Esteves da Silva, Joaquim C.G.

    2011-01-01

    Highlights: → We prepared and measured vapor pressures and vaporization enthalpies of 7 azides. → We examined consistency of new and available in the literature data. → Data for geminal azides and azido-alkanes selected for thermochemical calculations. - Abstract: Vapor pressures of some azides have been determined by the transpiration method. The molar enthalpies of vaporization Δ l g H m of these compounds were derived from the temperature dependencies of vapor pressures. The measured data sets were successfully checked for internal consistency by comparison with vaporization enthalpies of similarly structured compounds.

  20. Solid State Transmitters for Water Vapor and Ozone DIAL Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The focus of this Select Phase II program is to build and deliver laser components both for airborne water vapor and ozone DIAL systems. Specifically, Fibertek...

  1. Solid State Transmitters for Water Vapor and Ozone DIAL Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We have developed a common architecture for laser transmitters that address requirements for water vapor as well as ground and airborne ozone lidar systems. Our...

  2. A Two-Line Absorption Instrument for Scramjet Temperature and Water Vapor Concentration Measurement in HYPULSE

    Science.gov (United States)

    Tsai, C. Y.

    1998-01-01

    A three beam water vapor sensor system has been modified to provide for near simultaneous temperature measurement. The system employs a tunable diode laser to scan spectral line of water vapor. The application to measurements in a scramjet combustor environment of a shock tunnel facility is discussed. This report presents and discusses die initial calibration of the measurement system.

  3. A Microdrop Generator for the Calibration of a Water Vapor Isotope Ratio Spectrometer

    NARCIS (Netherlands)

    Iannone, Rosario Q.; Romanini, Daniele; Kassi, Samir; Meijer, Harro A. J.; Kerstel, Erik R. Th.

    A microdrop generator is described that produces water vapor with a known isotopic composition and volume mixing ratio for the calibration of a near-infrared diode laser water isotope ratio spectrometer. The spectrometer is designed to measure in situ the water vapor deuterium and oxygen ((17)O and

  4. Dependence of the cutoff in lithium plasma harmonics on the delay between the prepulse and the main pulse

    International Nuclear Information System (INIS)

    Suzuki, M; Baba, M; Kuroda, H; Ganeev, R A; Bom, L B Elouga; Ozaki, T

    2012-01-01

    We demonstrated the generation of the 43rd harmonic at the wavelength of 18.49 nm (67 eV photon energy) by using laser-ablation lithium plasma irradiated by a Ti:sapphire laser pulse. We found that for low-Z material, such as lithium, the cutoff energy depends strongly on the delay time between the prepulse and the main pulse, due to rapid recombination. As a result, the maximum cutoff energy was obtained at a relatively short delay of 24 ns. From the theoretical cutoff rule and hydrodynamic simulations, we show that these harmonics were generated from singly charged lithium ions. (paper)

  5. Lithium extractive metallurgy

    International Nuclear Information System (INIS)

    Josa, J.M.; Merino, J.L.

    1985-01-01

    The Nuclear Fusion National Program depends on lithium supplies. Extractive metallurgy development is subordinate to the localization and evaluation of ore resources. Nowadays lithium raw materials usable with present technology consist of pegmatite ore and brine. The Instituto Geologico y Minero Espanol (IGME) found lepidolite, ambligonite and spodrimene in pegmatite ores in different areas of Spain. However, an evaluation of resources has not been made. Different Spanish surface and underground brines are to be sampled and analyzed. If none of these contain significant levels of lithium, the Junta de Energia Nuclear (JEN) will try an agreement with IGME for ENUSA (Empresa Nacional del Uranio, S.A.) to explore pegmatite-ore bodies from different locations. Different work stages, laboratory tests, pilots plants tests and commercial plant, are foreseen, if the deposits are found. (author)

  6. Preparation of lithium deuteride laser fusion targets

    International Nuclear Information System (INIS)

    Prevender, T.S.; Lynch, A.W.

    1977-01-01

    Techniques for the handling and spheroidization of LiD powders are presented. Particle inspection procedures and a description of both the mathematical and experimental aspects of LiD isotope and exchange experiments are also described

  7. Wavefront reversal in a copper vapor active medium

    Energy Technology Data Exchange (ETDEWEB)

    Bunkin, F.V.; Savranskii, V.V.; Shafeev, G.A.

    1981-09-01

    Wavefront reversal in the resonator of a copper vapor laser was observed. The frequencies of the signal and reversed waves were the same. The dependence of the reversed signal power on the input signal power had a threshold. Photographs were obtained of the reconstructed image of an object when a distorting phase plate was inserted in the resonator.

  8. Large lithium loop experience

    International Nuclear Information System (INIS)

    Kolowith, R.; Owen, T.J.; Berg, J.D.; Atwood, J.M.

    1981-10-01

    An engineering design and operating experience of a large, isothermal, lithium-coolant test loop are presented. This liquid metal coolant loop is called the Experimental Lithium System (ELS) and has operated safely and reliably for over 6500 hours through September 1981. The loop is used for full-scale testing of components for the Fusion Materials Irradiation Test (FMIT) Facility. Main system parameters include coolant temperatures to 430 0 C and flow to 0.038 m 3 /s (600 gal/min). Performance of the main pump, vacuum system, and control system is discussed. Unique test capabilities of the ELS are also discussed

  9. Lithium Combustion: A Review

    Science.gov (United States)

    1990-12-01

    Rev. 2-89) Precribed by ANSI Std 239.18 298-102 UNCLASSIFIED SECURIT CLASSIRCTIO OF THIS PAGE (Whun Data Entered) Lade Form 296 ledk (Row. 2-49...did not burn spontaneously in water, and the hydrogen formed did not ignite in air. When a pea-sized piece of lithium was dropped into a container of...Lithium metal flowed through the cracks in the coating and started to burn brilliantly. The LiOH coating was initially protective; but, as it became

  10. Dissolution behavior of lithium compounds in ethanol

    Directory of Open Access Journals (Sweden)

    Tomohiro Furukawa

    2016-12-01

    Full Text Available In order to exchange the components which received irradiation damage during the operation at the International Fusion Materials Irradiation Facility, the adhered lithium, which is partially converted to lithium compounds such as lithium oxide and lithium hydroxide, should be removed from the components. In this study, the dissolution experiments of lithium compounds (lithium nitride, lithium hydroxide, and lithium oxide were performed in a candidate solvent, allowing the clarification of time and temperature dependence. Based on the results, a cleaning procedure for adhered lithium on the inner surface of the components was proposed.

  11. Liquid Lithium Limiter Effects on Tokamak Plasmas and Plasma-Liquid Surface Interactions

    Energy Technology Data Exchange (ETDEWEB)

    R. Kaita; R. Majeski; R. Doerner; G. Antar; M. Baldwin; R. Conn; P. Efthimion; M. Finkenthal; D. Hoffman; B. Jones; S. Krashenninikov; H. Kugel; S. Luckhardt; R. Maingi; J. Menard; T. Munsat; D. Stutman; G. Taylor; J. Timberlake; V. Soukhanovskii; D. Whyte; R. Woolley; L. Zakharov

    2002-10-15

    We present results from the first experiments with a large area liquid lithium limiter in a magnetic fusion device, and its effect on improving plasma performance by reducing particle recycling. Using large area liquid metal surfaces in any major fusion device is unlikely before a test on a smaller scale. This has motivated its demonstration in the CDX-U spherical torus with a unique, fully toroidal lithium limiter. The highest current discharges were obtained with a liquid lithium limiter. There was a reduction in recycling, as indicated by a significant decrease in the deuterium-alpha emission and oxygen radiation. How these results might extrapolate to reactors is suggested in recycling/retention experiments with liquid lithium surfaces under high-flux deuterium and helium plasma bombardment in PISCES-B. Data on deuterium atoms retained in liquid lithium indicate retention of all incident ions until full volumetric conversion to lithium deuteride. The PISCES-B results also show a material loss mechanism that lowers the maximum operating temperature compared to that for the liquid surface equilibrium vapor pressure. This may restrict the lithium temperature in reactors.

  12. Liquid Lithium Limiter Effects on Tokamak Plasmas and Plasma-Liquid Surface Interactions

    International Nuclear Information System (INIS)

    Kaita, R.; Majeski, R.; Doerner, R.; Antar, G.; Baldwin, M.; Conn, R.; Efthimion, P.; Finkenthal, M.; Hoffman, D.; Jones, B.; Krashenninikov, S.; Kugel, H.; Luckhardt, S.; Maingi, R.; Menard, J.; Munsat, T.; Stutman, D.; Taylor, G.; Timberlake, J.; Soukhanovskii, V.; Whyte, D.; Woolley, R.; Zakharov, L.

    2002-01-01

    We present results from the first experiments with a large area liquid lithium limiter in a magnetic fusion device, and its effect on improving plasma performance by reducing particle recycling. Using large area liquid metal surfaces in any major fusion device is unlikely before a test on a smaller scale. This has motivated its demonstration in the CDX-U spherical torus with a unique, fully toroidal lithium limiter. The highest current discharges were obtained with a liquid lithium limiter. There was a reduction in recycling, as indicated by a significant decrease in the deuterium-alpha emission and oxygen radiation. How these results might extrapolate to reactors is suggested in recycling/retention experiments with liquid lithium surfaces under high-flux deuterium and helium plasma bombardment in PISCES-B. Data on deuterium atoms retained in liquid lithium indicate retention of all incident ions until full volumetric conversion to lithium deuteride. The PISCES-B results also show a material loss mechanism that lowers the maximum operating temperature compared to that for the liquid surface equilibrium vapor pressure. This may restrict the lithium temperature in reactors

  13. Liquid lithium limiter effects on tokamak plasmas and plasma-liquid surface interactions

    International Nuclear Information System (INIS)

    Kaita, R.; Majeski, R.; Doerner, R.

