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Sample records for solid deuterium irradiated

  1. Spectral irradiance standard for the ultraviolet - The deuterium lamp

    NASA Technical Reports Server (NTRS)

    Saunders, R. D.; Ott, W. R.; Bridges, J. M.

    1978-01-01

    A set of deuterium lamps is calibrated as spectral irradiance standards in the 200-350-nm spectral region utilizing both a high accuracy tungsten spectral irradiance standard and a newly developed argon mini-arc spectral radiance standard. The method which enables a transfer from a spectral radiance to a spectral irradiance standard is described. The following characteristics of the deuterium lamp irradiance standard are determined: sensitivity to alignment; dependence on input power and solid angle; reproducibility; and stability. The absolute spectral radiance is also measured in the 167-330-nm region. Based upon these measurements, values of the spectral irradiance below 200 nm are obtained through extrapolation.

  2. Solid deuterium centrifuge pellet injector

    SciTech Connect

    Foster, C.A.

    1982-01-01

    Pellet injectors are needed to fuel long pulse tokamak plasmas and other magnetic confinement devices. For this purpose, an apparatus has been developed that forms 1.3-mm-diam pellets of frozen deuterium at a rate of 40 pellets per second and accelerates them to a speed of 1 km/s. Pellets are formed by extruding a billet of solidified deuterium through a 1.3-mm-diam nozzle at a speed of 5 cm/s. The extruding deuterium is chopped with a razor knife, forming 1.3-mm right circular cylinders of solid deuterium. The pellets are accelerated by synchronously injecting them into a high speed rotating arbor containing a guide track, which carries them from a point near the center of rotation to the periphery. The pellets leave the wheel after 150/sup 0/ of rotation at double the tip speed. The centrifuge is formed in the shape of a centrifugal catenary and is constructed of high strength KEVLAR/epoxy composite. This arbon has been spin-tested to a tip speed of 1 km/s.

  3. Neutron scattering kernel for solid deuterium

    NASA Astrophysics Data System (ADS)

    Granada, J. R.

    2009-06-01

    A new scattering kernel to describe the interaction of slow neutrons with solid deuterium was developed. The main characteristics of that system are contained in the formalism, including the lattice's density of states, the Young-Koppel quantum treatment of the rotations, and the internal molecular vibrations. The elastic processes involving coherent and incoherent contributions are fully described, as well as the spin-correlation effects. The results from the new model are compared with the best available experimental data, showing very good agreement.

  4. Structural Transformations in Austenitic Stainless Steel Induced by Deuterium Implantation: Irradiation at 295 K

    NASA Astrophysics Data System (ADS)

    Morozov, Oleksandr; Zhurba, Volodymir; Neklyudov, Ivan; Mats, Oleksandr; Progolaieva, Viktoria; Boshko, Valerian

    2016-02-01

    Deuterium thermal desorption spectra were investigated on the samples of austenitic steel 18Cr10NiTi pre-implanted at 295 K with deuterium ions in the dose range from 8 × 1014 to 2.7 × 1018 D/cm2. The kinetics of structural transformation development in the steel layer was traced from deuterium thermodesorption spectra as a function of deuterium concentration. Three characteristic regions with different low rates of deuterium amount desorption as the implantation dose increases were revealed: I—the linear region of low implantation doses (up to 1 × 1017 D/cm2); II—the nonlinear region of medium implantation doses (1 × 1017 to 8 × 1017 D/cm2); III—the linear region of high implantation doses (8 × 1017 to 2.7 × 1018 D/cm2). During the process of deuterium ion irradiation, the coefficient of deuterium retention in steel varies in discrete steps. Each of the discrete regions of deuterium retention coefficient variation corresponds to different implanted-matter states formed during deuterium ion implantation. The low-dose region is characterized by formation of deuterium-vacancy complexes and solid-solution phase state of deuterium in the steel. The total concentration of the accumulated deuterium in this region varies between 2.5 and 3 at.%. The medium-dose region is characterized by the radiation-induced action on the steel in the presence of deuterium with the resulting formation of the energy-stable nanosized crystalline structure of steel, having a developed network of intercrystalline boundaries. The basis for this developed network of intercrystalline boundaries is provided by the amorphous state, which manifests itself in the thermodesorption spectra as a widely temperature-scale extended region of deuterium desorption (structure formation with a varying activation energy). The total concentration of the accumulated deuterium in the region of medium implantation doses makes 7 to 8 at.%. The resulting structure shows stability against the action of

  5. Structural Transformations in Austenitic Stainless Steel Induced by Deuterium Implantation: Irradiation at 295 K.

    PubMed

    Morozov, Oleksandr; Zhurba, Volodymir; Neklyudov, Ivan; Mats, Oleksandr; Progolaieva, Viktoria; Boshko, Valerian

    2016-12-01

    Deuterium thermal desorption spectra were investigated on the samples of austenitic steel 18Cr10NiTi pre-implanted at 295 K with deuterium ions in the dose range from 8 × 10(14) to 2.7 × 10(18) D/cm(2). The kinetics of structural transformation development in the steel layer was traced from deuterium thermodesorption spectra as a function of deuterium concentration. Three characteristic regions with different low rates of deuterium amount desorption as the implantation dose increases were revealed: I-the linear region of low implantation doses (up to 1 × 10(17) D/cm(2)); II-the nonlinear region of medium implantation doses (1 × 10(17) to 8 × 10(17) D/cm(2)); III-the linear region of high implantation doses (8 × 10(17) to 2.7 × 10(18) D/cm(2)). During the process of deuterium ion irradiation, the coefficient of deuterium retention in steel varies in discrete steps. Each of the discrete regions of deuterium retention coefficient variation corresponds to different implanted-matter states formed during deuterium ion implantation. The low-dose region is characterized by formation of deuterium-vacancy complexes and solid-solution phase state of deuterium in the steel. The total concentration of the accumulated deuterium in this region varies between 2.5 and 3 at.%. The medium-dose region is characterized by the radiation-induced action on the steel in the presence of deuterium with the resulting formation of the energy-stable nanosized crystalline structure of steel, having a developed network of intercrystalline boundaries. The basis for this developed network of intercrystalline boundaries is provided by the amorphous state, which manifests itself in the thermodesorption spectra as a widely temperature-scale extended region of deuterium desorption (structure formation with a varying activation energy). The total concentration of the accumulated deuterium in the region of medium implantation doses makes 7 to 8 at.%. The

  6. Study of ion-irradiated tungsten in deuterium plasma

    NASA Astrophysics Data System (ADS)

    Khripunov, B. I.; Gureev, V. M.; Koidan, V. S.; Kornienko, S. N.; Latushkin, S. T.; Petrov, V. B.; Ryazanov, A. I.; Semenov, E. V.; Stolyarova, V. G.; Danelyan, L. S.; Kulikauskas, V. S.; Zatekin, V. V.; Unezhev, V. N.

    2013-07-01

    Experimental study aimed at investigation of neutron induced damage influence on fusion reactor plasma facing materials is reported. Displacement damage was produced in tungsten by high-energy helium and carbon ions at 3-10 MeV. The reached level of displacement damage ranged from several dpa to 600 dpa. The properties of the irradiated tungsten were studied in steady-state deuterium plasma on the LENTA linear divertor simulator. Plasma exposures were made at 250 eV of ion energy to fluence 1021-1022 ion/сm2. Erosion dynamics of the damaged layer and deuterium retention were observed. Surface microstructure modifications and important damage of the 5 μm layer shown. Deuterium retention in helium-damaged tungsten (ERD) showed its complex behavior (increase or decrease) depending on implanted helium quantity and the structure of the surface layer.

  7. Deuterium Enrichment of PAHs by VUV Irradiation of Interstellar Ices

    NASA Technical Reports Server (NTRS)

    Bernstein, Max P.; Sandford, Scott A.; Allamandola, Louis J.; Gillette, J. Seb; Zare, Richard N.; DeVincenzi, Donald (Technical Monitor)

    1998-01-01

    Laboratory results demonstrate that polycyclic aromatic hydrocarbons (PAHs) rapidly exchange their hydrogen atoms with those of nearby molecules when they are frozen into low-temperature ices and exposed to vacuum ultraviolet radiation. As a result, PAHs quickly become deuterium-enriched when VUV irradiated in D-containing ices. This mechanism has important consequences for several astrophysical issues owing to the ubiquitous nature of PAHs in the interstellar medium. For example, this process may explain the deuterium enrichments found in PAHs in meteorites and interplanetary dust particles. These results also provide general predictions about the molecular siting of the deuterium on aromatic materials in meteorites if this process produced a significant fraction of their D-enrichment.

  8. Chemical response of lithiated graphite with deuterium irradiation

    SciTech Connect

    Taylor, C. N.; Heim, B.; Allain, J. P.

    2011-03-01

    Lithium wall conditioning has been found to enhance plasma performance for graphite walled fusion devices such as TFTR, CDX-U, T-11M, TJ-II and NSTX. Among observed plasma enhancements is a reduction in edge density and reduced deuterium recycling. The mechanism by which lithiated graphite retains deuterium is largely unknown. Under controlled laboratory conditions, X-ray photoelectron spectroscopy (XPS) is used to observe the chemical changes that occur on ATJ graphite after lithium deposition. The chemical state of lithiated graphite is found to change upon deuterium irradiation indicating the formation Li-O-D, manifest at 532.9 {+-} 0.6 eV. Lithium-deuterium interactions are also manifest in the C 1s photoelectron energy range and show Li-C-D interactions at 291.2 {+-} 0.6 eV. Post-mortem NSTX tiles that have been exposed to air upon extraction are cleaned and examined, revealing the chemical archaeology that formed during NSTX operations. XPS spectra show strong correlation ({+-} 0.3 eV) in Li-O-D and Li-O peaks from post-mortem and control experiments, thus validating offline experiments. We report findings that show that deuterium is found to interact with lithium after lithium has already reacted with carbon and oxygen.

  9. Chemical response of lithiated graphite with deuterium irradiation

    NASA Astrophysics Data System (ADS)

    Taylor, C. N.; Heim, B.; Allain, J. P.

    2011-03-01

    Lithium wall conditioning has been found to enhance plasma performance for graphite walled fusion devices such as TFTR, CDX-U, T-11M, TJ-II and NSTX. Among observed plasma enhancements is a reduction in edge density and reduced deuterium recycling. The mechanism by which lithiated graphite retains deuterium is largely unknown. Under controlled laboratory conditions, X-ray photoelectron spectroscopy (XPS) is used to observe the chemical changes that occur on ATJ graphite after lithium deposition. The chemical state of lithiated graphite is found to change upon deuterium irradiation indicating the formation Li-O-D, manifest at 532.9 ± 0.6 eV. Lithium-deuterium interactions are also manifest in the C 1s photoelectron energy range and show Li-C-D interactions at 291.2 ± 0.6 eV. Post-mortem NSTX tiles that have been exposed to air upon extraction are cleaned and examined, revealing the chemical archaeology that formed during NSTX operations. XPS spectra show strong correlation (± 0.3 eV) in Li-O-D and Li-O peaks from post-mortem and control experiments, thus validating offline experiments. We report findings that show that deuterium is found to interact with lithium after lithium has already reacted with carbon and oxygen.

  10. ELECTRON IRRADIATION OF SOLIDS

    DOEpatents

    Damask, A.C.

    1959-11-01

    A method is presented for altering physical properties of certain solids, such as enhancing the usefulness of solids, in which atomic interchange occurs through a vacancy mechanism, electron irradiation, and temperature control. In a centain class of metals, alloys, and semiconductors, diffusion or displacement of atoms occurs through a vacancy mechanism, i.e., an atom can only move when there exists a vacant atomic or lattice site in an adjacent position. In the process of the invention highenergy electron irradiation produces additional vacancies in a solid over those normally occurring at a given temperature and allows diffusion of the component atoms of the solid to proceed at temperatures at which it would not occur under thermal means alone in any reasonable length of time. The invention offers a precise way to increase the number of vacancies and thereby, to a controlled degree, change the physical properties of some materials, such as resistivity or hardness.

  11. Hydrogen and deuterium NMR of solids by magic angle spinning

    SciTech Connect

    Eckman, Richard Raymond

    1982-10-01

    The nuclear magnetic resonance of solids has long been characterized by very large spectral broadening which arises from internuclear dipole-dipole coupling or the nuclear electric quadrupole interaction. These couplings can obscure the smaller chemical shift interaction and make that information unavailable. Two important and difficult cases are that of hydrogen and deuterium. For example, the homonuclear dipolar broadening, HD, for hydrogen is usually several tens of kilohertz. For deuterium, HD is relatively small; however, the quadrupole interaction causes a broadening which can be hundreds of kilohertz in polycrystalline or amorphous solids. The development of cross polarization, heteronuclear radiofrequency decoupling, and coherent averaging of nuclear spin interactions has provided measurement of chemical shift tensors in solids. Recently, double quantum NMR and double quantum decoupling have led to measurement of deuterium and proton chemical shift tensors, respectively. A general problem of these experiments is the overlapping of the tensor powder pattern spectra of magnetically distinct sites which cannot be resolved. In this work, high resolution NMR of hydrogen and deuterium in solids is demonstrated. For both nuclei, the resonances are narrowed to obtain liquid-like isotropic spectra by high frequency rotation of the sample about an axis inclined at the magic angle, βm = Arccos(3-1/2), with respect to the direction of the external magnetic field. Two approaches have been developed for each nucleus. For deuterium, the powder spectra were narrowed by over three orders of magnitude by magic angle rotation with precise control of β. A second approach was the observation of deuterium double quantum transitions under magic angle rotation. For hydrogen, magic angle rotation alone could be applied to obtain the isotropic spectrum when HD was small. This often occurs naturally when the nuclei are semi-dilute or involved in

  12. Irradiation effect on deuterium behaviour in low-dose HFIR neutron-irradiated tungsten

    SciTech Connect

    Shimada, Masashi; Cao, G.; Otsuka, T.; Hara, M.; Kobayashi, M.; Oya, Y.; Hatano, Y.

    2014-12-01

    Tungsten samples were irradiated by neutrons in the High Flux Isotope Reactor, Oak Ridge National Laboratory at reactor coolant temperatures of 50-70°C to low displacement damage of 0.025 and 0.3 dpa under the framework of the US-Japan TITAN program (2007-2013). After cooling down, the HFIR neutron-irradiated tungsten samples were exposed to deuterium plasmas in the Tritium Plasma Experiment, Idaho National Laboratory at 100, 200 and 500 °C twice at the ion fluence of 5×10²⁵ m⁻² to reach a total ion fluence of 1×10²⁶ m⁻² in order to investigate the near surface deuterium retention and saturation via nuclear reaction analysis. Final thermal desorption spectroscopy was performed to elucidate irradiation effect on total deuterium retention. Nuclear reaction analysis results showed that the maximum near surface (<5 µm depth) deuterium concentration increased from 0.5 at % D/W in 0.025 dpa samples to 0.8 at. % D/W in 0.3 dpa samples. The large discrepancy between the total retention via thermal desorption spectroscopy and the near surface retention via nuclear reaction analysis indicated the deuterium was migrated and trapped in bulk (at least 50 µm depth for 0.025 dpa and 35 µm depth for 0.025 dpa) at 500 °C case even in the relatively low ion fluence of 10²⁶ m⁻².

  13. Irradiation effect on deuterium behaviour in low-dose HFIR neutron-irradiated tungsten

    DOE PAGES

    Shimada, Masashi; Cao, G.; Otsuka, T.; ...

    2014-12-01

    Tungsten samples were irradiated by neutrons in the High Flux Isotope Reactor, Oak Ridge National Laboratory at reactor coolant temperatures of 50-70°C to low displacement damage of 0.025 and 0.3 dpa under the framework of the US-Japan TITAN program (2007-2013). After cooling down, the HFIR neutron-irradiated tungsten samples were exposed to deuterium plasmas in the Tritium Plasma Experiment, Idaho National Laboratory at 100, 200 and 500 °C twice at the ion fluence of 5×10²⁵ m⁻² to reach a total ion fluence of 1×10²⁶ m⁻² in order to investigate the near surface deuterium retention and saturation via nuclear reaction analysis. Finalmore » thermal desorption spectroscopy was performed to elucidate irradiation effect on total deuterium retention. Nuclear reaction analysis results showed that the maximum near surface (<5 µm depth) deuterium concentration increased from 0.5 at % D/W in 0.025 dpa samples to 0.8 at. % D/W in 0.3 dpa samples. The large discrepancy between the total retention via thermal desorption spectroscopy and the near surface retention via nuclear reaction analysis indicated the deuterium was migrated and trapped in bulk (at least 50 µm depth for 0.025 dpa and 35 µm depth for 0.025 dpa) at 500 °C case even in the relatively low ion fluence of 10²⁶ m⁻².« less

  14. Effect of helium irradiation on deuterium permeation behavior in tungsten

    NASA Astrophysics Data System (ADS)

    Uemura, Yuki; Sakurada, Shodai; Fujita, Hiroe; Azuma, Keisuke; Zhou, Quilai; Hatano, Yuji; Yoshida, Naoaki; Watanabe, Hideo; Oyaizu, Makoto; Isobe, Kanetsugu; Shimada, Masashi; Buchenauer, Dean; Kolasinski, Robert; Chikada, Takumi; Oya, Yasuhisa

    2017-07-01

    In this study, we measured deuterium (D) gas-driven permeation through tungsten (W) foils that had been pre-damaged by helium ions (He+). The goal of this work was to determine how ion-induced damage affects hydrogen isotope permeation. At 873 K, the D permeability for W irradiated by 3.0 keV He+ was approximately one order of magnitude lower than that for un-damaged W. This difference diminished with increasing temperature. Even after heating to 1173 K, the permeability returned to less than half of the value measured for un-damaged W. We propose that this is due to nucleation of He bubbles near the surface which potentially serve as a barrier to diffusion deeper into the bulk. Exposure at higher temperatures shows that the D permeability and diffusion coefficients return to levels observed for undamaged material. It is possible that these effects are linked to annealing of defects introduced by ion damage, and whether the defects are stabilized by the presence of trapped He.

  15. Comparison of Deuterium Retention for Ion-irradiated and Neutron-irradiated Tungsten

    SciTech Connect

    Yasuhisa Oya; Masashi Shimada; Makoto Kobayashi; Takuji Oda; Masanori Hara; Hideo Watanabe; Yuji Hatano; Pattrick Calderoni; Kenji Okuno

    2011-12-01

    The behavior of D retention for Fe{sup 2+}-irradiated tungsten with a damage of 0.025-3 dpa was compared with that for neutron-irradiated tungsten with 0.025 dpa. The D{sub 2} thermal desorption spectroscopy (TDS) spectra for Fe{sup 2+}-irradiated tungsten consisted of two desorption stages at 450 and 550 K, while that for neutron-irradiated tungsten was composed of three stages and an addition desorption stage was found at 750 K. The desorption rate of the major desorption stage at 550K increased as the displacement damage increased due to Fe{sup 2+} irradiation increasing. In addition, the first desorption stage at 450K was found only for damaged samples. Therefore, the second stage would be based on intrinsic defects or vacancy produced by Fe{sup 2+} irradiation, and the first stage should be the accumulation of D in mono-vacancy and the activation energy would be relatively reduced, where the dislocation loop and vacancy is produced. The third one was found only for neutron irradiation, showing the D trapping by a void or vacancy cluster, and the diffusion effect is also contributed to by the high full-width at half-maximum of the TDS spectrum. Therefore, it can be said that the D{sub 2} TDS spectra for Fe{sup 2+}-irradiated tungsten cannot represent that for the neutron-irradiated one, indicating that the deuterium trapping and desorption mechanism for neutron-irradiated tungsten is different from that for the ion-irradiated one.

  16. Magnetohydrodynamic Simulation of Solid-Deuterium - Z-Pinch Experiments

    NASA Astrophysics Data System (ADS)

    Sheehey, Peter Trogdon

    Solid-deuterium-initiated Z-pinch experiments are numerically simulated using a two-dimensional resistive magnetohydrodynamic model, which includes many important experimental details, such as "cold-start" initial conditions, thermal conduction, radiative energy loss, actual discharge current vs. time, and grids of sufficient size and resolution to allow realistic development of the plasma. The alternating -direction-implicit numerical technique used meets the substantial demands presented by such a computational task. Simulations of fiber-initiated experiments show that when the fiber becomes fully ionized (at a time depending on current ramp and fiber thickness), rapidly developing m = 0 instabilities, which originated in the coronal plasma generated from the ablating fiber, drive intense non-uniform heating and rapid expansion of the plasma column. The possibility that inclusion of additional physical effects would improve stability is explored. Finite-Larmor-radius-ordered Hall and diamagnetic pressure terms in the magnetic field evolution equation, corresponding energy equation terms, and separate ion and electron energy equations are included; these do not change the basic results. Model diagnostics, such as shadowgrams and interferograms, generated from simulation results, are in good agreement with experiment. Two alternative experimental approaches are explored: high-current magnetic implosion of hollow cylindrical deuterium shells, and "plasma -on wire" (POW) implosion of low-density plasma onto a central deuterium fiber. By minimizing instability problems, these techniques may allow attainment of higher temperatures and densities than possible with bare fiber-initiated Z -pinches. Conditions for significant D-D or D-T fusion neutron production may be realizable with these implosion -based approaches.

  17. Disassembly time of deuterium-cluster-fusion plasma irradiated by an intense laser pulse

    SciTech Connect

    Bang, W.

    2015-07-02

    Energetic deuterium ions from large deuterium clusters (>10 nm diameter) irradiated by an intense laser pulse (>10¹⁶ W/cm²) produce DD fusion neutrons for a time interval determined by the geometry of the resulting fusion plasma. We show an analytical solution of this time interval, the plasma disassembly time, for deuterium plasmas that are cylindrical in shape. Assuming a symmetrically expanding deuterium plasma, we calculate the expected fusion neutron yield and compare with an independent calculation of the yield using the concept of a finite confinement time at a fixed plasma density. The calculated neutron yields agree quantitatively with the available experimental data. Our one-dimensional simulations indicate that one could expect a tenfold increase in total neutron yield by magnetically confining a 10 - keV deuterium fusion plasma for 10 ns.

  18. Disassembly time of deuterium-cluster-fusion plasma irradiated by an intense laser pulse

    DOE PAGES

    Bang, W.

    2015-07-02

    Energetic deuterium ions from large deuterium clusters (>10 nm diameter) irradiated by an intense laser pulse (>10¹⁶ W/cm²) produce DD fusion neutrons for a time interval determined by the geometry of the resulting fusion plasma. We show an analytical solution of this time interval, the plasma disassembly time, for deuterium plasmas that are cylindrical in shape. Assuming a symmetrically expanding deuterium plasma, we calculate the expected fusion neutron yield and compare with an independent calculation of the yield using the concept of a finite confinement time at a fixed plasma density. The calculated neutron yields agree quantitatively with the availablemore » experimental data. Our one-dimensional simulations indicate that one could expect a tenfold increase in total neutron yield by magnetically confining a 10 - keV deuterium fusion plasma for 10 ns.« less

  19. Development of positron annihilation spectroscopy for investigating deuterium decorated voids in neutron-irradiated tungsten

    NASA Astrophysics Data System (ADS)

    Taylor, C. N.; Shimada, M.; Merrill, B. J.; Akers, D. W.; Hatano, Y.

    2015-08-01

    The present work is a continuation of a recent research to develop and optimize positron annihilation spectroscopy (PAS) for characterizing neutron-irradiated tungsten. Tungsten samples were exposed to neutrons in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory and damaged to 0.025 and 0.3 dpa. Subsequently, they were exposed to deuterium plasmas in the Tritium Plasma Experiment (TPE) at Idaho National Laboratory. The implanted deuterium was desorbed through sample heating to 900 °C, and Doppler broadening (DB)-PAS was performed both before and after heating. Results show that deuterium impregnated tungsten is identified as having a smaller S-parameter. The S-parameter increases after deuterium desorption. Microstructural changes also occur during sample heating. These effects can be isolated from deuterium desorption by comparing the S-parameters from the deuterium-free back face with the deuterium-implanted front face. The application of using DB-PAS to examine deuterium retention in tungsten is examined.

  20. Ultrasonic irradiation of deuterium-loaded palladium particles suspended in heavy water

    SciTech Connect

    Jorne, J.

    1996-01-01

    Ultrasonic irradiation of a slurry of deuterium-loaded palladium powder (1 {mu}m) suspended in heavy water causes cavitation and high-speed collisions between the palladium particles. High local temperatures, estimated at above the melting point of palladium (1828 K), cause melting and interparticle fusion. The expectation that such collisions can induce high stresses within the palladium particles and lead to favorable conditions for nuclear cold fusion of the deuterium atoms within the palladium lattice is checked by measuring the neutron rates during ultrasonic irradiation. Several bursts of neutron counting are observed and can be accounted for as background anomalism, although the highest observed neutron rate is about four times the background and cannot be explained as background. The X-ray photoelectron spectroscopy analysis of the deuterium-loaded palladium powders reveals that after ultrasonic irradiation in heavy water, the palladium powder becomes partially oxidized and undergoes some compositional changes. 18 refs., 7 figs., 1 tab.

  1. Density of states in solid deuterium: Inelastic neutron scattering study

    SciTech Connect

    Frei, A.; Gutsmiedl, E.; Morkel, C.; Mueller, A. R.; Paul, S.; Urban, M.; Schober, H.; Rols, S.; Unruh, T.; Hoelzel, M.

    2009-08-01

    The dynamics of solid deuterium (sD{sub 2}) is studied by means of inelastic scattering (coherent and incoherent) of thermal and cold neutrons at different temperatures and para-ortho ratios. In this paper, the results for the generalized density of states (GDOS) are presented and discussed. The measurements were performed at the thermal neutron time-of-flight (TOF) instrument IN4 at ILL Grenoble and at the cold neutron TOF instrument TOFTOF at FRM II Garching. The GDOS comprises besides the hcp phonon excitations of the sD{sub 2} the rotational transitions J=0{yields}1 and J=1{yields}2. The intensities of these rotational excitations depend strongly on the ortho-D{sub 2} molecule concentration c{sub o} in sD{sub 2}. Above E=10 meV there are still strong excitations, which very likely may originate from higher-energy damped optical phonons and multiphonon contributions. A method for separating the one-phonon and multiphonon contributions to the density of states will be presented and discussed.

  2. Deuterium Depth Profile in Neutron-Irradiated Tungsten Exposed to Plasma

    SciTech Connect

    Masashi Shimada; G. Cao; Y. Hatano; T. Oda; Y. Oya; M. Hara; P. Calderoni

    2011-05-01

    The effect of radiation damage has been mainly simulated using high-energy ion bombardment. The ions, however, are limited in range to only a few microns into the surface. Hence, some uncertainty remains about the increase of trapping at radiation damage produced by 14 MeV fusion neutrons, which penetrate much farther into the bulk material. With the Japan-US joint research project: Tritium, Irradiations, and Thermofluids for America and Nippon (TITAN), the tungsten samples (99.99 % pure from A.L.M.T., 6mm in diameter, 0.2mm in thickness) were irradiated to high flux neutrons at 50 C and to 0.025 dpa in the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory (ORNL). Subsequently, the neutron-irradiated tungsten samples were exposed to a high-flux deuterium plasma (ion flux: 1021-1022 m-2s-1, ion fluence: 1025-1026 m-2) in the Tritium Plasma Experiment (TPE) at the Idaho National Laboratory (INL). First results of deuterium retention in neutron-irradiated tungsten exposed in TPE have been reported previously. This paper presents the latest results in our on-going work of deuterium depth profiling in neutron-irradiated tungsten via nuclear reaction analysis. The experimental data is compared with the result from non neutron-irradiated tungsten, and is analyzed with the Tritium Migration Analysis Program (TMAP) to elucidate the hydrogen isotope behavior such as retention and depth distribution in neutron-irradiated and non neutron-irradiated tungsten.

  3. Studies of Molecular Dynamics by Solid State Deuterium NMR Spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhao, Baiyi

    The rotational dynamics of molecules in a number of solid systems were followed by variable temperature deuterium (^2H), nuclear magnetic resonance (NMR) spectroscopy via changes in the spectral lineshapes and spin-lattice relaxation times (T _1). First the pure solid trimethylamine-borane adduct, (CH_3)_3NBH_3, was studied. For a methyl deuterated sample, T _1 measurements yielded two T_1 minima, 6.9 ms and 4.3 ms corresponding to the slowing of methyl and trimethyl rotation, respectively, with decreasing temperature. Activation energies for methyl and trimethyl rotation, obtained from fitting the T _1 curve as a function of temperature, were 32.8 and 15.0 kJ/mol, respectively; simulations of the spectral lineshapes gave 26.6 and 18.9 kT/mol, respectively. Fitting of the ^2H T_1 curve for the borane deuterated sample gave a BH _3 rotation activation energy of 14.1 kT/mol and a ^2H quadrupolar coupling constant, chi, of 101 kHz. The activation energy for BH_3 rotation obtained from the spectral lineshape simulations gave 12.6 kT/mol. A series of deuterated organic chalcogen cations: (CH_3)_3S^+, (CH_3)_3Se^+ and (CH_3)_3Te^+, were ion exchanged into the cavities of sodium Mordenite LZ-M5 and the dynamics of these guests within the hydrated zeolite were followed by ^2H NMR. All three undergo isotropic motion above about -80 to -90^circC. Below this temperature two superimposed ^2H powder spectra appear; the broad lineshape is consistent with only methyl rotation in a hindered, coordinated site, and the other narrow lineshape is due to both methyl and trimethyl rotation in a less hindered, uncoordinated site. As the temperature is lowered the population of the lower energy coordinated site increases. Relative peak areas yield adsorption enthalpies of 6.7, 7.8 and 10.0 kJ/mol for (CH_3)_3S^+, (CH_3)_3Se^+ and (CH_3)_3Te^+, respectively. The series of methyl deuterated ammonium and phosphonium cations: (CH_3)NH_3^+ , (CH_3)_2NH^+ , (CH_3)_3NH^+ and (CH_3)_4P^+ , were

  4. Microstructure and deuterium retention after ion irradiation of W-Lu2O3 composites

    NASA Astrophysics Data System (ADS)

    Lin, Jin-Shan; Luo, Lai-Ma; Xu, Qiu; Zan, Xiang; Zhu, Xiao-Yong; Wu, Yu-Cheng

    2017-07-01

    W-3Lu2O3 composites were prepared by mechanical milling and spark plasma sintering. The obtained composites were subjected to He+ irradiation experiments. The irradiated samples were characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and measurement of Vickers hardness. Thermal desorption spectroscopy analysis was performed to analyze the samples at different damage levels after Fe2+ and D+ irradiation. Results showed varied degrees of He+ damage under different energies. Fuzz structures were observed on the surface of the material after irradiation. TEM results indicated that the existence of these fuzz structures was related to the formation of He bubbles. Amorphous, polycrystalline, and γ-W phases formed in areas where He bubbles existed. The measured Vickers hardness proved that radiation hardening occurred after irradiation. After Fe2+ irradiation at different damage levels, the total retained deuterium amount of W-3Lu2O3 and pure W differed, and the impact of Fe2+ radiation for deuterium retention on pure tungsten was greater.

  5. Defect annealing and thermal desorption of deuterium in low dose HFIR neutron-irradiated tungsten

    SciTech Connect

    Masashi Shimada; M. Hara; T. Otsuka; Y. Oya; Y. Hatano

    2014-05-01

    Accurately estimating tritium retention in plasma facing components (PFCs) and minimizing its uncertainty are key safety issues for licensing future fusion power reactors. D-T fusion reactions produce 14.1 MeV neutrons that activate PFCs and create radiation defects throughout the bulk of the material of these components. Recent studies show that tritium migrates and is trapped in bulk (>> 10 µm) tungsten beyond the detection range of nuclear reaction analysis technique [1-2], and thermal desorption spectroscopy (TDS) technique becomes the only established diagnostic that can reveal hydrogen isotope behavior in in bulk (>> 10 µm) tungsten. Radiation damage and its recovery mechanisms in neutron-irradiated tungsten are still poorly understood, and neutron-irradiation data of tungsten is very limited. In this paper, systematic investigations with repeated plasma exposures and thermal desorption are performed to study defect annealing and thermal desorption of deuterium in low dose neutron-irradiated tungsten. Three tungsten samples (99.99 at. % purity from A.L.M.T. Co., Japan) irradiated at High Flux Isotope Reactor at Oak Ridge National Laboratory were exposed to high flux (ion flux of (0.5-1.0)x1022 m-2s-1 and ion fluence of 1x1026 m-2) deuterium plasma at three different temperatures (100, 200, and 500 °C) in Tritium Plasma Experiment at Idaho National Laboratory. Subsequently, thermal desorption spectroscopy (TDS) was performed with a ramp rate of 10 °C/min up to 900 °C, and the samples were annealed at 900 °C for 0.5 hour. These procedures were repeated three (for 100 and 200 °C samples) and four (for 500 °C sample) times to uncover damage recovery mechanisms and its effects on deuterium behavior. The results show that deuterium retention decreases approximately 90, 75, and 66 % for 100, 200, and 500 °C, respectively after each annealing. When subjected to the same TDS recipe, the desorption temperature shifts from 800 °C to 600 °C after 1st annealing

  6. Isotope effects in dense solid hydrogen - Phase transition in deuterium at 190 + or - 20 GPa

    NASA Technical Reports Server (NTRS)

    Hemley, R. J.; Mao, H. K.

    1989-01-01

    Raman measurements of solid normal deuterium compressed in a diamond-anvil cell indicate that the material undergoes a structural phase transformation at 190 + or - 20 GPa and 77 K. Spectroscopically, the transition appears analogous to that observed in hydrogen at 145 + or - 5 GPa. The large isotope effect on the transition pressure suggests there is a significant vibrational contribution to the relative stability of the solid phases of hydrogen at very high densities.

  7. Hydrogen and deuterium NMR of solids by magic-angle spinning

    SciTech Connect

    Eckman, R.R.

    1982-10-01

    The nuclear magnetic resonance of solids has long been characterized by very large specral broadening which arises from internuclear dipole-dipole coupling or the nuclear electric quadrupole interaction. These couplings can obscure the smaller chemical shift interaction and make that information unavailable. Two important and difficult cases are that of hydrogen and deuterium. The development of cross polarization, heteronuclear radiofrequency decoupling, and coherent averaging of nuclear spin interactions has provided measurement of chemical shift tensors in solids. Recently, double quantum NMR and double quantum decoupling have led to measurement of deuterium and proton chemical shift tensors, respectively. A general problem of these experiments is the overlapping of the tensor powder pattern spectra of magnetically distinct sites which cannot be resolved. In this work, high resolution NMR of hydrogen and deuterium in solids is demonstrated. For both nuclei, the resonances are narrowed to obtain liquid-like isotropic spectra by high frequency rotation of the sample about an axis inclined at the magic angle, ..beta../sub m/ = Arccos (3/sup -1/2/), with respect to the direction of the external magnetic field. For deuterium, the powder spectra were narrowed by over three orders of magnitude by magic angle rotation with precise control of ..beta... A second approach was the observation of deuterium double quantum transitions under magic angle rotation. For hydrogen, magic angle rotation alone could be applied to obtain the isotropic spectrum when H/sub D/ was small. This often occurs naturally when the nuclei are semi-dilute or involved in internal motion. In the general case of large H/sub D/, isotropic spectra were obtained by dilution of /sup 1/H with /sup 2/H combined with magic angle rotation. The resolution obtained represents the practical limit for proton NMR of solids.

  8. Hydrogen-deuterium substitution in solid ethanol by surface reactions at low temperatures

    NASA Astrophysics Data System (ADS)

    Oba, Yasuhiro; Osaka, Kazuya; Chigai, Takeshi; Kouchi, Akira; Watanabe, Naoki

    2016-10-01

    Ethanol (CH3CH2OH) is one of the most abundant complex organic molecules in star-forming regions. Despite its detection in the gas phase only, ethanol is believed to be formed by low-temperature grain-surface reactions. Methanol, the simplest alcohol, has been a target for observational, experimental, and theoretical studies in view of its deuterium enrichment in the interstellar medium; however, the deuterium chemistry of ethanol has not yet been an area of focus. Recently, deuterated dimethyl ether, a structural isomer of ethanol, was found in star-forming regions, indicating that deuterated ethanol can also be present in those environments. In this study, we performed laboratory experiments on the deuterium fractionation of solid ethanol at low temperatures through a reaction with deuterium (D) atoms at 10 K. Hydrogen (H)-D substitution, which increases the deuteration level, was found to occur on the ethyl group but not on the hydroxyl group. In addition, when deuterated ethanol (e.g. CD3CD2OD) solid was exposed to H atoms at 10 K, D-H substitution that reduced the deuteration level occurred on the ethyl group. Based on the results, it is likely that deuterated ethanol is present even under H-atom-dominant conditions in the interstellar medium.

  9. Electron Spin Relaxation in Irradiated Solids.

    DTIC Science & Technology

    1996-03-01

    the development and use of ELDOR techniques to study the spectral diffusion in irradiated L-alanine and other irradiated organic solids. Pulsed STELDOR...and pulsed two-frequency ELDOR methods were developed and the details of the implementation is reported. The assignment of relaxation times that gave

  10. Atomistic simulations of deuterium irradiation on iron-based alloys in future fusion reactors

    DOE PAGES

    Safi, E.; Polvi, J.; Lasa, A.; ...

    2016-10-14

    Iron-based alloys are now being considered as plasma-facing materials for the first wall of future fusion reactors. Therefore, the iron (Fe) and carbon (C) erosion will play a key role in predicting the life-time and viability of reactors with steel walls. In this work, the surface erosion and morphology changes due to deuterium (D) irradiation in pure Fe, Fe with 1% C impurity and the cementite, are studied using molecular dynamics (MD) simulations, varying surface temperature and impact energy. The sputtering yields for both Fe and C were found to increase with incoming energy. In iron carbide, C sputtering wasmore » preferential to Fe and the deuterium was mainly trapped as D2 in bubbles, while mostly atomic D was present in Fe and Fe–1%C. The sputtering yields obtained from MD were compared to SDTrimSP yields. At lower impact energies, the sputtering mechanism was of both physical and chemical origin, while at higher energies (>100 eV) the physical sputtering dominated.« less

  11. Atomistic simulations of deuterium irradiation on iron-based alloys in future fusion reactors

    SciTech Connect

    Safi, E.; Polvi, J.; Lasa, A.; Nordlund, K.

    2016-10-14

    Iron-based alloys are now being considered as plasma-facing materials for the first wall of future fusion reactors. Therefore, the iron (Fe) and carbon (C) erosion will play a key role in predicting the life-time and viability of reactors with steel walls. In this work, the surface erosion and morphology changes due to deuterium (D) irradiation in pure Fe, Fe with 1% C impurity and the cementite, are studied using molecular dynamics (MD) simulations, varying surface temperature and impact energy. The sputtering yields for both Fe and C were found to increase with incoming energy. In iron carbide, C sputtering was preferential to Fe and the deuterium was mainly trapped as D2 in bubbles, while mostly atomic D was present in Fe and Fe–1%C. The sputtering yields obtained from MD were compared to SDTrimSP yields. At lower impact energies, the sputtering mechanism was of both physical and chemical origin, while at higher energies (>100 eV) the physical sputtering dominated.

  12. Amorphization of solids irradiated by fast neutrons

    NASA Astrophysics Data System (ADS)

    Parkhomenko, V.; Dubinin, S.; Teploukhov, S.; Goshchitskii, B.

    2000-03-01

    The diffraction patterns of amorphous solids produced by both a conventional technique and fast neutron irradiation were systematized. It is shown for the first time that neutron radiation-modified solids belong to the group of amorphous substances of a distortion type.

  13. The deuterium/hydrogen distribution in chondritic organic matter attests to early ionizing irradiation

    PubMed Central

    Laurent, Boris; Roskosz, Mathieu; Remusat, Laurent; Robert, François; Leroux, Hugues; Vezin, Hervé; Depecker, Christophe; Nuns, Nicolas; Lefebvre, Jean-Marc

    2015-01-01

    Primitive carbonaceous chondrites contain a large array of organic compounds dominated by insoluble organic matter (IOM). A striking feature of this IOM is the systematic enrichment in deuterium compared with the solar hydrogen reservoir. This enrichment has been taken as a sign of low-temperature ion-molecule or gas-grain reactions. However, the extent to which Solar System processes, especially ionizing radiation, can affect D/H ratios is largely unknown. Here, we report the effects of electron irradiation on the hydrogen isotopic composition of organic precursors containing different functional groups. From an initial terrestrial composition, overall D-enrichments and differential intramolecular fractionations comparable with those measured in the Orgueil meteorite were induced. Therefore, ionizing radiation can quantitatively explain the deuteration of organics in some carbonaceous chondrites. For these meteorites, the precursors of the IOM may have had the same isotopic composition as the main water reservoirs of the inner Solar System. PMID:26461170

  14. Speed of sound in solid molecular hydrogen-deuterium: Quantum Molecular Dynamics Approximation

    NASA Astrophysics Data System (ADS)

    Guerrero, Carlo Luis; Perlado, Jose Manuel

    2016-05-01

    Uniformity of the solid layer is one of the critical points for an efficient ignition of the Deuterium-Tritium (DT) target. During the compression process this layer, perturbations grow as the Rayleigh-Taylor instability. Knowing the mechanical properties of this layer and its thermo-mechanical limits is necessary if we want to control or to minimize these instabilities. In this work we have used a simplified approach, replacing the DT ice system with a mixture of hydrogen-deuterium (HD) because beta decay of tritium complicates the analysis in the former case. Through simulation with ab initio methods we have calculated the elastic constants, the bulk modulus and sound velocity for hydrogen isotopes in solid molecular state. In this work we present the results for hydrogen-deuterium mixtures 50%-50%, at 15 K and with a compression which covers the range of 1 to 15 GPa. This system is interesting for study the early stages of the dynamic compression and provides conditions that are close to the manufacture of DT target in inertial confinement fusion. Discontinuities in the curve that have been observed on pure hydrogen, which are associated with phase transitions and the phase hysteresis.