    2003-01-01

    We present results from the first experiments with a large area liquid lithium limiter in a magnetic fusion device, and its effect on improving plasma performance by reducing particle recycling. Using large area liquid metal surfaces in any major fusion device is unlikely before a test on a smaller scale. This has motivated its demonstration in the CDX-U spherical torus with a unique, fully toroidal lithium limiter. The highest current discharges were obtained with a liquid lithium limiter. There was a reduction in recycling, as indicated by a significant decrease in the deuterium-alpha emission and oxygen radiation. How these results might extrapolate to reactors is suggested in recycling/retention experiments with liquid lithium surfaces under high-flux deuterium and helium plasma bombardment in PISCES-B. Data on deuterium atoms retained in liquid lithium indicate retention of all incident ions until full volumetric conversion to lithium deuteride. The PISCES-B results also show a material loss mechanism that lowers the maximum operating temperature compared to that for the liquid surface equilibrium vapor pressure. This may restrict the lithium temperature in reactors. (author)

  14. Soft X-ray imaging by optically stimulated luminescence from color centers in lithium fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Bonfigli, F. [ENEA, C.R. Frascati, Via E. Fermi, 45, 00044 Frascati (Rome) (Italy)], E-mail: bonfigli@frascati.enea.it; Almaviva, S.; Baldacchini, G.; Bollanti, S.; Flora, F.; Lai, A.; Montereali, R.M. [ENEA, C.R. Frascati, Via E. Fermi, 45, 00044 Frascati (Rome) (Italy); Nichelatti, E. [ENEA, C.R. Casaccia, Via Anguillarese 301, 00060 S.Maria di Galeria (Rome) (Italy); Tomassetti, G.; Ritucci, A.; Reale, L. [Universita de L' Aquila e INFN, Dip. di Fisica, Coppito, L' Aquila (Italy); Faenov, A. Ya.; Pikuz, T.A. [MISDC of VNIIFTRI Mendeleevo, Moscow region, 141570 (Russian Federation); Larciprete, R. [ISC-CNR, Sezione Montelibretti, Via Salaria, Km. 29.3, 00016 Monterotondo Scalo (Rome) (Italy); Gregoratti, L.; Kiskinova, M. [Sincrotrone Trieste, S. S. 14, Km. 163.5, 34012 Basovizza (TS) (Italy)

    2007-07-15

    An innovative X-ray imaging detector based on Optically Stimulated Luminescence from color centers in lithium fluoride is presented. Regular photoluminescent patterns produced on LiF samples by different intense X-ray sources, like synchrotrons, laser plasma sources and a capillary discharge laser have been investigated by a Confocal Laser Scanning Microscope. The use of a LiF-based imaging plate for X-ray microscopy is also discussed showing microradiographies of small animals.

  15. Vapor liquid fraction determination

    International Nuclear Information System (INIS)

    1980-01-01

    This invention describes a method of measuring liquid and vapor fractions in a non-homogeneous fluid flowing through an elongate conduit, such as may be required with boiling water, non-boiling turbulent flows, fluidized bed experiments, water-gas mixing analysis, and nuclear plant cooling. (UK)

  16. Heat of vaporization spectrometer

    International Nuclear Information System (INIS)

    Edwards, D. Jr.

    1978-01-01

    Multilayer desorption measurements of various substances adsorbed on a stainless steel substrate are found to exhibit desorption profiles consistent with a zeroth order desorption model. The singleness of the desorption transients together with their narrow peak widths makes the technique ideally suited for a heat of vaporization spectrometer for either substance analysis or identification

  17. Enthalpy of Vaporization and Vapor Pressures: An Inexpensive Apparatus

    Science.gov (United States)

    Battino, Rubin; Dolson, David A.; Hall, Michael A.; Letcher, Trevor M.

    2007-01-01

    A simple and inexpensive method to determine the enthalpy of vaporization of liquids by measuring vapor pressure as a function of temperature is described. The vapor pressures measured with the stopcock cell were higher than the literature values and those measured with the sidearm rubber septum cell were both higher and lower than literature…

  18. Lasers for isotope separation processes and their properties

    International Nuclear Information System (INIS)

    George, E.V.; Krupke, W.F.

    1976-08-01

    The laser system requirements for isotope enrichment are presented in the context of an atomic uranium vapor process. Coherently pumped dye lasers using as the pump laser either the frequency doubled Nd:YAG or copper vapor are seen to be quite promising for meeting the near term requirements of a laser isotope separation (LIS) process. The utility of electrical discharge excitation of the rare gas halogens in an LIS context is discussed

  19. Lithium alloy negative electrodes

    Science.gov (United States)

    Huggins, Robert A.

    The 1996 announcement by Fuji Photo Film of the development of lithium batteries containing convertible metal oxides has caused a great deal of renewed interest in lithium alloys as alternative materials for use in the negative electrode of rechargeable lithium cells. The earlier work on lithium alloys, both at elevated and ambient temperatures is briefly reviewed. Basic principles relating thermodynamics, phase diagrams and electrochemical properties under near-equilibrium conditions are discussed, with the Li-Sn system as an example. Second-phase nucleation, and its hindrance under dynamic conditions plays an important role in determining deviations from equilibrium behavior. Two general types of composite microstructure electrodes, those with a mixed-conducting matrix, and those with a solid electrolyte matrix, are discussed. The Li-Sn-Si system at elevated temperatures, and the Li-Sn-Cd at ambient temperatures are shown to be examples of mixed-conducting matrix microstructures. The convertible oxides are an example of the solid electrolyte matrix type. Although the reversible capacity can be very large in this case, the first cycle irreversible capacity required to convert the oxides to alloys may be a significant handicap.

  20. Lithium thionyl chloride battery

    Energy Technology Data Exchange (ETDEWEB)

    Saathoff, D.J.; Venkatasetty, H.V.

    1982-10-19

    The discharge rate and internal conductivity of electrochemical cell including a lithium anode, and a cathode and an electrolyte including LiAlCl4 and SOC2 is improved by the addition of an amount of a mixture containing AlCl3 and butyl pyridinium chloride.

  1. Synthesis of lithium ceramics

    International Nuclear Information System (INIS)

    Cruz G, D.; Bulbulian, S.

    2001-01-01

    In this work, lithium silicates were synthesised by the combustion technique, the mixtures were prepared with different molar ratios and using urea as fuel. Its characterization was realized by means of X-ray diffraction (XRD) and the percentages of its sizes were determined measuring the area under curve of the peaks in the diffractogram. (Author)

  2. IFMIF-CDA technical workshop on lithium target system. Proceedings

    International Nuclear Information System (INIS)

    1995-09-01

    An intense neutron source, International Fusion Materials Irradiation Facility (IFMIF) is planned under the collaborative program by International Energy Agency (IEA), and the Conceptual Design Activity (CDA) started in February 1995. US, Japan and EU are responsible to take a lead in coordinating accelerator, target and test cell design, respectively. In order to exchange the current results of the study and to coordinate the activities for the design integration, the first technical workshop on the lithium target system was held in the period of July 18-21 at the Tokai Research Establishment of the JAERI. This publication summarizes the materials presented in this meeting. The presentations and discussions were organized with the identified CDA tasks. It was confirmed that the reference design of the IFMIF target based on the previous studies under FMIT and ESNIT, elaborated to meet IFMIF parameters, is reasonable and feasible. It was pointed out that the interface between accelerator and test cell subsystems should be carefully investigated to avoid technical conflicts. Some design options such as nozzle, backwall and lithium jet geometry, lithium purity control, and lithium vapor control, based on the current technology were proposed to improve the integral target system function, and further R and D studies were suggested for design integration. (author)

  3. Press forging and optical properties of lithium fluoride

    Science.gov (United States)

    Ready, J. F.; Vora, H.

    1980-07-01

    Lithium fluoride is an important candidate material for windows on high power, short-pulse ultraviolet and visible lasers. Lithium fluoride crystals were press forged in one step over the temperature range 300 to 600 C to obtain fine grained polycrystalline material with improved mechanical properties. The deformation that can be given to a lithium fluoride crystal during forging is limited by the formation of internal cloudiness (veiling) with the deformation limit increasing with increasing forging temperature from about 40 percent at 400 C to 65 percent at 600 C. To suppress veiling, lithium fluoride crystals were forged in two steps over the temperature range 300 to 600 C, to total deformations of 69 to 76 percent, with intermediate annealing at 700 C. This technique yields a material which has lower scattering with more homogeneous microstructure than that obtained in one step forging. The results of characterization of various optical and mechanical properties of single crystal and forged lithium fluoride, including scattering, optical homogeneity, residual absorption, damage thresholds, environmental stability, and thresholds for microyield are described.

  4. Press forging and optical properties of lithium fluoride

    International Nuclear Information System (INIS)

    Ready, J.F.; Vora, H.

    1979-01-01

    Lithium fluoride is an important candidate material for windows on high-power, short-pulse ultraviolet and visible lasers. Lithium fluoride crystals have been press forged in one step over the temperature range 300 to 600 0 c to obtain fine-grained polycrystalline material with improved mechanical properties. The deformation that can be given to a lithium fluoride crystal during forging is limited by the formation of internal cloudiness (veiling) with the deformation limit increasing with increasing forging temperature from about 40% at 400 0 C to 65% at 600 0 C. To suppress veiling, lithium fluoride crystals were forged in two steps over the temperature range 300 to 600 0 C, to total deformations of 69-76%, with intermediate annealing at 700 0 C. This technique yields a material which has lower scattering with more homogeneous microstructure than that obtained in one-step forging. The results of characterization of various optical and mechanical properties of single-crystal and forged lithium fluoride, including scattering, optical homogeneity, residual absorption, damage thresholds, environmental stability, and thresholds for microyield are described

  5. Solubility of lithium deuteride in liquid lithium

    International Nuclear Information System (INIS)

    Veleckis, E.; Yonco, R.M.; Maroni, V.A.

    1977-01-01

    The solubility of LiD in liquid lithium between the eutectic and monotectic temperatures was measured using a direct sampling method. Solubilities were found to range from 0.0154 mol.% LiD at 199 0 C to 3.32 mol.% LiD at 498 0 C. The data were used in the derivation of an expression for the activity coefficient of LiD as a function of temperature and composition and an equation relating deuteride solubility and temperature, thus defining the liquidus curve. Similar equations were also derived for the Li-LiH system using the existing solubility data. Extrapolation of the liquidus curves yielded the eutectic concentrations (0.040 mol.% LiH and 0.035 mol.% LiD) and the freezing point depressions (0.23 0 C for Li-LiH and 0.20 0 C for Li-LiD) at the eutectic point. The results are compared with the literature data for hydrogen and deuterium. The implications of the relatively high solubility of hydrogen isotopes in lithium just above the melting point are discussed with respect to the cold trapping of tritium in fusion reactor blankets. (Auth.)

  6. Sixteenth International Laser Radar Conference, Part 2

    International Nuclear Information System (INIS)

    Mccormick, M.P.

    1992-07-01

    Given here are extended abstracts of papers presented at the 16th International Laser Radar Conference, held in Cambridge, Massachusetts, July 20-24, 1992. Topics discussed include the Mt. Pinatubo volcanic dust laser observations, global change, ozone measurements, Earth mesospheric measurements, wind measurements, imaging, ranging, water vapor measurements, and laser devices and technology

  7. Vapor pressure and enthalpy of vaporization of linear aliphatic alkanediamines

    International Nuclear Information System (INIS)

    Pozdeev, Vasiliy A.; Verevkin, Sergey P.

    2011-01-01

    Highlights: → We measured vapor pressure of diamines H 2 N-(CH 2 ) n -NH 2 with n = 3 to 12. → Vaporization enthalpies at 298 K were derived. → We examined consistency of new and available in the literature data. → Enthalpies of vaporization show linear dependence on numbers n. → Enthalpies of vaporization correlate linearly with Kovat's indices. - Abstract: Vapor pressures and the molar enthalpies of vaporization of the linear aliphatic alkanediamines H 2 N-(CH 2 ) n -NH 2 with n = (3 to 12) have been determined using the transpiration method. A linear correlation of enthalpies of vaporization (at T = 298.15 K) of the alkanediamines with the number n and with the Kovat's indices has been found, proving the internal consistency of the measured data.

  8. Approach to lithium burn-up effect in lithium ceramics

    International Nuclear Information System (INIS)

    Rasneur, B.

    1994-01-01

    The lithium burn-up in Li 2 ZrO 3 is simulated by removing lithium under Li 2 O form and trapping it in high specific surface area powder while heating during 15 days or 1 month at moderate temperature so that lithium mobility be large enough without causing any sintering neither of the specimens nor of the powder. In a first treatment at 775 deg C during 1 month. 30% of the lithium content could be removed inducing a lithium concentration gradient in the specimen and the formation of a lithium-free monoclinic ZrO 2 skin. Improvements led to similar results at 650 deg C and 600 deg C, the latter temperatures are closer to the operating temperature of the ceramic breeder blanket of a fusion reactor. (author) 4 refs.; 4 figs.; 1 tab

  9. Growth and decomposition of Lithium and Lithium hydride on Nickel

    DEFF Research Database (Denmark)

    Engbæk, Jakob; Nielsen, Gunver; Nielsen, Jane Hvolbæk

    2006-01-01

    In this paper we have investigated the deposition, structure and decomposition of lithium and lithium-hydride films on a nickel substrate. Using surface sensitive techniques it was possible to quantify the deposited Li amount, and to optimize the deposition procedure for synthesizing lithium......-hydride films. By only making thin films of LiH it is possible to study the stability of these hydride layers and compare it directly with the stability of pure Li without having any transport phenomena or adsorbed oxygen to obscure the results. The desorption of metallic lithium takes place at a lower...... temperature than the decomposition of the lithium-hydride, confirming the high stability and sintering problems of lithium-hydride making the storage potential a challenge. (c) 2006 Elsevier B.V. All rights reserved....

  10. Anomalous Lithium Adsorption Propensity of Monolayer ...

    Indian Academy of Sciences (India)

    longer life cycle, thus an ideal candidate to replace the conventional ... tion in the development of lithium ion batteries as they ... interaction of graphene with lithium based on density ... aromatic hydrocarbons.30 Lithium doping increases.

  11. Development of an Airborne Micropulse Water Vapor DIAL

    Science.gov (United States)

    Nehrir, A. R.; Ismail, S.

    2012-12-01

    Water vapor plays a key role in many atmospheric processes affecting both weather and climate. Airborne measurements of tropospheric water vapor profiles have been a longstanding observational need to not only the active remote sensing community but also to the meteorological, weather forecasting, and climate/radiation science communities. Microscale measurements of tropospheric water vapor are important for enhancing near term meteorological forecasting capabilities while mesoscale and synopticscale measurements can lead to an enhanced understanding of the complex coupled feedback mechanisms between water vapor, temperature, aerosols, and clouds. To realize tropospheric measurements of water vapor profiles over the microscale-synopticscale areas of meteorological interest, a compact and cost effective airborne micropulse differential absorption lidar (DIAL) is being investigated using newly emerging semiconductor based laser technology. Ground based micropulse DIAL (MPD) measurements of tropospheric water vapor and aerosol profiles up to 6 km and 15 km, respectively, have been previously demonstrated using an all semiconductor based laser transmitter. The DIAL transmitter utilizes a master oscillator power amplifier (MOPA) configuration where two semiconductor seed lasers are used to seed a single pass traveling wave tapered semiconductor optical amplifier (TSOA), producing up to 7μJ pulse energies over a 1 μs pulse duration at a 10 kHz pulse repetition frequency (PRF). Intercomparisons between the ground based instrument measurements and radiosonde profiles demonstrating the MPD performance under varying atmospheric conditions will be presented. Work is currently ongoing to expand upon the ground based MPD concept and to develop a compact and cost effective system capable of deployment on a mid-low altitude aircraft such as the NASA Langley B200 King Air. Initial lab experiments show that a two-three fold increase in the laser energy compared to the ground

  12. Constrained Vapor Bubble Experiment

    Science.gov (United States)

    Gokhale, Shripad; Plawsky, Joel; Wayner, Peter C., Jr.; Zheng, Ling; Wang, Ying-Xi

    2002-11-01

    Microgravity experiments on the Constrained Vapor Bubble Heat Exchanger, CVB, are being developed for the International Space Station. In particular, we present results of a precursory experimental and theoretical study of the vertical Constrained Vapor Bubble in the Earth's environment. A novel non-isothermal experimental setup was designed and built to study the transport processes in an ethanol/quartz vertical CVB system. Temperature profiles were measured using an in situ PC (personal computer)-based LabView data acquisition system via thermocouples. Film thickness profiles were measured using interferometry. A theoretical model was developed to predict the curvature profile of the stable film in the evaporator. The concept of the total amount of evaporation, which can be obtained directly by integrating the experimental temperature profile, was introduced. Experimentally measured curvature profiles are in good agreement with modeling results. For microgravity conditions, an analytical expression, which reveals an inherent relation between temperature and curvature profiles, was derived.

  13. Method of producing spherical lithium aluminate particles

    International Nuclear Information System (INIS)

    Yang, L.; Medico, R.R.; Baugh, W.A.

    1983-01-01

    Spherical particles of lithium aluminate are formed by initially producing aluminium hydroxide spheroids, and immersing the spheroids in a lithium ion-containing solution to infuse lithium ions into the spheroids. The lithium-infused spheroids are rinsed to remove excess lithium ion from the surface, and the rinsed spheroids are soaked for a period of time in a liquid medium, dried and sintered to form lithium aluminate spherical particles. (author)

  14. Process for recovery of lithium from spent lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Kunugita, Eiichi; Jonghwa, Kim; Komasawa, Isao [Osaka Univ., Faculty of Engineering Science, Osaka, (Japan)

    1989-07-10

    An experimental study of the recovery and purification of lithium from spent lithium batteries was carried out, taking advantage of the characterisitics of lithium ion and its carbonate. More than 75% of the lithium contained in the whole battery or its anode component can be leached with sulfuric acid where the pH of the final pregnant liquor is 7.7 or higher, the other metals being left in the residue is their hydroxides. The extracted liquor is evaporated/concentrated, added with saturated sodium carbonate solution at around 100{sup 0}C to precipitate lithium as a carbonate. The coprecipitated sodium carbonate is washed/removed with a hotwater to give 99% pure lithium carbonate. Separation of lithium and sodium in the barren liquor is conducted with LIX 51, a chelating/extracting agent, and TOPO, a neutral organic phosphate, which have a synergic effect, to selectively extract lithium; the organic phase is reverse-extracted with a dilute hydrochloric acid to obtain lithium of 99% purity. 9 refs., 4 figs., 5 tabs.

  15. Vapor condensation device

    International Nuclear Information System (INIS)

    Sakurai, Manabu; Hirayama, Fumio; Kurosawa, Setsumi; Yoshikawa, Jun; Hosaka, Seiichi.

    1992-01-01

    The present invention enables to separate and remove 14 C as CO 3 - ions without condensation in a vapor condensation can of a nuclear facility. That is, the vapor condensation device of the nuclear facility comprises (1) a spray pipe for spraying an acidic aqueous solution to the evaporation surface of an evaporation section, (2) a spray pump for sending the acidic aqueous solution to the spray pipe, (3) a tank for storing the acidic aqueous solution, (4) a pH sensor for detecting pH of the evaporation section, (5) a pH control section for controlling the spray pump, depending on the result of the detection of the pH sensor. With such a constitution, the pH of liquid wastes on the vaporization surface is controlled to 7 by spraying an aqueous solution of dilute sulfuric acid to the evaporation surface, thereby enabling to increase the transfer rate of 14 C to condensates to 60 to 70%. If 14 C is separated and removed as a CO 2 gas from the evaporation surface, the pH of the liquid wastes returns to the alkaline range of 9 to 10 and the liquid wastes are returned to a heating section. The amount of spraying the aqueous solution of dilute sulfuric acid can be controlled till the pH is reduced to 5. (I.S.)

  16. The vapor pressures of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Ewing, Robert G.; Waltman, Melanie J.; Atkinson, David A.; Grate, Jay W.; Hotchkiss, Peter

    2013-01-05

    The vapor pressures of many explosive compounds are extremely low and thus determining accurate values proves difficult. Many researchers, using a variety of methods, have measured and reported the vapor pressures of explosives compounds at single temperatures, or as a function of temperature using vapor pressure equations. There are large variations in reported vapor pressures for many of these compounds, and some errors exist within individual papers. This article provides a review of explosive vapor pressures and describes the methods used to determine them. We have compiled primary vapor pressure relationships traceable to the original citations and include the temperature ranges for which they have been determined. Corrected values are reported as needed and described in the text. In addition, after critically examining the available data, we calculate and tabulate vapor pressures at 25 °C.

  17. Lithium clearance in chronic nephropathy

    DEFF Research Database (Denmark)

    Kamper, A L; Holstein-Rathlou, N H; Leyssac, P P

    1989-01-01

    1. Lithium clearance measurements were made in 72 patients with chronic nephropathy of different aetiology and moderate to severely reduced renal function. 2. Lithium clearance was strictly correlated with glomerular filtration rate, and there was no suggestion of distal tubular reabsorption...... of lithium or influence of osmotic diuresis. 3. Fractional reabsorption of lithium was reduced in most patients with glomerular filtration rates below 25 ml/min. 4. Calculated fractional distal reabsorption of sodium was reduced in most patients with glomerular filtration rates below 50 ml/min. 5. Lithium...... that lithium clearance may be a measure of the delivery of sodium and water from the renal proximal tubule. With this assumption it was found that adjustment of the sodium excretion in chronic nephropathy initially takes place in the distal parts of the nephron (loop of Henle, distal tubule and collecting duct...

  18. Lasers: present and future research

    International Nuclear Information System (INIS)

    Philippe, P.

    1981-01-01

    Recent advances in the field of lasers are reviewed in particular in the French laboratories. Different lasers are briefly described related to their applications: rare gas halide, iodine, metal vapor, color center, transition-metal solid state, CO 2 , chemical, blue-green and free electron lasers. Among applications researches on thermonuclear fusion are given p. 125 and researches concerning isotope separation are given p. 126 and 127 [fr

  19. Erbium ion implantation into different crystallographic cuts of lithium niobate

    Czech Academy of Sciences Publication Activity Database

    Nekvindová, P.; Švecová, B.; Cajzl, J.; Macková, Anna; Malinský, Petr; Oswald, Jiří; Kolitsch, A.; Špirková, J.