  15. Influence of helium on deuterium retention in reduced activation ferritic martensitic steel (F82H) under simultaneous deuterium and helium irradiation

    NASA Astrophysics Data System (ADS)

    Yakushiji, K.; Lee, H. T.; Oya, M.; Hamaji, Y.; Ibano, K.; Ueda, Y.

    2016-02-01

    Deuterium and helium retention in Japanese reduced activation ferritic martensitic (RAFM) steel (F82H) under simultaneous D-He irradiation at 500, 625, 750, and 818 K was studied. This study aims to clarify tritium retention behavior in RAFM steels to assess their use as plasma facing materials. The irradiation fluence was kept constant at 1 × 1024 D m-2. Four He desorption peaks were observed with He retention greatest at 625 K. At T > 625 K a monotonic decrease in He retention was observed. At all temperatures a systematic reduction in D retention was observed for the simultaneous D-He case in comparison to D-only case. This suggests that He implanted at the near surface in RAFM steels may reduce the inward penetration of tritium in RAFM steels that would result in lower tritium inventory for a given fluence.

  16. Structural transformations in austenitic stainless steel induced by deuterium implantation: irradiation at 100 K

    NASA Astrophysics Data System (ADS)

    Morozov, Oleksandr; Zhurba, Volodymyr; Neklyudov, Ivan; Mats, Oleksandr; Rud, Aleksandr; Chernyak, Nikolay; Progolaieva, Viktoria

    2015-03-01

    Deuterium thermal desorption spectra were investigated on the samples of austenitic stainless steel 18Cr10NiTi preimplanted at 100 K with deuterium ions in the dose range from 3 × 1015 to 5 × 1018 D/cm2. The kinetics of structural transformation development in the implantation steel layer was traced from deuterium thermodesorption spectra as a function of implanted deuterium concentration. At saturation of austenitic stainless steel 18Cr10NiTi with deuterium by means of ion implantation, structural-phase changes take place, depending on the dose of implanted deuterium. The maximum attainable concentration of deuterium in steel is C = 1 (at.D/at.met. = 1/1). The increase in the implanted dose of deuterium is accompanied by the increase in the retained deuterium content, and as soon as the deuterium concentration attains C ≈ 0.5 the process of shear martensitic structural transformation in steel takes place. It includes the formation of bands, body-centered cubic (bcc) crystal structure, and the ferromagnetic phase. Upon reaching the deuterium concentration C > 0.5, the presence of these molecules causes shear martensitic structural transformations in the steel, which include the formation of characteristic bands, bcc crystal structure, and the ferromagnetic phase. At C ≥ 0.5, two hydride phases are formed in the steel, the decay temperatures of which are 240 and 275 K. The hydride phases are formed in the bcc structure resulting from the martensitic structural transformation in steel.

  17. A Deuterium NMR Spectroscopic Study of Solid BH(3)NH(3).

    PubMed

    Penner, Glenn H.; Chang, Y. C. Phillis; Hutzal, Jennifer

    1999-06-14

    Deuterium nuclear magnetic resonance (NMR) powder spectra and spin-lattice relaxation times (T(1)) are used to measure the deuterium quadrupolar coupling constants (QCCs) chi(BD) and chi(ND) and to investigate the molecular reorientation of the BD(3) and ND(3) groups in solid deuterated borane monoammoniate, BD(3)NH(3) and BH(3)ND(3), respectively. In the high-temperature, tetragonal, phase (above 225 K) the following Arrhenius parameters are obtained from the temperature-dependent T(1): E(a) = 5.9 +/- 0.5 kJ/mol and tau(infinity) = 1.1 x 10(-)(13) s for BD(3)NH(3); E(a) = 7.3 +/- 0.8 kJ/mol and tau(infinity) = 4.4 x 10(-)(14) s for BH(3)ND(3). In the low-temperature, orthorhombic, phase the following parameters are obtained: E(a) = 26.4 +/- 1.4 kJ/mol and tau(infinity) = 1.2 x 10(-)(17) s for BD(3)NH(3); E(a) = 13.7 +/- 0.9 kJ/mol and tau(infinity) = 5.7 x 10(-)(15) s for BH(3)ND(3). Here tau(infinity) is proportional to the inverse of the usual Arrhenius preexponential factor, A. Deuterium line shape measurements for the low-temperature phase of BD(3)NH(3) yield E(a) = 25 +/- 2 kJ/mol and tau(infinity) = 4.7 x 10(-)(19) s. These dynamic factors indicate that the molecule is probably undergoing whole molecule rotation above the phase transition but the BH(3) and NH(3) groups are undergoing uncorrelated motion in the low-temperature phase. Deuterium quadrupolar coupling constants of 105 +/- 10 and 200 +/- 10 kHz were determined for BD(3)NH(3) and BH(3)ND(3), respectively. Molecular orbital (MO) calculations (CI(SD)/6-31G(d,p)//MP2/6-31G(d,p)) for the isolated molecule yield values of 143 and 255 kHz. MO calculations also show that the deuterium quadrupolar coupling constants chi(BD) and chi(ND) are relatively insensitive to all molecular structural parameters except the B-H and N-H bond lengths, respectively. It is suggested that the large decrease in the QCC on going from the gas phase to the solid state may be due to a slight lengthening of the B-H and N-H bonds

  18. Solid Deuterium-Tritium Surface Roughness In A Beryllium Inertial Confinement Fusion Shell

    SciTech Connect

    Kozioziemski, B J; Sater, J D; Moody, J D; Montgomery, D S; Gautier, C

    2006-04-19

    Solid deuterium-tritium (D-T) fuel layers for inertial confinement fusion experiments were formed inside of a 2 mm diameter beryllium shell and were characterized using phase-contrast enhanced x-ray imaging. The solid D-T surface roughness is found to be 0.4 {micro}m for modes 7-128 at 1.5 K below the melting temperature. The layer roughness is found to increase with decreasing temperature, in agreement with previous visible light characterization studies. However, phase-contrast enhanced x-ray imaging provides a more robust surface roughness measurement than visible light methods. The new x-ray imaging results demonstrate clearly that the surface roughness decreases with time for solid D-T layers held at 1.5 K below the melting temperature.

  19. A combined deuterium NMR and quantum chemical investigation of inequivalent hydrogen bonds in organic solids.

    PubMed

    Webber, Renee; Penner, Glenn H

    2012-01-01

    Deuterium magic angle spinning (MAS) NMR spectroscopy and quantum chemical calculations are used to investigate organic solids in which inequivalent hydrogen bonds are present. The use of (2)H MAS allows one to measure the chemical shift, δ, quadrupolar coupling constant, C(Q), and asymmetry in the quadrupolar interaction, η(Q), for each type of hydrogen bond present in the system. Quantum chemical calculations of the magnetic shielding (σ, which can be related to δ) and the electric field gradient (EFG, which can be related to C(Q)) are compared to the experimental results and are discussed with respect to the relative strengths of the hydrogen bonds within each system.

  20. Proton or Deuteron Transfer in Phase IV of Solid Hydrogen and Deuterium

    NASA Astrophysics Data System (ADS)

    Liu, Hanyu; Ma, Yanming

    2013-01-01

    The recent discovery of phase IV of solid hydrogen and deuterium consisting of two alternate layers of graphenelike three-molecule rings and unbound H2 molecules have generated great interest. However, the vibrational nature of phase IV remains poorly understood. Here, we report a peculiar proton or deuteron transfer and a simultaneous rotation of three-molecule rings in graphenelike layers predicted by ab initio variable-cell molecular dynamics simulations for phase IV of solid hydrogen and deuterium at pressure ranges of 250-350 GPa and temperature range of 300-500 K. This proton or deuteron transfer is intimately related to the particular elongation of molecules in graphenelike layers, and it becomes more pronounced with increasing pressure at the course of larger elongation of molecules. As the consequence of proton transfer, hydrogen molecules in graphenelike layers are short lived and hydrogen vibration is strongly anharmonic. Our findings provide direct explanations on the observed abrupt increase of Raman width at the formation of phase IV and its large increase with pressure.

  1. Structural transformations in austenitic stainless steel induced by deuterium implantation: irradiation at 100 K.

    PubMed

    Morozov, Oleksandr; Zhurba, Volodymyr; Neklyudov, Ivan; Mats, Oleksandr; Rud, Aleksandr; Chernyak, Nikolay; Progolaieva, Viktoria

    2015-01-01

    Deuterium thermal desorption spectra were investigated on the samples of austenitic stainless steel 18Cr10NiTi preimplanted at 100 K with deuterium ions in the dose range from 3 × 10(15) to 5 × 10(18) D/cm(2). The kinetics of structural transformation development in the implantation steel layer was traced from deuterium thermodesorption spectra as a function of implanted deuterium concentration. At saturation of austenitic stainless steel 18Cr10NiTi with deuterium by means of ion implantation, structural-phase changes take place, depending on the dose of implanted deuterium. The maximum attainable concentration of deuterium in steel is C = 1 (at.D/at.met. = 1/1). The increase in the implanted dose of deuterium is accompanied by the increase in the retained deuterium content, and as soon as the deuterium concentration attains C ≈ 0.5 the process of shear martensitic structural transformation in steel takes place. It includes the formation of bands, body-centered cubic (bcc) crystal structure, and the ferromagnetic phase. Upon reaching the deuterium concentration C > 0.5, the presence of these molecules causes shear martensitic structural transformations in the steel, which include the formation of characteristic bands, bcc crystal structure, and the ferromagnetic phase. At C ≥ 0.5, two hydride phases are formed in the steel, the decay temperatures of which are 240 and 275 K. The hydride phases are formed in the bcc structure resulting from the martensitic structural transformation in steel.

  2. Magnetohydrodynamic simulation of solid-deuterium-initiated Z-pinch experiments

    SciTech Connect

    Sheehey, Peter Trogdon

    1994-02-01

    Solid-deuterium-initiated Z-pinch experiments are numerically simulated using a two-dimensional resistive magnetohydrodynamic model, which includes many important experimental details, such as ``cold-start`` initial conditions, thermal conduction, radiative energy loss, actual discharge current vs. time, and grids of sufficient size and resolution to allow realistic development of the plasma. The alternating-direction-implicit numerical technique used meets the substantial demands presented by such a computational task. Simulations of fiber-initiated experiments show that when the fiber becomes fully ionized rapidly developing m=0 instabilities, which originated in the coronal plasma generated from the ablating fiber, drive intense non-uniform heating and rapid expansion of the plasma column. The possibility that inclusion of additional physical effects would improve stability is explored. Finite-Larmor-radius-ordered Hall and diamagnetic pressure terms in the magnetic field evolution equation, corresponding energy equation terms, and separate ion and electron energy equations are included; these do not change the basic results. Model diagnostics, such as shadowgrams and interferograms, generated from simulation results, are in good agreement with experiment. Two alternative experimental approaches are explored: high-current magnetic implosion of hollow cylindrical deuterium shells, and ``plasma-on-wire`` (POW) implosion of low-density plasma onto a central deuterium fiber. By minimizing instability problems, these techniques may allow attainment of higher temperatures and densities than possible with bare fiber-initiated Z-pinches. Conditions for significant D-D or D-T fusion neutron production may be realizable with these implosion-based approaches.

  3. Helium and deuterium irradiation effects in W-Ta composites produced by pulse plasma compaction

    NASA Astrophysics Data System (ADS)

    Dias, M.; Catarino, N.; Nunes, D.; Fortunato, E.; Nogueira, I.; Rosinki, M.; Correia, J. B.; Carvalho, P. A.; Alves, E.

    2017-08-01

    Tungsten-tantalum composites have been envisaged for first-wall components of nuclear fusion reactors; however, changes in their microstructure are expected from severe irradiation with helium and hydrogenic plasma species. In this study, composites were produced from ball milled W powder mixed with 10 at.% Ta fibers through consolidation by pulse plasma compaction. Implantation was carried out at room temperature with He+ (30 keV) or D+ (15 keV) or sequentially with He+ and D+ using ion beams with fluences of 5 × 1021 at/m2. Microstructural changes and deuterium retention in the implanted composites were investigated by scanning electron microscopy, coupled with focused ion beam and energy dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Rutherford backscattering spectrometry and nuclear reaction analysis. The composite materials consisted of Ta fibers dispersed in a nanostructured W matrix, with Ta2O5 layers at the interfacial regions. The Ta and Ta2O5 surfaces exhibited blisters after He+ implantation and subsequent D+ implantation worsened the blistering behavior of Ta2O5. Swelling was also pronounced in Ta2O5 where large blisters exhibited an internal nanometer-sized fuzz structure. Transmission electron microscopy revealed an extensive presence of dislocations in the metallic phases after the sequential implantation, while a relatively low density of defects was detected in Ta2O5. This behavior may be partially justified by a shielding effect from the blisters and fuzz structure developed progressively during implantation. The tungsten peaks in the X-ray diffractograms were markedly shifted after He+ implantation, and even more so after the sequential implantation, which is in agreement with the increased D retention inferred from nuclear reaction analysis.

  4. Precursors to cold fusion phenomenon and the detection of energetic charged particles in deuterium/solid systems

    SciTech Connect

    Dong, S.Y.; Wang, K.L.; Feng, Y.Y.; Chang, L.; Luo, C.M.; Hu, R.Y.; Zhou, P.L.; Mo, D.W.; Zhu, Y.F.; Song, C.L.; Chen, Y.T.; Yao, M.Y.; Ren, C.; Chen, Q.K.; Li, X.Z. )

    1991-11-01

    A precursor to the cold fusion phenomenon in deuterium/solid systems is sought in order to solve the problem of reproducibility. The results of the first experiments are discussed. Electromagnetic radiation and energetic charged particles have been detected. In this paper it is shown that the surface condition has an important effect on this phenomenon.

  5. [Solid state isotope hydrogen exchange for deuterium and tritium in human gene-engineered insulin].

    PubMed

    Zolotarev, Yu A; Dadayan, A K; Kozik, V S; Gasanov, E V; Nazimov, I V; Ziganshin, R Kh; Vaskovsky, B V; Murashov, A N; Ksenofontov, A L; Haribin, O N; Nikolaev, E N; Myasoedov, N F

    2014-01-01

    The reaction of high temperature solid state catalytic isotope exchange in peptides and proteins under the action of catalyst-activated spillover hydrogen was studied. The reaction of human gene-engineered insulin with deuterium and tritium was conducted at 120-140° C to produce insulin samples containing 2-6 hydrogen isotope atoms. To determine the distribution of the isotope label over tritium-labeled insulin's amino acid residues, oxidation of the S-S bonds of insulin by performic acid was performed and polypeptide chains isolated; then their acid hydrolysis, amino acid analysis and liquid scintillation counts of tritium in the amino acids were conducted. The isotope label was shown to be incorporated in all amino acids of the protein, with the peptide fragment FVNQHLCGSHLVE of the insulin β-chain showing the largest incorporation. About 45% of the total protein isotope label was incorporated in His5 and His10 of this fragment. For the analysis of isotope label distribution in labeled insulin's peptide fragments, the recovery of the S-S bonds by mercaptoethanol, the enzymatic hydrolysis by glutamyl endopeptidase from Bacillus intermedius and HPLC division of the resulting peptides were carried out. Attribution of the peptide fragments formed due to hydrolysis at the Glu-X bond in the β-chain was accomplished by mass spectrometry. Mass spectrometry analysis data of the deuterium-labeled insulin samples' isotopomeric composition showed that the studied solid state isotope exchange reaction equally involved all the protein molecules. Biological studying of tritium-labeled insulin showed its physiological activity to be completely retained.

  6. Protein Conformation in Amorphous Solids by FTIR and by Hydrogen/Deuterium Exchange with Mass Spectrometry

    PubMed Central

    Sinha, Sandipan; Li, Yunsong; Williams, Todd D.; Topp, Elizabeth M.

    2008-01-01

    Solid-state hydrogen/deuterium exchange (ssHDX) with electrospray ionization mass spectrometry (ESI-MS) and Fourier transform infrared (FTIR) spectroscopy were used to assess protein conformation in amorphous solids. Myoglobin, lysozyme, β-lactoglobulin, ribonuclease A, E-cadherin 5, and concanavalin A were co-lyophilized with carbohydrates (trehalose, raffinose, and dextran 5000), linear polymers (polyvinyl alcohol and polyvinyl pyrrolidone) or guanidine hydrochloride (negative control). For ssHDX, samples were exposed to D2O vapor at 33% relative humidity and room temperature, and then reconstituted at low temperature (4°C) and pH 2.5 and analyzed by ESI-MS. Peptic digestion of selected proteins was used to provide region-specific information on exchange. FTIR spectra were acquired using attenuated total reflectance. FTIR and ssHDX of intact proteins showed preservation of structure by raffinose and trehalose, as indicated by FTIR band intensity and protection from exchange. ssHDX of peptic digests further indicated that these protective effects were not exerted uniformly along the protein sequence but were observed primarily in α-helical regions, a level of structural resolution not afforded by FTIR. The results thus demonstrate the utility of HDX with ESI-MS for analyzing protein conformation in amorphous solid samples. PMID:18835903

  7. Investigation of Rhodopsin Dynamics in its Signaling State by Solid-State Deuterium NMR Spectroscopy

    PubMed Central

    Struts, Andrey V.; Chawla, Udeep; Perera, Suchithranga M.D.C.; Brown, Michael F.

    2017-01-01

    Site-directed deuterium NMR spectroscopy is a valuable tool to study the structural dynamics of biomolecules in cases where solution NMR is inapplicable. Solid-state 2H NMR spectral studies of aligned membrane samples of rhodopsin with selectively labeled retinal provide information on structural changes of the chromophore in different protein states. In addition, solid-state 2H NMR relaxation time measurements allow one to study the dynamics of the ligand during the transition from the inactive to the active state. Here we describe the methodological aspects of solid-state 2H NMR spectroscopy for functional studies of rhodopsin, with an emphasis on the dynamics of the retinal cofactor. We provide complete protocols for the preparation of NMR samples of rhodopsin with 11-cis-retinal selectively deuterated at the methyl groups in aligned membranes. In addition, we review optimized conditions for trapping the rhodopsin photointermediates; and lastly we address the challenging problem of trapping the signaling state of rhodopsin in aligned membrane films. PMID:25697522

  8. Interaction of atomic and low-energy deuterium with tungsten pre-irradiated with self-ions

    SciTech Connect

    Ogorodnikova, O. V.; Markelj, S.; Toussaint, U. von

    2016-02-07

    Polycrystalline tungsten (W) specimens were pre-irradiated with self-ions to create identical samples with high density of defects up to ∼2.5 μm near the surface. Then, W specimens were exposed to either thermal atomic deuterium (D) beam with an incident energy of ∼0.2 eV or low energy D plasma with the incident energy varied between 5 and 200 eV at different sample temperatures. Each sample was exposed once at certain temperature and fluence. The D migration and accumulation in W were studied post-mortem by nuclear reaction method. It was shown that the rate of the D to occupy radiation-induced defects increases with increasing the incident energy, ion flux, and temperature. Experimental investigation was accompanied by modelling using the rate-equation model. Moreover, the analytical model was developed and benchmarked against numerical model. The calculations of the deuterium diffusion with trapping at radiation-induced defects in tungsten by analytical model are consistent with numerical calculations using rate-equation model. The data of reflection and penetration of atomic and low-energy D were taking from calculations using molecular dynamics (MD) with Juslin interatomic potentials and a binary collision code TRIM. MD calculations show an agreement with a binary collision code TRIM only in a very narrow range of deuterium energies between 1 and 20 eV. Incorporation of the data of reflection and penetration of deuterium in the macroscopic modelling has been done to verify the range of validity of calculations using MD and binary collision code TRIM by comparison of modelling results with experimental data. Modelling results are consistent with experiments using reflection and penetration data of D obtained from TRIM code for incident ion energy above 1 eV. Otherwise, the parameters obtained from MD should be incorporated in the rate-equation model to have a good agreement with the experiments.

  9. Sputtering of lithiated and oxidated carbon surfaces by low-energy deuterium irradiation

    NASA Astrophysics Data System (ADS)

    Domínguez-Gutiérrez, F. J.; Krstić, P. S.

    2017-08-01

    We study sputtering of lithiated and oxidized amorphous carbon surfaces by deuterium impact in energy range 5-30 eV. Using classical molecular dynamics, we obtain the sputtering yield, the mass and energy spectra, as well as the angular distribution of ejected atoms and molecules of the surfaces saturated by accumulated deuterium impacts. Our results are compared with existing experimental and theoretical data for amorphous a-C:D surfaces, showing that presence of lithium reduces erosion of carbon, while oxygen further enhances this effect.

  10. Nuclear reactions in deuterium-saturated palladium under irradiation by 10 MeV γ-quanta, in dense molecular deuterium at 1.2 kbar pressure

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wisniewski, R. S.

    2013-08-01

    A high-pressure chamber with a Pd-rod inside was filled up with 1.2 kbar molecular deuterium (DHPC). Then the saturated by deuterium palladium rod was irradiated during 18 hours by 11 MeV braking γ-quanta at 11-13 μA electron beam using the MT-25 electron accelerator. The element compositions of all the DHPC surfaces which had been in contact with dense deuterium gas were studied using scanning electronic microscopes with Roentgen microprobe analysis. It was determined that all the surfaces, including surfaces of the high-purity Pd-rod (99.995%), were covered either by a partially homogeneous layer or large microparticles of lead. Also, light elements as C, O, Na, Mg, Al, Si, Ti, Mn, Fe, Cu, Zn and heavy metals as Ag, Ta, W, Pt, Au and Pb were observed on the chambers inner surfaces.

  11. Performance of the Los Alamos National Laboratory spallation-driven solid-deuterium ultra-cold neutron source.

    PubMed

    Saunders, A; Makela, M; Bagdasarova, Y; Back, H O; Boissevain, J; Broussard, L J; Bowles, T J; Carr, R; Currie, S A; Filippone, B; García, A; Geltenbort, P; Hickerson, K P; Hill, R E; Hoagland, J; Hoedl, S; Holley, A T; Hogan, G; Ito, T M; Lamoreaux, Steve; Liu, Chen-Yu; Liu, J; Mammei, R R; Martin, J; Melconian, D; Mendenhall, M P; Morris, C L; Mortensen, R N; Pattie, R W; Pitt, M; Plaster, B; Ramsey, J; Rios, R; Sallaska, A; Seestrom, S J; Sharapov, E I; Sjue, S; Sondheim, W E; Teasdale, W; Young, A R; VornDick, B; Vogelaar, R B; Wang, Z; Xu, Yanping

    2013-01-01

    In this paper, we describe the performance of the Los Alamos spallation-driven solid-deuterium ultra-cold neutron (UCN) source. Measurements of the cold neutron flux, the very low energy neutron production rate, and the UCN rates and density at the exit from the biological shield are presented and compared to Monte Carlo predictions. The cold neutron rates compare well with predictions from the Monte Carlo code MCNPX and the UCN rates agree with our custom UCN Monte Carlo code. The source is shown to perform as modeled. The maximum delivered UCN density at the exit from the biological shield is 52(9) UCN/cc with a solid deuterium volume of ~1500 cm(3).

  12. Performance of the Los Alamos National Laboratory spallation-driven solid-deuterium ultra-cold neutron source

    SciTech Connect

    Saunders, A.; Makela, M.; Bagdasarova, Y.; Boissevain, J.; Bowles, T. J.; Currie, S. A.; Hill, R. E.; Hogan, G.; Morris, C. L.; Mortensen, R. N.; Ramsey, J.; Seestrom, S. J.; Sondheim, W. E.; Teasdale, W.; Wang, Z.; Back, H. O.; Broussard, L. J.; Hoagland, J.; Holley, A. T.; Pattie, R. W. Jr.; and others

    2013-01-15

    In this paper, we describe the performance of the Los Alamos spallation-driven solid-deuterium ultra-cold neutron (UCN) source. Measurements of the cold neutron flux, the very low energy neutron production rate, and the UCN rates and density at the exit from the biological shield are presented and compared to Monte Carlo predictions. The cold neutron rates compare well with predictions from the Monte Carlo code MCNPX and the UCN rates agree with our custom UCN Monte Carlo code. The source is shown to perform as modeled. The maximum delivered UCN density at the exit from the biological shield is 52(9) UCN/cc with a solid deuterium volume of {approx}1500 cm{sup 3}.

  13. Changes of surface structure and elemental composition of components of deuterium high-pressure chamber with Pd rod inside irradiated with 10-MeV γ-quanta in dense deuterium gas

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wiśniewski, R.; Wilczynska-Kitowska, T.

    2013-12-01

    This work is a continuation and addition to Ref. [1], which presents results on studies of the surface and elemental compositions of a Pd rod and brass screw for the collection of nuclear and chemical reaction products in a deuterium high-pressure chamber (DHPC) under irradiation with γ-quanta with an energy of 10 MeV for 18 h at the MT-25 electron accelerator at a beam current of 11-13 μA. The DHPC is filled with 1.2-kbar molecular deuterium in which a Pd rod saturated with deuterium is loaded. After irradiation, the elemental compositions of other surfaces of all DHPC elements, which are inside the DHPC in dense deuterium, are studied using an electron scanning microscope and X-ray microprobe analysis. It is established that all surfaces, including the surface of a high-purity palladium rod (99.995%), are covered with a partly homogeneous layer of large microparticles of lead. Also, light elements such as 6C, 8O, 11Na, 12Mg, 13Al, 14Si, 22Ti, 25Mn, 26Fe, 29Cu, and 30Zn and heavy metals such as 47Ag, 73Ta, 74W, 78Pt, 79Au, and 82Pb are observed. Possible processes that can cause the anomalies observed in the new synthesized elements are briefly discussed.

  14. Sandis irradiator for dried sewage solids. Final safety analysis report

    SciTech Connect

    Morris, M.

    1980-07-01

    Analyses of the hazards associated with the operation of the Sandia irradiator for dried sewage solids, as well as methods and design considerations to minimize these hazards, are presented in accordance with DOE directives.

  15. Discovery of temperature-dependent phenomena of muon-catalyzed fusion in solid deuterium and tritium mixtures.

    PubMed

    Kawamura, N; Nagamine, K; Matsuzaki, T; Ishida, K; Nakamura, S N; Matsuda, Y; Tanase, M; Kato, M; Sugai, H; Kudo, K; Takeda, N; Eaton, G H

    2003-01-31

    A systematic experimental study on muon-catalyzed fusion was conducted using a series of solid deuterium and tritium mixtures. A variety of conditions were investigated, i.e., tritium concentrations from 20% to 70%, and temperatures from 5 to 16 K. With decreasing temperature, we observed an unexpected decrease in the muon cycling rate (lambda(c)) and an increase in the muon loss probability (W). The origins of these observed changes were interpreted by the temperature-dependence in the dt mu formation process for lambda(c) and that in the muon reactivation process after muon-to-alpha sticking for W.

  16. Results of irradiating aluminum and homogeneous alloy YMn2 by 23 MeV γ-quanta in a molecular deuterium atmosphere at 2 kbar pressure

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wisniewski, R.

    2014-03-01

    Specimens of a number of metal were placed successively along the length in a deuterium high-pressure chamber of the "finger type" (DHPC-FT). The specimens were: two aluminum rods, a copper rod, two YMn2 alloy specimens, and stainless steel. The molecular deuterium pressure in the DHPC-FT chamber was 2 kbar. The specimens were irradiated by braking γ-quanta with boundary energy 23 MeV. After irradiation, all specimens were investigated on scanning electron microscopes (SEM) with electron probe X-ray microelement analysis (XMA). Considerable changes in the structure of the surfaces and elemental composition of the measured aluminum, destruction of the homogeneous YMn2 alloy specimen, and the "formation of monocrystalline specimens" of the YMn2 type and structures resembling manganese-based "crystals" were observed. A phenomenological explanation of the observed phenomena and effects based on nuclear reactions is proposed with consideration of certain new approaches, which are examined.

  17. Spectral properties of ion irradiated carbon rich solids

    NASA Astrophysics Data System (ADS)

    Strazzulla, G.; Baratta, G.; Brunetto, R.; Garozzo, M.; Kanuchova, Z.

    2009-04-01

    Carbon rich solid materials have been studied before, during, and after ion irradiation (3-400 keV ions) by in situ reflectance spectroscopy (from UV to IR). Frozen hydrocarbons (benzene, methane, butane, acetylene, etc., also mixed with water ice) have been irradiated at low temperature with fast ions. Irradiation causes the formation of many molecular species and of a long chain polymer like material (organic refractory residue). The process mimics what occurs in space because of cosmic ion irradiation of the icy surfaces of some objects in the Solar System. Other irradiated materials include natural bitumens (Asphaltite, kerite) and polymers (i.e. polystyrene). Upon irradiation the originally transparent polymer samples are converted in a material that, already at low doses, strongly absorbs in the UV. Such materials could mimic a kind of organic material (i.e. a spectrally neutral one) freshly exposed at the surface of minor objects in the Solar System because of meteoritic impact.

  18. Predicting Protein Aggregation during Storage in Lyophilized Solids Using Solid State Amide Hydrogen/Deuterium Exchange with Mass Spectrometric Analysis (ssHDX-MS)

    PubMed Central

    2015-01-01

    Solid state amide hydrogen/deuterium exchange with mass spectrometric analysis (ssHDX-MS) was used to assess the conformation of myoglobin (Mb) in lyophilized formulations, and the results correlated with the extent of aggregation during storage. Mb was colyophilized with sucrose (1:1 or 1:8 w/w), mannitol (1:1 w/w), or NaCl (1:1 w/w) or in the absence of excipients. Immediately after lyophilization, samples of each formulation were analyzed by ssHDX-MS and Fourier transform infrared spectroscopy (FTIR) to assess Mb conformation, and by dynamic light scattering (DLS) and size exclusion chromatography (SEC) to determine the extent of aggregation. The remaining samples were then placed on stability at 25 °C and 60% RH or 40 °C and 75% RH for up to 1 year, withdrawn at intervals, and analyzed for aggregate content by SEC and DLS. In ssHDX-MS of samples immediately after lyophilization (t = 0), Mb was less deuterated in solids containing sucrose (1:1 and 1:8 w/w) than in those containing mannitol (1:1 w/w), NaCl (1:1 w/w), or Mb alone. Deuterium uptake kinetics and peptide mass envelopes also indicated greater Mb structural perturbation in mannitol, NaCl, or Mb-alone samples at t = 0. The extent of deuterium incorporation and kinetic parameters related to rapidly and slowly exchanging amide pools (Nfast, Nslow), measured at t = 0, were highly correlated with the extent of aggregation on storage as measured by SEC. In contrast, the extent of aggregation was weakly correlated with FTIR band intensity and peak position measured at t = 0. The results support the use of ssHDX-MS as a formulation screening tool in developing lyophilized protein drug products. PMID:24816133

  19. Predicting protein aggregation during storage in lyophilized solids using solid state amide hydrogen/deuterium exchange with mass spectrometric analysis (ssHDX-MS).

    PubMed

    Moorthy, Balakrishnan S; Schultz, Steven G; Kim, Sherry G; Topp, Elizabeth M

    2014-06-02

    Solid state amide hydrogen/deuterium exchange with mass spectrometric analysis (ssHDX-MS) was used to assess the conformation of myoglobin (Mb) in lyophilized formulations, and the results correlated with the extent of aggregation during storage. Mb was colyophilized with sucrose (1:1 or 1:8 w/w), mannitol (1:1 w/w), or NaCl (1:1 w/w) or in the absence of excipients. Immediately after lyophilization, samples of each formulation were analyzed by ssHDX-MS and Fourier transform infrared spectroscopy (FTIR) to assess Mb conformation, and by dynamic light scattering (DLS) and size exclusion chromatography (SEC) to determine the extent of aggregation. The remaining samples were then placed on stability at 25 °C and 60% RH or 40 °C and 75% RH for up to 1 year, withdrawn at intervals, and analyzed for aggregate content by SEC and DLS. In ssHDX-MS of samples immediately after lyophilization (t = 0), Mb was less deuterated in solids containing sucrose (1:1 and 1:8 w/w) than in those containing mannitol (1:1 w/w), NaCl (1:1 w/w), or Mb alone. Deuterium uptake kinetics and peptide mass envelopes also indicated greater Mb structural perturbation in mannitol, NaCl, or Mb-alone samples at t = 0. The extent of deuterium incorporation and kinetic parameters related to rapidly and slowly exchanging amide pools (Nfast, Nslow), measured at t = 0, were highly correlated with the extent of aggregation on storage as measured by SEC. In contrast, the extent of aggregation was weakly correlated with FTIR band intensity and peak position measured at t = 0. The results support the use of ssHDX-MS as a formulation screening tool in developing lyophilized protein drug products.

  20. Optical damage assessment and recovery investigation of hydrogen-ion and deuterium-ion plasma-irradiated bulk ZnO single crystals

    NASA Astrophysics Data System (ADS)

    Empizo, Melvin John F.; Yamanoi, Kohei; Mori, Kazuyuki; Iwano, Keisuke; Iwasa, Yuki; Minami, Yuki; Arita, Ren; Fukuda, Kazuhito; Takano, Keisuke; Shimizu, Toshihiko; Nakajima, Makoto; Yoshimura, Masashi; Sarukura, Nobuhiko; Norimatsu, Takayoshi; Hangyo, Masanori; Azechi, Hiroshi; Fukuda, Tsuguo; Singidas, Bess G.; Sarmago, Roland V.; Oya, Makoto; Ueda, Yoshio

    2017-05-01

    In realizing zinc oxide (ZnO) scintillator applications, we assess the optical damage and investigate the recovery of hydrogen-ion (H-ion) and deuterium-ion (D-ion) plasma-irradiated bulk ZnO single crystals. Hydrothermal-grown bulk crystals are irradiated with H-ion and D-ion beams with 1 keV energy and ˜ 10 20 m - 2 s - 1 flux. After irradiation, the single crystals exhibit decreased visible transparencies, redshifted ultraviolet (UV) emission peaks, shortened UV emission lifetimes, and suppressed visible emission bands. These changes in the optical transmittances and photoluminescence emissions are attributed to the generation of defects during irradiation and to the interaction of hydrogen with other defects and/or impurities. Although modified by ion irradiation, the optical properties of the ZnO crystals, except for the UV emission lifetimes, recover hours after without any sample treatment and only at room temperature. Compared with the H-ion-irradiated sample, the D-ion-irradiated crystal has a slower recovery which may be related to the ions' masses, energy losses, and absolute diffusivities. Our results nevertheless show that bulk ZnO single crystals exhibit resistance to and recovery from H-ion and D-ion irradiation and can therefore be used as scintillator materials for radiation detectors inside future fusion reactors.

  1. Testing the performance of a cryogenic visualization system on thermal counterflow by using hydrogen and deuterium solid tracers.

    PubMed

    La Mantia, M; Chagovets, T V; Rotter, M; Skrbek, L

    2012-05-01

    An experimental apparatus has been designed to analyze by visualization cryogenic flows of liquid (4)He and consequently address unresolved problems of quantum turbulence. The newly implemented flow visualization setup is described and its specific features discussed. Thermal counterflow experiments have been performed and the motion of solid hydrogen and deuterium tracers studied by using the particle tracking velocimetry technique in order to probe the system capabilities. It is shown that the obtained results are consistent with the two-fluid model describing the behavior of superfluid (4)He. A number of technical and fundamental issues, such as particles' aggregation, role of rotating particles in counterflow and evidence of non-Gaussian distribution of tracers' velocities, are also discussed. The apparatus appears to be well-suited to the task of analyzing cryogenic flows and potentially capable of obtaining new results stimulating further understanding of the underlying physics.

  2. Chemical composition and structural phase changes of Pd sample and properties of novel synthesized structure at dense deuterium gas under irradiation by γ-quanta

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wiśniewski, R.

    2012-12-01

    Studies have been carried out into the element composition of Pd and brass with associated materials and synthesized novel structure, placed in dense deuterium gas in a deuterium high-pressure chamber (DHPC) under the pressure 3 kbar and irradiated with γ-quanta of energy up to 8.8 MeV. Using the methods of scanning electron microscopy, microelement chemical analysis and X-ray diffraction, it was determined that in the absence in the chamber volume and walls of all HPC-forming materials the synthesized structure is largely composed of alumosilicates and Al and Si oxides with high content of Ti compounds as rutile TiO2. Pd1.5D2. Considerable anomalies in the chemical composition were found both in the surface and at large depth in a Pd specimen. The entire Pd surface turned into a structure comprised of Pd clusters, Cu and Zn compounds, with a notable content of Mg, Al, S, Si, K, Ca, Ti and Fe compounds. Results of evaluative calculations, including computation of the Q-value, are presented for nuclear reactions produced in a saturated with deuterium Pd specimen and dense deuterium gas under the action of γ-quanta, neutrons and protons of energies up to E n + E p ≈ E γ - E D MeV generated by deuteron fission. The obtained results can be explained by "collective effects" as chain reactions caused by deuteron fission induced by protons ( E p > 3.39 MeV) and neutrons ( E n > 2.25 MeV), as well as by thermonuclear synthesis of deuterium atoms elastically scattered by protons of energies up to E P < E γ - E D MeV.

  3. Deuterium migration in nuclear graphite: Consequences for the behavior of tritium in CO2-cooled reactors and for the decontamination of irradiated graphite waste

    NASA Astrophysics Data System (ADS)

    Le Guillou, M.; Toulhoat, N.; Pipon, Y.; Moncoffre, N.; Khodja, H.

    2015-06-01

    In this paper, we aim at understanding tritium behavior in the graphite moderator of French CO2-cooled nuclear fission reactors (called UNGG for "Uranium Naturel-Graphite-Gaz") to get information on its distribution and inventory in the irradiated graphite waste after their dismantling. These findings should be useful both to improve waste treatment processes and to foresee tritium behavior during reactor decommissioning and waste disposal operations. The purpose of the present work is to elucidate the effects of temperature on the behavior of tritium during reactor operation. Furthermore, it aims at exploring options of thermal decontamination. For both purposes, annealing experiments were carried out in inert atmosphere as well as in thermal conditions as close as possible to those encountered in UNGG reactors and in view of a potential decontamination in humid gas. D+ ions were implanted into virgin nuclear graphite in order to simulate tritium displaced from its original structural site through recoil during reactor operation. The effect of thermal treatments on the mobility of the implanted deuterium was then investigated at temperatures ranging from 200 to 1200 °C, in inert atmosphere (vacuum or argon), in a gas simulating the UNGG coolant gas (mainly CO2) or in humid nitrogen. Deuterium was analyzed by Nuclear Reaction Analysis (NRA) both at millimetric and micrometric scales. We have identified three main stages for the deuterium release. The first one corresponds to deuterium permeation through graphite open pores. The second and third ones are controlled by the progressive detrapping of deuterium located at different trapping sites and its successive migration through the crystallites and along crystallites and coke grains edges. Extrapolating the thermal behavior of deuterium to tritium, the results show that the release becomes significant above the maximum UNGG reactor temperature of 500 °C and should be lower than 30% of the total amount produced

  4. Raman measurements of phase transitions in dense solid hydrogen and deuterium to 325 GPa

    PubMed Central

    Zha, Chang-sheng; Cohen, R. E.; Mao, Ho-kwang; Hemley, Russell J.

    2014-01-01

    Raman spectroscopy of dense hydrogen and deuterium performed to 325 GPa at 300 K reveals previously unidentified transitions. Detailed analysis of the spectra from multiple experimental runs, together with comparison with previous infrared and Raman measurements, provides information on structural modifications of hydrogen as a function of density through the I–III–IV transition sequence, beginning near 200 GPa at 300 K. The data suggest that the transition sequence at these temperatures proceeds by formation of disordered stacking of molecular and distorted layers. Weaker spectral changes are observed at 250, 285, and 300 GPa, that are characterized by discontinuities in pressure shifts of Raman frequencies, and changes in intensities and linewidths. The results indicate changes in structure and bonding, molecular orientational order, and electronic structure of dense hydrogen at these conditions. The data suggest the existence of new phases, either variations of phase IV, or altogether new structures. PMID:24639543

  5. Raman measurements of phase transitions in dense solid hydrogen and deuterium to 325 GPa.

    PubMed

    Zha, Chang-sheng; Cohen, R E; Mao, Ho-kwang; Hemley, Russell J

    2014-04-01

    Raman spectroscopy of dense hydrogen and deuterium performed to 325 GPa at 300 K reveals previously unidentified transitions. Detailed analysis of the spectra from multiple experimental runs, together with comparison with previous infrared and Raman measurements, provides information on structural modifications of hydrogen as a function of density through the I-III-IV transition sequence, beginning near 200 GPa at 300 K. The data suggest that the transition sequence at these temperatures proceeds by formation of disordered stacking of molecular and distorted layers. Weaker spectral changes are observed at 250, 285, and 300 GPa, that are characterized by discontinuities in pressure shifts of Raman frequencies, and changes in intensities and linewidths. The results indicate changes in structure and bonding, molecular orientational order, and electronic structure of dense hydrogen at these conditions. The data suggest the existence of new phases, either variations of phase IV, or altogether new structures.

  6. Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion.