    2012-01-01

    Roč. 34, č. 4 (2012), s. 652-659 ISSN 0925-3467 R&D Projects: GA MŠk(CZ) LC06041; GA ČR GA106/09/0125; GA ČR(CZ) GAP106/10/1477 Institutional research plan: CEZ:AV0Z10480505; CEZ:AV0Z10100521 Keywords : Lithium niobate * Erbium * Ion implantation * Luminescence Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.918, year: 2012

  20. Investigation on orientation, epitaxial growth and microstructure of a-axis-, c-axis-, (103)/(110)- and (113)-oriented YBa2Cu3O7-δ films prepared on (001), (110) and (111) SrTiO3 single crystal substrates by spray atomizing and coprecipitating laser chemical vapor deposition

    Science.gov (United States)

    Zhao, Pei; Wang, Ying; Huang, Zhi liang; Mao, Yangwu; Xu, Yuan Lai

    2015-04-01

    a-axis-, c-axis-, (103)/(110)- and (113)-oriented YBa2Cu3O7-δ (YBCO) films were pareared by spray atomizing and coprecipitating laser chemical vapor deposition. The surface of the a-axis-oriented YBCO film consisted of rectangular needle-like grains whose in-plane epitaxial growth relationship was YBCO [100] // STO [001] (YBCO [001] // STO [100]), and that of the c-axis-oriented YBCO film consisted of dense flat surface with epitaxial growth relationship of YBCO [001] // STO [001] (YBCO [100] //STO [100]). For the (103)/(110)-oriented and (113)-oriented YBCO film, they showed wedge-shaped and triangle-shaped grains, with corresponding in-plane epitaxial growth relationship of YBCO [110] // STO [110] (YBCO [010] // STO [010]) and YBCO [100] // STO [100] (YBCO [113] // STO [111], respectively.

  1. Physical Vapor Deposition of Thin Films

    Science.gov (United States)

    Mahan, John E.

    2000-01-01

    A unified treatment of the theories, data, and technologies underlying physical vapor deposition methods With electronic, optical, and magnetic coating technologies increasingly dominating manufacturing in the high-tech industries, there is a growing need for expertise in physical vapor deposition of thin films. This important new work provides researchers and engineers in this field with the information they need to tackle thin film processes in the real world. Presenting a cohesive, thoroughly developed treatment of both fundamental and applied topics, Physical Vapor Deposition of Thin Films incorporates many critical results from across the literature as it imparts a working knowledge of a variety of present-day techniques. Numerous worked examples, extensive references, and more than 100 illustrations and photographs accompany coverage of: * Thermal evaporation, sputtering, and pulsed laser deposition techniques * Key theories and phenomena, including the kinetic theory of gases, adsorption and condensation, high-vacuum pumping dynamics, and sputtering discharges * Trends in sputter yield data and a new simplified collisional model of sputter yield for pure element targets * Quantitative models for film deposition rate, thickness profiles, and thermalization of the sputtered beam

  2. Experimental study of vapor bubble dynamics

    International Nuclear Information System (INIS)

    Pasquini, Maria-Elena

    2015-01-01

    The object of this thesis is an experimental study of vapor bubble dynamics in sub-cooled nucleate boiling. The test section is locally heated by focusing a laser beam: heat fluxes from 1 e4 to 1.5 e6 W/m 2 and water temperature between 100 and 88 C have been considered. Three boiling regimes have been observed. Under saturated conditions and with low heat fluxes a developed nucleate boiling regime has been observed. Under higher sub-cooling and still with low heat fluxes an equilibrium regime has been observed in which the liquid flowrate evaporating at the bubble base is compensated by the vapor condensing flowrate at bubble top. A third regime have been observed at high heat fluxes for all water conditions: it is characterized by the formation of a large dry spot on the heated surface that keeps the nucleation site dry after bubble detachment. The condensation phase starts after bubble detachment. Bubble equivalent radius at detachment varies between 1 and 2.5 mm. Bubble properties have been measured and non-dimensional groups have been used to characterize bubble dynamics. Capillary waves have been observed on the bubble surface thanks to high-speed images acquisition. Two main phenomena have been proposed to explain capillary waves effects on bubble condensation: increasing of the phases interface area and decreasing of vapor bubble translation velocity, because of the increased drag force on the deformed bubble. (author) [fr

  3. High-power frequency-stabilized laser for laser cooling of metastable helium at 389 nm

    NARCIS (Netherlands)

    Koelemeij, J.C.J.; Hogervorst, W.; Vassen, W.

    2005-01-01

    A high-power, frequency-stabilized laser for cooling of metastable helium atoms using the 2 S13 →3 P23 transition at 389 nm has been developed. The 389 nm light is generated by frequency doubling of a titanium:sapphire laser in an external enhancement cavity containing a lithium-triborate nonlinear

  4. VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS

    Energy Technology Data Exchange (ETDEWEB)

    Eric M. Suuberg; Vahur Oja

    1997-07-01

    This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization which have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.

  5. Membranes in Lithium Ion Batteries

    Science.gov (United States)

    Yang, Min; Hou, Junbo

    2012-01-01

    Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed. PMID:24958286

  6. Membranes in Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Junbo Hou

    2012-07-01

    Full Text Available Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed.

  7. Effect of sweep gas chemistry on vaporization of Li4SiO4

    International Nuclear Information System (INIS)

    Yamawaki, M.; Yamaguchi, K.

    1995-01-01

    Gas/solid equilibria in the system Li 4 SiO 4 -D 2 -D 2 O were studied by means of Knudsen effusion mass spectrometry. A Knudsen effusion mass spectrometer was modified to enable studies of reactions of hydrogen and/or water vapor with ceramic breeder materials. A gas inlet system was constructed to allow the introduction of gases into a platinum Knudsen cell, from which the equilibrated gaseous reaction products effuse. From the experimental results, it has been deduced that the equilibrium constants of vaporization reactions differ correspondingly to the nonstoichiometry of lithium orthosilicate. ((orig.))

  8. Lasers and uranium isotope separation

    Energy Technology Data Exchange (ETDEWEB)

    Gilles, L

    1987-12-01

    The use of lasers by the electronuclear industry to enrich uranium is discussed, particularly economic aspects. The SILMO and SILVA processes (chosen by France for industrial development) are presented. Criteria which lead to the choice of lasers and to their set-up (architecture of the chain) are described. For electricity - consumption linked to the use of lasers of 40 kWh/STU, a laser uranium enrichment plant with 10 STU/yr capacity requires 50kW of light from copper vapor lasers, i.e., 500 units each having 100W capacity, compared with the 40W units currently marketed.

  9. LEVIS lithium ion source experiments on PBFA-II

    International Nuclear Information System (INIS)

    Renk, T.J.; Tisone, G.C.; Adams, R.G.; Lopez, M.; Clark, B.F.; Schroeder, J.; Bailey, J.E.; Filuk, A.B.; Carlson, A.L.

    1992-01-01

    PBFA-II is a pulsed power generator designed to apply up to a 25 MV, 20 ns pulse to a focusing 15 cm-radius Applied-B ion diode for inertial confinement fusion applications. Several different approaches have been pursued to produce a high-purity (> 90%), high-current density (5--10 kA/cm 2 ) singly ionized lithium ion source for acceleration in this diode. In addition to having high source purity, such a source should be active, i.e. the ions should be produced before the power pulse arrives, to provide better electrical coupling from the accelerator to the diode. In the LEVIS (Laser EVaporation Ion Source) process, energy from two lasers impinges on a thin (500 nm) lithium or lithium-bearing film on an insulating substrate. The authors will discuss a new series of LEVIS experiments, with a number of improvements: (1) the laser distribution cone was redesigned, resulting in a more uniform illumination of the 4 cm-tall Li-producing surface; (2) the anode surface is being slow-heated to 120--150 C to help drive off contaminants; and (3) they have expanded the number of source and beam diagnostics

  10. Recovery of lithium from seawater

    International Nuclear Information System (INIS)

    Ooi, Kenta; Miyai, Yoshitaka; Katoh, Shunsaku; Abe, Mitsuo.

    1989-01-01

    Lithium has been used for air conditioners, aluminum refining, ceramics, organic metal compounds, batteries and many other uses. Besides, attention is paid as the aluminum-lithium alloys as aircraft materials, and the raw materials for large capacity batteries and nuclear fusion reactors for the future. The amount of lithium resources has been estimated as 14 million tons, and is relatively abundant, but when the future increase of demand is considered, it is not necessarily sufficient. Japan lacks lithium resources, and the stable ensuring of the resources has become an important problem. Seawater contains lithium by 170 μg/l, and its total amount reaches 230 billion tons. The process of recovering lithium from seawater, geothermal water and natural gas brine has been actively researched since 10 years ago centering around Japan. At present, the search for the adsorbent that effectively collects lithium is the main subject. Also the recovery by coprecipitation has been investigated basically. The inorganic adsorbent for lithium is classified into aluminum type, compound antimonic acid type, layered compound type, ion sieve oxide type and others. Their lithium adsorption performance and adsorption mechanism are different remarkably, therefore, these of each group are described. (K.I.) 70 refs

  11. Low cost, high yield IFE reactors: Revisiting Velikhov's vaporizing blankets

    International Nuclear Information System (INIS)

    Logan, B.G.

    1992-01-01

    The performance (efficiency and cost) of IFE reactors using MHD conversion is explored for target blanket shells of various materials vaporized and ionized by high fusion yields (5 to 500 GJ). A magnetized, prestressed reactor chamber concept is modeled together with previously developed models for the Compact Fusion Advanced Rankine II (CFARII) MHD Balance-of-Plant (BoP). Using conservative 1-D neutronics models, high fusion yields (20 to 80 GJ) are found necessary to heat Flibe, lithium, and lead-lithium blankets to MHD plasma temperatures, at initial solid thicknesses sufficient to capture most of the fusion yield. Advanced drivers/targets would need to be developed to achieve a ''Bang per Buck'' figure-of-merit approx-gt 20 to 40 joules yield per driver $ for this scheme to be competitive with these blanket materials. Alternatively, more realistic neutronics models and better materials such as lithium hydride may lower the minimum required yields substantially. The very low CFARII BoP costs (contributing only 3 mills/kWehr to CoE) allows this type of reactor, given sufficient advances that non-driver costs dominate, to ultimately produce electricity at a much lower cost than any current nuclear plant

  12. An overview of copper-laser development for isotope separation

    International Nuclear Information System (INIS)

    Warner, B.E.

    1987-01-01

    We have developed a copper-laser pumped dye-laser system that addresses all of the requirements for atomic vapor laser isotope separation. The requirement for high average power for the laser system has led to the development of copper-laser chains with injection-locked oscillators and multihundred-watt amplifiers. By continuously operating the Laser Demonstration Facility, we gain valuable data for further upgrade and optimization

  13. Lithium reserves and resources

    International Nuclear Information System (INIS)

    Evans, R.K.

    1978-01-01

    As a result of accelerating research efforts in the fields of secondary batteries and thermonuclear power generation, concern has been expressed in certain quarters regarding the availability, in sufficient quantities, of lithium. As part of a recent study by the National Research Council on behalf of the Energy Research and Development Administration, a subpanel was formed to consider the outlook for lithium. Principal areas of concern were reserves, resources and the 'surplus' available for energy applications after allowing for the growth in current lithium applications. Reserves and resources were categorized into four classes ranging from fully proved reserves to resources which are probably dependent upon the marketing of co-products to become economically attractive. Because of the proprietary nature of data on beneficiation and processing recoveries, the tonnages of available lithium are expressed in terms of plant feed. However, highly conservative assumptions have been made concerning mining recoveries and these go a considerable way to accounting for total losses. Western World reserves and resources of all classes are estimated at 10.6 million tonnes Li of which 3.5 million tonnes Li are located in the United States. Current United States capacity, virtually equivalent to Western World capacity, is 4700 tonnes Li and production in 1976 approximated to 3500 tonnes Li. Production for current applications is expected to grow to approx. 10,000 tonnes in year 2000 and 13,000 tonnes a decade later. The massive excess of reserves and resources over that necessary to support conventional requirements has limited the amount of justifiable exploration expenditures; on the last occasion, there was a a major increase in demand (by the USAEA) reserves and capacity were increased rapidly. There are no foreseeable reasons why this shouldn't happen again when the need is clear. (author)

  14. Advanced lasers for fusion

    International Nuclear Information System (INIS)

    Krupke, W.F.; George, E.V.; Haas, R.A.

    1979-01-01

    Laser drive systems' performance requirements for fusion reactors are developed following a review of the principles of inertial confinement fusion and of the technical status of fusion research lasers (Nd:glass; CO 2 , iodine). These requirements are analyzed in the context of energy-storing laser media with respect to laser systems design issues: optical damage and breakdown, medium excitation, parasitics and superfluorescence depumping, energy extraction physics, medium optical quality, and gas flow. Three types of energy-storing laser media of potential utility are identified and singled out for detailed review: (1) Group VI atomic lasers, (2) rare earth solid state hybrid lasers, and (3) rare earth molecular vapor lasers. The use of highly-radiative laser media, particularly the rare-gas monohalide excimers, are discussed in the context of short pulse fusion applications. The concept of backward wave Raman pulse compression is considered as an attractive technique for this purpose. The basic physics and device parameters of these four laser systems are reviewed and conceptual designs for high energy laser systems are presented. Preliminary estimates for systems efficiencies are given. (Auth.)

  15. Fatigue crack propagation in aluminum-lithium alloys

    Science.gov (United States)

    Rao, K. T. V.; Ritchie, R. O.; Piascik, R. S.; Gangloff, R. P.

    1989-01-01

    The principal mechanisms which govern the fatigue crack propagation resistance of aluminum-lithium alloys are investigated, with emphasis on their behavior in controlled gaseous and aqueous environments. Extensive data describe the growth kinetics of fatigue cracks in ingot metallurgy Al-Li alloys 2090, 2091, 8090, and 8091 and in powder metallurgy alloys exposed to moist air. Results are compared with data for traditional aluminum alloys 2024, 2124, 2618, 7075, and 7150. Crack growth is found to be dominated by shielding from tortuous crack paths and resultant asperity wedging. Beneficial shielding is minimized for small cracks, for high stress ratios, and for certain loading spectra. While water vapor and aqueous chloride environments enhance crack propagation, Al-Li-Cu alloys behave similarly to 2000-series aluminum alloys. Cracking in water vapor is controlled by hydrogen embrittlement, with surface films having little influence on cyclic plasticity.

  16. The testing report of the development for the lithium grains and lithium rod automatic machine

    International Nuclear Information System (INIS)

    Qian Zongkui; Kong Xianghong; Huang Yong

    2008-06-01

    With the development of lithium industry, the lithium grains and lithium rod, as additive or catalyzer, having a big comparatively acreage and a strong activated feature, have a broad application. The lithium grains and lithium rod belong to the kind of final machining materials. The principle of the lithium grains and lithium rod that how to take shape through the procedures of extrusion, cutting, anti-conglutination, threshing and so on are analysed, A sort of lithium grains and lithium rod automatic machine is developed. (authors)

  17. IR Laser-Induced Co-decomposition of Dimethyl Selenide and Trisilane: Gas-Phase Formation of SiSe and Chemical Vapor Deposition of Nanostructured H/Si/Se/C Polymers.

    Czech Academy of Sciences Publication Activity Database

    Santos, M.; Díaz, L.; Urbanová, Markéta; Bastl, Zdeněk; Šubrt, Jan; Pola, Josef

    2007-01-01

    Roč. 188, 2-3 (2007) , s. 399-408 ISSN 1010-6030 R&D Projects: GA MŠk(CZ) ME 846 Grant - others:MCyT(ES) BQU2003/08531/C02/02 Institutional research plan: CEZ:AV0Z40720504; CEZ:AV0Z40320502; CEZ:AV0Z40400503 Keywords : laser deposition * laser-induced polymers * silicon selenide Subject RIV: CH - Nuclear ; Quantum Chemistry Impact factor: 1.911, year: 2007

  18. A study on vapor explosions

    International Nuclear Information System (INIS)

    Takagi, N.; Shoji, M.

    1979-01-01

    An experimental study was carried out for vapor explosions of molten tin falling in water. For various initial metal temperatures and subcooling of water, transient pressure of the explosions, relative frequency of the explosions and the position where the explosions occur were measured in detail. The influence of ambient pressure was also investigated. From the results, it was concluded that the vapor explosion is closely related to the collapse of a vapor film around the molten metal. (author)

  19. Selective gas sensing for photonic crystal lasers

    DEFF Research Database (Denmark)

    Smith, Cameron; Christiansen, Mads Brøkner; Buss, Thomas

    2011-01-01

    We facilitate photonic crystal lasers to sense gases via an additional swelling polymer film. We describe the transduction transfer function and experimentally demonstrate an enhanced ethanol vapor sensitivity over 15 dB with low humidity crosstalk.......We facilitate photonic crystal lasers to sense gases via an additional swelling polymer film. We describe the transduction transfer function and experimentally demonstrate an enhanced ethanol vapor sensitivity over 15 dB with low humidity crosstalk....

  20. Mass spectrometric analysis of lithium

    International Nuclear Information System (INIS)

    Chitambar, S.A.; Kavimandan, V.D.; Aggarwal, S.K.; Ramasubramanian, P.A.; Shah, P.M.; Almoula, A.I.; Acharya, S.N.; Parab, A.R.; Jain, H.C.; Mathews, C.K.; Ramaniah, M.V.

    1978-01-01

    The details of investigations carried out on the isotopic analysis of lithium using surface ionisation mass spectrometry are presented. Various parameters affecting the precision in isotopic analysis of lithium are discussed. A precision of 1% is achieved in the relative isotope abundance measurement. (author)

  1. Nuclear system vaporization

    International Nuclear Information System (INIS)

    Bougault, R.; Brou, R.; Colin, J.; Cussol, D.; Durand, D.; Le Brun, C.; Lecolley, J.F.; Lopez, O.; Louvel, M.; Nakagawa, T.; Peter, J.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Yuasa-Nakagawa, K.; Wieloch, A.

    1998-01-01

    A particular case of the hot nuclei de-excitation is the total nuclear dislocation into light particles (n, p, d, t, 3 He and α). Such events were first observed at bombarding energies lower than 100 MeV/nucleon due to high detection performances of the INDRA multidetector. The light system Ar + Ni was studied at several bombarding energies ranging from 32 to 95 MeV/nucleon. The events associated to a total vaporization of the system occur above the energy threshold of ∼ 50 MeV/nucleon. A study of the form of these events shows that we have essentially two sources. The excitation energy of these sources may be determined by means of the kinematic properties of their de-excitation products. A preliminary study results in excitation energy values of the order 10 - 14 MeV/nucleon. The theoretical calculation based on a statistical model modified to take into account high excitation energies and excited levels in the lightest nuclei predicts that the vaporization of the two partner nuclei in the Ar + Ni system takes place when the excitation energy exceeds 12 MeV/nucleon what is qualitatively in agreement with the values deduced from calorimetric analysis

  2. Evidence of ion intercalation mediated band structure modification and opto-ionic coupling in lithium niobite

    Science.gov (United States)

    Shank, Joshua C.; Tellekamp, M. Brooks; Doolittle, W. Alan

    2015-01-01

    The theoretically suggested band structure of the novel p-type semiconductor lithium niobite (LiNbO2), the direct coupling of photons to ion motion, and optically induced band structure modifications are investigated by temperature dependent photoluminescence. LiNbO2 has previously been used as a memristor material but is shown here to be useful as a sensor owing to the electrical, optical, and chemical ease of lithium removal and insertion. Despite the high concentration of vacancies present in lithium niobite due to the intentional removal of lithium atoms, strong photoluminescence spectra are observed even at room temperature that experimentally confirm the suggested band structure implying transitions from a flat conduction band to a degenerate valence band. Removal of small amounts of lithium significantly modifies the photoluminescence spectra including additional larger than stoichiometric-band gap features. Sufficient removal of lithium results in the elimination of the photoluminescence response supporting the predicted transition from a direct to indirect band gap semiconductor. In addition, non-thermal coupling between the incident laser and lithium ions is observed and results in modulation of the electrical impedance.

  3. Evidence of ion intercalation mediated band structure modification and opto-ionic coupling in lithium niobite

    Energy Technology Data Exchange (ETDEWEB)

    Shank, Joshua C.; Tellekamp, M. Brooks; Doolittle, W. Alan, E-mail: alan.doolittle@ece.gatech.edu [Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2015-01-21

    The theoretically suggested band structure of the novel p-type semiconductor lithium niobite (LiNbO{sub 2}), the direct coupling of photons to ion motion, and optically induced band structure modifications are investigated by temperature dependent photoluminescence. LiNbO{sub 2} has previously been used as a memristor material but is shown here to be useful as a sensor owing to the electrical, optical, and chemical ease of lithium removal and insertion. Despite the high concentration of vacancies present in lithium niobite due to the intentional removal of lithium atoms, strong photoluminescence spectra are observed even at room temperature that experimentally confirm the suggested band structure implying transitions from a flat conduction band to a degenerate valence band. Removal of small amounts of lithium significantly modifies the photoluminescence spectra including additional larger than stoichiometric-band gap features. Sufficient removal of lithium results in the elimination of the photoluminescence response supporting the predicted transition from a direct to indirect band gap semiconductor. In addition, non-thermal coupling between the incident laser and lithium ions is observed and results in modulation of the electrical impedance.