    PubMed

    Tanabe, Katsuaki

    2016-01-01

    We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

  7. Dosimetry report for the Sandia irradiator for dried sewage solids

    SciTech Connect

    Greene, R.T.; McFarland, E.W.; Dickson, H.W.

    1981-06-01

    Gamma dose measurements were made at the Sandia Irradiator for Dried Sewage Solids. Passive plastic, chemical, and thermoluminescent dosimeters were exposed in the facility under conditions designed to simulate typical plant operation. Absolute dose and dose distribution information were obtained in air, water, compost, fruit, and sewage sludge.

  8. Irradiation-induced composition patterns in binary solid solutions

    SciTech Connect

    Dubey, Santosh; El-Azab, Anter

    2013-09-28

    A theoretical/computational model for the irradiation-driven compositional instabilities in binary solid solutions has been developed. The model is suitable for investigating the behavior of structural alloys and metallic nuclear fuels in a reactor environment as well as the response of alloy thin films to ion beam irradiation. The model is based on a set of reaction-diffusion equations for the dynamics of vacancies, interstitials, and lattice atoms under irradiation. The dynamics of these species includes the stochastic generation of defects by collision cascades as well as the defect reactions and diffusion. The atomic fluxes in this model are derived based on the transitions of lattice defects. The set of reaction-diffusion equations are stiff, hence a stiffly stable method, also known as the Gear method, has been used to numerically approximate the equations. For the Cu-Au alloy in the solid solution regime, the model results demonstrate the formation of compositional patterns under high-temperature particle irradiation, with Fourier space properties (Fourier spectrum, average wavelength, and wavevector) depending on the cascade damage characteristics, average composition, and irradiation temperature.

  9. Investigation of irradiation effects on highly integrated leading-edge electronic components of diagnostics and control systems for LHD deuterium operation

    NASA Astrophysics Data System (ADS)

    Ogawa, K.; Nishitani, T.; Isobe, M.; Murata, I.; Hatano, Y.; Matsuyama, S.; Nakanishi, H.; Mukai, K.; Sato, M.; Yokota, M.; Kobuchi, T.; Nishimura, T.; Osakabe, M.

    2017-08-01

    High-temperature and high-density plasmas are achieved by means of real-time control, fast diagnostic, and high-power heating systems. Those systems are precisely controlled via highly integrated electronic components, but can be seriously affected by radiation damage. Therefore, the effects of irradiation on currently used electronic components should be investigated for the control and measurement of Large Helical Device (LHD) deuterium plasmas. For the precise estimation of the radiation field in the LHD torus hall, the MCNP6 code is used with the cross-section library ENDF B-VI. The geometry is modeled on the computer-aided design. The dose on silicon, which is a major ingredient of electronic components, over nine years of LHD deuterium operation shows that the gamma-ray contribution is dominant. Neutron irradiation tests were performed in the OKTAVIAN at Osaka University and the Fast Neutron Laboratory at Tohoku University. Gamma-ray irradiation tests were performed at the Nagoya University Cobalt-60 irradiation facility. We found that there are ethernet connection failures of programmable logic controller (PLC) modules due to neutron irradiation with a neutron flux of 3  ×  106 cm-2 s-1. This neutron flux is equivalent to that expected at basement level in the LHD torus hall without a neutron shield. Most modules of the PLC are broken around a gamma-ray dose of 100 Gy. This is comparable with the dose in the LHD torus hall over nine years. If we consider the dose only, these components may survive more than nine years. For the safety of the LHD operation, the electronic components in the torus hall have been rearranged.

  10. High-resolution NMR of hydrogen in organic solids by DNP enhanced natural abundance deuterium spectroscopy.

    PubMed

    Rossini, Aaron J; Schlagnitweit, Judith; Lesage, Anne; Emsley, Lyndon

    2015-10-01

    We demonstrate that high field (9.4 T) dynamic nuclear polarization (DNP) at cryogenic (∼100 K) sample temperatures enables the rapid acquisition of natural abundance (1)H-(2)H cross-polarization magic angle spinning (CPMAS) solid-state NMR spectra of organic solids. Spectra were obtained by impregnating substrates with a solution of the stable DNP polarizing agent TEKPol in tetrachloroethane. Tetrachloroethane is a non-solvent for the solids, and the unmodified substrates are then polarized through spin diffusion. High quality natural abundance (2)H CPMAS spectra of histidine hydrochloride monohydrate, glycylglycine and theophylline were acquired in less than 2h, providing direct access to hydrogen chemical shifts and quadrupolar couplings. The spectral resolution of the (2)H solid-state NMR spectra is comparable to that of (1)H spectra obtained with state of the art homonuclear decoupling techniques. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  11. High-resolution NMR of hydrogen in organic solids by DNP enhanced natural abundance deuterium spectroscopy

    NASA Astrophysics Data System (ADS)

    Rossini, Aaron J.; Schlagnitweit, Judith; Lesage, Anne; Emsley, Lyndon

    2015-10-01

    We demonstrate that high field (9.4 T) dynamic nuclear polarization (DNP) at cryogenic (∼100 K) sample temperatures enables the rapid acquisition of natural abundance 1H-2H cross-polarization magic angle spinning (CPMAS) solid-state NMR spectra of organic solids. Spectra were obtained by impregnating substrates with a solution of the stable DNP polarizing agent TEKPol in tetrachloroethane. Tetrachloroethane is a non-solvent for the solids, and the unmodified substrates are then polarized through spin diffusion. High quality natural abundance 2H CPMAS spectra of histidine hydrochloride monohydrate, glycylglycine and theophylline were acquired in less than 2 h, providing direct access to hydrogen chemical shifts and quadrupolar couplings. The spectral resolution of the 2H solid-state NMR spectra is comparable to that of 1H spectra obtained with state of the art homonuclear decoupling techniques.

  12. Lattice vibrations of para-hydrogen impurities in a solid deuterium matrix: An inelastic neutron scattering study

    NASA Astrophysics Data System (ADS)

    Colognesi, D.; Celli, M.; Ramirez-Cuesta, A. J.; Zoppi, M.

    2007-11-01

    In the present study, we report inelastic neutron scattering measurements from para-hydrogen defects in solid normal deuterium at three different concentrations (between 3% and 11%) using the time-of-flight spectrometer TOSCA-II. The measured double-differential cross sections give access to the self-inelastic structure factors for the H2 centers of mass. Corrected experimental data, analyzed through the Young-Koppel model and the Gaussian approximation, are transformed into defect densities of phonon states, which come out to be broad, structured, and nearly concentration independent. Two experimentally determined Bose-corrected spectral moments are found to be in agreement with independent estimates, providing a strong validation of our data reduction procedure. Subsequently, experimental phonon spectra are compared to three calculations, namely, a simple harmonic model at infinite dilution, a more advanced harmonic model with concentration effects, and finally a lattice dynamics simulation based on self-consistent phonon and coherent potential approximations. However, while the first part of the defect spectral density, attributed to the propagating modes, turns out to be roughly explained, the localized part is properly described by none of these models, except for its mean frequency position. The large overall width appears so far impossible to be reproduced, representing a challenge for the physicists involved in quantum dynamics simulations.

  13. Liquid-solid phase transition of hydrogen and deuterium in silica aerogel

    NASA Astrophysics Data System (ADS)

    Van Cleve, E.; Worsley, M. A.; Kucheyev, S. O.

    2014-10-01

    Behavior of hydrogen isotopes confined in disordered low-density nanoporous solids remains essentially unknown. Here, we use relaxation calorimetry to study freezing and melting of H2 and D2 in an ˜85%-porous base-catalyzed silica aerogel. We find that liquid-solid transition temperatures of both isotopes inside the aerogel are depressed. The phase transition takes place over a wide temperature range of ˜4 K and non-trivially depends on the liquid filling fraction, reflecting the broad pore size distribution in the aerogel. Undercooling is observed for both H2 and D2 confined inside the aerogel monolith. Results for H2 and D2 are extrapolated to tritium-containing hydrogens with the quantum law of corresponding states.

  14. Liquid–solid phase transition of hydrogen and deuterium in silica aerogel

    SciTech Connect

    Van Cleve, E.; Worsley, M. A.; Kucheyev, S. O.

    2014-10-28

    Behavior of hydrogen isotopes confined in disordered low-density nanoporous solids remains essentially unknown. Here, we use relaxation calorimetry to study freezing and melting of H{sub 2} and D{sub 2} in an ∼85%-porous base-catalyzed silica aerogel. We find that liquid–solid transition temperatures of both isotopes inside the aerogel are depressed. The phase transition takes place over a wide temperature range of ∼4 K and non-trivially depends on the liquid filling fraction, reflecting the broad pore size distribution in the aerogel. Undercooling is observed for both H{sub 2} and D{sub 2} confined inside the aerogel monolith. Results for H{sub 2} and D{sub 2} are extrapolated to tritium-containing hydrogens with the quantum law of corresponding states.

  15. Structure and dynamics of retinal in rhodopsin elucidated by deuterium solid state NMR

    NASA Astrophysics Data System (ADS)

    Salgado, Gilmar Fernandes De Jesus

    Rhodopsin is a seven transmembrane helix GPCR found which mediates dim light vision, in which the binding pocket is occupied by the ligand 11- cis-retinal. A site-directed 2H-labeling approach utilizing solid-state 2H NMR spectroscopy was used to investigate the structure and dynamics of retinal within its binding pocket in the dark state of rhodopsin, and as well the MetaI and MetaII. 11-cis-[5-C 2H3]-, 11-cis-[9-C 2H3]-, and 11-cis-[13-C2H 3]-retinal were used to regenerate bleached rhodopsin. Recombinant membranes comprising purified rhodopsin and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) were prepared (1:50 molar ratio). Solid-state 2H NMR spectra were obtained for the aligned rhodopsin/POPC recombinant membranes at temperatures below the order-disorder phase transition temperature of POPC. The solid-state NMR studies of aligned samples, give the orientations of the 2H nuclear coupling tensor relative to the membrane frame, which involve both the conformation and orientation of the bound retinal chromophore. Theoretical simulations of the experimental 2H NMR spectra employed a new lineshape treatment for a semi-random distribution due to static uniaxial disorder. The analysis gives the orientation of the 2H-labeled C-C2H3 methyl bond axes relative to the membrane plane as well as the extent of three-dimensional alignment disorder (mosaic spread). These results clearly demonstrate the applicability of site-directed 2H NMR methods for investigating conformational changes and dynamics of ligands bound to rhodopsin and other GPCRs in relation to their characteristic mechanisms of action.

  16. Molecular collective dynamics in solid para-hydrogen and ortho-deuterium: The Parrinello-Rahman-type path integral centroid molecular dynamics approach

    NASA Astrophysics Data System (ADS)

    Saito, Hiroaki; Nagao, Hidemi; Nishikawa, Kiyoshi; Kinugawa, Kenichi

    2003-07-01

    The single-particle and collective dynamics of hydrogen/deuterium molecules in solid hcp para-hydrogen (p-H2) and ortho-deuterium (o-D2) has been investigated by using the path integral centroid molecular dynamics (CMD) simulations at zero-pressure and 5.4 and 5.0 K, respectively. For this purpose, we have newly unified the standard CMD method with the Parrinello-Rahman-Nosé-Hoover-chain-type isothermal-isobaric technique. The phonon density of states have been obtained and the dynamic structure factors have been calculated to observe the phonon dispersion relations of both crystals. For solid p-H2, the high energy edge of the phonon energies of solid p-H2 is >13 meV, and the calculated phonon energies are significantly higher than those observed in Nielsen's previous neutron scattering experiments in the energy region >9 meV. The relationship between the present results and the data reported so far is discussed to resolve the outstanding controversy regarding the phonon energies in solid p-H2. On the other hand, the excitation energies for solid o-D2 are in fairly good agreement with those of the neutron experiments. The calculated isothermal compressibility of solid p-H2 is found to be very close to the experimental result.

  17. Dynamics and phase transitions in solid ortho and para hydrogen and deuterium from an ab initio potential

    NASA Astrophysics Data System (ADS)

    Janssen, W. B. J. M.; van der Avoird, A.

    1990-07-01

    Starting from an ab initio H2-H2 potential that contains anisotropic short-range and dispersion terms, in addition to the quadrupole-quadrupole interactions, we have performed lattice-dynamics calculations for the orientationally disordered hexagonal (hcp) and ordered cubic (Pa3) phases of solid (ortho and para) hydrogen and deuterium. The method used is the time-dependent Hartree (TDH) formalism, with the explicit inclusion of translation-rotation coupling. By an anharmonic expansion of the potential through sixth order in the molecular displacements and the use of wave functions for the translational vibrations that are sufficiently flexible to adapt to this strong anharmonicity, we could avoid the usual (effective) Jastrow correction to the potential. The calculated phonon and roton or libron frequencies are in fairly good agreement with infrared, Raman, and neutron-scattering data, significantly better in general than the results from earlier (separate) phonon calculations and roton or libron calculations that have used empirical potentials. The transition pressure for ordering para-H2 or ortho-D2 appears to be dominated by the classical quadrupole-quadrupole interactions. It is significantly affected by the increase of the rotational constant and, especially, by the reduction of the quadrupole moment, which follows from a shortening of the intramolecular bond. Translation-rotation coupling yields the observed mixing of phonons and rotons at high pressure, but its effect on the transition pressure is minute. The remaining discrepancy between the calculated and observed transition pressures must be caused by three-body interactions and by correlations between the molecular motions that are beyond the TDH approximation.

  18. Elastic wave from fast heavy ion irradiation on solids

    NASA Astrophysics Data System (ADS)

    Kambara, T.; Kageyama, K.; Kanai, Y.; Kojima, T. M.; Nanai, Y.; Yoneda, A.; Yamazaki, Y.

    2002-06-01

    To study the time-dependent mechanical effects of fast heavy ion irradiations, we have irradiated various solids by a short-bunch beam of 95 MeV/u Ar ions and observed elastic waves generated in the bulk. The irradiated targets were square-shaped plates of poly-crystals of metals (Al and Cu), invar alloy, ceramic (Al 2O 3), fused silica (SiO 2) and single crystals of KC1 and LiF with a thickness of 10 mm. The beam was incident perpendicular to the surface and all ions were stopped in the target. Two piezo-electric ultrasonic sensors were attached to the surface of the target and detected the elastic waves. The elastic waveforms as well as the time structure and intensity of the beam bunch were recorded for each shot of a beam bunch. The sensor placed opposite to the beam spot recorded a clear waveform of the longitudinal wave across the material, except for the invar and fused silica targets. From its propagation time along with the sound velocity and the thickness of the target, the depth of the wave source was estimated. The result was compared with ion ranges calculated for these materials by TRIM code.

  19. Shock compression of precompressed deuterium

    SciTech Connect

    Armstrong, M R; Crowhurst, J C; Zaug, J M; Bastea, S; Goncharov, A F; Militzer, B

    2011-07-31

    Here we report quasi-isentropic dynamic compression and thermodynamic characterization of solid, precompressed deuterium over an ultrafast time scale (< 100 ps) and a microscopic length scale (< 1 {micro}m). We further report a fast transition in shock wave compressed solid deuterium that is consistent with the ramp to shock transition, with a time scale of less than 10 ps. These results suggest that high-density dynamic compression of hydrogen may be possible on microscopic length scales.

  20. Irradiated interplanetary dust particles as a possible solution for the deuterium/hydrogen paradox of Earth's oceans

    NASA Technical Reports Server (NTRS)

    Pavlov, A. A.; Pavlov, A. K.; Kasting, J. F.

    1999-01-01

    Determining the source of Earth's oceans is a longstanding problem in planetary science. Possible sources of water include water ice or water of hydration of silicate minerals in the original material from which the bulk Earth accreted and water brought in by late-arriving planetesimals during the heavy bombardment period (4.5-3.8 Gyr ago) [Chyba, 1989, 1991]. Comets are an attractive source of water because their origin in the outer solar system is consistent with the long timescale for heavy bombardment. However, the high deuterium/hydrogen (D/H) ratio of the three comets that have been studied, Halley, Hyakutake, and Hale-Bopp, indicates that Earth must have had a source with a low-D/H ratio as well. Here we suggest that solar wind-implanted hydrogen on interplanetary dust particles (IDPs) provided the necessary low-D/H component of Earth's water inventory.

  1. Optimization of the neutron yield in fusion plasmas produced by Coulomb explosions of deuterium clusters irradiated by a petawatt laser.

    PubMed

    Bang, W; Dyer, G; Quevedo, H J; Bernstein, A C; Gaul, E; Donovan, M; Ditmire, T

    2013-02-01

    The kinetic energy of hot (multi-keV) ions from the laser-driven Coulomb explosion of deuterium clusters and the resulting fusion yield in plasmas formed from these exploding clusters has been investigated under a variety of conditions using the Texas Petawatt laser. An optimum laser intensity was found for producing neutrons in these cluster fusion plasmas with corresponding average ion energies of 14 keV. The substantial volume (1-10 mm(3)) of the laser-cluster interaction produced by the petawatt peak power laser pulse led to a fusion yield of 1.6×10(7) neutrons in a single shot with a 120 J, 170 fs laser pulse. Possible effects of prepulses are discussed.

  2. Decomposition of solid amorphous hydrogen peroxide by ion irradiation

    SciTech Connect

    Loeffler, Mark J.; Teolis, Ben D.; Baragiola, Raul A.

    2006-03-14

    We present laboratory studies of the radiolysis of pure (97%) solid H{sub 2}O{sub 2} films by 50 keV H{sup +} at 17 K. Using UV-visible and infrared reflectance spectroscopies, a quartz-crystal microbalance, and a mass spectrometer, we measured the absolute concentrations of the H{sub 2}O, O{sub 2}, H{sub 2}O{sub 2}, and O{sub 3} products as a function of irradiation fluence. Ozone was identified by both UV and infrared spectroscopies and O{sub 2} from its forbidden transition in the infrared at 1550 cm{sup -1}. From the measurements we derive radiation yields, which we find to be particularly high for the decomposition of hydrogen peroxide; this can be explained by the occurrence of a chemical chain reaction.

  3. Surface morphology changes and deuterium retention in Toughened, Fine-grained Recrystallized Tungsten under high-flux irradiation conditions

    NASA Astrophysics Data System (ADS)

    Oya, M.; Lee, H. T.; Ueda, Y.; Kurishita, H.; Oyaidzu, M.; Hayashi, T.; Yoshida, N.; Morgan, T. W.; De Temmerman, G.

    2015-08-01

    Surface morphology changes and deuterium (D) retention in Toughened, Fine-Grained Recrystallized Tungsten (TFGR W) with TaC dispersoids (W-TaC) and pure tungsten exposed to D plasmas to a fluence of 1026 D/m2 s were studied as a function of the D ion flux (1022-1024 D/m2 s). As the flux increased from 1022 D/m2 s to 1024 D/m2 s, the numbers of blisters increased for both materials. However, smaller blisters were observed on W-TaC compared to pure W. In W-TaC, cracks beneath the surface along grain boundaries were observed, which were comparable to the blister sizes. The reason for the smaller blister sizes may arise from smaller grain sizes of W-TaC. In addition, reduction of the D retention in W-TaC was observed for higher flux exposures. D depth profiles indicate this reduction arises due to decrease in trapping in the bulk.

  4. Thermal Effects Induced by Laser Irradiation of Solids

    SciTech Connect

    Galovic, S.

    2004-12-01

    A part of incident energy is absorbed within the irradiated sample when a solid is exposed to the influence of laser radiation, to more general electromagnetic radiation within the wide range of wavelengths (from microwaves, to infrared radiation to X-rays), or to the energy of particle beams (electronic, protonic, or ionic). The absorption process signifies a highly selective excitation of the electronic state of atoms or molecules, followed by thermal and non-thermal de-excitation processes. Non-radiation de-excitation-relaxation processes induce direct sample heating. In addition, a great number of non-thermal processes (e.g., photoluminescence, photochemistry, photovoltage) may also induce heat generation as a secondary process. This method of producing heat is called the photothermal effect.The photothermal effect and subsequent propagation of thermal waves on the surface and in the volume of the solid absorbing the exciting beam may produce the following: variations in the temperature on the surfaces of the sample; deformation and displacement of surfaces; secondary infrared radiation (photothermal radiation); the formation of the gradient of the refractivity index; changes in coefficients of reflection and absorbtion; the generation of sound (photoacoustic generation), etc. These phenomena may be used in the investigation and measurement of various material properties since the profile and magnitude of the generated signal depend upon the nature of material absorbing radiation. A series of non-destructive spectroscopic, microscopic and defectoscopic detecting techniques, called photothermal methods, is developed on the basis of the above-mentioned phenomena.This paper outlines the interaction between the intensity modulated laser beam and solids, and presents a mathematical model of generated thermal sources. Generalized models for a photothermal response of optically excited materials have been obtained, including thermal memory influence on the propagation

  5. Use of deuterium labeling by high-temperature solid-state hydrogen-exchange reaction for mass spectrometric analysis of bradykinin biotransformation.

    PubMed

    Kopylov, Arthur T; Myasoedov, Nikolay F; Dadayan, Alexander K; Zgoda, Victor G; Medvedev, Alexei E; Zolotarev, Yurii A

    2016-06-15

    Studies of molecular biodegradation by mass spectrometry often require synthetic compounds labeled with stable isotopes as internal standards. However, labeling is very expensive especially when a large number of compounds are needed for analysis of biotransformation. Here we describe an approach for qualitative and quantitative analysis using bradykinin (BK) and its in vitro degradation metabolites as an example. Its novelty lies in the use of deuterated peptides which are obtained by a high-temperature solid-state exchange (HSCIE) reaction. Deuterated and native BK were analyzed by positive electrospray ionization high-resolution mass spectrometry (ESI-HRMS) using an Orbitrap Fusion mass spectrometer. High-energy collision-induced dissociation (HCD) experiments were performed on [M+H](+) and [M+2H](2+) ions in targeted-MS(2) mode with adjusted normalized HCD value. After the HSCIE reaction, each amino acid residue of the deuterated peptide contained deuterium atoms and the average degree of substitution was 5.5 atoms per the peptide molecule. The deuterated peptide demonstrated the same chromatographic mobility as the unlabeled counterpart, and lack of racemization during substitution with deuterium. Deuterium-labeled and unlabeled BKs were incubated with human plasma and their corresponding fragments BK(1-5) and BK(1-7), well known as the major metabolites, were detected. Quantitative assays demonstrated applicability of the heavy peptide for both sequencing and quantification of generated fragments. Applicability of the HSCIE deuterated peptide for analysis of routes of its degradation has been shown in in vitro experiments. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  6. Analysis of diffential absorption lidar technique for measurements of anhydrous hydrogen chloride from solid rocket motors using a deuterium fluoride laser

    NASA Technical Reports Server (NTRS)

    Bair, C. H.; Allario, F.

    1977-01-01

    An active optical technique (differential absorption lidar (DIAL)) for detecting, ranging, and quantifying the concentration of anhydrous HCl contained in the ground cloud emitted by solid rocket motors (SRM) is evaluated. Results are presented of an experiment in which absorption coefficients of HCl were measured for several deuterium fluoride (DF) laser transitions demonstrating for the first time that a close overlap exists between the 2-1 P(3) vibrational transition of the DF laser and the 1-0 P(6) absorption line of HCl, with an absorption coefficient of 5.64 (atm-cm) to the -1 power. These measurements show that the DF laser can be an appropriate radiation source for detecting HCl in a DIAL technique. Development of a mathematical computer model to predict the sensitivity of DIAL for detecting anhydrous HCl in the ground cloud is outlined, and results that assume a commercially available DF laser as the radiation source are presented.

  7. Sub-100 ps laser-driven dynamic compression of solid deuterium with a ∼40 μJ laser pulse

    SciTech Connect

    Armstrong, Michael R. Crowhurst, Jonathan C.; Bastea, Sorin; Zaug, Joseph M.; Goncharov, Alexander F.

    2014-07-14

    We dynamically compress solid deuterium over <100 ps from initial pressures of 22 GPa to 55 GPa, to final pressures as high as 71 GPa, with <40 μJ of pulse energy. At 25 GPa initial pressure, we measure compression wave speeds consistent with quasi-isentropic compression and a 24% increase in density. The laser drive energy per unit density change is 10{sup 9} times smaller than it is for recent longer (∼30 ns) time scale compression experiments. This suggests that, for a given final density, dynamic compression of hydrogen might be achieved using orders of magnitude lower laser energy than currently used.

  8. Deuterium separation by infrared-induced addition reaction

    DOEpatents

    Marling, John B.

    1977-01-01

    A method for deuterium enrichment by the infrared-induced addition reaction of a deuterium halide with an unsaturated aliphatic compound. A gaseous mixture of a hydrogen halide feedstock and an unsaturated aliphatic compound, particularly an olefin, is irradiated to selectively vibrationally excite the deuterium halide contained therein. The excited deuterium halide preferentially reacts with the unsaturated aliphatic compound to produce a deuterated addition product which is removed from the reaction mixture.

  9. The Effects of Temperature and Oxidation on Deuterium Retention in Solid and Liquid Lithium Films on Molybdenum Plasma-Facing Components

    NASA Astrophysics Data System (ADS)

    Capece, Angela

    2014-10-01

    Liquid metal plasma-facing components (PFCs) enable in-situ renewal of the surface, thereby offering a solution to neutron damage, erosion, and thermal fatigue experienced by solid PFCs. Lithium in particular has a high chemical affinity for hydrogen, which has resulted in reduced recycling and enhanced plasma performance on many fusion devices including TFTR, T11-M, FTU, CDX-U, LTX, TJ-II, and NSTX. A key component to the improvement in plasma performance is deuterium retention in Li; however, this process is not well understood in the complex tokamak environment. Recent surface science experiments conducted at the Princeton Plasma Physics Laboratory have used electron spectroscopy and temperature programmed desorption to understand the mechanisms for D retention in Li coatings on Mo substrates. The experiments were designed to give monolayer-control of Li films and were conducted in ultrahigh vacuum under controlled environments. An electron cyclotron resonance plasma source was used to deliver a beam of deuterium ions to the surface over a range of ion energies. Our work shows that D is retained as LiD in metallic Li films. However, when oxygen is present in the film, either by diffusion from the subsurface at high temperature or as a contaminant during the deposition process, Li oxides are formed that retain D as LiOD. Experiments indicate that LiD is more thermally stable than LiOD, which decomposes to liberate D2 gas and D2O at temperatures 100 K lower than the LiD decomposition temperature. Other experiments show how D retention varies with substrate temperature to provide insight into the differences between solid and liquid lithium films. This work was supported by DOE Contract No. DE AC02-09CH11466.

  10. New on-line methods for determining the deuterium/hydrogen composition of water and hydrocarbon gases using O(2-) ion-conducting solid electrolyte reactor.

    PubMed

    Sevastyanov, Vyacheslav S; Pedentchouk, Nikolai; Babulevich, Nataliya E; Galimov, Eric M

    2012-11-30

    The deuterium/hydrogen (D/H) composition of water and hydrocarbon gases is widely used in geological, environmental and petroleum studies. The aim of this work was to develop a simple reduction zirconium dioxide solid electrolyte reactor (SER) for water decomposition and new methods for measuring hydrogen isotope ratios in water and hydrocarbon gases. δ(2)H(VSMOW) values were determined using two new different on-line methods: solid electrolyte reactor isotope ratio mass spectrometry (SER-IRMS) for water and gas chromatography combustion solid electrolyte reactor isotope ratio mass spectrometry (GC-C-SER-IRMS) for hydrocarbon gases. We have designed a solid electrolyte reactor based on oxygen ion-conducting zirconium dioxide stabilized by yttria (Y(2)O(3)). The reactor was used for catalytic electrochemical decomposition of water in a helium carrier gas. The solid electrolyte reactor has a small internal volume of 0.1 cm(3). It was operated at a temperature of ~950 °C. The total time of analysis for determining the hydrogen isotope ratio in water was 150 s. A typical water sample volume was about 0.2 μL (split ratio 500:1). The precision of the δ(2) H(VSMOW) measurements for water was better than or equal to 2.2‰ and that for hydrocarbon gases was within 0.5-3.0‰. Fast, simple and accurate on-line methods (SER-IRMS and GC-C-SER-IRMS) were developed. The SER-IRMS method makes it possible to work with small water samples. Although the GC-C-SER-IRMS method was developed for hydrocarbons, it can also be used for other organic gases and their mixtures. The new solid electrolyte reactor for water decomposition is low cost and the ceramic tube is inexpensive. Copyright © 2012 John Wiley & Sons, Ltd.

  11. Results from the irradiation of stainless steel and copper by 23 MeV γ-quanta in the atmosphere of molecular deuterium at a pressure of 2 kbar

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wisniewski, R.

    2014-05-01

    Metal samples were arranged inside a "finger-type" high-pressure chamber (DHPC-FT) filled by deuterium. They were two aluminum rods, a copper rod, two specimens of homogeneous YMn2 alloy, and a stainless steel wire. The pressure of molecular deuterium in DHPC-FT was about 2 kbar. The samples were irradiated by braking γ-quanta at a threshold energy of 23 MeV. All the samples were studied using scanning electron microscopy (SEM) and X-ray (roentgen) microelement probe analysis (RMPA). Considerable changes in the surface structure and elemental composition were found for the samples of copper, aluminum, YMn2 alloy, and stainless steel. Unusual results were analyzed in detail and compared with the earlier data.

  12. Effect of gamma irradiation on cefotaxime in the solid state

    NASA Astrophysics Data System (ADS)

    Żegota, Henryk; Koprowski, Marek; Zegota, Alicja

    1995-02-01

    The effect of γ-irradiation on cefotaxime, a member of the third generation of cephalosporins, has been investigated by using different spectroscopic, chromatographic and microbiological analytical methods. Cefotaxime sodium salt was irradiated in dry state in the range of sterilization doses from 5.85 to 46.8 kGy. According to the results obtained, the degree of cefotaxime alteration was lower than 1%, even for the higher radiation dose used. Trace amounts of antibiotic radiolysis products have been found by HPLC. The microbiological assay carried out using E. coli test strain reveal that the activity of irradiated cefotaxime did not decrease.

  13. Protein Internal Dynamics Associated With Pre-System Glass Transition Temperature Endothermic Events: Investigation of Insulin and Human Growth Hormone by Solid State Hydrogen/Deuterium Exchange.

    PubMed

    Fang, Rui; Grobelny, Pawel J; Bogner, Robin H; Pikal, Michael J

    2016-11-01

    Lyophilized proteins are generally stored below their glass transition temperature (Tg) to maintain long-term stability. Some proteins in the (pure) solid state showed a distinct endotherm at a temperature well below the glass transition, designated as a pre-Tg endotherm. The pre-Tg endothermic event has been linked with a transition in protein internal mobility. The aim of this study was to investigate the internal dynamics of 2 proteins, insulin and human growth hormone (hGH), both of which exhibit the pre-Tg endothermic event with onsets at 50°C-60°C. Solid state hydrogen/deuterium (H/D) exchange of both proteins was characterized by Fourier transform infrared spectroscopy over a temperature range from 30°C to 80°C. A distinct sigmoidal transition in the extent of H/D exchange had a midpoint of 56.1 ± 1.2°C for insulin and 61.7 ± 0.9°C for hGH, suggesting a transition to greater mobility in the protein molecules at these temperatures. The data support the hypothesis that the pre-Tg event is related to a transition in internal protein mobility associated with the protein dynamical temperature. Exceeding the protein dynamical temperature is expected to activate protein internal motion and therefore may have stability consequences.

  14. Changes of surface structure and elemental composition of Pd rod and collector of nuclear reaction products irradiated with 10-MeV γ-quanta in dense deuterium gas

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wiśniewski, R.; Wilczynska-Kitowska, T.

    2013-12-01

    A high-pressure chamber is filled with 1.2 kbar molecular deuterium (DHPC). The palladium rod saturated with deuterium is loaded inside the DHPC and irradiated with 10-MeV bremsstrahlung γ-quanta for 18 h with a 11-13 μA electron beam using the MT-25 electron accelerator. The elemental compositions of all surfaces of the DHPC element inside the dense deuterium gas were studied using scanning electronic microscopes with X-ray microelement microprobe analysis. It is found that all surfaces, including the surface of a high-purity palladium rod (99.995%), are covered with a partly homogeneous layer or large microparticles of lead. Also, light elements such as 6C, 8O, 11Na, 12Mg, 13Al, 14Si, 22Ti, 25Mn, 26Fe, 29Cu, and 30Zn and heavy metals such as 47Ag, 73Ta, 74W, 78Pt, 79Au, and 82Pb are observed. Possible processes that can cause the anomalies observed in the newly formed chemical elements are briefly discussed.

  15. Elastic deformation and area per lipid of membranes: atomistic view from solid-state deuterium NMR spectroscopy.

    PubMed

    Kinnun, Jacob J; Mallikarjunaiah, K J; Petrache, Horia I; Brown, Michael F

    2015-01-01

    This article reviews the application of solid-state ²H nuclear magnetic resonance (NMR) spectroscopy for investigating the deformation of lipid bilayers at the atomistic level. For liquid-crystalline membranes, the average structure is manifested by the segmental order parameters (SCD) of the lipids. Solid-state ²H NMR yields observables directly related to the stress field of the lipid bilayer. The extent to which lipid bilayers are deformed by osmotic pressure is integral to how lipid-protein interactions affect membrane functions. Calculations of the average area per lipid and related structural properties are pertinent to bilayer remodeling and molecular dynamics (MD) simulations of membranes. To establish structural quantities, such as area per lipid and volumetric bilayer thickness, a mean-torque analysis of ²H NMR order parameters is applied. Osmotic stress is introduced by adding polymer solutions or by gravimetric dehydration, which are thermodynamically equivalent. Solid-state NMR studies of lipids under osmotic stress probe membrane interactions involving collective bilayer undulations, order-director fluctuations, and lipid molecular protrusions. Removal of water yields a reduction of the mean area per lipid, with a corresponding increase in volumetric bilayer thickness, by up to 20% in the liquid-crystalline state. Hydrophobic mismatch can shift protein states involving mechanosensation, transport, and molecular recognition by G-protein-coupled receptors. Measurements of the order parameters versus osmotic pressure yield the elastic area compressibility modulus and the corresponding bilayer thickness at an atomistic level. Solid-state ²H NMR thus reveals how membrane deformation can affect protein conformational changes within the stress field of the lipid bilayer.

  16. Observation of a two-vibron bound-to-unbound transition in solid deuterium at high pressure

    NASA Technical Reports Server (NTRS)

    Eggert, Jon H.; Mao, Ho-Kwang; Hemley, Russell J.

    1993-01-01

    We have observed a two-vibron bound-to-unbound transition in solid D2 by Raman scattering at a pressure of 34(2) GPa. We investigated the transition by increasing the vibron bandwidth, through the application of pressure, until it dominated the intramolecular anharmonicity. We present an analysis of a simple Hamiltonian that gives the experimental bivibron binding energy and the critical bandwidth-to-anharmonicity ratio. Our results indicate that while the vibron bandwidth increases markedly with pressure, the anharmonicity remains constant.

  17. Measured Total Cross Sections of Slow Neutrons Scattered by Solid Deuterium and Implications for Ultracold Neutron Sources

    SciTech Connect

    Atchison, F.; Blau, B.; Brandt, B. van den; Brys, T.; Daum, M.; Fierlinger, P.; Hautle, P.; Henneck, R.; Heule, S.; Kirch, K.; Kohlbrecher, J.; Kuehne, G.; Konter, J.A.; Pichlmaier, A.; Wokaun, A.; Bodek, K.; Kasprzak, M.; Kuzniak, M.; Geltenbort, P.; Zmeskal, J.

    2005-10-28

    The total scattering cross sections for slow neutrons with energies in the range 100 neV to 3 meV for solid ortho-{sup 2}H{sub 2} at 18 and 5 K, frozen from the liquid, have been measured. The 18 K cross sections are found to be in excellent agreement with theoretical expectations and for ultracold neutrons dominated by thermal up scattering. At 5 K the total scattering cross sections are found to be dominated by the crystal defects originating in temperature induced stress but not deteriorated by temperature cycles between 5 and 10 K.

  18. Damage accumulation in ion-irradiated Ni-based concentrated solid-solution alloys

    DOE PAGES

    Ullah, Mohammad W.; Aidhy, Dilpuneet S.; Zhang, Yanwen; ...

    2016-03-05

    We investigate Irradiation-induced damage accumulation in Ni0.8Fe0.2 and Ni0.8Cr0.2 alloys by using molecular dynamics simulations to assess possible enhanced radiation-resistance in these face-centered cubic (fcc), single-phase, concentrated solid-solution alloys, as compared with pure fcc Ni.

  19. Determination of the tautomeric equilibria of pyridoyl benzoyl β-diketones in the liquid and solid state through the use of deuterium isotope effects on (1)H and (13)C NMR chemical shifts and spin coupling constants.

    PubMed

    Hansen, Poul Erik; Borisov, Eugeny V; Lindon, John C

    2015-02-05

    The tautomeric equilibria for 2-pyridoyl-, 3-pyridoyl-, and 4-pyridoyl-benzoyl methane have been investigated using deuterium isotope effects on (1)H and (13)C chemical shifts both in the liquid and the solid state. Equilibria are established both in the liquid and the solid state. In addition, in the solution state the 2-bond and 3-bond J((1)H-(13)C) coupling constants have been used to confirm the equilibrium positions. The isotope effects due to deuteriation at the OH position are shown to be superior to chemical shift in determination of equilibrium positions of these almost symmetrical -pyridoyl-benzoyl methanes. The assignments of the NMR spectra are supported by calculations of the chemical shifts at the DFT level. The equilibrium positions are shown to be different in the liquid and the solid state. In the liquid state the 4-pyridoyl derivative is at the B-form (C-1 is OH), whereas the 2-and 3-pyridoyl derivatives are in the A-form. In the solid state all three compounds are on the B-form. The 4-pyridoyl derivative shows unusual deuterium isotope effects in the solid, which are ascribed to a change of the crystal structure of the deuteriated compound. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Hydration water dynamics in bovine serum albumin at low temperatures as studied by deuterium solid-state NMR

    NASA Astrophysics Data System (ADS)

    Miyatou, Tatsuya; Araya, Takashi; Ohashi, Ryutaro; Ida, Tomonori; Mizuno, Motohiro

    2016-10-01

    Solid state 2H NMR was used to investigate changes in the structure and dynamics of hydration waters of bovine serum albumin (BSA) due to glass transitions. The 2H NMR spectra were separated into fast and slow components based on differences in spin-lattice relaxation time T1. The fast components corresponded to water molecules interacting with protein while the slow components were the water molecules similar to bulk water and deuterons of the protein backbone. Simulation analysis of the 2H NMR spectra of the fast components was used to assess the mode and rate of motions of hydration waters around the protein. At low temperatures, the water molecules underwent a 180° flip and slow reorientation in the tetrahedral sites. The distribution of the rate of the 180° flip and the D-O-D angle of water molecules were clarified. The distribution of the D-O-D angle of water molecules spread with decreasing temperature. The marked slowing down in the reorientation of water molecules was observed at a glass transition of around 200 K, which is linked to the disordered region of the protein. In contrast, the 180° flip of water molecules occurred frequently, even below 200 K. A freeze of the 180° flip of water molecules was observed around the glass transition temperature of 110 K, where primary hydrate water formed a direct hydrogen bond with the protein, making it perfectly immobile.

  1. Cometary deuterium.

    PubMed

    Meier, R; Owen, T C

    1999-01-01

    Deuterium fractionations in cometary ices provide important clues to the origin and evolution of comets. Mass spectrometers aboard spaceprobe Giotto revealed the first accurate D/H ratios in the water of Comet 1P/Halley. Ground-based observations of HDO in Comets C/1996 B2 (Hyakutake) and C/1995 O1 (Hale-Bopp), the detection of DCN in Comet Hale-Bopp, and upper limits for several other D-bearing molecules complement our limited sample of D/H measurements. On the basis of this data set all Oort cloud comets seem to exhibit a similar (D/H)H2O ratio in H2O, enriched by about a factor of two relative to terrestrial water and approximately one order of magnitude relative to the protosolar value. Oort cloud comets, and by inference also classical short-period comets derived from the Kuiper Belt cannot be the only source for the Earth's oceans. The cometary O/C ratio and dynamical reasons make it difficult to defend an early influx of icy planetesimals from the Jupiter zone to the early Earth. D/H measurements of OH groups in phyllosilicate rich meteorites suggest a mixture of cometary water and water adsorbed from the nebula by the rocky grains that formed the bulk of the Earth may be responsible for the terrestrial D/H. The D/H ratio in cometary HCN is 7 times higher than the value in cometary H2O. Species-dependent D-fractionations occur at low temperatures and low gas densities via ion-molecule or grain-surface reactions and cannot be explained by a pure solar nebula chemistry. It is plausible that cometary volatiles preserved the interstellar D fractionation. The observed D abundances set a lower limit to the formation temperature of (30 +/- 10) K. Similar numbers can he derived from the ortho-to-para ratio in cometary water, from the absence of neon in cometary ices and the presence of S2. Noble gases on Earth and Mars, and the relative abundance of cometary hydrocarbons place the comet formation temperature near 50 K. So far all cometary D/H measurements refer to

  2. Is the pre-Tg DSC endotherm observed with solid state proteins associated with the protein internal dynamics? Investigation of bovine serum albumin by solid state hydrogen/deuterium exchange.

    PubMed

    Mizuno, Masayasu; Pikal, Michael J

    2013-10-01

    DSC thermograms of solid state pure proteins often show a distinct endotherm at a temperature far below the glass transition temperature of the system (Tg). We hypothesized this endotherm represents enthalpy recovery associated with an internal mobility transition of the protein molecule. Although the existence of an internal transition has been postulated, whether this endotherm is associated with such a transition has not previously been discussed. The purpose of this study was to investigate the origin of the pre-Tg endotherm in lyophilized bovine serum albumin (BSA). Due to strong glass behavior, the system Tg was determined by extrapolating Tg data of disaccharide/BSA formulations to zero saccharide. A small pre-Tg endotherm around 40-60 °C was observed in amorphous BSA equilibrated at 11%RH. The apparent activation energy suggested the endotherm was "α-mobility"-related. A solid state hydrogen/deuterium exchange study using FTIR was conducted over a temperature range spanning the endotherm. We found a fast phase, followed by essentially a plateau level which is highly temperature dependent in the 40-60 °C range, suggesting enhanced internal protein motion as the system passes through the temperature range of the endotherm. These results suggest the pre-Tg endotherm is associated with a protein internal mobility transition.

  3. CT of irradiated solid tumor metastases to the brain.

    PubMed

    Brown, S B; Brant-Zawadzki, M; Eifel, P; Coleman, C N; Enzmann, D R

    1982-01-01

    Twenty patients with solid tumor metastases to the brain, demonstrated by CT scanning, had follow-up scans after radiation therapy of the metastatic focus. Nine patients (45%) showed no evidence of the metastasis on the initial follow-up scans. Another 10 patients (50%) showed some improvement in the size, enhancement, or surrounding edema of the lesion. Only one patient showed progression in spite of therapy. The CT scan identified those patients who achieved longer survival and/or longer time intervals before brain relapse. However, CT scans must be interpreted with caution in patients still on corticosteroid treatment. Additionally, other non-tumoral conditions may mimic tumor recurrence. Radiation therapy offered palliation in patients with brain metastases, and in some instances, sterilized patients of their metastatic brain involvement.

  4. Determination of dosimetric and kinetic features of gamma irradiated solid calcium ascorbate dihydrate using ESR spectroscopy

    NASA Astrophysics Data System (ADS)

    Tuner, H.

    2013-01-01

    Effects of gamma radiation on solid calcium ascorbate dihydrate were studied using electron spin resonance (ESR) spectroscopy. Irradiated samples were found to present two specific ESR lines with shoulder at low and high magnetic field sides. Structural and kinetic features of the radicalic species responsible for experimental ESR spectrum were explored through the variations of the signal intensities with applied microwave power, variable temperature, high-temperature annealing and room temperature storage time studies. Dosimetric potential of the sample was also determined using spectrum area and measured signal intensity measurements. It was concluded that three radicals with different spectroscopic and kinetic features were produced upon gamma irradiation.

  5. Infrared presensitization photography at deuterium fluoride laser wavelengths

    SciTech Connect

    Geary, J.M.; Ross, K.; Suter, K. )

    1989-09-01

    Near-field irradiance distributions of a deuterium flouride laser system are obtained using infrared presensitization photography. This represents the shortest wavelength region to employ this technique thus far.

  6. Calculation of deuterium retention, re-emission and reflection from a tungsten material under D + ions irradiation with ACAT-DIFFUSE code

    NASA Astrophysics Data System (ADS)

    Ono, T.; Kenmotsu, T.; Muramoto, T.; Kawamura, T.

    2009-06-01

    We calculated, with a dynamic Monte Carlo code ACAT-DIFFUSE, fluxes of thermal D 2 re-emission, reflection and segregated self-sputtering of D from a D + implanted wrought tungsten material during a time sequence of l00 eV D + implantation, post-implanted isothermal out-gassing and thermal desorption spectroscopy. The obtained result was in good agreement with an existing experiment if two different trap sites with de-trapping energy of 0.85 eV and 2.2 eV and density fraction of 0.05 D/W and 0.01 D/W were assumed to exist. The re-emission, reflection and self-sputtering fluxes in the implantation period were shown to be almost comparable. The integrated deuterium flux released in the same period was estimated. The amount of deuterium retained at 300 K was nearly six times higher than that at 473 K, which reflects the result that mobile atoms and atoms trapped in 0.85 eV trap existed abundantly at 300 K but scarcely at 473 K.

  7. Pyrolysis of Municipal Solid Waste for Syngas Production by Microwave Irradiation

    SciTech Connect

    Gedam, Vidyadhar V.; Regupathi, Iyyaswami

    2012-03-15

    In the present study, we discuss the application of microwave-irradiated pyrolysis of municipal solid waste (MSW) for total recovery of useful gases and energy. The MSW pyrolysis under microwave irradiation highly depends on the process parameters, like microwave power, microwave absorbers, and time of irradiation. The thoroughness of pyrolysis and product recovery were studied by changing the abovesaid variables. Pyrolysis of MSW occurs in the power rating range of 450-850 W-outside this power rating range, pyrolysis is not possible. Experiments were carried out using various microwave absorbers (i.e., graphite, charcoal, and iron) to enhance the pyrolysis even at lower power rating. The results show that the pyrolysis of MSW was possible even at low power ratings. The major composition of the pyrolysis gaseous product were analyzed with GC-MS which includes CO{sub 2}, CO, CH{sub 4}, etc.

  8. Infrared Spectra of Acetylene Diluted in Solid Nitrogen upon Irradiation with Vacuum Ultraviolet Light and Electrons

    NASA Astrophysics Data System (ADS)

    Wu, Yu-Jong; Chuang, Shiang-Jiun; Chen, Sian-Cong; Huang, Tzu-Ping

    2014-05-01

    Infrared spectra and chemical reactions of acetylene diluted in solid nitrogen at 10 K upon irradiation with vacuum ultraviolet (VUV) light and energetic electrons were investigated in separate experiments. Irradiation of the matrix sample with VUV light peaking at 160 and 121.6 nm yielded simple products, including C2H, CN, and isomers of C2N2. In contrast, electron irradiation of a similar sample generated N3, C2H, and various nitriles. The reaction mechanisms for photolysis and radiolysis of the matrix samples are discussed. Our results may help explain the distribution of trace species detected in the atmosphere of Titan. In addition, the UV absorption spectrum of the electron-bombarded icy sample was obtained and might be useful for future spectral investigations of Pluto by New Horizons.

  9. THEORY OF A QUODON GAS WITH APPLICATION TO PRECIPITATION KINETICS IN SOLIDS UNDER IRRADIATION

    SciTech Connect

    Dubinko, Volodymyr; Shapovalov, Roman V.

    2014-06-17

    Rate theory of the radiation-induced precipitation in solids is modified with account of non-equilibrium fluctuations driven by the “gas” of lattice solitons (a.k.a. “quodons”) produced by irradiation. According to quantitative estimations, a steady-state density of the quodon gas under sufficiently intense irradiation can be comparable to the density of classical phonon gas. The modified rate theory is applied to modelling of copper precipitation in FeCu binary alloys under electron irradiation. In contrast to the classical rate theory, which disagrees strongly with experimental data on all precipitation parameters, the modified rate theory describes quite well both the evolution of precipitates and the matrix concentration of copper measured by different methods.

  10. Chemical forms of solid fission products in the irradiated uranium—plutonium mixed nitride fuel

    NASA Astrophysics Data System (ADS)

    Arai, Yasuo; Maeda, Atsushi; Shiozawa, Ken-ichi; Ohmichi, Toshihiko

    1994-06-01

    Chemical forms of solid fission products in the irradiated (U, Pu)N fuel were estimated by both thermodynamic equilibrium calculation and electron microprobe analysis on burnup simulated samples prepared by carbothermic reduction. Besides the MX type matrix phase dissolving zirconium, niobium, yttrium and rare earth elements, the existence of two kinds of inclusion was recognized. One is URu 3 type intermetallic compound constituted by uranium and platinum group elements. The other is an alloy containing molybdenum as a principal constituent. Furthermore, the swelling rate due to solid fission products precipitation was evaluated to be about 0.5% per %FIMA.

  11. Probing Dense Plasmas Created from Intense Irradiation of Solid Target in the XUV Domain

    SciTech Connect

    Dobosz, S.; Doumy, G.; Stabile, H.; Monot, P.; Bougeard, M.; Reau, F.; Martin, Ph.

    2006-04-07

    In this paper, electronic density and temperature have been inferred from XUV transmission through hot solid-density plasma created by high temporal contrast femtosecond irradiation of thin plastic foil target in the 1018W/cm2 intensity range. High order harmonics generated in pulsed gas jet are used as a probe beam. The initial plasma parameters are determined with an accuracy better than 15% on the 100fs time scale, by comparison of the transmission of two consecutive harmonics.

  12. Damage accumulation in ion-irradiated Ni-based concentrated solid-solution alloys

    SciTech Connect

    Ullah, Mohammad W.; Aidhy, Dilpuneet S.; Zhang, Yanwen; Weber, William J.

    2016-01-01

    We investigate Irradiation-induced damage accumulation in Ni0.8Fe0.2 and Ni0.8Cr0.2 alloys by using molecular dynamics simulations to assess possible enhanced radiation-resistance in these face-centered cubic (fcc), single-phase, concentrated solid-solution alloys, as compared with pure fcc Ni.

  13. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    NASA Technical Reports Server (NTRS)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 10(exp 13) to 10(exp 15) n per square centimeters. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 10(exp 15) to 10(exp 16) n per square centimeters with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  14. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    NASA Astrophysics Data System (ADS)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 1013 to 1015 n/cm2. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 1015 to 1016 n/cm2 with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  15. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    SciTech Connect

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-30

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 1013 to 1015 n/cm2. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 1015 to 1016 n/cm2 with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  16. FTIR assessment of poly(ethylene oxide) irradiated in solid state, melt and aqeuous solution

    NASA Astrophysics Data System (ADS)

    Pucić, Irina; Jurkin, Tanja

    2012-09-01

    FTIR spectroscopy was used to study poly(ethylene oxide), PEO, irradiated in solid and molten aggregate states and as aqueous solutions of various concentrations. The changes in shape and width of -C-O-C- complex absorption intensities at around 1112 cm-1 were the most prominent. On irradiation of solid samples in contact with air shrinking of -C-O-C- complex and increase in its absorption intensities indicated predominant degradation. Crosslinking prevailed on irradiation of molten PEO and of its aqueous solutions in nitrogen atmosphere and manifested itself as widening of -C-O-C- absorption and decrease of corresponding intensities. Partial or complete merging of CH2 wagging vibrations at 1342 cm-1 and 1360 cm-1 that are characteristic of crystalline PEO into a single absorption at around 1350 cm-1 indicated amorphization what was observed for samples that had reduced degree of crystallinity determined by differential scanning calorimetry. DSC could not discriminate between degradation and crosslinking while the changes in width and shape of -C-O-C- complex were independent of the changes in crystallinity. Comparison of FTIR spectra of the same PEO samples obtained as thin film and as KBr pellets revealed that pellet preparation results in a number of spectral artefacts.

  17. Higher Efficiency for Quasi-Solid State Dye Sensitized Solar Cells Under Low Light Irradiance

    NASA Astrophysics Data System (ADS)

    Desilva, Ajith; Bandara, T. M. W. J.; Fernado, H. D. N. S.; Fernando, P. S. L.; Dissanayake, M. A. K. L.; Jayasundara, W. J. M. J. S. R.; Furlani, M.; Mellander, B.-E.

    2014-03-01

    Dye-sensitized solar cells (DSSCs), lower cost solar energy conversion devices are alternative green energy source. The liquid based electrolyte DSSCs have higher efficiencies with many practical issues while the quasi-solid-state DSSCs resolve the key problems but efficiencies are relatively low. Polyacrylonitrile (PAN) based gel polymer electrolytes were fabricated as DSSCs by incorporating ethylene carbonate and propylene carbonate plasticizers and tetrapropylammonium iodide salt. A thin layer of electrolyte was sandwiched between the TiO2 anode (sensitized with N719 dye) and the Pt counter electrode. The electrolyte had an ionic conductivity of 2.6 mS/cm at 25 degrees of Celsius. DSSCs incorporating this gel electrolyte revealed Vsc circuit, Jsc, fill factor (FF) and efficiency values of 0.71 V, 11.8 mA, 51 percent and 4.2 percent respectively under 1 sun irradiation. The efficiency of the cell increased with decreasing solar irradiance achieving up to 10 percent efficiency and 80 percent FF at low irradiance values. This work uncovers that quasi-solid state DSSCs can reach efficiencies close to that of liquid electrolytes based cells.

  18. Enhanced mass transfer during solid liquid extraction of gamma-irradiated red beetroot

    NASA Astrophysics Data System (ADS)

    Nayak, Chetan A.; Chethana, S.; Rastogi, N. K.; Raghavarao, K. S. M. S.

    2006-01-01

    The exposure to gamma-irradiation pretreatment increases cell wall permeabilization, resulting in loss of turgor pressure, which led to the increase of extractability of betanin from red beetroot. The degree of extraction of betanin was investigated using gamma irradiation as a pretreatment prior to the solid-liquid extraction process and compared with control beetroot samples. The beetroot subjected to different doses of gamma irradiation (2.5, 5.0, 7.5, 10.0 kGy) and control was dipped in an acetic acid medium (1% v/v) to extract the betanin. The diffusion coefficients for betanin as well as ionic component were estimated considering Fickian diffusion. The results indicated an increase in the diffusion coefficient of betanin (0.302×10 -9-0.463×10 -9 m 2/s) and ionic component (0.248×10 -9-0.453×10 -9 m 2/s) as the dose rate increased (from 2.5 to 10.0 kGy). The degradation constant was found to increase (0.050-0.079 min -1) with an increase gamma-irradiation doses (2.5-10.0 kGy), indicating lower stability of the betanin as compared to control sample at 65 °C.

  19. Computer experiments concerning palladium-deuterium and titanium-deuterium lattices - implications to phenomenon of low-energy nuclear reaction

    SciTech Connect

    Rao, K.R.; Chaplot, S.L.

    1996-12-01

    Short-lived large energy fluctuations (SLEFs) in solids, proposed by Khait, are known to be responsible for several anomalous properties in a variety of materials. The study of SLEFs in palladium-deuterium and titanium-deuterium lattices via computer experiments is reported. The relevance of these large energy fluctuations in penetrating coulombic barriers in these systems is discussed. Such dynamical effects arising from the phonon bath in solids may enhance nuclear reaction probabilities leading to cold fusion. Expected cold fusion reaction rates are reported taking into account the effective charges of the deuterium atoms in the solid and SLEF frequencies. 25 refs., 7 figs., 1 tab.

  20. Ion beam irradiation as a tool to improve the ionic conductivity in solid polymer electrolyte systems

    SciTech Connect

    Manjunatha, H. Kumaraswamy, G. N.; Damle, R.

    2016-05-06

    Solid polymer electrolytes (SPEs) have potential applications in solid state electronic and energy devices. The optimum conductivity of SPEs required for such applications is about 10{sup −1} – 10{sup −3} Scm{sup −1}, which is hard to achieve in these systems. It is observed that ionic conductivity of SPEs continuously increase with increasing concentration of inorganic salt in the host polymer. However, there is a critical concentration of the salt beyond which the conductivity of SPEs decreases due to the formation of ion pairs. In the present study, solid polymer thin films based on poly (ethylene oxide) (PEO) complexed with NaBr salt with different concentrations have been prepared and the concentration at which ion pair formation occurs in PEO{sub x}NaBr is identified. The microstructure of the SPE with highest ionic conductivity is modified by irradiating it with low energy O{sup +1} ion (100 keV) of different fluencies. It is observed that the ionic conductivity of irradiated SPEs increases by one order in magnitude. The increase in ionic conductivity may be attributed to the enhanced segmental motion of the polymer chains due to radiation induced micro structural modification.

  1. A novel solid state photocatalyst for living radical polymerization under UV irradiation.

    PubMed

    Fu, Qiang; McKenzie, Thomas G; Ren, Jing M; Tan, Shereen; Nam, Eunhyung; Qiao, Greg G

    2016-02-11

    This study presents the development of a novel solid state photocatalyst for the photoinduced controlled radical polymerization of methacrylates under mild UV irradiation (λmax ≈ 365 nm) in the absence of conventional photoinitiators, metal-catalysts or dye sensitizers. The photocatalyst design was based on our previous finding that organic amines can act in a synergistic photochemical reaction with thiocarbonylthio compounds to afford well controlled polymethacrylates under UV irradiation. Therefore, in the current contribution an amine-rich polymer was covalently grafted onto a solid substrate, thus creating a heterogeneous catalyst that would allow for facile removal, recovery and recyclability when employed for such photopolymerization reactions. Importantly, the polymethacrylates synthesized using the solid state photocatalyst (ssPC) show similarly excellent chemical and structural integrity as those catalysed by free amines. Moreover, the ssPC could be readily recovered and re-used, with multiple cycles of polymerization showing minimal effect on the integrity of the catalyst. Finally, the ssPC was employed in various photo-"click" reactions, permitting high yielding conjugations under photochemical control.

  2. A novel solid state photocatalyst for living radical polymerization under UV irradiation

    PubMed Central

    Fu, Qiang; McKenzie, Thomas G.; Ren, Jing M.; Tan, Shereen; Nam, Eunhyung; Qiao, Greg G.

    2016-01-01

    This study presents the development of a novel solid state photocatalyst for the photoinduced controlled radical polymerization of methacrylates under mild UV irradiation (λmax ≈ 365 nm) in the absence of conventional photoinitiators, metal-catalysts or dye sensitizers. The photocatalyst design was based on our previous finding that organic amines can act in a synergistic photochemical reaction with thiocarbonylthio compounds to afford well controlled polymethacrylates under UV irradiation. Therefore, in the current contribution an amine-rich polymer was covalently grafted onto a solid substrate, thus creating a heterogeneous catalyst that would allow for facile removal, recovery and recyclability when employed for such photopolymerization reactions. Importantly, the polymethacrylates synthesized using the solid state photocatalyst (ssPC) show similarly excellent chemical and structural integrity as those catalysed by free amines. Moreover, the ssPC could be readily recovered and re-used, with multiple cycles of polymerization showing minimal effect on the integrity of the catalyst. Finally, the ssPC was employed in various photo-“click” reactions, permitting high yielding conjugations under photochemical control. PMID:26863939

  3. Ion beam irradiation as a tool to improve the ionic conductivity in solid polymer electrolyte systems

    NASA Astrophysics Data System (ADS)

    Manjunatha, H.; Damle, R.; Kumaraswamy, G. N.

    2016-05-01

    Solid polymer electrolytes (SPEs) have potential applications in solid state electronic and energy devices. The optimum conductivity of SPEs required for such applications is about 10-1 - 10-3 Scm-1, which is hard to achieve in these systems. It is observed that ionic conductivity of SPEs continuously increase with increasing concentration of inorganic salt in the host polymer. However, there is a critical concentration of the salt beyond which the conductivity of SPEs decreases due to the formation of ion pairs. In the present study, solid polymer thin films based on poly (ethylene oxide) (PEO) complexed with NaBr salt with different concentrations have been prepared and the concentration at which ion pair formation occurs in PEOxNaBr is identified. The microstructure of the SPE with highest ionic conductivity is modified by irradiating it with low energy O+1 ion (100 keV) of different fluencies. It is observed that the ionic conductivity of irradiated SPEs increases by one order in magnitude. The increase in ionic conductivity may be attributed to the enhanced segmental motion of the polymer chains due to radiation induced micro structural modification.

  4. A novel solid state photocatalyst for living radical polymerization under UV irradiation

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; McKenzie, Thomas G.; Ren, Jing M.; Tan, Shereen; Nam, Eunhyung; Qiao, Greg G.

    2016-02-01

    This study presents the development of a novel solid state photocatalyst for the photoinduced controlled radical polymerization of methacrylates under mild UV irradiation (λmax ≈ 365 nm) in the absence of conventional photoinitiators, metal-catalysts or dye sensitizers. The photocatalyst design was based on our previous finding that organic amines can act in a synergistic photochemical reaction with thiocarbonylthio compounds to afford well controlled polymethacrylates under UV irradiation. Therefore, in the current contribution an amine-rich polymer was covalently grafted onto a solid substrate, thus creating a heterogeneous catalyst that would allow for facile removal, recovery and recyclability when employed for such photopolymerization reactions. Importantly, the polymethacrylates synthesized using the solid state photocatalyst (ssPC) show similarly excellent chemical and structural integrity as those catalysed by free amines. Moreover, the ssPC could be readily recovered and re-used, with multiple cycles of polymerization showing minimal effect on the integrity of the catalyst. Finally, the ssPC was employed in various photo-“click” reactions, permitting high yielding conjugations under photochemical control.

  5. Electron Irradiation Induced Phase Transition of an Amorphous Phase and Face-Centered Cubic Solid Solutions in Zr66.7Pd33.3 Metallic Glass

    NASA Astrophysics Data System (ADS)

    Nagase, Takeshi; Hosokawa, Takashi; Umakoshi, Yukichi

    2007-02-01

    Both amorphization and crystallization were observed in Zr66.7Pd33.3 metallic glass under electron irradiation. The melt-spun amorphous phase was not stable under 2.0 MV electron irradiation and two kinds of fcc-solid solution were precipitated through electron irradiation induced crystallization at 103 and 298 K. The fcc-solid solution obtained by electron irradiation induced crystallization at 298 K transformed to an amorphous phase during irradiation at 103 K. Electron irradiation induced phase transformation behavior in Zr66.7Pd33.3 metallic glass can be explained by phase stability of an amorphous phase and crystalline phases against electron irradiation.

  6. A solid target system with remote handling of irradiated targets for PET cyclotrons.

    PubMed

    Siikanen, J; Tran, T A; Olsson, T G; Strand, S-E; Sandell, A

    2014-12-01

    A solid target system was developed for a PET cyclotron. The system is compatible with many different target materials in the form of foils and electroplated/sputtered targets which makes it useful for production of a wide variety of different PET radionuclides. The target material is manually loaded into the system. Remote handling of irradiated target material is managed with a pneumatic piston and a vacuum technique which allows the targets to be dropped into a shielded transport container. To test the target performance, proton irradiations (12.8 MeV, 45 μA) of monoisotopic yttrium foils (0.64 mm, direct water cooling) were performed to produce 89Zr. The yields were 2200±200 MBq (1 h, n=13) and 6300±65 MBq (3 h, n=3).

  7. An efficient protocol for the solid-phase synthesis of glycopeptides under microwave irradiation.

    PubMed

    Garcia-Martin, Fayna; Hinou, Hiroshi; Matsushita, Takahiko; Hayakawa, Shun; Nishimura, Shin-Ichiro

    2012-02-28

    A standardized and smooth protocol for solid-phase glycopeptides synthesis under microwave irradiation was developed. Double activation system was proved to allow for highly efficient coupling of Tn-Ser/Thr and bulky core 2-Ser/Thr derivatives. Versatility and robustness of the present strategy was demonstrated by constructing a Mucine-1 (MUC1) fragment and glycosylated fragments of tau protein. The success of this approach relies on the combination of microwave energy, a resin consisting totally of polyethylene glycol, a low excess of sugar amino acid and the "double activation" method.

  8. Rapid solid-phase peptide synthesis using thermal and controlled microwave irradiation.

    PubMed

    Bacsa, Bernadett; Desai, Bimbisar; Dibó, Gábor; Kappe, C Oliver

    2006-10-01

    A rapid and efficient microwave-assisted solid-phase synthesis method is described for the preparation of the nonapeptide WDTVRISFK, using conventional Fmoc/Bu(t) orthogonal protection strategy. The synthesis protocol is based on the use of cycles of pulsed microwave irradiation with intermittent cooling of the reaction during the removal of the Fmoc protecting group and during the coupling. The desired nonapeptide was obtained in highest yield and purity by employing MicroKan technology. The chemical reactions were carried out in a single-mode microwave reactor, equipped with a fiber-optic probe to monitor the reaction temperature continuously.

  9. Cascade diffusion theory of sink capture fluctuations during irradiation of a solid

    SciTech Connect

    Mansur, L.K.; Brailsford, A.D.; Coghlan, W.A.

    1985-01-01

    Fluctuations in the number of defects captured by sinks in an irradiated solid, that arise because of the stochastic nature of collision cascade events, are analyzed. Two types of sinks are considered, cavities (or voids) and dislocations. The importance of the physical size of the sink is emphasized, as also is the magnitude of the fluctuations in defect capture relative to the behavior of its statistical mean. In particular, it is shown that the ratio of the variance to the mean, for either a cavity or a dislocation segment, decreases rapidly as overall steady state is approached. Further analytical and computational aspects of a shell model that we introduced earlier are analyzed. The relationship of this model to a truly random system is established, and additional calculations are presented to exemplify some of the features predicted by the mathematical analysis. Importance functions describing the spatial origins of the point defects contributing to the average concentration and flux are described. The probabilities of special types of cascade coincidences are developed. The application of the present formalism to the problems of void nucleation, and dislocation climb over localized obstacles, in irradiated solids is indicated.

  10. Low energy scatter due to in-situ irradiation of solid tumors in laboratory rats

    SciTech Connect

    Ritenour, E.R. Jr.

    1980-01-01

    A study of the pattern of scattered radiation in laboratory rat cadavers during irradiation of solid tumors on the animals' flanks was performed. The animals were wrapped in a lead shield having a circular cutout through which the tumor protruded. Irradiations were performed with a 250 kVp 15ma X-ray machine with a measured half value layer of 1.39 mmCu. Lead shielding was of sufficient thickness to attenuate essentially all of the beam. The absorbed dose measured in the animal was then due to internal scatter from the tumor. Arrays of thermoluminescent dosimeters (TLDs) were placed beneath the skin of 17 animals bearing a solid tumor (hepatoma H-4-II-E). Absorbed dose was seen to vary isotropically, decreasing as the inverse distance squared from the tumor. Analysis of experimental error played a major role in this study. A pilot study resulted in standard errors that were 35% of the mean absorbed dose measurements. A careful reassessment of methods of manipulating the animals and the dosimetry system resulted in a reduction in standard error to 14% of the mean for small groups (less than 10 animals).

  11. Incubation of solid state C60 fullerene under UV irradiation mimicking environmentally relevant conditions.

    PubMed

    Carboni, Andrea; Helmus, Rick; Parsons, John R; Kalbitz, Karsten; de Voogt, Pim

    2017-05-01

    Carbon-based nanomaterials, such as C60 fullerenes, are expected to accumulate in soil due to direct release and deposition from the atmosphere. However, little is known about the environmental fate of these nanoparticles which may be susceptible to photochemical and microbial degradation. In the present work, C60 was incubated for a period of 28 days and irradiated with UVA light. Three experiments were carried out where the fullerenes were either spiked onto a glass surface or added to quartz sand or sandy soil samples. At specific time intervals the samples were extracted and analysed by liquid chromatography coupled to UV or high resolution mass spectrometric (HRMS) detection. The fullerenes were degraded in all the treatments and the decay followed a pseudo-first-order rate law. In absence of a solid matrix, the half-life (t1⁄2) of the C60 was 13.1 days, with an overall degradation of 45.1% that was accompanied by the formation of functionalized C60-like structures. Furthermore, mass spectrometric analysis highlighted the presence of a large number of transformation products that were not directly related to the irradiation and presented opened cage and oxidized structures. When C60 was spiked into solid matrices the degradation occurred at a faster rate (t1⁄2 of 4.5 and 0.8 days for quartz sand and sandy soil, respectively). Minor but consistent losses were found in the non-irradiated samples, presumably due to biotic or chemical processes occurring in these samples. The results of this study suggest that light-mediated transformation of the fullerenes will occur in the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Phase Stability under Irradiation of Precipitates and Solid Solutions in Model ALloys and in ODS Alloys Relevant for Gen IV

    SciTech Connect

    Arthur T. Motta; Robert C. Birtcher

    2007-10-17

    The overall objective of this program is to investigate the irradiation-altered phase stability of oxide precipitates in ODS steels and of model alloy solid solutions of associated systems. This information can be used to determine whether the favorable mechanical propertiies of these steels are maintained under irradiation, thus addressing one of the main materials research issues for this class of steels as identified by the GenIV working groups. The research program will also create fundamental understanding of the irradiation precipitation/dissolution problem by studying a "model" system in which the variables can be controlled and their effects understood individually.

  13. Deuterium retention and desorption behavior in an advanced reduced-activation alloy

    NASA Astrophysics Data System (ADS)

    Noh, S. J.; Kim, H. S.; Byeon, W. J.; Shin, H. W.; Lee, Cheol Eui; Lee, S. K.

    2017-07-01

    We present the first experimental results of the deuterium retention and desorption behavior in an advanced reduced-activation alloy (ARAA) under development in Korea. For the in-situ measurement of desorbed gases from samples immediately after irradiation, a thermal desorption spectroscopy (TDS) system clustered with an inductively coupled plasma ion source has been built. Samples were and were not irradiated with helium ions at energies of 1.4, 3.5, and 5.0 keV and then continuously irradiated with 1.7-keV deuterium ions. TDS measurements were performed in situ immediately after deuterium irradiation and after exposure to air for one week. The amount of desorbed deuterium is the largest for the sample without helium irradiation from the TDS results measured in situ immediately after irradiation. Further, the amount of desorbed deuterium is significantly lowered when the helium energy is increased to 3.5 keV with no significant changes thereafter, indicating that the layer formed by implanted helium at near or deeper than the stopping range for 1.7-keV deuterium ions effectively acts as a barrier against deuterium diffusion into the depth. Because of the strong diffusivity of deuterium into the ambient atmosphere, the amounts of desorbed deuterium are greatly reduced for the samples without helium irradiation and with 1.4-keV helium irradiation after exposure to air for one week. In addition, our deuterium results for the ARAA are also compared with the results for F82H by other authors.

  14. Positron generation via two sequent laser pulses irradiating a solid aluminum target

    NASA Astrophysics Data System (ADS)

    Liu, Jian-Xun; Gan, Long-Fei; Ma, Yan-Yun; Zhao, Jun; Yang, Xiao-Hu; Yu, Tong-Pu; Zhuo, Hong-Bin; Shao, Fu-Qiu

    2017-08-01

    A scheme of two sequent laser pulses irradiating a thin solid aluminum target to generate electron-positron pairs via the multi-photon Breit-Wheeler (BW) process is proposed, in order to ease the usual requirement of the laser intensity. 2D and 3D particle-in-cell simulations show that the peak intensity of the laser pulses used in our scheme is only half of that in the case of one laser pulse with a peak intensity of 2 × 1023 W/cm2, but the positron yield is one order higher than that of the latter, which is around 3.7894 × 107 and has a maximal density of 3.134 × 1022 cm-3 when the time interval between the two pulses is set to Δt ≈ 2T0. Therefore, our scheme provides a helpful suggestion for the observation of the BW process in laboratories.

  15. Proton decoupling and recoupling under double-nutation irradiation in solid-state NMR

    NASA Astrophysics Data System (ADS)

    Takeda, Kazuyuki; Wakisaka, Asato; Takegoshi, K.

    2014-12-01

    The effect of 1H decoupling in magic-angle spinning solid-state NMR is studied under radiofrequency irradiation causing simultaneous nutations around a pair of orthogonal axes. Double-nutation with an arbitrary pair of nutation frequencies is implemented through modulation of the amplitude, phase, and frequency of the transmitting pulses. Similarity and difference of double-nutation decoupling and two-pulse phase-modulation decoupling schemes [A. E. Bennett, C. M. Rienstra, M. Auger, K. V. Lakshmi, and R. G. Griffin, J. Chem. Phys. 103, 6951-6958 (1995) and I. Scholz, P. Hodgkinson, B. H. Meier, and M. Ernst, J. Chem. Phys. 130, 114510 (2009)] are discussed. The structure of recoupling bands caused by interference of the 1H spin nutation with sample spinning is studied by both experiments and numerical simulations.

  16. Proton decoupling and recoupling under double-nutation irradiation in solid-state NMR

    SciTech Connect

    Takeda, Kazuyuki Wakisaka, Asato; Takegoshi, K.

    2014-12-14

    The effect of {sup 1}H decoupling in magic-angle spinning solid-state NMR is studied under radiofrequency irradiation causing simultaneous nutations around a pair of orthogonal axes. Double-nutation with an arbitrary pair of nutation frequencies is implemented through modulation of the amplitude, phase, and frequency of the transmitting pulses. Similarity and difference of double-nutation decoupling and two-pulse phase-modulation decoupling schemes [A. E. Bennett, C. M. Rienstra, M. Auger, K. V. Lakshmi, and R. G. Griffin, J. Chem. Phys. 103, 6951–6958 (1995) and I. Scholz, P. Hodgkinson, B. H. Meier, and M. Ernst, J. Chem. Phys. 130, 114510 (2009)] are discussed. The structure of recoupling bands caused by interference of the {sup 1}H spin nutation with sample spinning is studied by both experiments and numerical simulations.

  17. Magna-field irradiation and autologous marrow rescue in the treatment of pediatric solid tumors

    SciTech Connect

    Munoz, L.L.; Wharam, M.D.; Kaizer, H.; Leventhal, B.G.; Ruymann, R.

    1983-12-01

    Marrow ablative therapy has been given to pediatric patients with a variety of disseminated tumors. Eight patients with advanced neuroblastoma received autologous marrow reinfusion after intensive therapy. Three of eight are in continuous complete remission from 7 to 60 months. An additional four patients received allogeneic marrow transplantation and two remain in continuous complete response at 21 and 39 months. Intensive therapy and autologous marrow reinfusion have been applied to Ewing's sarcoma, but only preliminary results are available. Six patients with disseminated rhabdomyosarcoma and extra-osseous Ewing's sarcoma received conventional chemotherapy followed by sequential hemi-body irradiation. Four of six patients received autologous marrow rescue. Their median disease-free survival is 17 months. This preliminary experience demonstrates the feasibility of using marrow ablative therapy with autologous marrow transplantation in the treatment of pediatric solid tumors. Continuing Phase II studies are required to substantiate its efficacy.

  18. Directed fast electron beams in ultraintense picosecond laser irradiated solid targets

    SciTech Connect

    Ge, X. L.; Lin, X. X.; Yuan, X. H. E-mail: ytli@iphy.ac.cn; Sheng, Z. M.; Carroll, D. C.; Neely, D.; Gray, R. J.; Tresca, O.; McKenna, P.; Yu, T. P.; Chen, M.; Liu, F.; Zhuo, H. B.; Zielbauer, B.; and others

    2015-08-31

    We report on fast electron transport and emission patterns from solid targets irradiated by s-polarized, relativistically intense, picosecond laser pulses. A beam of multi-MeV electrons is found to be transported along the target surface in the laser polarization direction. The spatial-intensity and energy distributions of this beam are compared with the beam produced along the laser propagation axis. It is shown that even for peak laser intensities an order of magnitude higher than the relativistic threshold, laser polarization still plays an important role in electron energy transport. Results from 3D particle-in-cell simulations confirm the findings. The characterization of directional beam emission is important for applications requiring efficient energy transfer, including secondary photon and ion source development.

  19. Investigation of laser ion acceleration inside irradiated solid targets by neutron spectroscopy

    SciTech Connect

    Youssef, A.; Kodama, R.; Tampo, M.

    2006-03-15

    Origins and acceleration directions of accelerated ions inside solid LiF, CH-LiF, and LiF-CH targets irradiated by a 450 fs, 20 J, 1053 nm laser at an intensity of 3x10{sup 18} W/cm{sup 2} have been investigated by neutron spectroscopy. The irradiated targets generate neutrons through the reaction {sup 7}Li (p,n){sup 7}Be between accelerated protons and background {sup 7}Li ions inside the target. The produced neutron spectra observed from two different observation angles 20 deg. and 120 deg. to the target rear-side normal. From the measured and calculated spectra, by three-dimensional Monte Carlo code, the maximum energy, the total number, and the slope temperature of the accelerated ions are investigated. The results indicate that ions are not only accelerated from the front surface toward the rear surface, but also from the rear surface toward the front surface with comparable maximum energy and higher number.

  20. Direct depth distribution measurement of deuterium in bulk tungsten exposed to high-flux plasma

    NASA Astrophysics Data System (ADS)

    Taylor, C. N.; Shimada, M.

    2017-05-01

    Understanding tritium retention and permeation in plasma-facing components is critical for fusion safety and fuel cycle control. Glow discharge optical emission spectroscopy (GD-OES) is shown to be an effective tool to reveal the depth profile of deuterium in tungsten. Results confirm the detection of deuterium. A ˜46 μm depth profile revealed that the deuterium content decreased precipitously in the first 7 μm, and detectable amounts were observed to depths in excess of 20 μm. The large probing depth of GD-OES (up to 100s of μm) enables studies not previously accessible to the more conventional techniques for investigating deuterium retention. Of particular applicability is the use of GD-OES to measure the depth profile for experiments where high deuterium concentration in the bulk material is expected: deuterium retention in neutron irradiated materials, and ultra-high deuterium fluences in burning plasma environment.

  1. Modeling of secondary treated wastewater disinfection by UV irradiation: effects of suspended solids content.

    PubMed

    Brahmi, Mounaouer; Belhadi, Noureddine Hamed; Hamdi, Helmi; Hassen, Abdennaceur

    2010-01-01

    This work aimed to study UV-resistant strains of Pseudomonas aeruginosa, to propose a formulation of the kinetics of secondary treated wastewater disinfection and to underline the influence of suspended solids on the inactivation kinetics of these strains. Some investigations were carried out for the validation of some simulation models, from the simplest, the kinetics model of Chick-Watson reduced to first order, to rather complex models such as multi-kinetic and Collins-Selleck models. Results revealed that the involved processes of UV irradiation were too complex to be approached by a simplified formulation, even in the case of specific strains of microorganisms and the use of nearly constant UV radiation intensity. In fact, the application of Chick-Watson model in its original form is not representative of the kinetics of UV disinfection. Modification, taking into account the speed change during the disinfection process, has not significantly improved results. On the other hand, the application of Collins-Selleck model demonstrates that it was necessary to exceed a least dose of critical radiation to start the process of inactivation. To better explain the process of inactivation, we have assumed that the action of disinfectant on the survival of lonely microorganisms is faster than its action on suspended solids protected or agglomerated to each others. We can assume in this case the existence of two inactivation kinetics during the processes (parallel and independent) of the first-order. For this reason, the application of a new kinetic model by introducing a third factor reflecting the influence of suspended solids in water on disinfection kinetics appeared to be determinant for modeling UV inactivation of P. aeruginosa in secondary treated wastewater.

  2. Systemic irradiation for selected stage IV and recurrent pediatric solid tumors: method, toxicity, and preliminary results

    SciTech Connect

    Wharam, M.D.; Kaizer, H.; Leventhal, B.G.; Munoz, L.; Tutschka, P.J.; Santos, G.W.; Elfenbein, G.J.; Order, S.E.

    1980-02-01

    Eight patients with advanced pediatric solid tumors received either sequential upper and lower half-body irradiation (HBI) (7.5 rad/min to 500 rad total) or total body irradiation (TBI) (7.5 rad/min to 800 rad total) as part of two multimodality treatment regimens. All patients received combination chemotherapy; drugs were determined by the tumor type. The TBI regimen was selected for two patients who had progression of disease with conventional chemotherapy and for two patients with stage IV neuroblastoma. This intensive regimen consisted of bone marrow harvesting, followed by local radiation to gross disease, marrow-ablative chemotherapy, TBI, and re-infusion of the cryopreserved autologous marrow. Significant acute toxicity was followed by hematologic reconstitution in each patient within seven weeks. At this writing, two patients survived, one of whom is disease free two and one half years without maintenance chemotherapy. A less intensive, outpatient regimen was selected for four patients; three had a complete or good partial response to chemotherapy. The fourth patient had tumor-involved bone marrow not responsive to chemotherapy and was therefore ineligible for marrow cryopreservation and TBI. Each of these four patients received HBI after chemotherapy and local radiation to the primary and/or metastatic sites. Acute toxicity was limited to nausea and vomiting. Significant leukopenia and thrombocytopenia occurred in three patients. All four patients were alive 10 to 26 months post HBI. This pilot study demonstrates that chemotherapy can be integrated with local fractionated radiation, and systemic radiation given as HBI or TBI with acceptable toxicity; sufficient bone marrow stem cells can be harvested after conventional chemotherapy and then cryopreserved to permit hematologic reconstitution of the patient who receives marrow ablative therapy.

  3. Measurements of X-ray doses and spectra produced by picosecond laser-irradiated solid targets.

    PubMed

    Yang, Bo; Qiu, Rui; Yu, Minghai; Jiao, Jinlong; Lu, Wei; Yan, Yonghong; Zhang, Bo; Zhang, Zhimeng; Zhou, Weimin; Li, Junli; Zhang, Hui

    2017-05-01

    Experiments have shown that high-intensity laser interaction with a solid target can generate significant X-ray doses. This study was conducted to determine the X-ray doses and spectra produced for picosecond laser-irradiated solid targets. The photon doses and X-ray spectra in the laser forward and side directions were measured using an XG III ps 300 TW laser system. For laser intensities of 7×10(18)-4×10(19)W/cm(2), the maximum photon dose was 16.8 mSv at 50cm with a laser energy of ~153J on a 1-mm Ta target. The photon dose in the forward direction increased more significantly with increasing laser intensity than that in the side direction. For photon energies >300keV, the X-ray spectrum can be fit with an effective temperature distribution of the exponential form, dN/dE = k× exp(-E/Tx). The X-ray temperature Tx increased with the laser intensity in the forward direction with values of 0.46-0.75MeV. Tx was less strongly correlated with the laser intensity in the side direction with values of 0.29-0.32MeV. The escaping electron spectrum was also measured. The measured electron temperature was correlated with the electron temperature predicted by the ponderomotive law. The observations in this experiment were also investigated numerically. A good agreement was observed between the experimental and simulation results.