  4. Evidence of ion intercalation mediated band structure modification and opto-ionic coupling in lithium niobite

    International Nuclear Information System (INIS)

    Shank, Joshua C.; Tellekamp, M. Brooks; Doolittle, W. Alan

    2015-01-01

    The theoretically suggested band structure of the novel p-type semiconductor lithium niobite (LiNbO 2 ), the direct coupling of photons to ion motion, and optically induced band structure modifications are investigated by temperature dependent photoluminescence. LiNbO 2 has previously been used as a memristor material but is shown here to be useful as a sensor owing to the electrical, optical, and chemical ease of lithium removal and insertion. Despite the high concentration of vacancies present in lithium niobite due to the intentional removal of lithium atoms, strong photoluminescence spectra are observed even at room temperature that experimentally confirm the suggested band structure implying transitions from a flat conduction band to a degenerate valence band. Removal of small amounts of lithium significantly modifies the photoluminescence spectra including additional larger than stoichiometric-band gap features. Sufficient removal of lithium results in the elimination of the photoluminescence response supporting the predicted transition from a direct to indirect band gap semiconductor. In addition, non-thermal coupling between the incident laser and lithium ions is observed and results in modulation of the electrical impedance

  5. Metabolic Side Effects of Lithium

    Directory of Open Access Journals (Sweden)

    M. Cagdas Eker

    2010-04-01

    Full Text Available Lithium is an alkaline ion being used since 19th century. After its widespread use in psychiatric disorders, observed side effects caused skepticism about its therapeutic efficacy. Despite several disadvantages, lithium is one of the indispensible drugs used in affective disorders, especially in bipolar disorder. It became a necessity for physicians to recognize its side effects since lithium is still accepted as a gold standard in the treatment of bipolar disorder. Adverse effects of chronic administration of lithium on several organ systems are widely known. In this article metabolic effects of lithium on thyroid and parathyroid glands, body mass index and kidneys will be discussed along with their mechanisms, clinical findings, possible risk factors and treatment. One of the most common side effect of lithium is hypothyroidism. It has the same clinical and biochemical properties as primary hypothyroidism and observed as subclinical hypothyroidism in the first place. Hypothyroidism, even its subclinical form, may be associated with non-response or inadequate response and is indicated as a risk factor for development of rapid cycling bipolar disorder. Therefore, hypothyroidism should be screened no matter how severe it is and should be treated with thyroid hormone in the presence of clinical hypothyroidism. Weight gain due to lithium administration disturbs the compliance to treatment and negatively affects the course of the illness. Increased risk for diabetes, hypertension, ischemic heart disease and stroke because of weight gain constitute other centers of problem. Indeed, it is of importance to determine the risk factors before treatment, to follow up the weight, to re-organize nutritional habits and to schedule exercises. Another frequent problematic side effect of lithium treatment is renal dysfunction which clinically present as nephrogenic diabetes insipidus with the common symptoms of polyuria and polydipsia. Nephrogenic diabetes

  6. 77 FR 28259 - Mailings of Lithium Batteries

    Science.gov (United States)

    2012-05-14

    ... POSTAL SERVICE 39 CFR Part 111 Mailings of Lithium Batteries AGENCY: Postal Service TM . ACTION... international mailing of lithium batteries and devices containing lithium batteries. This prohibition also extends to the mailing of lithium batteries to and from an APO, FPO, or DPO location. However, this...

  7. Comparison of radiative and structural properties of 1.3 µm InxGa(1-x)As quantum-dot laser structures grown by metalorganic chemical vapor deposition and molecular-beam epitaxy: Effect on the lasing properties

    NARCIS (Netherlands)

    Passaseo, A.; Vittorio, de M.; Todaro, M.T.; Tarantini, I.; Giorgi, de M.; Cingolani, R.; Taurino, A.; Catalano, M.; Fiore, A.; Markus, A.; Chen, J.X.; Paranthoën, C.; Oesterle, U.; Ilegems, M.

    2003-01-01

    The authors have studied the radiative and structural properties of identical InxGa(1-x)As quantum dot laser structures grown by metalorg. CVD (MOCVD) and MBE. Despite the comparable emission properties found in the two devices by photoluminescence, electroluminescence, and photocurrent

  8. Lithium in the barium stars

    International Nuclear Information System (INIS)

    Pinsonneault, M.H.; Sneden, C.

    1984-01-01

    New high-resolution spectra of the lithium resonance doublet have provided lithium abundances or upper limits for 26 classical and mild barium stars. The lithium lines always are present in the classical barium stars. Lithium abundances in these stars obey a trend with stellar masses consistent with that previously derived for ordinary K giants. This supports the notion that classical barium stars are post-core-He-flash or core-He-burning stars. Lithium contents in the mild barium stars, however, often are much smaller than those of the classical barium stars sometimes only upper limits may be determined. The cause for this difference is not easily understood, but may be related to more extensive mass loss by the mild barium stars. 45 references

  9. Therapeutic Drug Monitoring of Lithium

    DEFF Research Database (Denmark)

    Mose, Tina; Damkier, Per; Petersen, Magnus

    2015-01-01

    BACKGROUND: Serum lithium is monitored to ensure levels within the narrow therapeutic window. This study examines the interlaboratory variation and inaccuracy of lithium monitoring in Denmark. METHODS: In 16 samples consisting of (1) control materials (n = 4), (2) pooled patient serum (n = 5......), and (3) serum from individual patients (n = 7), lithium was measured in 19 laboratories using 20 different instruments. The lithium concentrations were targeted by a reference laboratory. Ion-selective electrode (n = 5), reflective spectrophotometric (RSM, n = 5), and spectrophotometric (n = 10) methods...... of >12%. Seven of these instruments had a systematic positive or negative bias and more so at lower lithium concentrations. Three poorly calibrated instruments were found in the ion-selective electrode group, 3 in the spectrophotometric group, and 2 in the RSM group. The instruments using reflectance...

  10. Development of a large lithium coolant system for operation under vacuum

    International Nuclear Information System (INIS)

    Kolowith, R.; Schwartz, K.E.; Meadows, G.E.; Berg, J.D.

    1983-11-01

    Argon and vacuum systems for the Experimental Lithium System (ELS) were tested to demonstrate vacuum-break capability, vacuum pumping performance, and vacuum sensor compatibility with a hostile liquid metal vapor/aerosol environment. Mechanical, diffusion and cryogenic vacuum pumps were evaluated. High-vacuum levels in the 10 -3 Pa range were achieved over a 270 0 C flowing lithium system. Ionization, thermal conductivity, capacitance manometer, and compound-type pressure sensors were evaluated to determine the effects of this potentially deleterious environment. Screening elbows were evaluated as pressure sensor protective devices. A dual-purpose vacuum-level/nitrogen partial-pressure sensor was evaluated as a means of detecting air in-leakage. Several types of static mechanical vacuum seals were also evaluated. Measurements of the vapor/aerosol generation were made at several system locations and operating conditions

  11. Metal impurity injection into DIVA plasmas with a Q-switched laser beam

    International Nuclear Information System (INIS)

    Yamauchi, Toshihiko; Nagami, Masayuki; Sengoku, Seio; Kumagai, Katsuaki

    1978-08-01

    Metal impurity injection into DIVA plasmas with a Q-switched ruby laser beam is described. Metal materials used are aluminium and gold. The Q-switched laser beam is incident onto a thin metal film thickness about 0.2 μm coated on pyrex glass plate surface. The metal film is vaporized by the laser beam and injected into DIVA plasma. The laser-beam injection method has advantages of sharp profile of vaporized metal, easy control of vaporized metal quantity and injection rate control of metal vapor. (author)

  12. Positive electrode for a lithium battery

    Science.gov (United States)

    Park, Sang-Ho; Amine, Khalil

    2015-04-07

    A method for producing a lithium alkali transition metal oxide for use as a positive electrode material for lithium secondary batteries by a precipitation method. The positive electrode material is a lithium alkali transition metal composite oxide and is prepared by mixing a solid state mixed with alkali and transition metal carbonate and a lithium source. The mixture is thermally treated to obtain a small amount of alkali metal residual in the lithium transition metal composite oxide cathode material.

  13. Laser-induced shockwave propagation from ablation in a cavity

    International Nuclear Information System (INIS)

    Zeng Xianzhong; Mao Xianglei; Mao, Samuel S.; Wen, S.-B.; Greif, Ralph; Russo, Richard E.

    2006-01-01

    The propagation of laser-induced shockwaves from ablation inside of cavities was determined from time-resolved shadowgraph images. The temperature and electron number density of the laser-induced plasma was determined from spectroscopic measurements. These properties were compared to those for laser ablation on the flat surface under the same energy and background gas condition. A theoretical model was proposed to determine the amount of energy and vaporized mass stored in the vapor plume based on these measurements

  14. Halo Star Lithium Depletion

    International Nuclear Information System (INIS)

    Pinsonneault, M. H.; Walker, T. P.; Steigman, G.; Narayanan, Vijay K.

    1999-01-01

    The depletion of lithium during the pre-main-sequence and main-sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. Previous work has indicated a wide range of possible depletion factors, ranging from minimal in standard (nonrotating) stellar models to as much as an order of magnitude in models that include rotational mixing. Recent progress in the study of the angular momentum evolution of low-mass stars permits the construction of theoretical models capable of reproducing the angular momentum evolution of low-mass open cluster stars. The distribution of initial angular momenta can be inferred from stellar rotation data in young open clusters. In this paper we report on the application of these models to the study of lithium depletion in main-sequence halo stars. A range of initial angular momenta produces a range of lithium depletion factors on the main sequence. Using the distribution of initial conditions inferred from young open clusters leads to a well-defined halo lithium plateau with modest scatter and a small population of outliers. The mass-dependent angular momentum loss law inferred from open cluster studies produces a nearly flat plateau, unlike previous models that exhibited a downward curvature for hotter temperatures in the 7Li-Teff plane. The overall depletion factor for the plateau stars is sensitive primarily to the solar initial angular momentum used in the calibration for the mixing diffusion coefficients. Uncertainties remain in the treatment of the internal angular momentum transport in the models, and the potential impact of these uncertainties on our results is discussed. The 6Li/7Li depletion ratio is also examined. We find that the dispersion in the plateau and the 6Li/7Li depletion ratio scale with the absolute 7Li depletion in the plateau, and we use observational data to set bounds on the 7Li depletion in main-sequence halo

  15. Chemical vapor composites (CVC)

    International Nuclear Information System (INIS)

    Reagan, P.

    1993-01-01

    The Chemical Vapor Composite, CVC trademark , process fabricates composite material by simply mixing particles (powders and or fibers) with CVD reactants which are transported and co-deposited on a hot substrate. A key feature of the CVC process is the control provided by varing the density, geometry (aspect ratio) and composition of the entrained particles in the matrix material, during deposition. The process can fabricate composite components to net shape (± 0.013 mm) on a machined substrate in a single step. The microstructure of the deposit is described and several examples of different types of particles in the matrix are illustrated. Mechanical properties of SiC composite material fabricated with SiC powder and fiber will be presented. Several examples of low cost ceramic composite products will be shown. (orig.)

  16. Vapor-droplet flow equations

    International Nuclear Information System (INIS)

    Crowe, C.T.