  4. Frequency Distribution of Second Solid Cancer Locations in Relation to the Irradiated Volume Among 115 Patients Treated for Childhood Cancer

    SciTech Connect

    Diallo, Ibrahima Haddy, Nadia; Adjadj, Elisabeth; Samand, Akhtar; Quiniou, Eric; Chavaudra, Jean; Alziar, Iannis; Perret, Nathalie; Guerin, Sylvie; Lefkopoulos, Dimitri; Vathaire, Florent de

    2009-07-01

    Purpose: To provide better estimates of the frequency distribution of second malignant neoplasm (SMN) sites in relation to previous irradiated volumes, and better estimates of the doses delivered to these sites during radiotherapy (RT) of the first malignant neoplasm (FMN). Methods and Materials: The study focused on 115 patients who developed a solid SMN among a cohort of 4581 individuals. The homemade software package Dos{sub E}G was used to estimate the radiation doses delivered to SMN sites during RT of the FMN. Three-dimensional geometry was used to evaluate the distances between the irradiated volume, for RT delivered to each FMN, and the site of the subsequent SMN. Results: The spatial distribution of SMN relative to the irradiated volumes in our cohort was as follows: 12% in the central area of the irradiated volume, which corresponds to the planning target volume (PTV), 66% in the beam-bordering region (i.e., the area surrounding the PTV), and 22% in regions located more than 5 cm from the irradiated volume. At the SMN site, all dose levels ranging from almost zero to >75 Gy were represented. A peak SMN frequency of approximately 31% was identified in volumes that received <2.5 Gy. Conclusion: A greater volume of tissues receives low or intermediate doses in regions bordering the irradiated volume with modern multiple-beam RT arrangements. These results should be considered for risk-benefit evaluations of RT.

  5. Time-resolved electron kinetics in swift heavy ion irradiated solids

    NASA Astrophysics Data System (ADS)

    Medvedev, N. A.; Rymzhanov, R. A.; Volkov, A. E.

    2015-09-01

    The event-by-event Monte Carlo model, TREKIS, was developed to describe the excitation of the electron subsystems of various solids by a penetrating swift heavy ion (SHI), the spatial spreading of generated fast electrons, and secondary electron and hole cascades. Complex dielectric function formalism is used to obtain relevant cross sections. This allows the recognition of fundamental effects resulting from the collective response of the electron subsystem of a target for excitation that is not possible within the binary collision approximation of these cross sections, e.g. the differences in the electronic stopping of an ion and in the electron mean free paths for different structures (phases) of a material. A systematic study performed with this model for different materials (insulators, semiconductors and metals) revealed effects which may be important for an ion track: e.g. the appearance of a second front of excess electronic energy propagation outwards from the track core following the primary front of spreading of generated electrons. We also analyze how the initial ballistic spatial spreading of fast electrons generated in a track turns to the diffusion ~10 fs after ion passage. Detailed time-resolved simulations of electronic subsystem kinetics helped in understanding the reasons behind enhanced silicon resistance to SHI irradiation in contrast to easily produced damage in this material by femtosecond laser pulses. We demonstrate that the fast spreading of excited electrons from the track core on a sub-100 fs timescale prevents the Si lattice from nonthermal melting in a relaxing SHI track.

  6. Cosmic ion irradiation and UV photolysis of solids in star forming regions .

    NASA Astrophysics Data System (ADS)

    Palumbo, M. E.; Baratta, G. A.; Spinella, F.

    The presence of icy grain mantles along the line of sight of star forming regions is clearly evidenced by infrared observations. Due to the presence of the protostar and of cosmic radiation, ices suffer from ion bombardment, UV photolysis and thermal annealing. Most of our knowledge on the physical and chemical properties of ices is based on the comparison between observations and laboratory experiments performed at low temperature (10-80 K). Experimental results show that after ion irradiation and UV photolysis the chemical composition and the structure of the sample is modified. Both more volatile and less volatile species are formed and if a C-bearing species is present in the original sample a refractory residue is formed. Eventually thermal annealing causes the sublimation of icy mantles. Thus molecules are released to the gas phase which could be enriched by species formed in the solid phase. Here we will discuss some recent laboratory experiments relevant to the knowledge of the physico-chemical properties of ices in star forming regions.

  7. Preparation of Cu-Ni/YSZ solid oxide fuel cell anodes using microwave irradiation

    NASA Astrophysics Data System (ADS)

    Islam, Shamiul; Hill, Josephine M.

    A microwave irradiation process is used to deposit Cu nanoparticles on the Ni/YSZ anode of an electrolyte-supported solid oxide fuel cell (SOFC). The reaction time in the microwave is only 15 s for the deposition of 6 wt% Cu (with respect to Ni) from a solution of Cu(NO 3) 2·3H 2O and ethylene glycol (HOCH 2CH 2OH). The morphology of the deposited Cu particles is spherical and the average size of the particles is less than 100 nm. The electrochemical performance of the microwave Cu-coated Ni/YSZ anodes is tested in dry H 2 and dry CH 4 at 1073 K, and the anodes are characterized with scanning electron microscopy, electrochemical impedance spectroscopy, and temperature-programmed oxidation. The results indicate that preparation of the anodes by the microwave technique produces similar performance trend as those reported for Cu-Ni/YSZ/CeO 2 anodes prepared by impregnation. Specifically, less carbon is formed on the Cu-Ni/YSZ than on conventional Ni/YSZ anodes when exposed to dry methane and the carbon that does form is more reactive.

  8. Modeling the EUV/UV irradiance within the FP7 SOLID Project

    NASA Astrophysics Data System (ADS)

    Haberreiter, Margit; Delouille, Veronique; Del Zanna, Giulio; Dammasch, Ingolf; Dominique, Marie; Dudok de Wit, Thierry; Ermolli, Ilaria; Jones, Andrew; Kretzschmar, Matthieu; Mampaey, Benjamin; Schaefer, Robert; Schmidtke, Gerhard; Schoell, Micha; Thuillier, Gerard; Verbeeck, Cis; Wieman, Seth; Woods, Tom; Schmutz, Werner

    2015-04-01

    The solar EUV irradiance has strong effects on the Earth's ionosphere and thermosphere. Here we present latest results for the EUV spectral range carried out within the European FP7 Project SOLID. Specifically, we model the SSI variations in the EUV spectral range based on the analysis of images obtained with SOHO/EIT, PROBA2/SWAP, and SDO/AIA. These images are segmented to regions of solar activity using the SPoCA tool. Moreover, with the SOLar MODeling code (SOLMOD) we calculate intensity spectra representing the intensity emitted by these regions. We present the latest set of reconstructions and compare it to available data, such as SOHO/SEM, PROBA2/LYRA, ISS/SOLAR/SOLACES, and SDO/EVE. Furthermore, we will present a probabilistic method to obtain a consistent composite from the available data. These results are an important for understanding the spectral variability in the EUV/UV and as well as its effect on the Earth's upper atmosphere.

  9. Irradiation effect on leaching behavior and form of heavy metals in fly ash of municipal solid waste incinerator.

    PubMed

    Nam, Sangchul; Namkoong, Wan

    2012-01-15

    Fly ash from a municipal solid waste incinerator (MSWI) is commonly classified as hazardous waste. High-energy electron beam irradiation systems have gained popularity recently as a clean and promising technology to remove environmental pollutants. Irradiation effects on leaching behavior and form of heavy metals in MSWI fly ash have not been investigated in any significant detail. An electron beam accelerator was used in this research. Electron beam irradiation on fly ash significantly increased the leaching potential of heavy metals from fly ash. The amount of absorbed dose and the metal species affected leaching behavior. When electron beam irradiation intensity increased gradually up to 210 kGy, concentration of Pb and Zn in the leachate increased linearly as absorbed dose increased, while that of Cu underwent no significant change. Concentration of Pb and Zn in the leachate increased up to 15.5% (10.7 mg/kg), and 35.6% (9.6 mg/kg) respectively. However, only 4.8% (0.3mg/kg) increase was observed in the case of Cu. The results imply that irradiation has significant effect on the leaching behavior of heavy metals in fly ash, and the effect is quite different among the metal species tested in this study. A commonly used sequential extraction analysis which can classify a metal species into five forms was conducted to examine any change in metal form in the irradiated fly ash. Notable change in metal form in fly ash was observed when fly ash was irradiated. Change in Pb form was much greater than that of Cu form. Change in metal form was related to leaching potential of the metals. Concentration of heavy metal in leachate was positively related to the exchangeable form which is the most mobile. It may be feasible to treat fly ash by electron beam irradiation for selective recovery of valuable metals or for pretreatment prior to conventional processes. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Kaon Electroproduction on Deuterium

    SciTech Connect

    David Abbott; Abdellah Ahmidouch, Pawel Ambrozewicz; Chris Armstrong; John Arrington; K. Assamagan; Kevin Bailey; Oliver K. Baker; Shelton Beedoe; Elizabeth Beise; Herbert Breuer; Roger Carlini; Jinseok Cha; G. Collins; C. Cothran; W.J. Cummings; Samuel Danagoulian; Fraser Duncan; Jim Dunne; Dipangkar Dutta; Tom Eden; Rolf Ent; Lars Ewell; H.T. Fortune; Haiyan Gao; Donald Geesaman; Kenneth Gustafsson; Paul Gueye; Jens-Ole Hansen; Wendy Hinton; Hal Jackson; Cynthia Keppel; Andi Klein; D. Koltenok; David Mack; Richard Madey; Pete Markowitz; C.J. Martoff; David Meekins; Joseph Mitchell; R. Mohring; Hamlet Mkrtchyan; S.K. Mtingwa; Tom O'Neill; Gabriel Niculescu; Ioana Niculescu; Dave Potterveld; John Price; Philip Roos; Brian Raue; J.J. Reidy; Juerg Reinhold; G. Savage; Reyad Sawafta; J.P. Schiffer; Ralph Segel; Stepan Stepanyan; V. Tadevosian; Liguang Tang; B. Terburg; Stephen Wood; Chen Yan; Ben Zeidman; Beni Zihlmann

    1998-08-01

    Kaon electroproduction on deuterium and hydrogen targets has been measured at beam energies of 3.245 and 2.445GeV and momentum transfer Q{sup 2}=0.38 and O.5(GeV/c ){sup 2} Associated production off a proton in the deuteron exhibits a quasifree production mechanism. The electroproduction of a Sigma - off the neutron could be extracted for the first time with reasonable errors.

  11. Direct depth distribution measurement of deuterium in bulk tungsten exposed to high-flux plasma

    DOE PAGES

    Taylor, Chase N.; Shimada, M.

    2017-05-08

    Understanding tritium retention and permeation in plasma-facing components is critical for fusion safety and fuel cycle control. Glow discharge optical emission spectroscopy (GD-OES) is shown to be an effective tool to reveal the depth profile of deuterium in tungsten. Results confirm the detection of deuterium. Furthermore, a ~46 µm depth profile revealed that the deuterium content decreased precipitously in the first 7 µm, and detectable amounts were observed to depths in excess of 20 µm. The large probing depth of GD-OES (up to 100s of µm) enables studies not previously accessible to the more conventional techniques for investigating deuterium retention.more » Of particular applicability is the use of GD-OES to measure the depth profile for experiments where high diffusion is expected: deuterium retention in neutron irradiated materials, and ultra-high deuterium fluences in burning plasma environment.« less

  12. Poly(ethylene oxide) irradiated in the solid state, melt and aqueous solution—a DSC and WAXD study

    NASA Astrophysics Data System (ADS)

    Jurkin, Tanja; Pucić, Irina

    2012-09-01

    Interactions of the aggregate state of poly(ethylene oxide), PEO, and γ-irradiation conditions (total dose, atmosphere) on its thermal and crystalline properties were investigated by DSC and WAXD taking into account sample molecular mass and form. In PEO irradiated in the solid state and in the presence of oxygen, chain scission dominated over concurrent crosslinking up to 200 kGy, particularly in PEO powders, due to a large surface being in contact with air. In solid samples the degree of crystallinity and crystallite size increased with the dose up to 50 kGy, probably not just due to partial crystallization upon degradation of amorphous phase, but to recrystallization of broken tie molecules. The least changes in crystallinity and phase transformation temperatures occurred in solid films. A substantial decrease in crystallinity and transformation temperatures without the initial crystallinity increase was achieved in samples that were amorphous on irradiation, at temperatures above the PEO melting temperature and in aqueous solutions. Radiation crosslinking of the PEO aqueous solution in an inert atmosphere is the most suitable way to obtain a lower degree of crystallinity and phase transformation temperatures while preserving mechanical properties.

  13. Effect of supplemental UV-A irradiation in solid-state lighting on the growth and phytochemical content of microgreens

    NASA Astrophysics Data System (ADS)

    Brazaitytė, A.; Viršilė, A.; Jankauskienė, J.; Sakalauskienė, S.; Samuolienė, G.; Sirtautas, R.; Novičkovas, A.; Dabašinskas, L.; Miliauskienė, J.; Vaštakaitė, V.; Bagdonavičienė, A.; Duchovskis, P.

    2015-01-01

    In this study, we sought to find and employ positive effects of UV-A irradiation on cultivation and quality of microgreens. Therefore, the goal of our study was to investigate the influence of 366, 390, and 402 nm UV-A LED wavelengths, supplemental for the basal solid-state lighting system at two UV-A irradiation levels on the growth and phytochemical contents of different microgreen plants. Depending on the species, supplemental UV-A irradiation can improve antioxidant properties of microgreens. In many cases, a significant increase in the investigated phytochemicals was found under 366 and 390 nm UV-A wavelengths at the photon flux density (12.4 μmol m-2 s-1). The most pronounced effect of supplemental UV-A irradiation was detected in pak choi microgreens. Almost all supplemental UV-A irradiation treatments resulted in increased leaf area and fresh weight, in higher 2,2-diphenyl-1-picrylhydrazyl free-radical scavenging activity, total phenols, anthocyanins, ascorbic acid, and α-tocopherol.

  14. Dechlorination of organochloride waste mixture by microwave irradiation before forming solid recovered fuel.

    PubMed

    Liu, Zhen; Wang, Han-Qing; Zhang, Xiao-Dong; Liu, Jian-Wen; Zhou, Yue-Yun

    2016-11-22

    In order to form a modified solid recovered fuel (SRF) with low chlorine content, high calorific value and well combustion performance, low temperature microwave irradiation was applied to remove the chlorine of the organochloride waste mixture before they were mixed to form SRF. The optimizing conditions of final temperature, microwave absorbents and heating rate were also detected to obtain high dechlorination ratio and high ratio of hydrogen chloride (HCl) to volatiles. In the temperature range of 220-300°C, 280°C would be chose as the optimal low microwave modified temperature concerning at which the dechlorination ratio was high and ratio of HCl to volatiles was relatively high as well; The use of microwave absorbents of graphite and silicon carbide (SiC) had a pronounced effect on the dechlorination of organochloride waste mixture, and the dechlorination ratio was increased significantly which could be reached to 87%, almost 20% higher than absorbent absent sample; The heating rate should set be not too fast nor too slow, and there was no big difference between the heating rate of 13°C/min and 15°C/min; The content of Cl of modified SRF is dramatically decreased and reaches to a low level 0.328%. Hence, the modified SRF can be ascended from the third class to the second class according to the Finland chlorine Classes I-III. Moreover, the combustibility of modified SRF was substantial improved compared to the traditional SRF. The low heating value was almost 20.56MJ/kg which is close to the LHV of lignite coal and bituminous coal in China, and it increased by 60% over that of traditional SRF. Removing chlorine of organochloride waste mixture before they are mixed with other kinds of combustible waste to form a modified SRF which is expected to be an alternative fuel for combustion in the future.

  15. Atomic displacement in solids: analysis of the primary event and the collision cascade. Part I: Neutron and positive ion irradiation

    NASA Astrophysics Data System (ADS)

    de Almeida, P.; Räisänen, J.

    2005-05-01

    A modern, mathematical-physics introduction to the analytical problem of atomic displacement in solids which is both technically adequate and relevant to an introductory graduate students' curriculum in radiation damage theory is reported. The problematic of atomic displacement in solids is introduced didactically, deriving first the primary event (that is, the formation of the primary knock-on atom) and then building on that specific set of results in order to extend their basics to secondary, tertiary and higher-order progeny—the collision cascade—for both neutrons and positive ions, namely, their average damage functions, displacement cross-sections and energy spectra. A comparison of atomic displacement in solids under neutron and positive ion irradiation is discussed in terms of the physical concept of concentration of displaced atoms (or displacement dose).

  16. Astration of cosmological deuterium

    NASA Technical Reports Server (NTRS)

    Clayton, D. D.

    1985-01-01

    Attention is given to the degree of primordial deuterium's astration through the continuous galactic processes of star formation and chemical evolution. Exact analytic solutions are given for galactic chemical evolution when infall of constant composition occurs at a rate, f(t), which is presently defined. Solutions are given for the linear model with instantaneous recycling and with constant return fraction R. The results suggest that big bang D/H was at least three times larger than the largest values observed in today's solar neighborhood, and even larger if matter falling into the disk is already astrated.

  17. Gas swelling and deuterium distribution in beryllium implanted with deuterium ions

    SciTech Connect

    Chernikov, V.N.; Alimov, V.Kh.; Zakharov, A.P.

    1995-09-01

    An extensive TEM study of the microstructure of Be TIP-30 irradiated with 3 and 10 keV D ions up to fluences, {Phi}, in the range from 3 x 10{sup 20} to 8 x 10{sup 21} D/m{sup 2} at temperatures T{sub irr} = 300 K, 500 K and 700 K has been carried out. Depth distributions of deuterium in the form of separate D atoms and D{sub 2} molecules have been investigated by means of SIMS and RGA methods, correspondingly. D ion irradiation is accompanied by blistering and gives rise to different kind of destructions depending mainly on the irradiation temperature. Irradiation with D ions at 300 K leads to the formation of tiny highly pressurized D{sub 2} bubbles reminiscent of He bubbles in Be. Under 3 keV D ion irradiation D{sub 2} bubbles ({bar r}{sub b} {approx} 0.7 nm) appear at a fluence as low as 3x10{sup 20} D/m{sup 2}. Irradiation at 500 K results in the development, along with relatively small facetted bubbles, of larger oblate gas-filled cavities accumulating most of injected D atoms and providing for much higher gas swelling values as compared to irradiation at 300 K. The increase of D and/or T{sub irr}, to 700 K causes the further coarsening of large cavities which are transformed into sub-surface labyrinth structures. D and He ion implantation leads to the enhanced growth of porous microcrystalline layers of c.p.h.-BeO oxide with a microstructure which differs considerably from that of oxide layers on electropolished surfaces of Be. Based on the analysis of experimental data questions of deuterium reemission, thermal desorption and trapping in Be have been discussed in detail.

  18. Effects of zirconium element on the microstructure and deuterium retention of W-Zr/Sc2O3 composites.

    PubMed

    Chen, Hongyu; Luo, Laima; Chen, Jingbo; Zan, Xiang; Zhu, Xiaoyong; Xu, Qiu; Luo, Guangnan; Chen, Junling; Wu, Yucheng

    2016-09-06

    Dense W and W-Zr composites reinforced with Sc2O3 particles were produced through powder metallurgy and subsequent spark plasma sintering (SPS) at 1700 °C and 58 MPa. Results showed that the W-1vol.%Zr/2vol.%Sc2O3 composites exhibited optimal performance with the best relative density of up to 98.93% and high Vickers microhardness of approximately 583 Hv. The thermal conductivity of W-Zr/Sc2O3 composites decreased initially and then increased as the Zr content increased. The moderate Zr alloying element could combine well with Sc2O3 particles and W grains and form a solid solution. However, excess Zr element leads to agglomeration in the grain boundaries. W-1vol.%Zr/2vol.%Sc2O3 composite had a good deuterium irradiation resistance very closing to pure tungsten compared with the other Zr element contents of composites. Under 500 K, D2 retention and release of them were similar to those of commercial tungsten, even lower between 400 K to 450 K. Pre-irradiation with 5 keV-He(+) ions to a fluence of 1 × 10(21) He(+)/m(2) resulted in an increase in deuterium retention (deuterium was implanted after He(+) irradiation), thereby shifting the desorption peak to a high temperature from 550 K to 650 K for the W-1vol.%Zr/2vol.%Sc2O3 composite.

  19. Effects of zirconium element on the microstructure and deuterium retention of W–Zr/Sc2O3 composites

    PubMed Central

    Chen, Hongyu; Luo, Laima; Chen, Jingbo; Zan, Xiang; Zhu, Xiaoyong; Xu, Qiu; Luo, Guangnan; Chen, Junling; Wu, Yucheng

    2016-01-01

    Dense W and W–Zr composites reinforced with Sc2O3 particles were produced through powder metallurgy and subsequent spark plasma sintering (SPS) at 1700 °C and 58 MPa. Results showed that the W–1vol.%Zr/2vol.%Sc2O3 composites exhibited optimal performance with the best relative density of up to 98.93% and high Vickers microhardness of approximately 583 Hv. The thermal conductivity of W–Zr/Sc2O3 composites decreased initially and then increased as the Zr content increased. The moderate Zr alloying element could combine well with Sc2O3 particles and W grains and form a solid solution. However, excess Zr element leads to agglomeration in the grain boundaries. W–1vol.%Zr/2vol.%Sc2O3 composite had a good deuterium irradiation resistance very closing to pure tungsten compared with the other Zr element contents of composites. Under 500 K, D2 retention and release of them were similar to those of commercial tungsten, even lower between 400 K to 450 K. Pre-irradiation with 5 keV-He+ ions to a fluence of 1 × 1021 He+/m2 resulted in an increase in deuterium retention (deuterium was implanted after He+ irradiation), thereby shifting the desorption peak to a high temperature from 550 K to 650 K for the W–1vol.%Zr/2vol.%Sc2O3 composite. PMID:27597314

  20. Effects of zirconium element on the microstructure and deuterium retention of W–Zr/Sc2O3 composites

    NASA Astrophysics Data System (ADS)

    Chen, Hongyu; Luo, Laima; Chen, Jingbo; Zan, Xiang; Zhu, Xiaoyong; Xu, Qiu; Luo, Guangnan; Chen, Junling; Wu, Yucheng

    2016-09-01

    Dense W and W–Zr composites reinforced with Sc2O3 particles were produced through powder metallurgy and subsequent spark plasma sintering (SPS) at 1700 °C and 58 MPa. Results showed that the W–1vol.%Zr/2vol.%Sc2O3 composites exhibited optimal performance with the best relative density of up to 98.93% and high Vickers microhardness of approximately 583 Hv. The thermal conductivity of W–Zr/Sc2O3 composites decreased initially and then increased as the Zr content increased. The moderate Zr alloying element could combine well with Sc2O3 particles and W grains and form a solid solution. However, excess Zr element leads to agglomeration in the grain boundaries. W–1vol.%Zr/2vol.%Sc2O3 composite had a good deuterium irradiation resistance very closing to pure tungsten compared with the other Zr element contents of composites. Under 500 K, D2 retention and release of them were similar to those of commercial tungsten, even lower between 400 K to 450 K. Pre-irradiation with 5 keV-He+ ions to a fluence of 1 × 1021 He+/m2 resulted in an increase in deuterium retention (deuterium was implanted after He+ irradiation), thereby shifting the desorption peak to a high temperature from 550 K to 650 K for the W–1vol.%Zr/2vol.%Sc2O3 composite.

  1. gamma. -irradiated sewage solids in diets for sheep: nutritive evaluations and long-term assessments of possible toxicants

    SciTech Connect

    Sanson, D.W.

    1983-01-01

    Air-dried solids from primary (undigested) sewage sludge were collected at Las Cruces, New Mexico (a non-industrial town with population about 50,000). Bagged sewage solids were ..gamma..-irradiated (1 megarad dosage) to kill parasites and pathogenic organisms and evaluated as prospective feedstuffs for sheep. Pelleted, complete diets for gestating-lactating fine-wool ewes and for their growing-finishing lambs were formulated to be isonitrogenous with either 3.5% cottonseed meal (conventional diet) or 7% sewage solids (experimental diet). Digestibility of organic matter and crude protein, and biological value of nitrogen, did not differ (P > .05) between diets, as determined with wethers. Wether lambs fed to slaughter with conventional or experimental diets did not differ (P > .05) in rate of gain, carcass characteristics, element concentrations in blood and serum chemistry profiles, although liver Cu and kidney Pb levels were increased (P < .05) about 1.6-fold by sewage solids. Element contents of spleen and muscles did not differ (P > .05) due to diets. These studies confirm previous research at New Mexico State University which indicates that dried solids from municipal (primary) sludge provide nutritive benefits to sheep with risks of toxicity and heavy metal accumulation that appear tolerable where managed properly.

  2. Stabilization and isomerization of radical cations generated by fast electron irradiation of unsaturated organic molecules in a solid argon matrix

    NASA Astrophysics Data System (ADS)

    Feldman, V. I.; Sukhov, F. F.; Orlov, A. Yu.; Tyulpina, I. V.; Ivanchenko, V. K.

    2006-01-01

    Matrix isolation EPR spectroscopy was used to study the fate of "hot" unsaturated radical cations produced by fast electron irradiation in solid argon. It was found that the radical cations of cis-2-butene, trans-2-butene and ethyl vinyl ether resulting from highly exothermic hole transfer (excess energy>6 eV) underwent effective relaxation in an argon matrix. 1-Butene radical cation exhibits isomerization to cis-2-butene radical cation. The role of molecular structure of organic radical cations in excess energy relaxation is discussed.

  3. Dielectronic Satellites and Auger Electron Heating: Irradiation of Solids by Intense XUV-Free Electron Laser Radiation

    NASA Astrophysics Data System (ADS)

    Petitdemange, F.; Rosmej, F. B.

    Auger electron heating of dense matter that is driven by irradiation of solids with intense XUV/X-ray Free Electron Laser radiation permits studying the dielectronic capture channels that are usually closed in standard atomic physics investigations (like, e.g., in accelerators, EBITS, tokamaks, astrophysics). After disintegration of crystalline order dense strongly coupled plasma is formed where dielectronic capture coupled to excited states is identified as the primary population source of autoionizing hole states. We demonstrate that excited states coupling of the inverse Auger effect changes entirely the known picture of dielectronic satellite emission.

  4. Investigation of gamma-irradiated vegetable seeds with high-resolution solid-state 13C NMR.

    PubMed

    Bardet, Michel; Maron, Sébastien; Foray, Marie Françoise; Berger, Maurice; Guillermo, Armel

    2004-04-01

    13C solid-state NMR was used to investigate the effects of gamma radiation on vegetable seeds, Pisum sativum and Latuca sativa, at absorbed doses that inhibit their germination. By combining single-pulse excitation and cross-polarization experiments under magic angle spinning, both liquid and solid domains of seeds can be characterized. We showed that the liquid domains, mostly made of triacylglycerols (TAG), of vegetable seeds are not sensitive to radiation. The main structural changes have been observed in the embryonic axes of seeds when the seeds are water-imbibed before irradiation. These results rule out a starting hypothesis concerning the potential role of TAG contained in oil bodies as a potential source of aldehydes that could further react with DNA moiety.

  5. Muon capture in deuterium

    NASA Astrophysics Data System (ADS)

    Ricci, P.; Truhlík, E.; Mosconi, B.; Smejkal, J.

    2010-06-01

    Model dependence of the capture rates of the negative muon capture in deuterium is studied starting from potential models and the weak two-body meson exchange currents constructed in the tree approximation and also from an effective field theory. The tree one-boson exchange currents are derived from the hard pion chiral Lagrangians of the NΔπρωa system. If constructed in conjunction with the one-boson exchange potentials, the capture rates can be calculated consistently. On the other hand, the effective field theory currents, constructed within the heavy baryon chiral perturbation theory, contain a low energy constant d that cannot be extracted from data at the one-particle level nor determined from the first principles. Comparative analysis of the results for the doublet transition rate allows us to extract the constant d.

  6. Deuterium in carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Kolodny, Y.; Kerridge, J. F.; Kaplan, I. R.

    1980-01-01

    Hydrogen isotopic compositions in seven carbonaceous chondrites lie in the range -70 to +771 per thousand relative to standard mean ocean water. These values decrease, to a range from -145 to +219 per thousand, after low-temperature oxidation in an oxygen plasma. Deuterium enrichment is therefore concentrated in the organic matter, the hydrous silicates probably lying close to the terrestrial range for such material. Calculated values for delta D of the organic fraction are +450 per thousand for Orgueil and Ivuna and up to +1600 per thousand for Renazzo. These enrichments, at least for Orgueil and Ivuna, suggest equilibration with protosolar hydrogen at very low temperatures. Assuming a value of 2.5 x 10 to the -5th for the protosolar D/H ratio, nominal equilibration temperatures of 230 K for silicates and 180 K for organic matter may be derived.

  7. Deuterium uptake in boronized ATJ graphite walls of NSTX-U

    NASA Astrophysics Data System (ADS)

    Dominguez, Javier; Bedoya, Felipe; Krstic, Predrag; Allain, Jean Paul; Irle, Stephan; Skinner, Charles; Kaita, Robert; Koel, Bruce

    2016-10-01

    We present a study of the role of boron and oxygen in the chemistry of deuterium retention in boronized ATJ graphite irradiated by a deuterium plasma. The experimental results were obtained by the first in vacuo X-ray Photoelectron Spectroscopy (XPS) measurements at the National Spherical Torus Experiment Upgrade (NSTX-U). The subtle interplay of boron, carbon, oxygen and deuterium chemistry is explained by reactive molecular dynamics simulation, verified by quantum-classical molecular dynamics and successfully compared to the measured data. The calculations deciphered the roles of oxygen and boron for the deuterium retention and predict deuterium uptake by a boronized carbon surface of 90% close in value to that previously predicted for a lithiated and oxidized carbon surface. CONACyT (JD), USDOE FES Grants (PSK and BK), USDOE BES/FES Grant (JPA and FB).

  8. Using chemo-drugs or irradiation to break immune tolerance and facilitate immunotherapy in solid cancer.

    PubMed

    Zheng, Yawen; Dou, Yan; Duan, Lili; Cong, Changsheng; Gao, Aiqin; Lai, Qinghua; Sun, Yuping

    2015-03-01

    The immunity is dual host-protective and tumor-promoting in cancer development and progression. Many immune suppressive cells and cytokines in microenvironment can prevent cytotoxic T lymphocytes (CTL) and natural killer cells (NK) from killing tumor cells. Chemotherapy drugs and irradiation have been reported helpful in breaking immune tolerance and creating microenvironment for adoptive cell therapy. Low-dose cyclophosphamide or gemcitabine therapy can selectively deplete T regulatory cells (Treg). Paclitaxel can alter cytokine network at the tumor site, and 5-fluorouracil shows a pronounced effect on myeloid-derived suppressor cells (MDSC) depletion. Local tumor irradiation and total body irradiation (TBI) can also affect tumor microenvironment and facilitate immunotherapy. In this review, we summarize the particular effects of these agents and methods on immunomodulation, as well as their potential values in immunotherapy. The combination with immunotherapy represents a novel therapeutic strategy.

  9. Physicochemical Processes on Ice Dust Towards Deuterium Enrichment

    NASA Astrophysics Data System (ADS)

    Watanabe, Naoki

    2017-06-01

    Water and some organic molecules were found to be deuterium enriched toward various astronomical targets. Understanding the deuterium-fractionation process pertains directly to know how and when molecules are created. Although gas phase chemistry is certainly important for deuterium enrichment, the role of physicochemical processes on the dust surfaces should be also considered. In fact, the extreme deuterium enrichment of formaldehyde and methanol requires the dust grain-surface process. In this context, we have performed a series of experiments on the formation of deuterated species of water and simple organic molecules. From the results of these experiments and related works, I will discuss the key processes for the deuterium enrichment on dust. For deuterium chemistry, another important issue is the ortho-to-para ratio (OPR) of H_{2}, which is closely related to the formation of H_{2}D^{+} and thus the deuterium fractionation of molecules in the gas phase. Because the radiative nuclear spin conversion of H_{2} is forbidden, the ortho-para conversion is very slow in the gas phase. In contrast, it was not obvious how the nuclear spins behave on cosmic dust. Therefore, it is desirable to understand how the OPR of H_{2} is determined on the dust surfaces. We have tackled this issue experimentally. Using experimental techniques of molecular beam, photostimulated-desorption, and resonance-enhanced multiphoton ionization, we measured the OPRs of H_{2} photodesorbed from amorphous solid water at around 10 K, which is an ice dust analogue. It was first demonstrated that the rate of spin conversion from ortho to para drastically increases from 2.4 × 10^{-4} to 1.7 × 10^{-3} s^{-1} within the very narrow temperature window of 9.2 to16 K. The observed strong temperature cannot be explained by solely state-mixing models ever proposed but by the energy dissipation model via two phonon process. I will present our recent experiments regarding this.

  10. Core Deuterium Fusion and Radius Inflation in Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Jaikumar, Prashanth; Rachid Ouyed

    2016-06-01

    Several laboratory-based studies have shown that the Deuterium fusion cross-section is enhanced in a solid deuterated target as compared to a gas target, attributable to enhanced mobility of deuterons in a metal lattice. As an application, we propose that, for core temperatures and compositions characterizing hot Jupiters, screened Deuterium fusion can occur deep in the interior, and show that the amount of radius inflation from this effect can be important if there is sufficient rock-ice in the core. The mechanism of screened Deuterium fusion, operating in the above temperature range, is generally consistent with the trend in radius anomaly with planetary equilibrium temperature. We also explore the trend with planetary mass using a simple analytic model.

  11. Irradiated ignition of solid materials in reduced pressure atmosphere with various oxygen concentrations for fire safety in space habitats

    NASA Astrophysics Data System (ADS)

    Nakamura, Y.; Aoki, A.

    Effects of sub-atmospheric ambient pressure and oxygen content on irradiated ignition characteristics of solid combustibles were examined experimentally in order to elucidate the flammability and chance of fire in depressurized systems and give ideas for the fire safety and fire fighting strategies for such environments. Thin cellulosic paper was used as the solid combustible since cellulose is one of major organic compounds and flammables in the nature. Applied atmospheres consisted of inert gases (either CO 2 or N 2) and oxygen at various mixture ratios. Total ambient pressure ( P) was varied from 101 kPa (standard atmospheric pressure, P0) to 20 kPa. Ignition was initiated by external thermal radiation with CO 2 laser (10 W total; 21.3 W/cm 2 of the corresponding peak flux) onto the solid surface. Thermal degradation of the solid produced combustible gaseous products (e.g. CO, H 2, or other low weight of HCs) and these products mixed with ambient oxygen to form the combustible mixture over the solid. Heat transfer from the irradiated surface into the mixture accelerated the exothermic reaction in the gas phase and finally thermal runaway (ignition) was achieved. A digital video camera was used to analyze the ignition characteristics. Flammability maps in partial pressure of oxygen (ppO 2) and normalized ambient pressure ( P/ P0) plane were made to reveal the fire hazard in depressurized environments. Results showed that a wider flammable range was obtained in sub-atmospherics conditions. In middle pressure range (101-40 kPa), the required ppO 2 for ignition decreased almost linearly as the total pressure decreased, indicating that higher fire risk is expected. In lower pressure range (<40 kPa), the required partial pressure of oxygen increased dramatically, then ignition was eventually not achieved at pressures less than 20 kPa under the conditions studied here. The findings suggest that it might be difficult to satisfy safety in space agriculture since it has

  12. Pulsed deuterium lithium nuclear reactor

    SciTech Connect

    Fischer, A.G.

    1980-01-08

    A nuclear reactor that burns hydrogen bomb material 6-lithium deuterotritide to helium in successive microexplosions which are ignited electrically and enclosed by this same molten material, and that permits the conversion of the reaction heat into useful electrical power. A specially-constructed high-current pulse machine is discharged via a thermally-preformed highly conducting path through a mass of the molten salt 6lid1-xtx (0deuterium bubbles. The heat shock is buffered by partial melting of the external solid crust. The reaction heat is carried by the liquid metal of the external cooling jacket to the heat exchanger of the associated turbo-generator. Every few seconds, a new pulse can take place.

  13. On the colors of Jupiter's satellite Io - Irradiation of solid sulfur at 77 K

    NASA Technical Reports Server (NTRS)

    Steudel, R.; Holdt, G.; Young, A. T.

    1986-01-01

    The colors of seven sulfur allotropes at 77 K have been investigated both before and after irradiation by a high-pressure mercury lamp. S8 is white at 77 K but turns intense yellow within a few minutes on irradiation through quartz or DURAN. On warming, the yellow species (presumably chain-like sulfur diradicals characterized by an absorption at 430 nm) decomposes near 260 K and polymeric sulfur (S-infinity) is formed; the sample color changes gradually to the very similar color of an S8-S-infinity mixture, resulting in no visually detectable color change with temperatures from 77 K to 260 K. This is consistent with the lack of posteclipse brightening on Io. Other sulfur forms also turn intense yellow (S7, S10), grayish yellow (S12, S20, S-infinity), or brownish yellow (S6) on irradiation at 77 K, and these colors also change to the normal colors of the starting materials on warming to 298 K. It is suggested that the yellowish features on Io are caused by the effect of solar radiation on elemental sulfur. The yellow color thus produced may subsequently be modified by deposits of SO2 frosts and volcanic ash.

  14. On the colors of Jupiter's satellite Io - Irradiation of solid sulfur at 77 K

    NASA Astrophysics Data System (ADS)

    Steudel, R.; Holdt, G.; Young, A. T.

    1986-04-01

    The colors of seven sulfur allotropes at 77 K have been investigated both before and after irradiation by a high-pressure mercury lamp. S8 is white at 77 K but turns intense yellow within a few minutes on irradiation through quartz or DURAN. On warming, the yellow species (presumably chain-like sulfur diradicals characterized by an absorption at 430 nm) decomposes near 260 K and polymeric sulfur (S-infinity) is formed; the sample color changes gradually to the very similar color of an S8-S-infinity mixture, resulting in no visually detectable color change with temperatures from 77 K to 260 K. This is consistent with the lack of posteclipse brightening on Io. Other sulfur forms also turn intense yellow (S7, S10), grayish yellow (S12, S20, S-infinity), or brownish yellow (S6) on irradiation at 77 K, and these colors also change to the normal colors of the starting materials on warming to 298 K. It is suggested that the yellowish features on Io are caused by the effect of solar radiation on elemental sulfur. The yellow color thus produced may subsequently be modified by deposits of SO2 frosts and volcanic ash.

  15. Effect of radiation on solid paracetamol: ESR identification and dosimetric features of gamma-irradiated paracetamol

    NASA Astrophysics Data System (ADS)

    Polat, M.; Korkmaz, M.

    2006-01-01

    In the present work, electron spin resonance (ESR) identification of gamma-irradiated paracetamol and its potential use as a normal and/or accidental dosimetric material were investigated in the dose range of 2.5-25 kGy. Both unirradiated paracetamol and mechanically ground vermidon samples exhibited a weak single resonance line at g = 2.0049 +/- 0.0006 and had Delta H-pp = 0.6 +/- 0.02 mT. Gamma irradiation produced an increase in signal intensity with a small hyperfine splitting in both paracetamol and vermidon and many weak resonance lines on both sides of a central line in the case of vermidon. Dose-response curves associated with central line of paracetamol and vermidon were found to follow polynomial and linear function, respectively. Simulation calculations based on the room temperature ESR intensity data of the paracetamol sample irradiated at 10 kGy were performed to determine the structure and spectral parameters of the radiation-induced radical species involved in the formation of the experimental ESR spectrum of paracetamol.

  16. On the colors of Jupiter's satellite Io - Irradiation of solid sulfur at 77 K

    NASA Technical Reports Server (NTRS)

    Steudel, R.; Holdt, G.; Young, A. T.

    1986-01-01

    The colors of seven sulfur allotropes at 77 K have been investigated both before and after irradiation by a high-pressure mercury lamp. S8 is white at 77 K but turns intense yellow within a few minutes on irradiation through quartz or DURAN. On warming, the yellow species (presumably chain-like sulfur diradicals characterized by an absorption at 430 nm) decomposes near 260 K and polymeric sulfur (S-infinity) is formed; the sample color changes gradually to the very similar color of an S8-S-infinity mixture, resulting in no visually detectable color change with temperatures from 77 K to 260 K. This is consistent with the lack of posteclipse brightening on Io. Other sulfur forms also turn intense yellow (S7, S10), grayish yellow (S12, S20, S-infinity), or brownish yellow (S6) on irradiation at 77 K, and these colors also change to the normal colors of the starting materials on warming to 298 K. It is suggested that the yellowish features on Io are caused by the effect of solar radiation on elemental sulfur. The yellow color thus produced may subsequently be modified by deposits of SO2 frosts and volcanic ash.

  17. Tritium trapping in silicon carbide in contact with solid breeder under high flux isotope reactor irradiation

    SciTech Connect

    H. Katsui; Y. Katoh; A. Hasegawa; M. Shimada; Y. Hatano; T. Hinoki; S. Nogami; T. Tanaka; S. Nagata; T. Shikama

    2013-11-01

    The trapping of tritium in silicon carbide (SiC) injected from ceramic breeding materials was examined via tritium measurements using imaging plate (IP) techniques. Monolithic SiC in contact with ternary lithium oxide (lithium titanate and lithium aluminate) as a ceramic breeder was irradiated in the High Flux Isotope Reactor (HFIR) in Oak Ridge, Tennessee, USA. The distribution of photo-stimulated luminescence (PSL) of tritium in SiC was successfully obtained, which separated the contribution of 14C ß-rays to the PSL. The tritium incident from ceramic breeders was retained in the vicinity of the SiC surface even after irradiation at 1073 K over the duration of ~3000 h, while trapping of tritium was not observed in the bulk region. The PSL intensity near the SiC surface in contact with lithium titanate was higher than that obtained with lithium aluminate. The amount of the incident tritium and/or the formation of a Li2SiO3 phase on SiC due to the reaction with lithium aluminate under irradiation likely were responsible for this observation.

  18. Interstellar Deuterium Chemistry

    NASA Technical Reports Server (NTRS)

    Sandford, S. A.

    2003-01-01

    The presence of isotopic anomalies is the most unequivocal demonstration that meteoritic material contains circumstellar or interstellar components. In the case of organic compounds in meteorites and interplanetary dust particles (IDPs), the most useful isotopic tracer of interstellar components has been deuterium (D) excesses. In some cases these enrichments are seen in bulk meteoritic materials, but D enrichments have also been observed in meteoritic subfractions and even within specific classes of molecular species, such as amino and carboxylic acids. These anomalies are not thought to be the result of nucleosynthetic processes, but are instead ascribed to chemical and physical processes occurring in the interstellar medium (ISM). The traditional explanation of these D excesses has been to invoke the presence of materials made in the ISM by low temperature gas phase ion-molecule reactions. Indeed, the DM ratios seen in the simple interstellar gas phase molecules in cold dense clouds amenable to measurement using radio spectral techniques are generally considerably higher than the values seen in enriched Solar System materials. However, the true linkage between the DM ratios in interstellar and meteoritic materials is obscured by several effects. First, current observations of D enrichment in the ISM have been made of only a few simple molecules, molecules that are not the main carriers of D in Solar System materials. Second, some of the interstellar D enrichment is likely to reside on labile moieties that will have exchanged to some degree with more isotopically normal material during incorporation into the warm protosolar nebula, parent body processing, delivery, recovery, and analysis. Third, ion-molecule reactions represent only one of at least four processes that can produce strong D-H fractionation in the ISM.

  19. Carriers mobility of InAs- and InP- rich InAs-InP solid solutions irradiated by fast neutrons

    SciTech Connect

    Khutsishvili, Elza; Khomasuridze, David; Gabrichidze, Leonti; Kvirkvelia, Bella; Kekelidze, David; Guguchia, Zurab; Aliyev, Vugar; Kekelidze, Nodar

    2013-12-04

    We have studied the low temperature charge carriers mobility in bulk single crystals of InAs- and InP- rich InAs-InP solid solutions irradiated with maximum integral flux 2⋅10{sup 18} n/cm{sup 2} of fast neutrons. Influence of minor component small addition in InAs-InP solid solutions has been revealed. There are also presented data of radiation defects thermal stability.

  20. High e+/e– ratio dense pair creation with 1021W.cm–2 laser irradiating solid targets

    DOE PAGES

    Liang, E.; Clarke, T.; Henderson, A.; ...

    2015-09-14

    In this study, we report results of new pair creation experiments using ~100 Joule pulses of the Texas Petawatt Laser to irradiate solid gold and platinum targets, with intensities up to ~1.9 × 1021 W.cm–2 and pulse durations as short as ~130 fs. Positron to electron (e+/e–) ratios >15% were observed for many thick disk and rod targets, with the highest e+/e– ratio reaching ~50% for a Pt rod. The inferred pair yield was ~ few ×1010 with emerging pair density reaching ~1015/cm3 so that the pair skin depth becomes < pair jet transverse size. These results represent major milestonesmore » towards the goal of creating a significant quantity of dense pair-dominated plasmas with e+/e– approaching 100% and pair skin depth << pair plasma size, which will have wide-ranging applications to astrophysics and fundamental physics.« less

  1. Rapid scan electron paramagnetic resonance at 1.0 GHz of defect centers in γ-irradiated organic solids.

    PubMed

    Shi, Yilin; Rinard, George A; Quine, Richard W; Eaton, Sandra S; Eaton, Gareth R

    2016-02-01

    The radicals in six (60)Co γ-irradiated solids: malonic acid, glycylglycine, 2,6 di-t-butyl 4-methyl phenol, L-alanine, dimethyl malonic acid, and 2-amino isobutyric acid, were studied by rapid scan electron paramagnetic resonance at L-band (1.04 GHz) using a customized Bruker Elexsys spectrometer and a locally-designed dielectric resonator. Sinusoidal scans with widths up to 18.2 mT were generated with the recently described coil driver and Litz wire coils. Power saturation curves showed that the rapid scan signals saturated at higher powers than did conventional continuous wave signals. The rapid scan data were deconvolved and background subtracted to obtain absorption spectra. For the same data acquisition time the signal-to-noise for the absorption spectra obtained in rapid scans were 23 to 37 times higher than for first-derivative spectra obtained by conventional continuous wave electron paramagnetic resonance.

  2. Rapid scan electron paramagnetic resonance at 1.0 GHz of defect centers in γ-irradiated organic solids

    PubMed Central

    Shi, Yilin; Rinard, George A.; Quine, Richard W.; Eaton, Sandra S.; Eaton, Gareth R.

    2016-01-01

    The radicals in six 60Co γ-irradiated solids: malonic acid, glycylglycine, 2,6 di-t-butyl 4-methyl phenol, L-alanine, dimethyl malonic acid, and 2-amino isobutyric acid, were studied by rapid scan electron paramagnetic resonance at L-band (1.04 GHz) using a customized Bruker Elexsys spectrometer and a locally-designed dielectric resonator. Sinusoidal scans with widths up to 18.2 mT were generated with the recently described coil driver and Litz wire coils. Power saturation curves showed that the rapid scan signals saturated at higher powers than did conventional continuous wave signals. The rapid scan data were deconvolved and background subtracted to obtain absorption spectra. For the same data acquisition time the signal-to-noise for the absorption spectra obtained in rapid scans were 23 to 37 times higher than for first-derivative spectra obtained by conventional continuous wave electron paramagnetic resonance. PMID:26834505

  3. The effect of injected interstitials on void formation in self-ion irradiated nickel containing concentrated solid solution alloys

    NASA Astrophysics Data System (ADS)

    Yang, Tai-ni; Lu, Chenyang; Jin, Ke; Crespillo, Miguel L.; Zhang, Yanwen; Bei, Hongbin; Wang, Lumin

    2017-05-01

    Pure nickel and three nickel containing single-phase concentrated solid solution alloys (SP-CSAs) have been irradiated using 3 MeV Ni2+ ions at 500 °C to fluences of 1.5 ×1016 and 5.0 ×1016 cm-2 . The radiation-induced voids were characterized using cross sectional transmission electron microscopy that distributions of voids and dislocation loops were presented as a function of depth. A various degree of void suppression was observed on the tested samples and a defect clusters migration mechanism was proposed for NiCo. In order to sufficiently understand the defect dynamics in these SP-CSAs, the injected interstitial effect has been taken into account along with the 1-dimentional (1-D) and 3-dimentional (3-D) interstitial movement mechanisms.

  4. The effect of injected interstitials on void formation in self-ion irradiated nickel containing concentrated solid solution alloys

    DOE PAGES

    Yang, Tai-ni; Lu, Chenyang; Jin, Ke; ...

    2017-02-21

    Pure nickel and three nickel containing single-phase concentrated solid solution alloys (SP-CSAs) have been irradiated using 3 MeV Ni2+ ions at 500 C to fluences of 1.5 x 1016 and 5.0 x 1016 cm2. We characterized the radiation-induced voids using cross sectional transmission electron microscopy that distributions of voids and dislocation loops were presented as a function of depth. We also observed a various degree of void suppression on the tested samples and a defect clusters migration mechanism was proposed for NiCo. Furthermore, in order to sufficiently understand the defect dynamics in these SP-CSAs, the injected interstitial effect has beenmore » taken into account along with the 1-dimentional (1-D) and 3-dimentional (3-D) interstitial movement mechanisms.« less

  5. EPR study of free radicals in some drugs γ-irradiated in the solid state

    NASA Astrophysics Data System (ADS)

    Ambroż, H. B.; Kornacka, E. M.; Marciniec, B.; Ogrodowczyk, M.; Przybytniak, G. K.

    2000-06-01

    A range of drugs in the form of microcrystalline powder was exposed to γ-radiation. EPR measurements proved that all of them contained various paramagnetic species after 4 and 8 weeks of storage. We observed following radical concentrations, stable up to 4 weeks: the highest for ifosfamide — 4.5×10 17 spins per gram and the lowest for nimodipine — 2.1×10 16 spins per gram. Three drugs exhibited very weak EPR signals before irradiation, not detectable quantitatively. Some spectroscopic properties and suggestions concerning possible structure of the radicals are given in our paper.

  6. LABORATORY STUDIES ON THE IRRADIATION OF SOLID ETHANE ANALOG ICES AND IMPLICATIONS TO TITAN'S CHEMISTRY

    SciTech Connect

    Kim, Y. S.; Bennett, C. J.; Chen, L-H; Kaiser, R. I.; O'Brien, K.

    2010-03-10

    Pure ethane ices (C{sub 2}H{sub 6}) were irradiated at 10, 30, and 50 K under contamination-free, ultrahigh vacuum conditions with energetic electrons generated in the track of galactic cosmic-ray (GCR) particles to simulate the interaction of GCRs with ethane ices in the outer solar system. The chemical processing of the samples was monitored by a Fourier transform infrared spectrometer and a quadrupole mass spectrometer during the irradiation phase and subsequent warm-up phases on line and in situ in order to extract qualitative (products) and quantitative (rate constants and yields) information on the newly synthesized molecules. Six hydrocarbons, methane (CH{sub 4}), acetylene (C{sub 2}H{sub 2}), ethylene (C{sub 2}H{sub 4}), and the ethyl radical (C{sub 2}H{sub 5}), together with n-butane (C{sub 4}H{sub 10}) and butene (C{sub 4}H{sub 8}), were found to form at the radiation dose reaching 1.4 eV per molecule. The column densities of these species were quantified in the irradiated ices at each temperature, permitting us to elucidate the temperature and phase-dependent production rates of individual molecules. A kinetic reaction scheme was developed to fit column densities of those species produced during irradiation of amorphous/crystalline ethane held at 10, 30, or 50 K. In general, the yield of the newly formed molecules dropped consistently for all species as the temperature was raised from 10 K to 50 K. Second, the yield in the amorphous samples was found to be systematically higher than in the crystalline samples at constant temperature. A closer look at the branching ratios indicates that ethane decomposes predominantly to ethylene and molecular hydrogen, which may compete with the formation of n-butane inside the ethane matrix. Among the higher molecular products, n-butane dominates. Of particular relevance to the atmosphere of Saturn's moon Titan is the radiation-induced methane production from ethane-an alternative source of replenishing methane into the

  7. Heating and temperature gradients of lipid bilayer samples induced by RF irradiation in MAS solid-state NMR experiments.

    PubMed

    Wang, Jing; Zhang, Zhengfeng; Zhao, Weijing; Wang, Liying; Yang, Jun

    2016-05-09

    The MAS solid-state NMR has been a powerful technique for studying membrane proteins within the native-like lipid bilayer environment. In general, RF irradiation in MAS NMR experiments can heat and potentially destroy expensive membrane protein samples. However, under practical MAS NMR experimental conditions, detailed characterization of RF heating effect of lipid bilayer samples is still lacking. Herein, using (1) H chemical shift of water for temperature calibration, we systematically study the dependence of RF heating on hydration levels and salt concentrations of three lipids in MAS NMR experiments. Under practical (1) H decoupling conditions used in biological MAS NMR experiments, three lipids show different dependence of RF heating on hydration levels as well as salt concentrations, which are closely associated with the properties of lipids. The maximum temperature elevation of about 10 °C is similar for the three lipids containing 200% hydration, which is much lower than that in static solid-state NMR experiments. The RF heating due to salt is observed to be less than that due to hydration, with a maximum temperature elevation of less than 4 °C in the hydrated samples containing 120 mmol l(-1) of salt. Upon RF irradiation, the temperature gradient across the sample is observed to be greatly increased up to 20 °C, as demonstrated by the remarkable broadening of (1) H signal of water. Based on detailed characterization of RF heating effect, we demonstrate that RF heating and temperature gradient can be significantly reduced by decreasing the hydration levels of lipid bilayer samples from 200% to 30%. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Combined effects of nuclear and electronic energy losses in solids irradiated with a dual-ion beam

    SciTech Connect

    Thome, Lionel; Debelle, Aurelien; Garrido, Frederico; Trocellier, Patrick; Serruys, Yves; Miro, Sandrine

    2013-04-08

    Single and dual-beam irradiations of oxide (c-ZrO{sub 2}, MgO, Gd{sub 2}Ti{sub 2}O{sub 7}) and carbide (SiC) single crystals were performed to study combined effects of nuclear (S{sub n}) and electronic (S{sub e}) energy losses. Rutherford backscattering experiments in channeling conditions show that the S{sub n}/S{sub e} cooperation induces a strong decrease of the irradiation-induced damage in SiC and MgO and almost no effects in c-ZrO{sub 2} and Gd{sub 2}Ti{sub 2}O{sub 7}. The healing process is ascribed to electronic excitations arising from the electronic energy loss of swift ions. These results present a strong interest for both fundamental understanding of the ion-solid interactions and technological applications in the nuclear industry where expected cooperative S{sub n}/S{sub e} effects may lead to the preservation of the integrity of nuclear devices.

  9. Enhancement of photocatalytic activity of zinc-germanium oxynitride solid solution for overall water splitting under visible irradiation.

    PubMed

    Takanabe, Kazuhiro; Uzawa, Tsutomu; Wang, Xinchen; Maeda, Kazuhiko; Katayama, Masao; Kubota, Jun; Kudo, Akihiko; Domen, Kazunari

    2009-12-07

    Overall water splitting to form hydrogen and oxygen over a heterogeneous photocatalyst using solar energy is a promising process for clean and renewable hydrogen production on a large-scale. The ZnGeN2-ZnO solid solution photocatalyst shows photocatalytic activity under visible irradiation. This paper deals with results of photocatalytic reactions over the (Zn(1+x)Ge)(N2O(x)) photocatalyst for overall water splitting. The photocatalyst shows high rates for overall water splitting under visible irradiation, with notable deactivation with time. This study focuses on measuring rates for H2 and O2 evolution to elucidate the cause of the deactivation. Our results showed negligible changes in the structure and the composition of the photocatalyst after the photocatalytic reaction, and thus the changes undetectable by the techniques employed should be the cause of deactivation. This paper also discusses two strategies to improve the photocatalytic activity: metal doping in the oxynitride formulation and post-calcination after nitridation. Several characterization carried out in this study led us to conclude, at the current point, that the improvement of photocatalytic activity is ascribed to the reduction in the number of defects in the photocatalyst materials.

  10. Thorium silicate compound as a solid-state target for production of isomeric thorium-229 nuclei by electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Borisyuk, P. V.; Vasilyev, O. S.; Lebedinskii, Y. Y.; Krasavin, A. V.; Tkalya, E. V.; Troyan, V. I.; Habibulina, R. F.; Chubunova, E. V.; Yakovlev, V. P.

    2016-09-01

    In this paper, we discuss an idea of the experiment for excitation of the isomeric transition in thorium-229 nuclei by irradiating with electron beam targets with necessary physical characteristics. The chemical composition and bandgap of ThSi10O22 were determined by X-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. It was found that the energy gap is equal to 7.7 eV and does not change when the target is exposed to a medium energy electron beam for a long time. This indicates that the compound possesses high electron-beam resistance. A quantitative estimation of the output function of isomeric thorium-229 nuclei generated by interaction of nuclei with the secondary electron flow formed by irradiating the solid-state ThSi10O22-based target is given. The estimation shows that ThSi10O22 is a promising thorium-containing target for investigating excitation of the nuclear low-lying isomeric transition in the thorium-229 isotope using medium-energy electrons.

  11. The study of ultrasonic irradiation effects on solid state powders of HTc superconductor YBa2Cu3O7-x

    NASA Astrophysics Data System (ADS)

    Kargar, Mahboubeh; Khoshnevisan, Bahram

    2016-03-01

    In this paper, an ultrasound assisted solid state synthesis method for high-temperature (HTc) YBa2Cu3O7-x (YBCO) superconductor nanostructures with different morphologies is presented. Here, the routine heat treatment of the powder mixture of as-prepared precursors is followed by the ultrasound irradiation inside various alcoholic solutions. Not only the influence of the ultrasound irradiation intensity and duration but also the influence of different solvents such as ethanol, methanol and 1-butanol with various vapor pressures and so various destruction powers were also studied on the morphology and particle size of the products. The various morphologies were studied by scanning electron microscope (SEM) which not only have been affected by intensity and type of alcoholic solvent but also sonication time and ultrasound power have significant role as well. Formation of the YBCO superconducting phase was examined by using Rietveld refinement of X-ray diffraction (XRD) which indicates the crystalline preferred growth in c-axis orientation in crystal. Magnetic susceptibility measurements showed the ultrasound waves had no important effect on the onset critical temperature of the prepared nanorods (about 91.64 K) which is compared with the bulk samples (Tc ˜ 92K).

  12. Effects of Fe concentration on the ion-irradiation induced defect evolution and hardening in Ni-Fe solid solution alloys

    DOE PAGES

    Jin, Ke; Guo, Wei; Lu, Chenyang; ...

    2016-12-01

    Understanding alloying effects on the irradiation response of structural materials is pivotal in nuclear engineering. In order to systematically explore the effects of Fe concentration on the irradiation-induced defect evolution and hardening in face-centered cubic Ni-Fe binary solid solution alloys, single crystalline Ni-xFe (x = 0–60 at%) alloys have been grown and irradiated with 1.5 MeV Ni ions. The irradiations have been performed over a wide range of fluences from 3 × 1013 to 3 × 1016 cm-2 at room temperature. Ion channeling technique has shown reduced damage accumulation with increasing Fe concentration in the low fluence regime, which ismore » consistent to the results from molecular dynamic simulations. We did not observe any irradiation-induced compositional segregation in atom probe tomography within the detection limit, even in the samples irradiated with high fluence Ni ions. Transmission electron microscopy analyses have further demonstrated that the defect size significantly decreases with increasing Fe concentration, indicating a delay in defect evolution. Furthermore, irradiation induced hardening has been measured by nanoindentation tests. Ni and the Ni-Fe alloys have largely different initial hardness, but they all follow a similar trend for the increase of hardness as a function of irradiation fluence.« less

  13. Effects of Fe concentration on the ion-irradiation induced defect evolution and hardening in Ni-Fe solid solution alloys

    SciTech Connect

    Jin, Ke; Guo, Wei; Lu, Chenyang; Ullah, Mohammad W.; Zhang, Yanwen; Weber, William J.; Wang, Lumin; Poplawsky, Jonathan D.; Bei, Hongbin

    2016-12-01

    Understanding alloying effects on the irradiation response of structural materials is pivotal in nuclear engineering. In order to systematically explore the effects of Fe concentration on the irradiation-induced defect evolution and hardening in face-centered cubic Ni-Fe binary solid solution alloys, single crystalline Ni-xFe (x = 0–60 at%) alloys have been grown and irradiated with 1.5 MeV Ni ions. The irradiations have been performed over a wide range of fluences from 3 × 1013 to 3 × 1016 cm-2 at room temperature. Ion channeling technique has shown reduced damage accumulation with increasing Fe concentration in the low fluence regime, which is consistent to the results from molecular dynamic simulations. We did not observe any irradiation-induced compositional segregation in atom probe tomography within the detection limit, even in the samples irradiated with high fluence Ni ions. Transmission electron microscopy analyses have further demonstrated that the defect size significantly decreases with increasing Fe concentration, indicating a delay in defect evolution. Furthermore, irradiation induced hardening has been measured by nanoindentation tests. Ni and the Ni-Fe alloys have largely different initial hardness, but they all follow a similar trend for the increase of hardness as a function of irradiation fluence.

  14. Interstitial Laser Irradiation of Solid Tumors in Laser Assisted Cancer Immunotherapy

    NASA Astrophysics Data System (ADS)

    Evans, Lindsay; Bandyopadhyay, Pradip

    2006-03-01

    Laser Assisted Cancer Immunotherapy (LACI) is an experimental therapeutic approach in cancer treatment. Current experiments in our laboratory begin with growing superficial tumors 5 to 7 mm in diameter in BALB/C mice using the CRL-2539 cell line. Tumor sizes were measured with a vernier caliper prior to injection of light absorbing dye (Indocyanine Green, ICG) and immunoadjuvant (Glycated Chitosan, GC). These measurements were continued during the post-therapy period. After injection with the ICG and GC, the mice underwent interstitial irradiation of the tumor with a diode laser operating at 804 nm. Microthermocouples were inserted into the tumor and the laser power was varied in order to monitor the temperature and keep it within in the desired range. Tumors were irradiated at 55^o C, 65^oC, and 75^oC to find out at which temperature the maximum amount of tumor necrosis and strong immune response could be elicited. The growth of the tumors after the LACI treatment will be plotted to show the affect of the therapy at different temperatures. The data suggest that the growth rate of the tumors is slowed down considerably using this approach. * This work is supported by a grant from The National Institutes of Health.

  15. Kinetics of the radiation-induced radicals in gamma irradiated solid cefazolin sodium

    NASA Astrophysics Data System (ADS)

    Yurus, S.; Korkmaz, M.

    2005-01-01

    Room and high temperature kinetic and spectroscopic features of the radical species produced in gamma irradiated cefazolin sodium (here after CS) were investigated in detail using electron spin resonance (ESR) spectroscopy to determine the feasibility of its sterilization by radiation and to explore the dosimetric properties of this semi-synthetic representative of cephalosporins. Irradiated CS exhibits an unresolved ESR doublet as other cephalosporins reported up to date. Signal intensity data derived from microwave saturation, dose-response, decays at room and at high temperature studies were analysed assuming a model of two radical species giving rise to doublet and singlet ESR signals. Spectroscopic parameters of these species were determined through spectrum simulation calculations. Decay parameters calculated from annealing studies at seven different temperatures were used to calculate the activation energies of the contributing species. Radiosensitivity of CS to gamma rays was found to be relatively low in the dose range of 0-25 kGy. This conclusion was considered as an indication of the feasibility of radiosterilization of CS by gamma radiation. Five different functions were tried to explore dose-response data of CS in the dose range of 0-25 kGy and it was concluded that a function comprising a linear and a quadratic terms of applied dose describes best experimental results.

  16. Measurements of the energy spectrum of electrons emanating from solid materials irradiated by a picosecond laser

    SciTech Connect

    Di Stefano, C. A.; Kuranz, C. C.; Seely, J. F.; Thomas, A. G. R.; Drake, R. P.; Keiter, P. A.; Williams, G. J.; Park, J.; Chen, H.; MacDonald, M. J.; Rasmus, A. M.; Wan, W. C.; Pereira, N. R.; Joglekar, A. S.; McKelvey, A.; Zhao, Z.; Klein, S. R.; Kemp, G. E.; Jarrott, L. C.; Krauland, C. M.; Peebles, J.; Westover, B.

    2015-04-01

    Here, we present the results of experiments observing the properties of the electron stream generated laterally when a laser irradiates a metal. We also found that the directionality of the electrons is dependent upon their energies, with the higher-energy tail of the spectrum ( 1MeV and higher) being more narrowly focused. This behavior is likely due to the coupling of the electrons to the electric field of the laser. We performed these experiments by using the Titan laser to irradiate a metal wire, creating the electron stream of interest. These electrons propagate to nearby spectator wires of differing metals, causing them to fluoresce at their characteristic K-shell energies. This fluorescence is recorded by a crystal spectrometer. By varying the distances between the wires, we are able to probe the divergence of the electron stream, while by varying the medium through which the electrons propagate (and hence the energy-dependence of electron attenuation), we are able to probe the energy spectrum of the stream.

  17. Measurements of the energy spectrum of electrons emanating from solid materials irradiated by a picosecond laser

    DOE PAGES

    Di Stefano, C. A.; Kuranz, C. C.; Seely, J. F.; ...

    2015-04-01

    Here, we present the results of experiments observing the properties of the electron stream generated laterally when a laser irradiates a metal. We also found that the directionality of the electrons is dependent upon their energies, with the higher-energy tail of the spectrum ( 1MeV and higher) being more narrowly focused. This behavior is likely due to the coupling of the electrons to the electric field of the laser. We performed these experiments by using the Titan laser to irradiate a metal wire, creating the electron stream of interest. These electrons propagate to nearby spectator wires of differing metals, causingmore » them to fluoresce at their characteristic K-shell energies. This fluorescence is recorded by a crystal spectrometer. By varying the distances between the wires, we are able to probe the divergence of the electron stream, while by varying the medium through which the electrons propagate (and hence the energy-dependence of electron attenuation), we are able to probe the energy spectrum of the stream.« less

  18. Theory of the fracture of solid bodies by irradiation with intense pulsed electron beams

    NASA Astrophysics Data System (ADS)

    Borzykh, A. A.; Cherepanov, G. P.

    1980-12-01

    The beam-induced fracture phenomenon consists of the formation of electron bunches in the solid body which act as 'knives' or 'wedges' cutting the body. The basic model problems of the pulsed electron fracture of solid materials are reviewed. Attention is given to the collective relativistic interaction of electron beams with materials; a mechanism of self-densification of electron beams is discussed. An exact solution is obtained for the plane stationary dynamic problem of elasticity for the supersonic motion of an infinite thin wedge. This solution is used to study the deceleration of a finite wedge in the quasi-steady approximation; a simple evaluation of the dimensions of fracture is obtained for large initial velocity of the wedge.

  19. Chemical effects induced by gamma-irradiation in solid and in aqueous methanol solutions of 4-iodophenol

    NASA Astrophysics Data System (ADS)

    Mahfouz, R. M.; Siddiqui, M. R. H.; Al-Wassil, A. I.; Al-Resayes, S. I.; Al-Otaibi, A. M.

    2005-05-01

    The present work is a study on radiolyses of 4-iodophenol in aqueous methanol solutions. The radiolysis products are separated and identified using spectrophotometric and chromatographic techniques. The radiolytic products (I-2, I- and IO3-) formed in aerated solutions at room temperature were identified and the yields are investigated as a function of absorbed gamma-ray dose. The formation of I-2 is mainly dependent on the acidity of solution and produced via the pathway of secondary free radical reactions. Aromatic products of lower and higher molecular weight than the corresponding investigated compound were analysed and separated by HPLC. The results have been discussed in view of mechanisms based on free radicals and ion-molecule interactions. The chemical effects induced by gamma-irradiation in solid 4-iodophenol have also been investigated and the degradation products were identified in solid state by NMR, GC/MS experiments and HPLC after dissolution in aqueous methanol. The results were evaluated and compared with radiolysis data.

  20. Laser light-stimulated exoelectron emission from solid Ar pre-irradiated by an electron beam

    NASA Astrophysics Data System (ADS)

    Gumenchuk, G. B.; Belov, A. G.; Savchenko, E. V.; Ponomaryov, A. N.; Bondybey, V. E.

    2007-06-01

    Spatially separated stable charge centers, self-trapped holes and trapped electrons, were generated in Ar cryocrystals by a low-energy electron beam. A combination of the cathodoluminescence (CL) and photon-stimulated exoelectron emission (PSEE) methods was used to monitor center formation and a selected relaxation channel—exoelectron emission. It was found that photon-promoted electron current decreased exponentially under irradiation with the laser operating in the visible range. The influence of the laser parameters (power and wavelength) on the characteristic lifetime of exoelectron emission is discussed. Effective bleaching of the low-temperature peaks of thermally stimulated exoelectron emission by the laser light in a visible range is observed.

  1. Stress-induced solid flow drives surface nanopatterning of silicon by ion-beam irradiation

    NASA Astrophysics Data System (ADS)

    Castro, M.; Gago, R.; Vázquez, L.; Muñoz-García, J.; Cuerno, R.

    2012-12-01

    Ion-beam sputtering (IBS) is known to produce surface nanopatterns over macroscopic areas on a wide range of materials. However, in spite of the technological potential of this route to nanostructuring, the physical process by which these surfaces self-organize remains poorly understood. We have performed detailed experiments of IBS on Si substrates that validate dynamical and morphological predictions from a hydrodynamic description of the phenomenon. We introduce a systematic approach to perform the experiments under conditions that guarantee the applicability of a linear description, helping to clarify the experimental framework in which theories should be tested. Among our results, the pattern wavelength is experimentally seen to depend almost linearly on ion energy, in agreement with existing results for other targets that are amorphous or become so under irradiation. Our work substantiates flow of a nanoscopically thin and highly viscous surface layer, driven by the stress created by the ion beam, as an accurate description of this class of systems.

  2. Solid organic residues produced by irradiation of hydrocarbon-containing H2O and H2O/NH3 ices - Infrared spectroscopy and astronomical implications

    NASA Technical Reports Server (NTRS)

    Khare, B. N.; Thompson, W. R.; Murray, B. G. J. P. T.; Chyba, C. F.; Sagan, C.

    1989-01-01

    Plasma-discharge irradiations were conducted for the methane clathrate expected in outer solar system satellites and cometary nuclei; also irradiated were ices prepared from other combinations of H2O with CH4, C2H6, or C2H2. Upon evaporation of the yellowish-to-tan irradiated ices, it is found that a colored solid film adheres to the walls of the reaction vessel at room temperature. These organic films are found to exhibit IR band identifiable with alkane, aldehide, alcohol, and perhaps alkene, as well as substituted aromatic functional groups. These spectra are compared with previous studies of UV- or photon-irradiated nonclathrated hydrocarbon-containing ices.

  3. Solid organic residues produced by irradiation of hydrocarbon-containing H2O and H2O/NH3 ices - Infrared spectroscopy and astronomical implications

    NASA Astrophysics Data System (ADS)

    Khare, B. N.; Thompson, W. R.; Murray, B. G. J. P. T.; Chyba, C. F.; Sagan, C.; Arakawa, E. T.

    1989-06-01

    Plasma-discharge irradiations were conducted for the methane clathrate expected in outer solar system satellites and cometary nuclei; also irradiated were ices prepared from other combinations of H2O with CH4, C2H6, or C2H2. Upon evaporation of the yellowish-to-tan irradiated ices, it is found that a colored solid film adheres to the walls of the reaction vessel at room temperature. These organic films are found to exhibit IR band identifiable with alkane, aldehide, alcohol, and perhaps alkene, as well as substituted aromatic functional groups. These spectra are compared with previous studies of UV- or photon-irradiated nonclathrated hydrocarbon-containing ices.

  4. Separation of actinides from irradiated An-Zr based fuel by electrorefining on solid aluminium cathodes in molten LiCl-KCl

    NASA Astrophysics Data System (ADS)

    Souček, P.; Murakami, T.; Claux, B.; Meier, R.; Malmbeck, R.; Tsukada, T.; Glatz, J.-P.

    2015-04-01

    An electrorefining process for metallic spent nuclear fuel treatment is being investigated in ITU. Solid aluminium cathodes are used for homogeneous recovery of all actinides within the process carried out in molten LiCl-KCl eutectic salt at a temperature of 500 °C. As the selectivity, efficiency and performance of solid Al has been already shown using un-irradiated An-Zr alloy based test fuels, the present work was focused on laboratory-scale demonstration of the process using irradiated METAPHIX-1 fuel composed of U67-Pu19-Zr10-MA2-RE2 (wt.%, MA = Np, Am, Cm, RE = Nd, Ce, Gd, Y). Different electrorefining techniques, conditions and cathode geometries were used during the experiment yielding evaluation of separation factors, kinetic parameters of actinide-aluminium alloy formation, process efficiency and macro-structure characterisation of the deposits. The results confirmed an excellent separation and very high efficiency of the electrorefining process using solid Al cathodes.

  5. Generation of higher-order harmonics from solid targets irradiated with fs-laser pulses

    NASA Astrophysics Data System (ADS)

    Tsakiris, G. D.

    1998-11-01

    The prospect of laser intensities exceeding the 10^19 W/cm^2 level becoming available from table-top, 10 Hz lasers, has given new impetus to the subject of solid harmonics [1]. After the initial experiments demonstrating the feasibility of harmonic generation with fs-laser pulses [2], the current effort is directed towards finding out the link between relevant plasma parameters and harmonic generation. The questions that arise are what are the limitations inherent to the generation mechanism and how one can optimize the harmonic yield. For example, in experiments using the Ti:sapphire laser ATLAS at Max-Planck Institut für Quantenoptik [3], it was found that the lower the contrast of the laser pulse the weaker the Iλ^2 scaling of the harmonic conversion efficiency. Some of these results are presented and their implications to solid harmonic generation at higher intensities will be discussed. [1] P. Gibbon, IEEE J. of Q. Elec. 33, 1915 (1997). [2] S. Kohlweyer, et al., Optics Comm. 177, 431 (1995). [3] M. Zepf, et al., submitted for publication in Phys. Rev. Lett.

  6. Fundamental aspects of deuterium retention in tungsten at high flux plasma exposure

    SciTech Connect

    Ogorodnikova, O. V.

    2015-08-21

    An effect of enhanced trapping of deuterium in tungsten at high flux was discovered. It was shown analytically and confirmed experimentally that the deuterium trapping in a presence of high density of defects in tungsten (W) depends on the ion energy and ion flux. Newly developed analytical model explains experimentally observed discrepancy of deuterium trapping at radiation-induced defects in tungsten at different ion fluxes that significantly improves a prediction of hydrogen isotope accumulation in different plasma devices, including ITER and DEMO. The developed model can be used for many system of hydrogen in a metal in both normal and extreme environments (high fluxes, elevated temperatures, neutron irradiation, etc.). This new model allows, for the first time, to validate density function theory (DFT) predictions of multiple occupation of a defect with deuterium against experimental data that bridge the gap in length and time scale between DFT calculations and experiments. By comparing first-principle calculations based on DFT and semi-empirical “adsorption model,” it was proved that the mechanism of hydrogen isotope trapping in a vacancy cluster is similar to a chemisorption on a surface. Binding energies of deuterium with different types of defects in W were defined. Moreover, the surface barrier of deuterium to be chemisorbed on a clean W surface was found to be less than 1 eV and kinetics of deuterium release is limited by de-trapping from defects rather than to be limited by surface effects.

  7. Fundamental aspects of deuterium retention in tungsten at high flux plasma exposure

    NASA Astrophysics Data System (ADS)

    Ogorodnikova, O. V.

    2015-08-01

    An effect of enhanced trapping of deuterium in tungsten at high flux was discovered. It was shown analytically and confirmed experimentally that the deuterium trapping in a presence of high density of defects in tungsten (W) depends on the ion energy and ion flux. Newly developed analytical model explains experimentally observed discrepancy of deuterium trapping at radiation-induced defects in tungsten at different ion fluxes that significantly improves a prediction of hydrogen isotope accumulation in different plasma devices, including ITER and DEMO. The developed model can be used for many system of hydrogen in a metal in both normal and extreme environments (high fluxes, elevated temperatures, neutron irradiation, etc.). This new model allows, for the first time, to validate density function theory (DFT) predictions of multiple occupation of a defect with deuterium against experimental data that bridge the gap in length and time scale between DFT calculations and experiments. By comparing first-principle calculations based on DFT and semi-empirical "adsorption model," it was proved that the mechanism of hydrogen isotope trapping in a vacancy cluster is similar to a chemisorption on a surface. Binding energies of deuterium with different types of defects in W were defined. Moreover, the surface barrier of deuterium to be chemisorbed on a clean W surface was found to be less than 1 eV and kinetics of deuterium release is limited by de-trapping from defects rather than to be limited by surface effects.

  8. Ignition of deuterium-trtium fuel targets

    DOEpatents

    Musinski, Donald L.; Mruzek, Michael T.

    1991-01-01

    A method of igniting a deuterium-tritium ICF fuel target to obtain fuel burn in which the fuel target initially includes a hollow spherical shell having a frozen layer of DT material at substantially uniform thickness and cryogenic temperature around the interior surface of the shell. The target is permitted to free-fall through a target chamber having walls heated by successive target ignitions, so that the target is uniformly heated during free-fall to at least partially melt the frozen fuel layer and form a liquid single-phase layer or a mixed liquid/solid bi-phase layer of substantially uniform thickness around the interior shell surface. The falling target is then illuminated from exteriorly of the chamber while the fuel layer is at substantially uniformly single or bi-phase so as to ignite the fuel layer and release energy therefrom.

  9. Ignition of deuterium-tritium fuel targets

    DOEpatents

    Musinski, D.L.; Mruzek, M.T.

    1991-08-27

    Disclosed is a method of igniting a deuterium-tritium ICF fuel target to obtain fuel burn in which the fuel target initially includes a hollow spherical shell having a frozen layer of DT material at substantially uniform thickness and cryogenic temperature around the interior surface of the shell. The target is permitted to free-fall through a target chamber having walls heated by successive target ignitions, so that the target is uniformly heated during free-fall to at least partially melt the frozen fuel layer and form a liquid single-phase layer or a mixed liquid/solid bi-phase layer of substantially uniform thickness around the interior shell surface. The falling target is then illuminated from exteriorly of the chamber while the fuel layer is at substantially uniformly single or bi-phase so as to ignite the fuel layer and release energy therefrom. 5 figures.

  10. Deuterium pellet injector gun design

    SciTech Connect

    Lunsford, R.V.; Wysor, R.B.; Bryan, W.E.; Shipley, W.D.; Combs, S.K.; Foust, C.R.; Milora, S.L.; Fisher, P.W.

    1985-01-01

    The Deuterium Pellet Injector (DPI), an eight-pellet pneumatic injector, is being designed and fabricated for the Tokamak Fusion Test Reactor (TFTR). It will accelerate eight pellets, 4 by 4 mm maximum, to greater than 1500 m/s. It utilizes a unique pellet-forming mechanism, a cooled pellet storage wheel, and improved propellant gas scavenging.

  11. Electron spin-lattice relaxation in radicals containing two methyl groups, generated by /γ-irradiation of polycrystalline solids

    NASA Astrophysics Data System (ADS)

    Harbridge, James R.; Eaton, Sandra S.; Eaton, Gareth R.

    2002-12-01

    The effects of methyl rotation on electron spin-lattice relaxation times were examined by pulsed electron paramagnetic resonance for the major radicals in γ-irradiated polycrystalline α-amino isobutyric acid, dimethyl-malonic acid, and L-valine. The dominant radical is the same in irradiated dimethyl-malonic acid and α-amino isobutyric acid. Continuous wave saturation recovery was measured between 10 and 295 K at S-band and X-band. Inversion recovery, echo-detected saturation recovery, and pulsed electron-electron double resonance (ELDOR) data were obtained between 77 and 295 K. For the radicals in the three solids, recovery time constants measured by the various techniques were not the same, because spectral diffusion processes contribute differently for each measurement. Hyperfine splitting due to the protons of two methyl groups is resolved in the EPR spectra for each of the samples. Pulsed ELDOR data were obtained to characterize the spectral diffusion processes that transfer magnetization between hyperfine lines. Time constants were obtained for electron spin-lattice relaxation ( T1e), nuclear spin relaxation ( T1n), cross-relaxation ( Tx1), and spin diffusion ( Ts). Between 77 and 295 K rapid cross-relaxation (Δ Ms=±1, Δ MI=∓1) was observed for each sample, which is attributed to methyl rotation at a rate that is approximately equal to the electron Larmor frequency. The large temperature range over which cross-relaxation was observed suggests that methyl groups in the radical and in the lattice, with different activation energies for rotation, contribute to the rapid cross-relaxation. Activation energies for methyl and amino group rotation between 160 and 1900 K (1.3-16 kJ/mol) were obtained by analysis of the temperature dependence of 1/ T1e at S-band and X-band in the temperature intervals where the dynamic process dominates T1e.

  12. Factors affecting total dissolved solids concentration of γ-ray-irradiated aqueous hexamethylenetetramine solution: a dosimetric study.

    PubMed

    Sife-Eldeen, Kh A

    2014-12-01

    A new γ-ray-radiation dosimetric system (TDS-HMTA), comprising a 'total dissolved solids (TDS)' meter and 0.02 M aqueous hexamethylenetetramine (HMTA) solution, is introduced for medical and biological applications. Gamma-ray radiolysis of aqueous HTMA solutions increases the concentrations (ppm) of TDS, which is measured by the TDS meter. The effects of HMTA concentration, absorbed radiation dose, absorbed dose rate, and storage time on the TDS concentration of irradiated HMTA solutions were studied. It was found that 0.02 M aqueous HMTA solution yields the highest sensitivity to γ-ray-radiation according to TDS concentration measurements. The effect of absorbed radiation dose was studied in the range 1.64-435.5 kGy. The TDS concentration increases linearly up to the maximum of the studied absorbed radiation dose range (R(2) = 0.9965). The overall coefficient of variation (CV %) associated with TDS concentration measurements of 0.02 M HMTA solution as a function of absorbed dose was found to be 0.732%. The effect of dose rate on the TDS concentration was studied in the range 0.33-3.31 kGy/h. It was found, also, that the TDS concentration is relatively stable over a storage period of 144 h after irradiation with different doses. The tissue equivalency of 0.02 M aqueous HMTA solutions allow it to be used for radiation dose measurement during sterilization in human tissue banks. Therefore, this system (TDS-HMTA) could be considered as a promising candidate for γ-ray radiation dosimetry in technical, medical and research fields.