    1975-01-01

    General features of a vapor-droplet flow are discussed and the equations expressing the conservation of mass, momentum, and energy for the vapor, liquid, and mixture using the control volume approach are derived. The phenomenological laws describing the exchange of mass, momentum, and energy between phases are also reviewed. The results have application to development of water-dominated geothermal resources

  17. Examination results on reaction of lithium

    International Nuclear Information System (INIS)

    Asada, Takashi

    2000-12-01

    Before the material corrosion tests in lithium, the reactions of lithium with air and ammonia that will be used for lithium cleaning were examined, and the results were as follows. 1. When lithium put into air, surface of lithium changes to black first but soon to white, and the white layer becomes gradually thick. The first black of lithium surface is nitride (Li 3 N) and it changes to white lithium hydroxide (LiOH) by reaction with water in air, and it grows. The growth rate of the lithium hydroxide is about 1/10 in the desiccator (humidity of about 10%) compare with in air. 2. When lithium put into nitrogen, surface of lithium changes to black, and soon changes to brown and cracks at surface. At the same time with this cracking, weight of lithium piece increases and nitridation progresses respectively rapidly. This nitridation completed during 1-2 days on lithium rod of 10 mm in diameter, and increase in weight stopped. 3. Lithium melts in liquid ammonia and its melting rate is about 2-3 hour to lithium of 1 g. The liquid ammonia after lithium melting showed dark brown. (author)

  18. Water-Vapor Raman Lidar System Reaches Higher Altitude

    Science.gov (United States)

    Leblanc, Thierry; McDermid, I. Stewart

    2010-01-01

    A Raman lidar system for measuring the vertical distribution of water vapor in the atmosphere is located at the Table Mountain Facility (TMF) in California. Raman lidar systems for obtaining vertical water-vapor profiles in the troposphere have been in use for some time. The TMF system incorporates a number of improvements over prior such systems that enable extension of the altitude range of measurements through the tropopause into the lower stratosphere. One major obstacle to extension of the altitude range is the fact that the mixing ratio of water vapor in the tropopause and the lower stratosphere is so low that Raman lidar measurements in this region are limited by noise. Therefore, the design of the TMF system incorporates several features intended to maximize the signal-to-noise ratio. These features include (1) the use of 355-nm-wavelength laser pulses having an energy (0.9 J per pulse) that is high relative to the laser-pulse energy levels of prior such systems, (2) a telescope having a large aperture (91 cm in diameter) and a narrow field of view (angular width .0.6 mrad), and (3) narrow-bandpass (wavelength bandwidth 0.6 nm) filters for the water-vapor Raman spectral channels. In addition to the large-aperture telescope, three telescopes having apertures 7.5 cm in diameter are used to collect returns from low altitudes.

  19. Diode Laser Sensor for Gas Temperature and H2O Concentration in a Scramjet Combustor Using Wavelength Modulation Spectroscopy (Postprint)

    National Research Council Canada - National Science Library

    Rieker, Gregory B; Li, Jonathan T; Jeffries, Jay B; Mathur, Tarun; Gruber, Mark R; Carter, Campbell D

    2005-01-01

    A diode laser absorption sensor which probes three spectral features of water vapor in the near infrared region to infer gas temperature and water vapor concentration near the exit of a scramjet combustor is presented...

  20. Innovative lasers for uranium isotope separation

    International Nuclear Information System (INIS)

    Brake, M.L.; Gilgenbach, R.M.

    1993-07-01

    Copper vapor laser have important applications to uranium atomic vapor laser isotope separation (AVLIS). We have investigated two innovative methods of exciting/pumping copper vapor lasers which have the potential to improve the efficiency and scaling of large laser systems used in uranium isotope separation. Experimental research has focused on the laser discharge kinetics of (1) microwave, and (2) electron beam excitation/pumping of large-volume copper vapor lasers. Microwave resonant cavity produced copper vapor plasmas at 2.45 GHz, have been investigated in three separate experimental configurations. The first examined the application of CW (0-500W) power and was found to be an excellent method for producing an atomic copper vapor from copper chloride. The second used a pulsed (5kW, 0.5--5 kHz) signal superimposed on the CW signal to attempt to produce vaporization, dissociation and excitation to the laser states. Enhanced emission of the optical radiation was observed but power densities were found to be too low to achieve lasing. In a third experiment we attempted to increase the applied power by using a high power magnetron to produce 100 kW of pulsed power. Unfortunately, difficulties with the magnetron power supply were encountered leaving inconclusive results. Detailed modeling of the electromagnetics of the system were found to match the diagnostics results well. An electron beam pumped copper vapor system (350 kV, 1.0 kA, 300 ns) was investigated in three separate copper chloride heating systems, external chamber, externally heated chamber and an internally heated chamber. Since atomic copper spectral lines were not observed, it is assumed that a single pulse accelerator is not capable of both dissociating the copper chloride and exciting atomic copper and a repetitively pulsed electron beam generator is needed

  1. Deuteron beam interaction with lithium jet in a neutron source test facility

    International Nuclear Information System (INIS)

    Hassanein, A.

    1996-01-01

    Testing and evaluating candidate fusion reactor materials in a high-flux, high-energy neutron environment are critical to the success and economic feasibility of a fusion device. The current understanding of materials behavior in fission-like environments and existing fusion facilities is insufficient to ensure the necessary performance of future fusion reactor components. An accelerator-based deuterium-lithium system to generate the required high neutron flux for material testing is considered to be the most promising approach in the near future. In this system, a high-energy (30-40 MeV) deuteron beam impinges on a high-speed (10-20 m/s) lithium jet to produce the high-energy (≥14 MeV) neutrons required to simulate a fusion environment via the Li (d,n) nuclear stripping reaction. Interaction of the high-energy deuteron beam and the subsequent response of the high-speed lithium jet are evaluated in detail. Deposition of the deuteron beam, jet-thermal hydraulic response, lithium-surface vaporization rate, and dynamic stability of the jet are modeled. It is found that lower beam kinetic energies produce higher surface temperature and consequently higher Li vaporization rates. Larger beam sizes significantly reduce both bulk and surface temperatures. Thermal expansion and dynamic velocities (normal to jet direction) due to beam energy deposition and momentum transfer are much lower than jet flow velocity and decrease substantially at lower beam current densities. (orig.)

  2. Advances in laser isotope separation

    International Nuclear Information System (INIS)

    Herman, I.P.; Bernhardt, A.F.

    1988-01-01

    The physical and chemical concepts required to understand laser isotope separation are presented and discussed. The numerous successful demonstrations of separating isotopes using lasers are reviewed to 1983. Emphasis is placed on the separation of 235-U from 238-U by multi-step selective ioniation of uranium atomic vapor, and on the separation of D and H and of T from D, by pulsed infrared laser multiple-photon dissociation of fluoroform and chloroform, respectively, because they are among the most successful and important examples of laser isotope separation to date. 161 refs.; 7 figs

  3. Vapor pressure and enthalpy of vaporization of aliphatic propanediamines

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Chernyak, Yury

    2012-01-01

    Highlights: ► We measured vapor pressure of four aliphatic 1,3-diamines. ► Vaporization enthalpies at 298 K were derived. ► We examined consistency of new and available data in the literature. ► A group-contribution method for prediction was developed. - Abstract: Vapor pressures of four aliphatic propanediamines including N-methyl-1,3-propanediamine (MPDA), N,N-dimethyl-1,3-propanediamine (DMPDA), N,N-diethyl-1,3-propanediamine (DEPDA) and N,N,N′,N′-tetramethyl-1,3-propanediamine (4MPDA) were measured using the transpiration method. The vapor pressures developed in this work and reported in the literature were used to derive molar enthalpy of vaporization values at the reference temperature 298.15 K. An internal consistency check of the enthalpy of vaporization was performed for the aliphatic propanediamines studied in this work. A group-contribution method was developed for the validation and prediction vaporization enthalpies of amines and diamines.

  4. A Citizen's Guide to Vapor Intrusion Mitigation

    Science.gov (United States)

    This guide describes how vapor intrusion is the movement of chemical vapors from contaminated soil and groundwater into nearby buildings.Vapors primarily enter through openings in the building foundation or basement walls.

  5. Vapor pressure measured with inflatable plastic bag

    Science.gov (United States)

    1965-01-01

    Deflated plastic bag in a vacuum chamber measures initial low vapor pressures of materials. The bag captures the test sample vapors and visual observation of the vapor-inflated bag under increasing external pressures yields pertinent data.

  6. Lithium - no shortage in supply

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Over the last five years the face of the lithium industry has changed with new sources coming onto the market. The result of developments in supply is a buyers' market and, in the absence of major consumer developments, all things point to an increasing severely overcrowded market through the turn of the decade. As such lithium is likely to maintain charismatic appeal as developments unfold. This article provides an overview of the world's lithium industry and looks at the various market uses and potential. (author)

  7. Instrinsic defect energies of lithium hydride and lithium deuteride crystals

    International Nuclear Information System (INIS)

    Pandey, R.; Stoneham, A.M.

    1985-01-01

    A theoretical study has been made of the defect structure of lithium hydride and lithium deuteride. A potential model is obtained describing the statics and dynamics of these crystals. Intrinsic defect energies are calculated using the Harwell HADES program which is based on a generalised Mott-Littleton method. The results are in good agreement with the experimental data, and suggest that the vacancy and interstitial migration mechanisms of anions and cations are all comparable in their contribution to ionic conduction. (author)

  8. Equilibrium dissociation pressures of lithium hydride and lithium deuteride

    International Nuclear Information System (INIS)

    Smith, H.M.; Webb, R.E.

    1977-12-01

    The equilibrium dissociation pressures of plateau composition lithium hydride and lithium deuteride have been measured from 450 to 750 0 C. These data were used to derive the relationship of dissociation pressure with temperature over this range and to calculate several thermodynamic properties of these materials. Thermodynamic properties determined included the enthalpy, entropy, and free energy of formation; the enthalpy and entropy of fusion; and the melting points

  9. Uranium vapor generator: pulsed hollow cathode lamp

    International Nuclear Information System (INIS)

    Carleer, M.; Gagne, J.; Leblanc, B.; Demers, Y.; Mongeau, B.

    1979-01-01

    The production of uranium vapors has been studied in the 5 L 0 6 ground state using a pulsed hollow cathode lamp. The evolution of the 238 U ( 5 L 0 6 ) concentration with time has been studied with Xe and Ar as buffer gases. A density of 2.7 x 10 13 atoms cm -3 was obtained with Xe as a buffer gas. In addition, those measurements, obtained from the absorption of a laser beam tuned to the 5758.143 A ( 5 L 0 6 -17,361 7 L 6 ) transition, allowed the determination of the transition probability A=2.1 x 10 5 sec -1 and of the branching ratio BR=0.08 for this transition

  10. Compact Integrated DBR Laser Source for Absorption Lidar Instruments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to demonstrate a compact integrated laser module that addresses the requirements of the laser source in a water vapor differential absorption lidar (DIAL)...

  11. Passive vapor extraction feasibility study

    International Nuclear Information System (INIS)

    Rohay, V.J.