  13. Equations of state for hydrogen and deuterium.

    SciTech Connect

    Kerley, Gerald Irwin (Kerley Technical Services, Appomattox, VA)

    2003-12-01

    This report describes the complete revision of a deuterium equation of state (EOS) model published in 1972. It uses the same general approach as the 1972 EOS, i.e., the so-called 'chemical model,' but incorporates a number of theoretical advances that have taken place during the past thirty years. Three phases are included: a molecular solid, an atomic solid, and a fluid phase consisting of both molecular and atomic species. Ionization and the insulator-metal transition are also included. The most important improvements are in the liquid perturbation theory, the treatment of molecular vibrations and rotations, and the ionization equilibrium and mixture models. In addition, new experimental data and theoretical calculations are used to calibrate certain model parameters, notably the zero-Kelvin isotherms for the molecular and atomic solids, and the quantum corrections to the liquid phase. The report gives a general overview of the model, followed by detailed discussions of the most important theoretical issues and extensive comparisons with the many experimental data that have been obtained during the last thirty years. Questions about the validity of the chemical model are also considered. Implications for modeling the 'giant planets' are also discussed.

  14. Color-discriminating retinal configurations of sensory rhodopsin I by photo-irradiation solid-state NMR spectroscopy.

    PubMed

    Yomoda, Hiroki; Makino, Yoshiteru; Tomonaga, Yuya; Hidaka, Tetsurou; Kawamura, Izuru; Okitsu, Takashi; Wada, Akimori; Sudo, Yuki; Naito, Akira

    2014-07-01

    SRI (sensory rhodopsin I) can discriminate multiple colors for the attractant and repellent phototaxis. Studies aimed at revealing the color-dependent mechanism show that SRI is a challenging system not only in photobiology but also in photochemistry. During the photoreaction of SRI, an M-intermediate (attractant) transforms into a P-intermediate (repellent) by absorbing blue light. Consequently, SRI then cycles back to the G-state. The photoreactions were monitored with the (13)C NMR signals of [20-(13)C]retnal-SrSRI using in situ photo-irradiation solid-state NMR spectroscopy. The M-intermediate was trapped at -40 °C by illumination at 520 nm. It was transformed into the P-intermediate by subsequent illumination at 365 nm. These results reveal that the G-state could be directly transformed to the P-intermediate by illumination at 365 nm. Thus, the stationary trapped M- and P-intermediates are responsible for positive and negative phototaxis, respectively. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Dual beam experiment for simultaneous irradiation of surfaces with ion species of gaseous and solid-state elements

    NASA Astrophysics Data System (ADS)

    Bizyukov, I.; Krieger, K.

    2006-04-01

    The effects occurring under simultaneous bombardment of surfaces by ions of gaseous and solid elements is a new field for research, which is of great interest for applications ranging from cold plasma technologies to nuclear fusion in magnetically confined plasmas. A multitude of new effects has been observed originating from mixing of incident ion species and bulk material at the surface and, in some cases, from additional complex chemical interactions between the mixing species. To study these effects under controlled conditions a new dual beam experiment has been commissioned, particularly suited for in situ studies of surface sputtering and ion implantation processes. Thin films with negligible impurity level and surface roughness are used as targets. High energy ion beam analysis is used as a means of nondestructive elemental depth profiling and concentration measurements. This allows for the first time the fast quantification of the elemental composition change of a target sample in intervals between ion irradiation. The article describes the details of design and operation, as well as the accessible range of experimental conditions.

  16. Dynamics and structure of self-generated magnetics fields on solids following high contrast, high intensity laser irradiation

    SciTech Connect

    Albertazzi, B.; Chen, S. N.; Fuchs, J.; Antici, P.; Böker, J.; Swantusch, M.; Willi, O.; Borghesi, M.; Breil, J.; Feugeas, J. L.; Nicolaï, Ph.; Tikhonchuk, V. T.; D'Humières, E.; Dervieux, V.; Nakatsutsumi, M.; Romagnagni, L.; Lancia, L.; Shepherd, R.; Sentoku, Y.; Starodubtsev, M.; and others

    2015-12-15

    The dynamics of self-generated magnetic B-fields produced following the interaction of a high contrast, high intensity (I > 10{sup 19 }W cm{sup −2}) laser beam with thin (3 μm thick) solid (Al or Au) targets is investigated experimentally and numerically. Two main sources drive the growth of B-fields on the target surfaces. B-fields are first driven by laser-generated hot electron currents that relax over ∼10–20 ps. Over longer timescales, the hydrodynamic expansion of the bulk of the target into vacuum also generates B-field induced by non-collinear gradients of density and temperature. The laser irradiation of the target front side strongly localizes the energy deposition at the target front, in contrast to the target rear side, which is heated by fast electrons over a much larger area. This induces an asymmetry in the hydrodynamic expansion between the front and rear target surfaces, and consequently the associated B-fields are found strongly asymmetric. The sole long-lasting (>30 ps) B-fields are the ones growing on the target front surface, where they remain of extremely high strength (∼8–10 MG). These B-fields have been recently put by us in practical use for focusing laser-accelerated protons [B. Albertazzi et al., Rev. Sci. Instrum. 86, 043502 (2015)]; here we analyze in detail their dynamics and structure.

  17. Mechanisms of H2O desorption from amorphous solid water by 157-nm irradiation: an experimental and theoretical study.

    PubMed

    DeSimone, Alice J; Crowell, Vernon D; Sherrill, C David; Orlando, Thomas M

    2013-10-28

    The photodesorption of water molecules from amorphous solid water (ASW) by 157-nm irradiation has been examined using resonance-enhanced multiphoton ionization. The rotational temperature has been determined, by comparison with simulations, to be 425 ± 75 K. The time-of-flight spectrum of H2O (v = 0) has been fit with a Maxwell-Boltzmann distribution with a translational temperature of 700 ± 200 K (0.12 ± 0.03 eV). H(+) and OH(+) fragment ions have been detected with non-resonant multiphoton ionization, indicating vibrationally excited parent water molecules with translational energies of 0.24 ± 0.08 eV. The cross section for water removal from ASW by 7.9-eV photons near 100 K is (6.9 ± 1.8) × 10(-20) cm(2) for >10 L H2O exposure. Electronic structure computations have also probed the excited states of water and the mechanisms of desorption. Calculated electron attachment and detachment densities show that exciton delocalization leads to a dipole reversal state in the first singlet excited state of a model system of hexagonal water ice. Ab Initio Molecular Dynamics simulations show possible desorption of a photo-excited water molecule from this cluster, though the non-hydrogen bonded OH bond is stretched significantly before desorption. Potential energy curves of this OH stretch in the electronic excited state show a barrier to dissociation, lending credence to the dipole reversal mechanism.

  18. Mechanisms of H2O desorption from amorphous solid water by 157-nm irradiation: An experimental and theoretical study

    NASA Astrophysics Data System (ADS)

    DeSimone, Alice J.; Crowell, Vernon D.; Sherrill, C. David; Orlando, Thomas M.

    2013-10-01

    The photodesorption of water molecules from amorphous solid water (ASW) by 157-nm irradiation has been examined using resonance-enhanced multiphoton ionization. The rotational temperature has been determined, by comparison with simulations, to be 425 ± 75 K. The time-of-flight spectrum of H2O (v = 0) has been fit with a Maxwell-Boltzmann distribution with a translational temperature of 700 ± 200 K (0.12 ± 0.03 eV). H+ and OH+ fragment ions have been detected with non-resonant multiphoton ionization, indicating vibrationally excited parent water molecules with translational energies of 0.24 ± 0.08 eV. The cross section for water removal from ASW by 7.9-eV photons near 100 K is (6.9 ± 1.8) × 10-20 cm2 for >10 L H2O exposure. Electronic structure computations have also probed the excited states of water and the mechanisms of desorption. Calculated electron attachment and detachment densities show that exciton delocalization leads to a dipole reversal state in the first singlet excited state of a model system of hexagonal water ice. Ab Initio Molecular Dynamics simulations show possible desorption of a photo-excited water molecule from this cluster, though the non-hydrogen bonded OH bond is stretched significantly before desorption. Potential energy curves of this OH stretch in the electronic excited state show a barrier to dissociation, lending credence to the dipole reversal mechanism.

  19. Deuterium-deuterium nuclear reaction induced by high intensity laser pulses

    NASA Astrophysics Data System (ADS)

    Torrisi, L.; Cavallaro, S.; Cutroneo, M.; Giuffrida, L.; Krasa, J.; Margarone, D.; Velyhan, A.; Kravarik, J.; Ullschmied, J.; Wolowski, J.; Szydlowski, A.; Rosinski, M.

    2013-05-01

    A 1016 W/cm2 Asterix laser pulse intensity, 1315 nm wavelength, 300 ps pulse duration, was employed at PALS laboratory of Prague, to irradiate thick and thin primary CD2 targets placed into the high vacuum chamber. The laser irradiation produces non-equilibrium plasma with deuterons and carbon ions emission with energy up to about 4 MeV per charge state, as measured by time-of-flight (TOF) techniques by using ion collectors and silicon carbide detectors. Accelerated deuterium ions may induce high D-D cross section for fusion processes generating 3 MeV protons and 2.5 MeV neutrons, as measured by TOF analyses. In order to increase the mono-energetic proton yield, secondary CD2 targets can be availed to be irradiated by the plasma-accelerated deuterons. Experiments demonstrated that high intensity laser pulses can be employed to promote nuclear reactions from which characteristic ion streams may be developed. Results open new scenario for applications of laser-generated plasma to the fields of ion sources and ion accelerators.

  20. A dosimetry study of deuterium-deuterium neutron generator-based in vivo neutron activation analysis

    NASA Astrophysics Data System (ADS)

    Sowers, Daniel A.

    A neutron irradiation cavity for in vivo Neutron Activation Analysis (IVNAA) to detect manganese, aluminum, and other potentially toxic elements in human hand bone has been designed and its dosimetric specifications measured. The neutron source is a customized deuterium-deuterium neutron generator which produces neutrons at 2.45 MeV by the fusion reaction 2H(d, n)3He at a calculated flux of 7 x 108 +/-30% s-1. A moderator/reflector/shielding (5 cm high density polyethylene (HDPE), 5.3 cm graphite & 5.7 cm borated HDPE) assembly has been designed and built to maximize the thermal neutron flux inside the hand irradiation cavity and to reduce the extremity dose and effective dose to the human subject. Lead sheets are used to attenuate bremsstrahlung x rays and activation gammas. A Monte Carlo simulation (MCNP6) was used to model the system and calculate extremity dose. The extremity dose was measured with neutron and photon sensitive film badges and Fuji electronic pocket dosimeter (EPD). The neutron ambient dose outside the shielding was measured by Fuji NSN3, and photon dose by a Bicron MicroREM scintillator. Neutron extremity dose was calculated to be 32.3 mSv using MCNP6 simulations given a 10 min IVNAA measurement of manganese. Measurements by EPD and film badge indicate hand dose to be 31.7 +/- 0.8 mSv for neutron and 4.2 +/- 0.2 mSv for photon for 10 mins; whole body effective dose was calculated conservatively to be 0.052 mSv. Experimental values closely match values obtained from MCNP6 simulations. These are acceptable doses to apply the technology for a manganese toxicity study in a human population.

  1. A Dosimetry Study of Deuterium-Deuterium Neutron Generator-based In Vivo Neutron Activation Analysis.

    PubMed

    Sowers, Daniel; Liu, Yingzi; Mostafaei, Farshad; Blake, Scott; Nie, Linda H

    2015-12-01

    A neutron irradiation cavity for in vivo neutron activation analysis (IVNAA) to detect manganese, aluminum, and other potentially toxic elements in human hand bone has been designed and its dosimetric specifications measured. The neutron source is a customized deuterium-deuterium neutron generator that produces neutrons at 2.45 MeV by the fusion reaction 2H(d, n)3He at a calculated flux of 7 × 10(8) ± 30% s(-1). A moderator/reflector/shielding [5 cm high density polyethylene (HDPE), 5.3 cm graphite and 5.7 cm borated (HDPE)] assembly has been designed and built to maximize the thermal neutron flux inside the hand irradiation cavity and to reduce the extremity dose and effective dose to the human subject. Lead sheets are used to attenuate bremsstrahlung x rays and activation gammas. A Monte Carlo simulation (MCNP6) was used to model the system and calculate extremity dose. The extremity dose was measured with neutron and photon sensitive film badges and Fuji electronic pocket dosimeters (EPD). The neutron ambient dose outside the shielding was measured by Fuji NSN3, and the photon dose was measured by a Bicron MicroREM scintillator. Neutron extremity dose was calculated to be 32.3 mSv using MCNP6 simulations given a 10-min IVNAA measurement of manganese. Measurements by EPD and film badge indicate hand dose to be 31.7 ± 0.8 mSv for neutrons and 4.2 ± 0.2 mSv for photons for 10 min; whole body effective dose was calculated conservatively to be 0.052 mSv. Experimental values closely match values obtained from MCNP6 simulations. These are acceptable doses to apply the technology for a manganese toxicity study in a human population.

  2. Laser-driven acoustic desorption of organic molecules from back-irradiated solid foils.

    SciTech Connect

    Zinovev, A. V.; Veryovkin, I. V.; Moore, J. F.; Pellin, M. J.; Materials Science Division; Mass Think

    2007-11-01

    Laser-induced acoustic desorption (LIAD) from thin metal foils is a promising technique for gentle and efficient volatilization of intact organic molecules from surfaces of solid substrates. Using the single-photon ionization method combined with time-of-flight mass spectrometry, we have examined the neutral component of the desorbed flux in LIAD and compared it to that from direct laser desorption. These basic studies of LIAD, conducted for molecules of various organic dyes (rhodamine B, fluorescein, anthracene, coumarin, BBQ), have demonstrated detection of intact parent molecules of the analyte even at its surface concentrations corresponding to a submonolayer coating. In some cases (rhodamine B, fluorescein, BBQ), the parent molecular ion peak was accompanied by a few fragmentation peaks of comparable intensity, whereas for others, only peaks corresponding to intact parent molecules were detected. At all measured desorbing laser intensities (from 100 to 500 MW/cm{sup 2}), the total amount of desorbed parent molecules depended exponentially on the laser intensity. Translational velocities of the desorbed intact molecules, determined for the first time in this work, were of the order of hundreds of meters per second, less than what has been observed in our experiments for direct laser desorption, but substantially greater than the possible perpendicular velocity of the substrate foil surface due to laser-generated acoustic waves. Moreover, these velocities did not depend on the desorbing laser intensity, which implies the presence of a more sophisticated mechanism of energy transfer than direct mechanical or thermal coupling between the laser pulse and the adsorbed molecules. Also, the total flux of desorbed intact molecules as a function of the total number of desorbing laser pulses, striking the same point on the target, decayed following a power law rather than an exponential function, as would have been predicted by the shake-off model. To summarize, the

  3. Experimental Simulation of the Radionuclide Behaviour in the Process of Creating Additional Safety Barriers in Solid Radioactive Waste Repositories Containing Irradiated Graphite

    NASA Astrophysics Data System (ADS)

    Pavliuk, A. O.; Kotlyarevskiy, S. G.; Bespala, E. V.; Zakarova, E. V.; Rodygina, N. I.; Ermolaev, V. M.; Proshin, I. M.; Volkova, A.

    2016-08-01

    Results of the experimental modeling of radionuclide behavior when creating additional safety barriers in solid radioactive waste repositories are presented. The experiments were run on the repository mockup containing solid radioactive waste fragments including irradiated graphite. The repository mockup layout is given; the processes with radionuclides that occur during the barrier creation with a clayey solution and during the following barrier operation are investigated. The results obtained confirm high anti-migration and anti-filtration properties of clay used for the barrier creation even under the long-term excessive water saturation of rocks confining the repository.

  4. Influence of displacement damage on deuterium and helium retention in austenitic and ferritic-martensitic alloys considered for ADS service

    NASA Astrophysics Data System (ADS)

    Voyevodin, V. N.; Karpov, S. A.; Kopanets, I. E.; Ruzhytskyi, V. V.; Tolstolutskaya, G. D.; Garner, F. A.

    2016-01-01

    The behavior of ion-implanted hydrogen (deuterium) and helium in austenitic 18Cr10NiTi stainless steel, EI-852 ferritic steel and ferritic/martensitic steel EP-450 and their interaction with displacement damage were investigated. Energetic argon irradiation was used to produce displacement damage and bubble formation to simulate nuclear power environments. The influence of damage morphology and the features of radiation-induced defects on deuterium and helium trapping in structural alloys was studied using ion implantation, the nuclear reaction D(3He,p)4He, thermal desorption spectrometry and transmission electron microscopy. It was found in the case of helium irradiation that various kinds of helium-radiation defect complexes are formed in the implanted layer that lead to a more complicated spectra of thermal desorption. Additional small changes in the helium spectra after irradiation with argon ions to a dose of ≤25 dpa show that the binding energy of helium with these traps is weakly dependent on the displacement damage. It was established that retention of deuterium in ferritic and ferritic-martensitic alloys is three times less than in austenitic steel at damage of ˜1 dpa. The retention of deuterium in steels is strongly enhanced by presence of radiation damages created by argon ion irradiation, with a shift in the hydrogen release temperature interval of 200 K to higher temperature. At elevated temperatures of irradiation the efficiency of deuterium trapping is reduced by two orders of magnitude.

  5. Deuterium implantation in magnetic garnets

    SciTech Connect

    Wilts, C.H.; Urai, A.

    1988-11-01

    The magnetic effects of deuterium implantation and subsequent annealing were measured in Gd, Tm, and Ga-substituted yttrium iron garnet films for comparison with measurements made earlier with hydrogen implantation. Implantation energy was 60 keV and the dose ranged from 0.5 to 3 x 10/sup 16/ ions/cm/sup 2/ for D/sup +//sub 2/ ions, as compared to an energy of 120 keV and a dose from 0.3 to 4 x 10/sup 16/ ions/cm/sup 2/ for H/sup +//sub 2/ in the earlier study. Measurements made included x-ray rocking curves and ferromagnetic resonance spectra measured at 9.5 GHz. For all doses the implanted layer remained crystalline. Implanted layer thickness was about 4200 A and peak strain occured at a depth of 2600 A. Peak strain increased monotonically, but departed from a linear relation with dose. For the highest dose, the peak strain was 2.5%. Relaxation of strain with annealing was intermediate between that found earlier for hydrogen and neon implantation. As compared to all other implant elements, both deuterium and hydrogen show a large anomalous magnetic anisotropy which can exceed 10 000 Oe for either ion. The absence of this effect for He, Ne, and other ions supports the conjecture that the effect is chemical and related to electronic bonding rather than strain or disorder. The anomalous anisotropy for deuterium decreases and shifts location with annealing. It has largely disappeared at temperatures of 300--350 /sup 0/C. The shape of the profile is consistent with the hypothesis that the shift in anisotropy is associated with diffusion of the deuterium atoms to the surface of the garnet film. At the highest dose, crystalline damage in the region of highest strain is sufficient to radically alter magnetic properties and in particular reduces even the excess anisotropy so that a two-peak profile results until modified by annealing.

  6. Deuterium in the daytime thermosphere

    NASA Technical Reports Server (NTRS)

    Breig, E. L.; Sanatani, S.; Hanson, W. B.

    1987-01-01

    Ion concentration measurements for H(+) and D(+) from the magnetic ion mass spectrometer on the Atmosphere Explorer C satellite are used, in conjunction with other atmospheric data, to determine the concentrations of H and D in the nonpolar daytime thermosphere. The ratio of the observed D(+) to H(+) concentrations has essentially the same height dependence in the 300 to 800-km region as expected for their neutral counterparts, even in the presence of ion temperature gradients and probable large vertical ion fluxes. Rapid charge exchange with atomic oxygen ensures that D/H is about equal to D(+)/H(+) at the lower altitudes where the derived D to H concentration ratio is a factor of about 6 larger than its sea level value, for an exospheric temperature of 930 K. This relative enhancement of deuterium arises from the fact that hydrogen more readily escapes the earth, and a large vertical gradient in the H concentration relative to its diffusive equilibrium value is necessary to drive this upward flux through the lower thermosphere. If these planetary losses of hydrogen are much greater than those associated with evaporative escape, as is the current view, then correspondingly larger deuterium loss rates are also likely in order that the thermospheric D/H ratio not increase well above the observed value. The absolute winter daytime concentration of deuterium at 300 km is found to be 210 + or - 50 atoms/cu cm.

  7. Low-temperature (<200 oC) solid-phase crystallization of high substitutional Sn concentration (˜10%) GeSn on insulator enhanced by weak laser irradiation

    NASA Astrophysics Data System (ADS)

    Moto, Kenta; Sugino, Takayuki; Matsumura, Ryo; Ikenoue, Hiroshi; Miyao, Masanobu; Sadoh, Taizoh

    2017-07-01

    Low temperature (<200 oC) crystallization of GeSn (substitutional Sn concentration: >8%) on insulating substrates is essential to realize next generation flexible electronics. To achieve this, a growth method of high quality GeSn films on insulating substrates by combination of laser irradiation and subsequent thermal annealing is developed. Here, the laser fluence is chosen as weak, which is below the critical fluence for crystallization of GeSn. It is clarified that for samples irradiated with weak laser fluence, complete crystallization of GeSn films is achieved by subsequent thermal annealing at ˜170 oC without incubation time. In addition, the quality of GeSn films obtained by this method is higher compared with conventional growth techniques such as melting growth by pulsed laser annealing or solid-phase crystallization (SPC) without pre-laser irradiation. Substitutional Sn concentrations in the grown layers estimated by Raman spectroscopy measurements are 8-10%, which far exceed thermal equilibrium solid-solubility of Sn in Ge (˜2%). These phenomena are explained by generation of a limited number of nuclei by weak laser irradiation and lateral SPC by subsequent thermal annealing. This method will facilitate realization of next-generation high performance devices on flexible insulating substrates.

  8. Effects of hydrogen isotopes in the irradiation damage of CLAM steel

    NASA Astrophysics Data System (ADS)

    Zhao, M. Z.; Liu, P. P.; Zhu, Y. M.; Wan, F. R.; He, Z. B.; Zhan, Q.

    2015-11-01

    The isotope effect of hydrogen in irradiation damage plays an important role in the development of reduced activation Ferritic/Martensitic steels in nuclear reactors. The evolutions of microstructures and mechanical properties of China low active martensitic (CLAM) steel subjected to hydrogen and deuterium ions irradiation are studied comparatively. Under the same irradiation conditions, larger size and smaller density of dislocation loops are generated by deuterium ion than by hydrogen ion. Irradiation hardening occurs under the ion irradiation and the hardening induced by hydrogen ion is higher than by deuterium ion. Moreover, the coarsening of M23C6 precipitates is observed, which can be explained by the solute drag mechanisms. It turns out that the coarsening induced by deuterium ion irradiation is more distinct than by hydrogen ion irradiation. No distinct variations for the compositions of M23C6 precipitates are found by a large number of statistical data after hydrogen isotopes irradiation.

  9. Characterization of deuterium clusters mixed with helium gas for an application in beam-target-fusion experiments

    SciTech Connect

    Bang, W.; Quevedo, H. J.; Bernstein, A. C.; Dyer, G.; Ihn, Y. S.; Cortez, J.; Aymond, F.; Gaul, E.; Donovan, M. E.; Barbui, M.; Bonasera, A.; Natowitz, J. B.; Albright, B. J.; Fernández, J. C.; Ditmire, T.

    2014-12-10

    We measured the average deuterium cluster size within a mixture of deuterium clusters and helium gas by detecting Rayleigh scattering signals. The average cluster size from the gas mixture was comparable to that from a pure deuterium gas when the total backing pressure and temperature of the gas mixture were the same as those of the pure deuterium gas. According to these measurements, the average size of deuterium clusters depends on the total pressure and not the partial pressure of deuterium in the gas mixture. To characterize the cluster source size further, a Faraday cup was used to measure the average kinetic energy of the ions resulting from Coulomb explosion of deuterium clusters upon irradiation by an intense ultrashort pulse. The deuterium ions indeed acquired a similar amount of energy from the mixture target, corroborating our measurements of the average cluster size. As the addition of helium atoms did not reduce the resulting ion kinetic energies, the reported results confirm the utility of using a known cluster source for beam-target-fusion experiments by introducing a secondary target gas.

  10. Characterization of deuterium clusters mixed with helium gas for an application in beam-target-fusion experiments

    DOE PAGES

    Bang, W.; Quevedo, H. J.; Bernstein, A. C.; ...

    2014-12-10

    We measured the average deuterium cluster size within a mixture of deuterium clusters and helium gas by detecting Rayleigh scattering signals. The average cluster size from the gas mixture was comparable to that from a pure deuterium gas when the total backing pressure and temperature of the gas mixture were the same as those of the pure deuterium gas. According to these measurements, the average size of deuterium clusters depends on the total pressure and not the partial pressure of deuterium in the gas mixture. To characterize the cluster source size further, a Faraday cup was used to measure themore » average kinetic energy of the ions resulting from Coulomb explosion of deuterium clusters upon irradiation by an intense ultrashort pulse. The deuterium ions indeed acquired a similar amount of energy from the mixture target, corroborating our measurements of the average cluster size. As the addition of helium atoms did not reduce the resulting ion kinetic energies, the reported results confirm the utility of using a known cluster source for beam-target-fusion experiments by introducing a secondary target gas.« less

  11. Characterization of deuterium clusters mixed with helium gas for an application in beam-target-fusion experiments

    NASA Astrophysics Data System (ADS)

    Bang, W.; Quevedo, H. J.; Bernstein, A. C.; Dyer, G.; Ihn, Y. S.; Cortez, J.; Aymond, F.; Gaul, E.; Donovan, M. E.; Barbui, M.; Bonasera, A.; Natowitz, J. B.; Albright, B. J.; Fernández, J. C.; Ditmire, T.

    2014-12-01

    We measured the average deuterium cluster size within a mixture of deuterium clusters and helium gas by detecting Rayleigh scattering signals. The average cluster size from the gas mixture was comparable to that from a pure deuterium gas when the total backing pressure and temperature of the gas mixture were the same as those of the pure deuterium gas. According to these measurements, the average size of deuterium clusters depends on the total pressure and not the partial pressure of deuterium in the gas mixture. To characterize the cluster source size further, a Faraday cup was used to measure the average kinetic energy of the ions resulting from Coulomb explosion of deuterium clusters upon irradiation by an intense ultrashort pulse. The deuterium ions indeed acquired a similar amount of energy from the mixture target, corroborating our measurements of the average cluster size. As the addition of helium atoms did not reduce the resulting ion kinetic energies, the reported results confirm the utility of using a known cluster source for beam-target-fusion experiments by introducing a secondary target gas.

  12. Characterization of deuterium clusters mixed with helium gas for an application in beam-target-fusion experiments.

    PubMed

    Bang, W; Quevedo, H J; Bernstein, A C; Dyer, G; Ihn, Y S; Cortez, J; Aymond, F; Gaul, E; Donovan, M E; Barbui, M; Bonasera, A; Natowitz, J B; Albright, B J; Fernández, J C; Ditmire, T

    2014-12-01

    We measured the average deuterium cluster size within a mixture of deuterium clusters and helium gas by detecting Rayleigh scattering signals. The average cluster size from the gas mixture was comparable to that from a pure deuterium gas when the total backing pressure and temperature of the gas mixture were the same as those of the pure deuterium gas. According to these measurements, the average size of deuterium clusters depends on the total pressure and not the partial pressure of deuterium in the gas mixture. To characterize the cluster source size further, a Faraday cup was used to measure the average kinetic energy of the ions resulting from Coulomb explosion of deuterium clusters upon irradiation by an intense ultrashort pulse. The deuterium ions indeed acquired a similar amount of energy from the mixture target, corroborating our measurements of the average cluster size. As the addition of helium atoms did not reduce the resulting ion kinetic energies, the reported results confirm the utility of using a known cluster source for beam-target-fusion experiments by introducing a secondary target gas.

  13. First-principles molecular dynamics study of deuterium diffusion in liquid tin

    NASA Astrophysics Data System (ADS)

    Liu, Xiaohui; Zheng, Daye; Ren, Xinguo; He, Lixin; Chen, Mohan

    2017-08-01

    Understanding the retention of hydrogen isotopes in liquid metals, such as lithium and tin, is of great importance in designing a liquid plasma-facing component in fusion reactors. However, experimental diffusivity data of hydrogen isotopes in liquid metals are still limited or controversial. We employ first-principles molecular dynamics simulations to predict diffusion coefficients of deuterium in liquid tin at temperatures ranging from 573 to 1673 K. Our simulations indicate faster diffusion of deuterium in liquid tin than the self-diffusivity of tin. In addition, we find that the structural and dynamic properties of tin are insensitive to the inserted deuterium at temperatures and concentrations considered. We also observe that tin and deuterium do not form stable solid compounds. These predicted results from simulations enable us to have a better understanding of the retention of hydrogen isotopes in liquid tin.

  14. Single crystal diamond detector measurements of deuterium-deuterium and deuterium-tritium neutrons in Joint European Torus fusion plasmas

    SciTech Connect

    Cazzaniga, C. Gorini, G.; Nocente, M.; Sundén, E. Andersson; Binda, F.; Ericsson, G.; Croci, G.; Grosso, G.; Cippo, E. Perelli; Tardocchi, M.; Giacomelli, L.; Rebai, M.; Griesmayer, E.; Kaveney, G.; Syme, B.; Collaboration: JET-EFDA Contributors

    2014-04-15

    First simultaneous measurements of deuterium-deuterium (DD) and deuterium-tritium neutrons from deuterium plasmas using a Single crystal Diamond Detector are presented in this paper. The measurements were performed at JET with a dedicated electronic chain that combined high count rate capabilities and high energy resolution. The deposited energy spectrum from DD neutrons was successfully reproduced by means of Monte Carlo calculations of the detector response function and simulations of neutron emission from the plasma, including background contributions. The reported results are of relevance for the development of compact neutron detectors with spectroscopy capabilities for installation in camera systems of present and future high power fusion experiments.

  15. Single crystal diamond detector measurements of deuterium-deuterium and deuterium-tritium neutrons in Joint European Torus fusion plasmas.

    PubMed

    Cazzaniga, C; Sundén, E Andersson; Binda, F; Croci, G; Ericsson, G; Giacomelli, L; Gorini, G; Griesmayer, E; Grosso, G; Kaveney, G; Nocente, M; Perelli Cippo, E; Rebai, M; Syme, B; Tardocchi, M

    2014-04-01

    First simultaneous measurements of deuterium-deuterium (DD) and deuterium-tritium neutrons from deuterium plasmas using a Single crystal Diamond Detector are presented in this paper. The measurements were performed at JET with a dedicated electronic chain that combined high count rate capabilities and high energy resolution. The deposited energy spectrum from DD neutrons was successfully reproduced by means of Monte Carlo calculations of the detector response function and simulations of neutron emission from the plasma, including background contributions. The reported results are of relevance for the development of compact neutron detectors with spectroscopy capabilities for installation in camera systems of present and future high power fusion experiments.

  16. Deuterium Gas Analysis by Residual Gas Analyzer

    NASA Astrophysics Data System (ADS)

    Das, B. K.; Shukla, R.; Das, R.; Shyam, A.; Rao, A. D. P.

    2012-11-01

    Hydrogen gas is generated by electrolysis method in a compact hydrogen generator. A simple procedure reduces handling and storage of hydrogen cylinders for laboratory applications. In such a system, we are producing deuterium gas from heavy water by electrolysis method. After production of the deuterium gas, we have checked the purity level of the outgoing deuterium from the electrolyser. The test was carried out in a high vacuum system in which one residual gas analyser (RGA) was mounted. The deuterium gas was inserted by one manual gas leak valve in to the vacuum system. In this study, the effect of the emission current of the RGA on the detection of the deuterium was performed. In this paper, we will discuss the detail analysis of the deuterium gas and the effect of the emission current on the partial pressure measurement.

  17. Deuterium thermal desorption from vacancy clusters in tungsten

    NASA Astrophysics Data System (ADS)

    Ryabtsev, S.; Gasparyan, Yu.; Zibrov, M.; Shubina, A.; Pisarev, A.

    2016-09-01

    Deuterium interaction with vacancy clusters in tungsten was studied by means of thermal desorption spectroscopy (TDS). A recrystallized W foil was used as a sample, and the vacancy clusters were formed in the bulk by irradiation with 10 keV/D ions to the fluence of 3 × 1019 D/m2 and subsequent annealing at the temperature of 800 K. Then the sample was loaded with deuterium (0.67 keV/D ions with a fluence of 1 × 1019 D/m2), and TDS measurements with varying heating rates β in the range of 0.25-4 K/s were performed. The high temperature peak with the maximum at around 700 K was attributed to deuterium desorption from vacancy clusters and the detrapping energy for this type of defects was determined from the slope of the Arrhenius-like plot ln (β / Tm2) versus 1 /Tm , where Tm is the peak position. The detrapping energy calculated this way is 2.10 ± 0.02 eV.

  18. The Diffusion of Muonic Deuterium Atoms in Deuterium Gas.

    NASA Astrophysics Data System (ADS)

    Kraiman, James Brian

    Negative muons were brought to rest in a target array consisting of 30-50 parallel plastic foils coated with Au which were separated by a few mm. The interstitial volumes between the foils were filled with deuterium gas at pressures from 0.094 bar to 1.52 bar. Muons which stopped in the deuterium formed mud atoms, which subsequently diffused through the gas until either the muon decayed or the mud atom struck a foil surface. For mud atoms impinging upon the Au layer, the muon would transfer to an Au atom, resulting in the formation of a mu Au atom in a highly excited state. De-excitation to the 1S ground state resulted in emission of characteristic muonic Au x rays, and after the muon was absorbed by the Au nucleus, the emission of Pt gamma rays. These transfer photons were detected by one of four germanium x-ray detectors adjacent to the target vessel. Analysis of the time distributions formed by collecting delayed transfer events for several sets of experimental conditions yielded information on the diffusion process of mud atoms in deuterium gas. The initial speed distribution of the mud atoms upon reaching the 1S state is described reasonably well by a Maxwellian speed distribution of mean energy 3KT/2 = 1.8 +/- 0.1 eV. The theoretical scattering cross sections for the reaction mud + d to mud + d calculated by Bubak and Faifman agree well with this experiment when the effects of molecular scattering are approximated by multiplying the nuclear cross sections by a factor of about two. It was found that a factor of 2.10 for center of mass collision energies greater than 0.30 eV, and 2.30 for collision energies less than 0.30 eV provided a good fit to the experimental data.

  19. X-Ray-induced Deuterium Enrichment of N-rich Organics in Protoplanetary Disks: An Experimental Investigation Using Synchrotron Light

    NASA Astrophysics Data System (ADS)

    Gavilan, Lisseth; Remusat, Laurent; Roskosz, Mathieu; Popescu, Horia; Jaouen, Nicolas; Sandt, Christophe; Jäger, Cornelia; Henning, Thomas; Simionovici, Alexandre; Lemaire, Jean Louis; Mangin, Denis; Carrasco, Nathalie

    2017-05-01

    The deuterium enrichment of organics in the interstellar medium, protoplanetary disks, and meteorites has been proposed to be the result of ionizing radiation. The goal of this study is to simulate and quantify the effects of soft X-rays (0.1-2 keV), an important component of stellar radiation fields illuminating protoplanetary disks, on the refractory organics present in the disks. We prepared tholins, nitrogen-rich organic analogs to solids found in several astrophysical environments, e.g., Titan’s atmosphere, cometary surfaces, and protoplanetary disks, via plasma deposition. Controlled irradiation experiments with soft X-rays at 0.5 and 1.3 keV were performed at the SEXTANTS beamline of the SOLEIL synchrotron, and were immediately followed by ex-situ infrared, Raman, and isotopic diagnostics. Infrared spectroscopy revealed the preferential loss of singly bonded groups (N-H, C-H, and R-N≡C) and the formation of sp3 carbon defects with signatures at ˜1250-1300 cm-1. Raman analysis revealed that, while the length of polyaromatic units is only slightly modified, the introduction of defects leads to structural amorphization. Finally, tholins were measured via secondary ion mass spectrometry to quantify the D, H, and C elemental abundances in the irradiated versus non-irradiated areas. Isotopic analysis revealed that significant D-enrichment is induced by X-ray irradiation. Our results are compared to previous experimental studies involving the thermal degradation and electron irradiation of organics. The penetration depth of soft X-rays in μm-sized tholins leads to volume rather than surface modifications: lower-energy X-rays (0.5 keV) induce a larger D-enrichment than 1.3 keV X-rays, reaching a plateau for doses larger than 5 × 1027 eV cm-3. Synchrotron fluences fall within the expected soft X-ray fluences in protoplanetary disks, and thus provide evidence of a new non-thermal pathway to deuterium fractionation of organic matter.

  20. Low deuterium content of Lake Vanda, Antarctica

    USGS Publications Warehouse

    Ragotzkie, R.A.; Friedman, I.

    1965-01-01

    Lake Vanda in Victoria Land, Antarctica, is permanently ice-covered and permanently stratified, with warm, salty water near the bottom. Deuterium analyses of lake water from several levels indicate that the lake has a low deuterium content, and that it is stratified with respect to this isotope. This low deuterium content supports the evidence from the lake's ionic content that the saline layer is not of marine origin, and it indicates that evaporation from the ice surface has taken place. The stratification of the lake with respect to deuterium suggests that the upper and lower layers of water were formed at different times from different sources of glacial melt water.

  1. Effect of deuterium on polystyrene degradation

    SciTech Connect

    Korshak, V.V.; Pavlova, S.S.A.; Gribkova, P.N.; Kozyreva, N.M.; Balykova, T.N.; Kirilin, A.I.

    1988-01-01

    The effect of replacing hydrogen by deuterium in polystyrene was studied on resistance to oxidative and thermal degradation. Polystyrene, polydeutero-styrene-D/sub 8/ containing 98-99 at.% deuterium, and a series of their statistical copolymers containing various proportions of deuterated and undeuterated monomer units were synthesized. The replacement of hydrogen by deuterium in polystyrene caused some increase in its resistance to thermal and oxidative destruction. A table shows that at all test temperatures, an increase in the fraction of deuterated monomer units in copolymer decreases the amounts of absorbed oxygen and evolved carbon oxides which is evidence for retadation of polystyrene oxidation when hydrogen is replaced by deuterium.

  2. Vacuum-ultraviolet photolysis of H 3CF in solid neon: Infrared spectra of HCF and CF +

    NASA Astrophysics Data System (ADS)

    Wu, Yu-Jong; Chen, Hui-Fen; Chou, Sheng-Lung; Lin, Meng-Yeh; Cheng, Bing-Ming

    2010-09-01

    Irradiation of a sample containing fluoromethane dispersed in solid neon near 3.0 K with light from a synchrotron at wavelength 124 nm generated products that were detected with infrared absorption spectra. The identified products include CF, CF+, CF2, HCF, H2CF, C2F2, C2F2H2, CH3, CH, C2H2 and HF. Isotopic labeling with 13C and deuterium and quantum-chemical calculations confirmed the identification of these species; the vibrational spectra of CF+ and HCF (CH stretching mode) are recorded for the first time in solid neon.

  3. Deuterium accelerator experiments for APT.

    SciTech Connect

    Causey, Rion A. (Sandia National Laboratories, Livermore, CA); Hertz, Kristin L. (Sandia National Laboratories, Livermore, CA); Cowgill, Donald F. (Sandia National Laboratories, Livermore, CA)

    2005-08-01

    Sandia National Laboratories in California initiated an experimental program to determine whether tritium retention in the tube walls and permeation through the tubes into the surrounding coolant water would be a problem for the Accelerator Production of Tritium (APT), and to find ways to mitigate the problem, if it existed. Significant holdup in the tube walls would limit the ability of APT to meet its production goals, and high levels of permeation would require a costly cleanup system for the cooling water. To simulate tritium implantation, a 200 keV accelerator was used to implant deuterium into Al 6061-T and SS3 16L samples at temperatures and particle fluxes appropriate for APT, for times varying between one week and five months. The implanted samples were characterized to determine the deuterium retention and Permeation. During the implantation, the D(d,p)T nuclear reaction was used to monitor the build-up of deuterium in the implant region of the samples. These experiments increased in sophistication, from mono-energetic deuteron implants to multi-energetic deuteron and proton implants, to more accurately reproduce the conditions expected in APT. Micron-thick copper, nickel, and anodized aluminum coatings were applied to the front surface of the samples (inside of the APT walls) in an attempt to lower retention and permeation. The reduction in both retention and permeation produced by the nickel coatings, and the ability to apply them to the inside of the APT tubes, indicate that both nickel-coated Al 6061-T6 and nickel-coated SS3 16L tubes would be effective for use in APT. The results of this work were submitted to the Accelerator Production of Tritium project in document number TPO-E29-Z-TNS-X-00050, APT-MP-01-17.

  4. Research on laser-removal of a deuterium deposit from a graphite sample

    NASA Astrophysics Data System (ADS)

    Kubkowska, M.; Skladnik-Sadowska, E.; Malinowski, K.; Sadowski, M. J.; Rosinski, M.; Gasior, P.

    2014-04-01

    The paper presents experimental results of investigation of a removal of deuterium deposits from a graphite target by means of pulsed laser beams. The sample was a part of the TEXTOR limiter with a deuterium-deposited layer. That target was located in the vacuum chamber, pumped out to 5×10-5 Torr, and it was irradiated with a Nd:YAG laser, which generated 3.5-ns pulses of energy of 0.5 J at λ1 = 1063 nm, or 0.1 J at λ3 = 355 nm.

  5. Was Venus wet? Deuterium reconsidered

    NASA Technical Reports Server (NTRS)

    Grinspoon, David H.

    1987-01-01

    The ratio of deuterium to hydrogen on Venus has been accepted as proof of a wetter, more earth-like part on that planet. However, the present-day water abundance and the nonthermal hydrogen escape flux on Venus imply that hydrogen is in a steady state and that a hydrogen source, most likely cometary infall, is present. An alternative interpretation of the D/H ratio is offered, in which the measured value is consistent with a steady-state evolution over the age of the solar system. No past water excess is required to explain the isotopic data.