    1994-01-01

    Demonstration of a passive vapor extraction remediation system is planned for sites in the 200 West Area used in the past for the disposal of waste liquids containing carbon tetrachloride. The passive vapor extraction units will consist of a 4-in.-diameter pipe, a check valve, a canister filled with granular activated carbon, and a wind turbine. The check valve will prevent inflow of air that otherwise would dilute the soil gas and make its subsequent extraction less efficient. The granular activated carbon is used to adsorb the carbon tetrachloride from the air. The wind turbine enhances extraction rates on windy days. Passive vapor extraction units will be designed and operated to meet all applicable or relevant and appropriate requirements. Based on a cost analysis, passive vapor extraction was found to be a cost-effective method for remediation of soils containing lower concentrations of volatile contaminants. Passive vapor extraction used on wells that average 10-stdft 3 /min air flow rates was found to be more cost effective than active vapor extraction for concentrations below 500 parts per million by volume (ppm) of carbon tetrachloride. For wells that average 5-stdft 3 /min air flow rates, passive vapor extraction is more cost effective below 100 ppm

  12. Lithium ion behavior in lithium oxide by neutron scattering studies

    International Nuclear Information System (INIS)

    Ishii, Yoshinobu; Morii, Yukio; Katano, Susumu; Watanabe, Hitoshi; Funahashi, Satoru; Ohno, Hideo; Nicklow, R.M.

    1992-01-01

    Lithium ion behavior in lithium oxide, Li 2 O, was studied in the temperature range from 293 K to 1120 K by the High-Resolution Powder Diffractometer (HRPD) installed in the JRR-3M. The diffraction patterns were analyzed with the RIETAN program. At room temperature, the thermal parameters related to the mean square of the amplitude of vibration of the lithium and the oxygen ions were 6 x 10 -21 m 2 and 4 x 10 -21 m 2 , respectively. AT 1120 K the thermal parameter of the lithium ion was 34 x 10 -21 m 2 . On the other hand, the parameter of the oxygen ion was 16 x 10 -21 m 2 . Inelastic neutron scattering studies for the lithium oxide single crystal were also carried out on the triple-axis neutron spectrometers installed at the JRR-2 and the HFIR. Although the value of a phonon energy of a transverse acoustic mode (Σ 3 ) at zone boundary was 30.6 meV at room temperature, this value was decreased to 25.1 meV at 700 K. This large softening was caused by anharmonicity of the crystal potential of lithium oxide. (author)

  13. Photorefractive effect at 775 nm in doped lithium niobate crystals

    Energy Technology Data Exchange (ETDEWEB)

    Nava, G.; Minzioni, P.; Cristiani, I.; Degiorgio, V. [Department of Electrical, Computer, and Biomedical Engineering, and CNISM, University of Pavia, 27100 Pavia (Italy); Argiolas, N.; Bazzan, M.; Ciampolillo, M. V.; Pozza, G.; Sada, C. [Physics and Astronomy Departement, University of Padova, 35131 Padova (Italy)

    2013-07-15

    The photorefractive effect induced by 775-nm laser light on doped lithium niobate crystals is investigated by the direct observation in the far field of the transmitted-beam distortion as a function of time. Measurements performed at various Zr-doping concentrations and different light intensities show that the 775-nm light beam induces a steady-state photorefractive effect comparable to that of 532-nm light, but the observed build-up time of the photovoltaic field is longer by three-orders of magnitude. The 775-nm photorefractivity of lithium niobate crystals doped with 3 mol. % ZrO{sub 2} or with 5.5 mol. % MgO is found to be negligible.

  14. Optical waveguides in lithium niobate: Recent developments and applications

    Energy Technology Data Exchange (ETDEWEB)

    Bazzan, Marco, E-mail: marco.bazzan@unipd.it; Sada, Cinzia, E-mail: cinzia.sada@unipd.it [Dipartimento di Fisica e Astronomia “G. Galilei,” Università di Padova, Via Marzolo 8, 35131 Padova (Italy)

    2015-12-15

    The state of the art of optical waveguide fabrication in lithium niobate is reviewed, with particular emphasis on new technologies and recent applications. The attention is mainly devoted to recently developed fabrication methods, such as femtosecond laser writing, ion implantation, and smart cut waveguides as well as to the realization of waveguides with tailored functionalities, such as photorefractive or domain engineered structures. More exotic systems, such as reconfigurable and photorefractive soliton waveguides, are also considered. Classical techniques, such as Ti in-diffusion and proton exchange, are cited and briefly reviewed as a reference standpoint to highlight the recent developments. In all cases, the application-oriented point of view is preferred, in order to provide the reader with an up-to date panorama of the vast possibilities offered by lithium niobate to integrated photonics.

  15. Modeling CO2 Laser Ablative Impulse with Polymers

    International Nuclear Information System (INIS)

    Sinko, John E.; Phipps, Claude R.; Sasoh, Akihiro

    2010-01-01

    Laser ablation vaporization models have usually ignored the spatial dependence of the laser beam. Here, we consider effects from modeling using a Gaussian beam for both photochemical and photothermal conditions. The modeling results are compared to experimental and literature data for CO 2 laser ablation of the polymer polyoxymethylene under vacuum, and discussed in terms of the ablated mass areal density and momentum coupling coefficient. Extending the scope of discussion, laser ablative impulse generation research has lacked a cohesive strategy for linking the vaporization and plasma regimes. Existing models, mostly formulated for ultraviolet laser systems or metal targets, appear to be inappropriate or impractical for applications requiring CO 2 laser ablation of polymers. A recently proposed method for linking the vaporization and plasma regimes for analytical modeling is addressed here along with the implications of its use. Key control parameters are considered, along with the major propulsion parameters needed for laser ablation propulsion modeling.

  16. Reversible Lithium Neurotoxicity: Review of the Literature

    Science.gov (United States)

    Netto, Ivan

    2012-01-01

    Objective: Lithium neurotoxicity may be reversible or irreversible. Reversible lithium neurotoxicity has been defined as cases of lithium neurotoxicity in which patients recovered without any permanent neurologic sequelae, even after 2 months of an episode of lithium toxicity. Cases of reversible lithium neurotoxicity differ in clinical presentation from those of irreversible lithium neurotoxicity and have important implications in clinical practice. This review aims to study the clinical presentation of cases of reversible lithium neurotoxicity. Data Sources: A comprehensive electronic search was conducted in the following databases: MEDLINE (PubMed), 1950 to November 2010; PsycINFO, 1967 to November 2010; and SCOPUS (EMBASE), 1950 to November 2010. MEDLINE and PsycINFO were searched by using the OvidSP interface. Study Selection: A combination of the following search terms was used: lithium AND adverse effects AND central nervous system OR neurologic manifestation. Publications cited include articles concerned with reversible lithium neurotoxicity. Data Extraction: The age, sex, clinical features, diagnostic categories, lithium doses, serum lithium levels, precipitating factors, and preventive measures of 52 cases of reversible lithium neurotoxicity were extracted. Data Synthesis: Among the 52 cases of reversible lithium neurotoxicity, patients ranged in age from 10 to 80 years and a greater number were female (P = .008). Most patients had affective disorders, schizoaffective disorders, and/or depression (P lithium levels were less than or equal to 1.5 mEq/L (P lithium, underlying brain pathology, abnormal tissue levels, specific diagnostic categories, and elderly populations were some of the precipitating factors reported for reversible lithium neurotoxicity. The preventive measures were also described. Conclusions: Reversible lithium neurotoxicity presents with a certain clinical profile and precipitating factors for which there are appropriate

  17. Reversible lithium neurotoxicity: review of the literatur.

    Science.gov (United States)

    Netto, Ivan; Phutane, Vivek H

    2012-01-01

    Lithium neurotoxicity may be reversible or irreversible. Reversible lithium neurotoxicity has been defined as cases of lithium neurotoxicity in which patients recovered without any permanent neurologic sequelae, even after 2 months of an episode of lithium toxicity. Cases of reversible lithium neurotoxicity differ in clinical presentation from those of irreversible lithium neurotoxicity and have important implications in clinical practice. This review aims to study the clinical presentation of cases of reversible lithium neurotoxicity. A comprehensive electronic search was conducted in the following databases: MEDLINE (PubMed), 1950 to November 2010; PsycINFO, 1967 to November 2010; and SCOPUS (EMBASE), 1950 to November 2010. MEDLINE and PsycINFO were searched by using the OvidSP interface. A combination of the following search terms was used: lithium AND adverse effects AND central nervous system OR neurologic manifestation. Publications cited include articles concerned with reversible lithium neurotoxicity. The age, sex, clinical features, diagnostic categories, lithium doses, serum lithium levels, precipitating factors, and preventive measures of 52 cases of reversible lithium neurotoxicity were extracted. Among the 52 cases of reversible lithium neurotoxicity, patients ranged in age from 10 to 80 years and a greater number were female (P = .008). Most patients had affective disorders, schizoaffective disorders, and/or depression (P lithium levels were less than or equal to 1.5 mEq/L (P lithium, underlying brain pathology, abnormal tissue levels, specific diagnostic categories, and elderly populations were some of the precipitating factors reported for reversible lithium neurotoxicity. The preventive measures were also described. Reversible lithium neurotoxicity presents with a certain clinical profile and precipitating factors for which there are appropriate preventive measures. This recognition will help in early diagnosis and prompt treatment of

  18. Lasers '89

    International Nuclear Information System (INIS)

    Harris, D.G.; Shay, T.M.

    1990-01-01

    This book covers the following topics: XUV, X-Ray and Gamma-Ray Lasers, excimer lasers, chemical lasers, nuclear pumped lasers, high power gas lasers, solid state lasers, laser spectroscopy. The paper presented include: Development of KrF lasers for fusion and Nuclear driven solid-state lasers

  19. Precipitation of lithium in germanium

    International Nuclear Information System (INIS)

    Masaik, M.; Furgolle, B.

    1969-01-01

    The precipitation of Lithium in Germanium was studied. Taking account of the interactions Ga LI, LiO, we calculated the oxygen content in germanium samples from the resistivity measurements. (authors)

  20. FTU cooled liquid lithium upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Iafrati, M., E-mail: matteo.iafrati@enea.it [Associazione Euratom-ENEA sulla Fusione, C. R. Frascati, C. P. 65-00044 Frascati, Rome (Italy); Apicella, M.L.; Boncagni, L. [Associazione Euratom-ENEA sulla Fusione, C. R. Frascati, C. P. 65-00044 Frascati, Rome (Italy); Lyublinski, I. [JSC “RED STAR”, Moscow (Russian Federation); Mazzitelli, G. [Associazione Euratom-ENEA sulla Fusione, C. R. Frascati, C. P. 65-00044 Frascati, Rome (Italy); Vertkov, A. [JSC “RED STAR”, Moscow (Russian Federation)

    2017-04-15

    In the framework of the liquid lithium limiter experiment in Frascati a new auxiliary system was developed in order to provide a better control of the energy fluid vector. The cooled liquid lithium system (CLL) was installed for the first time at the end of 2013, it uses overheated water to heat the lithium and to extract, at the same time, the heat from the metal surface when it gets wet by the plasma. A first version of the system, developed and presented in previous papers, has been modified to optimize the heat flux measurement on the liquid lithium surface. The changes include a new power supply logic for the heating system, new sensors and new read-out electronics compatible with the implementation of a real time control system. The prototype was updated with the aim of achieving a low cost and versatile control system.