  6. Influence of gamma irradiation on the electrical properties of LiClO4-gelatin solid polymer electrolytes: Modelling anomalous diffusion through generalized calculus

    NASA Astrophysics Data System (ADS)

    Basu, Tania; Tarafdar, Sujata

    2016-08-01

    Solid polymer electrolytes with gelatin as host polymer are subjected to gamma irradiation with dose varying from 0 to 100 kGy. Two sets of samples are studied, one with and one without addition of lithium perchlorate as ionic salt. The effect of varying plasticizer content, salt fraction and radiation dose on the impedance is measured. The dc (direct current) ion-conductivity is determined from impedance spectroscopy results. It is shown that relative to the unirradiated sample, the room temperature dc ion-conductivity decreases in general on irradiation, by an order of magnitude. However on comparing results for the irradiated samples, a dose of 60 kGy is seen to produce the highest ion-conductivity. Considering the variation of all parameters, the highest dc-conductivity of 6.06x10-2 S/m is obtained for the un-irradiated sample at room temperature, with 12.5 wt% LiClO4 and 35.71 wt% of glycerol as plasticizer. The samples are characterized in addition by XRD, SEM and FTIR respectively. Cyclic voltametry is performed for the confirmation of the electrolytic performance for pristine and gamma irradiated samples. To understand the experimental results, a model incorporating normal, as well as anomalous diffusion has been applied. Generalized calculus is used to model the anomalous diffusion. It is shown that this model successfully reproduces the experimental frequency dependence of the complex impedance for samples subjected to varying gamma dose. The physical interpretation of the model parameters and their variation with sample composition and irradiation dose is discussed.

  7. Vanadium hydride deuterium-tritium generator

    DOEpatents

    Christensen, Leslie D.

    1982-01-01

    A pressure controlled vanadium hydride gas generator to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

  8. Fundamental mechanisms of deuterium retention in lithiated graphite plasma facing surfaces

    NASA Astrophysics Data System (ADS)

    Taylor, Chase N.

    Plasma impurities and undesirable deuterium recycling degrade plasma confinement and impede a sustainable fusion reaction. This occurs by inducing plasma instabilities and reducing plasma temperature. Lithium wall conditioning has been used in fusion devices including TFTR, CDX-U, FTU, TJ-II, MAST and NSTX as a means to reduce plasma impurities and improve deuterium retention, resulting in significant enhancements in plasma performance. These improvements have come via a reduction in deuterium recycling in addition to a reduction in oxygen and carbon impurities. NSTX, with ATJ graphite walls, is the leading fusion device in lithium research. Many previous studies have investigated deuterated lithium, deuterated graphite, and lithiated graphite in order to understand fundamental properties and particular applications. Deuterium irradiation of lithiated graphite studies are few in number and no systematic research has been conducted to determine the fundamental mechanisms by which deuterium is retained in lithiated graphite. This work presents controlled laboratory studies that use X-ray photoelectron spectroscopy (XPS) to identify the fundamental chemical interactions in lithiated graphite. Li-O chemical interactions are observed in the photoelectron energy spectrum at 529.5 eV after thermally depositing lithium onto ATJ graphite. Deuterium retention induces Li-O-D and Li-C-D interactions which are observed at 529.9 eV and 291.2 eV, respectively. Examination of NSTX post-mortem tiles confirms the formation of Li-O-D and Li-C-D chemical interactions and validates the procedures in these experiments. Prior to these findings, deuterium was assumed to bind exclusively with lithium to form stoichiometric LiD. Instead, we find that in a graphite matrix, lithium will always bind with oxygen and carbon (when present) prior to the introduction of deuterium. The deuterium saturation of lithiated graphite is also assessed using XPS and results indicate that saturation occurs

  9. Deuterium depth distribution study in Yb

    NASA Astrophysics Data System (ADS)

    Guan, Xing-Cai; Lu, Yong-Kai; He, Hou-Jun; Zhao, Jiang-Tao; Wang, Qiang; Fang, Kai-Hong; Meng, Xuan; Wang, Tie-Shan; Kasagi, Jirohta

    2017-05-01

    The deuterium depth distribution for a , while beam implanted into ytterbium (Yb) at a temperature between 300 and 340 K was studied using the D(d,p)T reaction. By analyzing the proton yields, the deuterium depth distribution from the front surface to 500 nm depth was found. The results indicate that an equilibrium deuterium distribution region from the front surface to a depth approximately equal to the mean range of implanted deuterons was formed in Yb during the implantation. The deduced deuterium concentration in the equilibrium deuterium distribution region was D/Yb = 22%. Supported by National Natural Science Foundation of China (11275085, 11305080, 11405079 and 11505086), Fundamental Research Funds for Central University of China (lzujbky-2015-69 and lzujbky-2016-36).

  10. Absolute measurement of the photodisintegration of deuterium

    SciTech Connect

    Knott, J.E.

    1988-01-01

    This experiment measured the differential cross section for deuteron photodisintegration between photon energies of 63 and 71 MeV. The photon beam was produced by the bremsstrahlung of an 88.4 MeV CW electron beam, from the University of Illinois Nuclear Physics Laboratory electron microtron, in a 1.4 {times} 10{sup {minus}3} radiation length aluminum converter. The photon energy was determined to .25 MeV by the technique of bremsstrahlung tagging. The deuterium target gas, at atmospheric pressure, was contained in a thin walled cylinder 2.4 m long. The protons from deuteron photo-disintegration were detected in the LArge Solid Angle detector, which was built for this experiment. The LASA detector consists of three concentric, cylindrical MWPC chambers surrounded by segmented plastic scintillators. The target cylinder is on the axis of the chamber. Particles were collected from 20{degrees} to 160{degrees}, the angle determined by the charge division technique in the wire chamber. The de/dx measurements in the wire chamber and the scintillators allowed the separation of protons from electrons. The differential cross sections have been fit by Legendre polynomials. These results are in reasonable agreement with previous experiments and theoretical calculations.

  11. Hot muonic deuterium and tritium from cold targets

    SciTech Connect

    Marshall, G.M.; Beveridge, J.L. ); Bailey, J.M. ); Beer, G.A.; Knowles, P.E.; Mason, G.R.; Olin, A. ); Brewer, J.H.; Forster, B.M. ); Huber, T.M.; Pippitt, B. ); Jacot-Guillarmod, R.; Schellenberg, L. (Fribourg U

    1992-01-01

    Experiments are described which use a solid hydrogen layer to form muonic hydrogen isotopes in vacuum. The method relies on transfer of the muon from protium to either a deuteron or a triton. The resulting muonic deuterium or muonic tritium will not immediately thermalize because of the very low elastic cross sections, and may be emitted from the surface of the layer. Measurements which detect decay electrons, muonic x-rays, and fusion products have been used to study the processes. A target has been constructed which exploits muonic atom emission in order to study the energy dependence of transfer and muon molecular formation.

  12. Hot muonic deuterium and tritium from cold targets

    SciTech Connect

    Marshall, G.M.; Beveridge, J.L.; Bailey, J.M.; Beer, G.A.; Knowles, P.E.; Mason, G.R.; Olin, A.; Brewer, J.H.; Forster, B.M.; Huber, T.M.; Pippitt, B.; Jacot-Guillarmod, R.; Schellenberg, L.; Kammel, P.; Zmeskal, J.; Kunselman, A.R.; Martoff, C.J.; Petitjean, C.

    1992-12-31

    Experiments are described which use a solid hydrogen layer to form muonic hydrogen isotopes in vacuum. The method relies on transfer of the muon from protium to either a deuteron or a triton. The resulting muonic deuterium or muonic tritium will not immediately thermalize because of the very low elastic cross sections, and may be emitted from the surface of the layer. Measurements which detect decay electrons, muonic x-rays, and fusion products have been used to study the processes. A target has been constructed which exploits muonic atom emission in order to study the energy dependence of transfer and muon molecular formation.

  13. Regiospecific one-pot synthesis of pyrimido[4,5-d]pyrimidine derivatives in the solid state under microwave irradiations.

    PubMed

    Prajapati, Dipak; Gohain, Mukut; Thakur, Ashim J

    2006-07-01

    Electron rich 6-[(dimethylamino)methylene]amino uracil 1, undergoes [4+2] cycloaddition reactions with various in situ generated glyoxylate imine and imine oxides 6 to provide novel pyrimido[4,5-d]pyrimidine derivatives of biological significance, after elimination of dimethylamine from the (1:1) cycloadducts and oxidative aromatisation. This procedure provides a convenient method for the direct synthesis of pyrimido[4,5-d]pyrimidines in excellent yields when carried out in the solid state and under microwave irradiations.

  14. Lamb shift in muonic deuterium

    SciTech Connect

    Gorchtein, Mikhail; Vanderhaeghen, Marc; Carlson, Carl E.

    2013-11-07

    We consider the two-photon exchange contribution to the 2P-2S Lamb shift in muonic deuterium in the framework of forward dispersion relations. The dispersion integrals are evaluated with minimal model dependence using experimental data on elastic deuteron form factors and inelastic electron-deuteron scattering, both in the quasielastic and hadronic range. The subtraction constant that is required to ensure convergence of the dispersion relation for the forward Compton amplitude T{sub 1} (ν,Q{sup 2}) is related to the deuteron magnetic polarizability β(Q{sup 2}) and represents the main source of uncertainty in our analysis. We obtain for the Lamb shift ΔE{sub 2P-2S} = 1.620±0.190 meV and discuss ways to further reduce this uncertainty.

  15. Deuterium and the stellar birthline

    NASA Technical Reports Server (NTRS)

    Stahler, Steven W.

    1988-01-01

    A series of simplified evolutionary calculations are used to show that deuterium burning acts as an effective thermostat in low-mass protostars over a plausible range of initial conditions and mass accretion rates. The thermostat keeps the central temperature of the accreting hydrostatic core close to 10 to the 6th K, and thereby tightly constrains the core's mass-radius relation. This relation, when combined with premain-sequence evolutionary tracks, yields a theoretical birthline or upper envelope for young stars in the H-R diagram which maintains excellent agreement with observations of T Tauri stars in nearby molecular cloud complexes. This derivation of the birthline helps to explain its insensitivity to protostellar collapse conditions. The calculations indicate that the birthline will be little affected by the inclusion of rotation as long as the newly visible stars have lost most of their accreted angular momentum.

  16. In vivo NMR imaging of deuterium

    NASA Astrophysics Data System (ADS)

    Müller, S.; Seelig, J.

    D 2O is used as a contrast agent for studying anatomical images and flow in vivo by deuterium NMR. A deuterium image of the head of a living rat after administration of D 2O (5% v/v) in the drinking water is shown. It was obtained in 14 min with a surface coil and has a spatial resolution of about one millimeter. The application of D 2O as a tracer is discussed and the inflow of heavy water into the brain of a rat is recorded in a time series of deuterium images. Spatially resolved inflow time constants have been determined.

  17. All-proportional solid-solution Rh-Pd-Pt alloy nanoparticles by femtosecond laser irradiation of aqueous solution with surfactant

    NASA Astrophysics Data System (ADS)

    Sarker, Md. Samiul Islam; Nakamura, Takahiro; Sato, Shunichi

    2015-06-01

    Formation of Rh-Pd-Pt solid-solution alloy nanoparticles (NPs) by femtosecond laser irradiation of aqueous solution in the presence of polyvinylpyrrolidone (PVP) or citrate as a stabilizer was studied. It was found that the addition of surfactant (PVP or citrate) significantly contributed to reduce the mean size of the particles to 3 nm for PVP and 10 nm for citrate, which was much smaller than that of the particles fabricated without any surfactants (20 nm), and improved the dispersion state as well as the colloidal stability. The solid-solution formation of the Rh-Pd-Pt alloy NPs was confirmed by the XRD results that the diffraction pattern was a single peak, which was found between the positions corresponding to each pure Rh, Pd, and Pt NPs. Moreover, all the elements were homogeneously distributed in every particle by STEM-EDS elemental mapping, strongly indicating the formation of homogeneous solid-solution alloy. Although the Rh-Pd-Pt alloy NPs fabricated with PVP was found to be Pt rich by EDS observation, the composition of NPs fabricated with citrate almost exactly preserved the feeding ratio of ions in the mixed solution. To our best knowledge, these results demonstrated for the first time, the formation of all-proportional solid-solution Rh-Pd-Pt alloy NPs with well size control.

  18. In Quest of the Alanine R3 Radical: Multivariate EPR Spectral Analyses of X-Irradiated Alanine in the Solid State.

    PubMed

    Jåstad, Eirik O; Torheim, Turid; Villeneuve, Kathleen M; Kvaal, Knut; Hole, Eli O; Sagstuen, Einar; Malinen, Eirik; Futsaether, Cecilia M

    2017-09-28

    The amino acid l-α-alanine is the most commonly used material for solid-state electron paramagnetic resonance (EPR) dosimetry, due to the formation of highly stable radicals upon irradiation, with yields proportional to the radiation dose. Two major alanine radical components designated R1 and R2 have previously been uniquely characterized from EPR and electron-nuclear double resonance (ENDOR) studies as well as from quantum chemical calculations. There is also convincing experimental evidence of a third minor radical component R3, and a tentative radical structure has been suggested, even though no well-defined spectral signature has been observed experimentally. In the present study, temperature dependent EPR spectra of X-ray irradiated polycrystalline alanine were analyzed using five multivariate methods in further attempts to understand the composite nature of the alanine dosimeter EPR spectrum. Principal component analysis (PCA), maximum likelihood common factor analysis (MLCFA), independent component analysis (ICA), self-modeling mixture analysis (SMA), and multivariate curve resolution (MCR) were used to extract pure radical spectra and their fractional contributions from the experimental EPR spectra. All methods yielded spectral estimates resembling the established R1 spectrum. Furthermore, SMA and MCR consistently predicted both the established R2 spectrum and the shape of the R3 spectrum. The predicted shape of the R3 spectrum corresponded well with the proposed tentative spectrum derived from spectrum simulations. Thus, results from two independent multivariate data analysis techniques strongly support the previous evidence that three radicals are indeed present in irradiated alanine samples.

  19. White-light emission from solid carbon in aqueous solution during hydrogen generation induced by nanosecond laser pulse irradiation

    NASA Astrophysics Data System (ADS)

    Akimoto, Ikuko; Yamamoto, Shota; Maeda, Kosuke

    2016-07-01

    We previously discovered a novel method of hydrogen generation from high-grade charcoal in an aqueous solution using nanosecond laser pulse irradiation. In this paper, white-light emission during this reaction is reported: A broad spectrum over the visible range is observed above a threshold excitation energy density. The white-light emission is a simultaneous product of the hydrogen generation reaction and is attributed to blackbody radiation in accordance with Planck's Law at a temperature above 3800 K. Consequently, we propose that hydrogen generation induced by laser irradiation proceeds similarly to classical coal gasification, which features reactions at high pressure and high temperature.

  20. Phonon Localization by Mass Disorder in Dense Hydrogen-Deuterium Binary Alloy

    NASA Astrophysics Data System (ADS)

    Howie, Ross T.; Magdǎu, Ioan B.; Goncharov, Alexander F.; Ackland, Graeme J.; Gregoryanz, Eugene

    2014-10-01

    Using a combination of the Raman spectroscopy and density functional theory calculations on dense hydrogen-deuterium mixtures of various concentrations, we demonstrate that, at 300 K and above 200 GPa, they transform into phase IV, forming a disordered binary alloy with six highly localized intramolecular vibrational (vibrons) and four delocalized low-frequency (<1200 cm-1) modes. Hydrogen-deuterium mixtures are unique in showing a purely mass-induced localization effect in the quantum solid: chemical bonding is isotope-independent while the mass varies by a factor of 2.

  1. Irradiation of Fe-Mn Supersaturated Solid Solution with Ions of Various Atomic Masses (Ar+, Xe+) and Analysis of the Role of Nanosized Dynamic Effects in the Activation Processes of Long-Range Type

    NASA Astrophysics Data System (ADS)

    Ovchinnikov, V. V.; Makhin'ko, F. F.; Semionkin, V. A.; Shalomov, K. V.

    2017-05-01

    A multiple increase in the atom mobility in metastable supersaturated (quenched from 850 °C) Fe-8.16 at % Mn solid solution is detected at temperatures less than 250°C under irradiation with 5-keV Ar+ and Xe+ ions of different masses. The irradiation-induced atom redistribution in the entire volume of foils 30 μm thick at a projected Ar+ and Xe+ ion ranges as much as 20-30 nm only is found and studied by the transmission Mössbauer spectroscopy. Long-range effects at low irradiation doses and anomalously low temperatures are attributed to “radiation shaking” of metastable media with post-cascade solitary waves in contrast to thermally stimulated radiation-enhanced processes in the narrow nanoscale near-surface layers of the alloy. It has been shown that heavier Xe+ ions at higher irradiation doses have a stronger impact on the solid solution than Ar+ ions.

  2. Energy Levels of Hydrogen and Deuterium

    National Institute of Standards and Technology Data Gateway

    SRD 142 Energy Levels of Hydrogen and Deuterium (Web, free access)   This database provides theoretical values of energy levels of hydrogen and deuterium for principle quantum numbers n = 1 to 200 and all allowed orbital angular momenta l and total angular momenta j. The values are based on current knowledge of the revelant theoretical contributions including relativistic, quantum electrodynamic, recoil, and nuclear size effects.

  3. Vanadium hydride deuterium-tritium generator

    DOEpatents

    Christensen, L.D.

    1980-03-13

    A pressure controlled vanadium hydride gas generator was designed to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

  4. Deuterium absorption and material phase characteristics of SAES St 198 Zr-Fe Alloy. Revision 1

    SciTech Connect

    Nobile, A.; Mosley, W.C.; Holder, J.S.; Brooks, K.N.

    1994-01-01

    This document reports deuterium absorption and material phase characteristics of SAES St 198 Zr-Fe Alloy (76.5% Zr). Scanning electron microscope images of polished surfaces, electron probe microanalysis, and x-ray powder diffractometry indicated the presence of a primary Zr{sub 2}Fe phase with secondary phases of ZrFe{sub 2}, Zr{sub 5}FeSn, {alpha}-Zr, and Zr{sub 6}Fe{sub 3}O. A statistically designed experiment to determine the effects of temperature, time, and vacuum quality on activation of St 198 revealed that, when activated at low temperature (350C), deuterium absorption rate was slower when the vacuum quality was poor (2.5 Pa vs. 3 {times} 10{sup {minus}4} Pa). However, at higher activation temperature (500C), deuterium absorption rate was fast and was independent of vacuum quality. Deuterium pressure-composition-temperature (P-C-T) data are reported for St 198 in the temperature range 200 to 500C. The P-C-T data over the full range of deuterium loading and at temperatures of 350C and below is described an expression. At higher temperatures, one or more secondary reactions in the solid phase occur that slowly consume D{sub 2} from the gas phase. X-ray diffraction and other data suggest these reactions to be: 2 Zr{sub 2}FeD{sub x} {yields} xZrD{sub 2} + x/3 ZrFe{sub 2} + (2 {minus} 2/3x) Zr{sub 2}Fe and Zr{sub 2}FeD{sub x} + (2 {minus} 1/2x) D{sub 2} {yields} 2 ZrD{sub 2} + Fe, where 0 < x < 3. Reaction between gas-phase deuterium and Zr{sub 2}Fe formed in the first reaction accounts for the observed consumption of deuterium from the gas phase by this reaction.

  5. Deuterium burning in objects forming via the core accretion scenario. Brown dwarfs or planets?

    NASA Astrophysics Data System (ADS)

    Mollière, P.; Mordasini, C.

    2012-11-01

    Aims: Our aim is to study deuterium burning in objects forming according to the core accretion scenario in the hot and cold start assumption and what minimum deuterium burning mass limit is found for these objects. We also study how the burning process influences the structure and luminosity of the objects. Furthermore we want to test and verify our results by comparing them to already existing hot start simulations which did not consider, however, the formation process. Methods: We present a new method to calculate deuterium burning of objects in a self-consistently coupled model of planet formation and evolution. We discuss which theory is used to describe the process of deuterium burning and how it was implemented. Results: We find that the objects forming according to a hot start scenario behave approximately in the same way as found in previous works of evolutionary calculations, which did not consider the formation. However, for cold start objects one finds that the objects expand during deuterium burning instead of being partially stabilized against contraction. In both cases, hot and cold start, the mass of the solid core has an influence on the minimum mass limit of deuterium burning. The general position of the mass limit, 13 MJ, stays however approximately the same. None of the investigated parameters was able to change this mass limit by more than 0.8 MJ. Due to deuterium burning, the luminosity of hot and cold start objects becomes comparable after ~200 Myr. Numerical data are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/547/A105

  6. Site occupancy of interstitial deuterium atoms in face-centred cubic iron

    NASA Astrophysics Data System (ADS)

    Machida, Akihiko; Saitoh, Hiroyuki; Sugimoto, Hidehiko; Hattori, Takanori; Sano-Furukawa, Asami; Endo, Naruki; Katayama, Yoshinori; Iizuka, Riko; Sato, Toyoto; Matsuo, Motoaki; Orimo, Shin-Ichi; Aoki, Katsutoshi

    2014-09-01

    Hydrogen composition and occupation state provide basic information for understanding various properties of the metal-hydrogen system, ranging from microscopic properties such as hydrogen diffusion to macroscopic properties such as phase stability. Here the deuterization process of face-centred cubic Fe to form solid-solution face-centred cubic FeDx is investigated using in situ neutron diffraction at high temperature and pressure. In a completely deuterized specimen at 988 K and 6.3 GPa, deuterium atoms occupy octahedral and tetrahedral interstitial sites with an occupancy of 0.532(9) and 0.056(5), respectively, giving a deuterium composition x of 0.64(1). During deuterization, the metal lattice expands approximately linearly with deuterium composition at a rate of 2.21 Å3 per deuterium atom. The minor occupation of the tetrahedral site is thermally driven by the intersite movement of deuterium atoms along the ‹111› direction in the face-centred cubic metal lattice.

  7. Deuterium microscopy using 17 MeV deuteron-deuteron scattering

    NASA Astrophysics Data System (ADS)

    Reichart, Patrick; Moser, Marcus; Greubel, Christoph; Peeper, Katrin; Dollinger, Günther

    2016-03-01

    Using 17 MeV deuterons as a micrometer focused primary beam, we performed deuterium microscopy by using the deuteron-deuteron (dd) scattering reaction. We describe our new box like detector setup consisting of four double sided silicon strip detectors (DSSSD) with 16 strips on each side, each covering up to 0.5 sr solid angle for coincidence detection. This method becomes a valuable tool for studies of hydrogen incorporation or dynamic processes using deuterium tagging. The background from natural hydrocarbon or water contamination is reduced by the factor 150 ppm of natural abundance of deuterium in hydrogen. Deuterium energies of up to 25 MeV, available at the microprobe SNAKE, are ideal for the analysis of thin freestanding samples so that the scattered particles are transmitted to the detector. The differential cross section for the elastic scattering reaction is about the same as for pp-scattering (~100 mb/sr). The main background due to nuclear reactions is outside the energy window of interest. Deuteron-proton (dp) scattering events give an additional signal for hydrogen atoms, so the H/D-ratio can be monitored in parallel. A deuterium detection limit due to accidental coincidences of 3 at-ppm down to less than 1 at-ppm is demonstrated on deuterated polypropylen sheets as well as thick polycarbonate sheets after various stages of coincidence filtering that is possible with our granular detector.

  8. In situ characterization of thermal conductivities of irradiated solids by using ion beam heating and infrared imaging

    NASA Astrophysics Data System (ADS)

    Mondrik, Nicholas; Gigax, Jonathan; Wang, Xuemei; Price, Lloyd; Wei, Chaochen; Shao, Lin

    2014-08-01

    We propose a method to characterize thermal properties of ion irradiated materials. This method uses an ion beam as a heating source to create a hot spot on sample surface. Infrared imaging is used as a surface temperature mapping tool to record hot zone spreading. Since ion energy, ion flux, and ion penetration depth can be precisely controlled, the beam heating data is highly reliable and repeatable. Using a high speed infrared camera to capture lateral spreading of the hot zone, thermal diffusivity can be readily extracted. The proposed method has advantages in studying radiation induced thermal property changes, for which radiation damage can be introduced by using an irradiating beam over a relatively large beam spot and beam heating can be introduced by using a focused testing beam over a relatively small beam spot. These two beams can be switched without breaking vacuum. Thus thermal conductivity changes can be characterized in situ with ion irradiation. The feasibility of the technique is demonstrated on a single crystal quartz substrate.

  9. Effect of output power, target temperature, and solid concentration on the solubilization of waste activated sludge using microwave irradiation.

    PubMed

    Park, Woon-Ji; Ahn, Johng-Hwa; Hwang, Seokhwan; Lee, Chan-Ki

    2010-01-01

    In this paper, we quantify the effect of heating pretreatment on the degree of solubilization of waste activated sludge. The pretreatment process was carried out using a lab-scale industrial microwave unit (2450 MHz frequency). Response surface analysis was applied to determine the combination of output power (400-1600 W), target temperature (60-120 degrees C), and total solid concentration (1-3% total solid (TS)). The power, temperature, and TS concentration significantly affected the solubilization degree of sludge. Within the design boundaries, the conditions predicted to maximize the solubilization degree of 17.9% were determined to be 400 W, 102 degrees C, and 2.3% TS.

  10. Ionization and acceleration of heavy ions in high-Z solid target irradiated by high intensity laser

    NASA Astrophysics Data System (ADS)

    Kawahito, D.; Kishimoto, Y.

    2016-05-01

    In the interaction between high intensity laser and solid film, an ionization dynamics inside the solid is dominated by fast time scale convective propagation of the internal sheath field and the slow one by impact ionization due to heated high energy electrons coupled with nonlocal heat transport. Furthermore, ionization and acceleration due to the localized external sheath field which co- propagates with Al ions constituting the high energy front in the vacuum region. Through this process, the maximum charge state and then q/A increase in the rear side, so that ions near the front are further accelerated to high energy.

  11. Deuterium enrichment of interstellar dusts

    NASA Astrophysics Data System (ADS)

    Das, Ankan; Chakrabarti, Sandip Kumar; Majumdar, Liton; Sahu, Dipen

    2016-07-01

    High abundance of some abundant and simple interstellar species could be explained by considering the chemistry that occurs on interstellar dusts. Because of its simplicity, the rate equation method is widely used to study the surface chemistry. However, because the recombination efficiency for the formation of any surface species is highly dependent on various physical and chemical parameters, the Monte Carlo method is best suited for addressing the randomness of the processes. We carry out Monte-Carlo simulation to study deuterium enrichment of interstellar grain mantle under various physical conditions. Based on the physical properties, various types of clouds are considered. We find that in diffuse cloud regions, very strong radiation fields persists and hardly a few layers of surface species are formed. In translucent cloud regions with a moderate radiation field, significant number of layers would be produced and surface coverage is mainly dominated by photo-dissociation products such as, C, CH_3, CH_2D, OH and OD. In the intermediate dense cloud regions (having number density of total hydrogen nuclei in all forms ˜2 × 10^4 cm^{-3}), water and methanol along with their deuterated derivatives are efficiently formed. For much higher density regions (˜10^6 cm^{-3}), water and methanol productions are suppressed but surface coverage of CO, CO_2, O_2, O_3 are dramatically increased. We find a very high degree of fractionation of water and methanol. Observational results support a high fractionation of methanol but surprisingly water fractionation is found to be low. This is in contradiction with our model results indicating alternative routes for de-fractionation of water.

  12. 1-Dodecane-sulfonic-acid-sodium-salt(LAS) assisted hydrothermal synthesis of CdxZn1-xS solid solution as efficient photocatalysts under visible light irradiation

    NASA Astrophysics Data System (ADS)

    Jia, B.; Guo, L. J.

    2010-03-01

    With anionic surfactant LAS assisted, series of zinc cadmium sulfide semiconductor photocatalysts were synthesized by hydrothermal method. These products were characterized by X-ray diffraction (XRD), UV-Vis absorption spectra (UV-Vis) and scanning electron microscopy (FESEM). The photocatalytic activities of as-prepared samples were evaluated by photocatalytic hydrogen production from water under visible-light irradiation. The best synthesis parameters are: Composition 0.9:0.1 (Cd:Zn molar ratio), Temperature 160 °C, Hydrothermal Time 48 Hour, LAS Concentration 1.7 mmol/L, the maximum visible-light-catalytic hydrogen production rate is 161.25 μmol/h (λ>430 nm) which is higher than those of by coprecipitation method. The experiment results indicate that surfactant assisted hydrothermal method is an effective way to get highly active CdZnS solid solution photocatalyst.

  13. Quinary wurtzite Zn-Ga-Ge-N-O solid solutions and their photocatalytic properties under visible light irradiation

    PubMed Central

    Xie, Yinghao; Wu, Fangfang; Sun, Xiaoqin; Chen, Hongmei; Lv, Meilin; Ni, Shuang; Liu, Gang; Xu, Xiaoxiang

    2016-01-01

    Wurtzite solid solutions between GaN and ZnO highlight an intriguing paradigm for water splitting into hydrogen and oxygen using solar energy. However, large composition discrepancy often occurs inside the compound owing to the volatile nature of Zn, thereby prescribing rigorous terms on synthetic conditions. Here we demonstrate the merits of constituting quinary Zn-Ga-Ge-N-O solid solutions by introducing Ge into the wurtzite framework. The presence of Ge not only mitigates the vaporization of Zn but also strongly promotes particle crystallization. Synthetic details for these quinary compounds were systematically explored and their photocatalytic properties were thoroughly investigated. Proper starting molar ratios of Zn/Ga/Ge are of primary importance for single phase formation, high particle crystallinity and good photocatalytic performance. Efficient photocatalytic hydrogen and oxygen production from water were achieved for these quinary solid solutions which is strongly correlated with Ge content in the structure. Apparent quantum efficiency for optimized sample approaches 1.01% for hydrogen production and 1.14% for oxygen production. Theoretical calculation reveals the critical role of Zn for the band gap reduction in these solid solutions and their superior photocatalytic acitivity can be understood by the preservation of Zn in the structure as well as a good crystallinity after introducing Ge. PMID:26755070

  14. L-shell emission from high-Z solid targets by intense 10{sup 19}W/cm{sup 2} irradiation with a 248nm laser

    SciTech Connect

    Nelson, T.R.; Borisov, A.B.; Boyer, K.

    2000-01-05

    Efficient (1.2% yield) multikilovolt x-ray emission from Ba(L) (2.4--2.8{angstrom}) and Gd(L) (1.7--2.1{angstrom}) is produced by ultraviolet (248nm) laser-excited BaF{sub 2} and Gd solids. The high efficiency is attributed to an inner shell-selective collisional electron ejection. Much effort has been expended recently in attempts to develop an efficient coherent x-ray source suitable for high-resolution biological imaging. To this end, many experiments have been performed studying the x-ray emissions from high-Z materials under intense (>10{sup 18}W/cm{sup 2}) irradiation, with the most promising results coming from the irradiation of Xe clusters with a UV (248nm) laser at intensities of 10{sup 18}--10{sup 19}W/cm{sup 2}. In this paper the authors report the production of prompt x-rays with energies in excess of 5keV with efficiencies on the order of 1% as a result of intense irradiation of BaF{sub 2} and Gd targets with a terawatt 248nm laser. The efficiency is attributed to an inner shell-selective collisional electron ejection mechanism in which the previously photoionized electrons are ponderomotively driven into an ion while retaining a portion of their atomic phase and symmetry. This partial coherence of the laser-driven electrons has a pronounced effect on the collisional cross-section for the electron ion interaction.

  15. Surface Response of Lithium Coatings on High Z Refractory Metal under Deuterium And Helium Ion Bombardment

    NASA Astrophysics Data System (ADS)

    Neff, Anton L.

    Lithium has proven to be a very interesting plasma facing component (PFC) material. It has been used as a wall coating in multiple research tokamaks, and at many of these facilities, lithium has improved confinement time by reducing hydrogen recycling from the walls of the reactor. Tungsten is also being considered as a durable PFC for fusion environments. The International Tokamak Experimental Reactor (ITER) will use a full tungsten divertor. Many operating tokamaks are using ITER like walls for testing ITER designs. From these tests and from controlled experiments, tungsten has shown some detrimental material changes under low energy deuterium and helium ion irradiation. Some of these material defects are holes, bubbles, voids, and fuzz. Because of the use of lithium in a number of tokamaks and the use of tungsten in many test reactors as well, studies have begun to study the behavior of lithium on the refractory metal tungsten. These studies deposited 100 and 500 nm of lithium on commercial tungsten discs and irradiated them with 100 eV deuterium, 1 keV helium, and deuterium and helium from two separate ion guns. The thicknesses of the lithium layers were determined by the temperature of the evaporator, over time, entered into a model using the Knudsen equation combined with an effusion model. This model was verified using AFM scans and SEM cross section micrographs of lithium layers on silicon substrates. Irradiations were carried out to a medium deuterium fluence of (1-3)x1017 D+/cm2. The surface chemistry of the samples before, after, and during irradiation was characterized using x-ray electron spectroscopy (XPS) in situ. These studies show that lithium on tungsten retains deuterium in a similar manner as does lithium on carbon; however, when helium is a secondary ion during irradiation, it can inhibit the deuterium retention in the lithium. In addition, the lithium is not eroded from the surface of the tungsten at the fluences that were achieved is this

  16. Continuous irradiation induced luminescence from benzophenone, 4,4{prime}-dichlorobenzophenone, and 4-(dimethylamino)benzaldehyde in solid environments and its pressure dependence

    SciTech Connect

    Dreger, Z.A.; Drickamer, H.G.

    1997-02-20

    We report a strong emission change induced by continuous light irradiation in two ketones, benzophenone and 4,4{prime}-dichlorobenzophenone, and an aldehyde, 4-(dimethylamino)benzaldehyde, in their crystalline state as well as dissolved in solid polymers. With prolonged laser irradiation, a time evolution of the emission intensity shows complex features, but two clear competing trends can be distinguished: an increase and/or decrease of the emission intensity. It is shown that these trends may be a result of creation of either an emissive or a nonemissive species. The relative importance of these two pathways is significantly dependent on the type of medium and external pressure. The most characteristic feature of these dependencies is the fact that in crystalline environments, in contrast to polymers, the emission intensity at all pressures only decreases. A kinetic model is developed that assumes the lowest triplet state as the origin of the high photoreactivity of these molecules, causing their emission intensity change. This model embraces the observations either in crystalline or polymeric environments and is solved for two limiting cases: a predominance of the hydrogen abstraction reaction from the polymer or a predominance of the ionization due to biphotonic excitation of the triplet state. These processes are assumed responsible, respectively, for the creation of emissive and nonemissive photoproducts. 29 refs., 19 figs., 2 tabs.

  17. Modifications under irradiation of a self-assembled monolayer grafted on a nano-porous silica glass: a solid-state NMR characterization

    SciTech Connect

    Le Caer, S.; Chatelain, C.; Renault, J.Ph.; Brunet, F.; Charpentier, T.; Durand, D.; Dauvois, V.

    2012-02-15

    Controlled pore glasses with a pore size of 8 nm are grafted with chlorodimethylsilane (ClSi(CH{sub 3}){sub 2}H). The surface of the glass is carefully characterized before and after irradiation with 10 MeV electrons by solid-state NMR measurements. {sup 1}H MAS NMR experiments in one and two dimensions (2D double quantum and 2D exchange) have been used to reveal the grafting of the chlorodimethylsilane at the silica surface and evidence the formation of a homogeneous layer on the surface. Irradiation leads to a high H{sub 2} yield (3.3 * 10{sup -7} mol/J) due to the efficient cleavage of the Si H bond. Methane is detected in smaller quantities (5.5 * 10{sup -8} mol/J), indicating that the Si-H bond is preferentially cleaved over the Si-C bond. The H{sub 2} production arising from OH groups on the surface is very minor in comparison to the S- H and Si-C radiolysis. (authors)

  18. Comparison of line x-ray emission from solid and porous nano-layer coated targets irradiated by double laser pulses

    SciTech Connect

    Fazeli, R.; Mahdieh, M. H.

    2015-11-15

    Enhancement of line x-ray emission from both solid and porous iron targets induced by irradiation of single and double laser pulses is studied numerically. The line emission from laser produced plasma is calculated within the extreme ultra-violet lithography wavelength range of 13.5–13.7 nm. The effects of pre-pulse intensity and delay time between two pulses (pre-pulse and main pulse) are examined. The results show that using double pulses irradiation in the conditions of porous target can reduce the x-ray enhancement. According to the results, the use of both pre-pulse and porous target leads to efficient absorption of the laser energy. Calculations also show that such enhanced laser absorption can ionize atoms of the target material to very high degrees of ionization, leading to decrease of the density of appropriate ions that are responsible for line emission in the selected wavelength region. By increasing the target porosity, x-ray yield was more reduced.

  19. Extreme states of matter in solids under short-pulse laser irradiation: a molecular-dynamics study

    NASA Astrophysics Data System (ADS)

    Lorazo, Patrick; Lewis, Laurent J.; Meunier, Michel

    2004-03-01

    The thermodynamic pathways through which a silicon target---initially in a hot, highly pressurized state---dilutes into vacuum as a result of short-pulse laser irradiation, are thoroughly investigated. This is accomplished by (1) using a combined molecular-dynamics and Monte Carlo approach to describe atom and carrier dynamics, respectively, and (2) following the thermodynamic evolution of the system during heating, expansion, and cooling [1]. Our results indicate a pulse duration upper limit for phase explosion in metals and semiconductors of ˜ 10-11s. For longer pulses, fragmentation, as originally proposed by Perez and Lewis for fs irradiation [1], remains the only relevant ablation mechanism [2]. Fragmentation can thus be viewed as the missing link in short-pulse laser ablation as it explains (1) the disappearance of Newton rings in the fs regime far from the ablation threshold, and (2) the matter removal dynamics with ``long''(> 10-11s) pulse durations. [1] D. Perez and L. J. Lewis, Phys. Rev. Lett. 89, 255504(2002); [2] P. Lorazo, L. J. Lewis, and M. Meunier, Phys. Rev. Lett. 91, 225502 (2003).

  20. Fundamental Equation of State for Deuterium

    SciTech Connect

    Richardson, I. A.; Leachman, J. W.; Lemmon, E. W.

    2014-03-15

    World utilization of deuterium is anticipated to increase with the rise of fusion-energy machines such as ITER and NIF. We present a new fundamental equation of state for the thermodynamic properties of fluid deuterium. Differences between thermodynamic properties of orthodeuterium, normal deuterium, and paradeuterium are described. Separate ideal-gas functions were fitted for these separable forms together with a single real-fluid residual function. The equation of state is valid from the melting line to a maximum pressure of 2000 MPa and an upper temperature limit of 600 K, corresponding to available experimental measurements. The uncertainty in predicted density is 0.5% over the valid temperature range and pressures up to 300 MPa. The uncertainties of vapor pressures and saturated liquid densities are 2% and 3%, respectively, while speed-of-sound values are accurate to within 1% in the liquid phase.

  1. Deuterium Fractionation just after the Star Formation

    NASA Astrophysics Data System (ADS)

    Shibata, D.; Sakai, N.; Yamamoto, S.

    2013-10-01

    We have recently conducted a five-point strip observation of the DCO+, H13CO+, DNC, HN13C, and N2H+ lines toward low mass Class I protostar L1551 IRS5, and have evaluated the deuterium fractionation ratios DCO+/HCO+ and DNC/HNC. The DCO+/HCO+ ratio is found to be lower toward the protostar position than those toward the adjacent positions. On the other hand, the DNC/HNC ratio does not show such a decrease toward the protostar position. This suggests that the deuterium fractionation ratio of the neutral species is conserved after the star formation. If so, the deuterium fractionation of the neutral species can be used as a novel tracer to investigate the initial condition of the star formation process.

  2. Modeling target bulk heating resulting from ultra-intense short pulse laser irradiation of solid density targets

    SciTech Connect

    Antici, P.; Gremillet, L.; Grismayer, T.; Audebert, P.; Mančic, A.; Fuchs, J.; Borghesi, M.; Cecchetti, C. A.

    2013-12-15

    Isochoric heating of solid-density matter up to a few tens of eV is of interest for investigating astrophysical or inertial fusion scenarios. Such ultra-fast heating can be achieved via the energy deposition of short-pulse laser generated electrons. Here, we report on experimental measurements of this process by means of time- and space-resolved optical interferometry. Our results are found in reasonable agreement with a simple numerical model of fast electron-induced heating.

  3. Localized Hydration in Lyophilized Myoglobin by Hydrogen-Deuterium Exchange Mass Spectrometry. 2. Exchange Kinetics

    PubMed Central

    Sophocleous, Andreas M.; Topp, Elizabeth M.

    2012-01-01

    Solid-state hydrogen deuterium exchange with mass spectrometric analysis (ssHDX) is a promising method for characterizing proteins in amorphous solids. Though analysis of HDX kinetics is informative and well-established in solution, application of these methods to solid samples is complicated by possible heterogeneities in the solid. The studies reported here provide a detailed analysis of the kinetics of hydration and ssHDX for equine myoglobin (Mb) in solid matrices containing sucrose or mannitol. Water sorption was rapid relative to ssHDX, indicating that ssHDX kinetics was not limited by bulk water transport. Deuterium uptake in solids was well-characterized by a bi-exponential model; values for regression parameters provided insight into differences between the two solid matrices. Analysis of the widths of peptide mass envelopes revealed that in solution, an apparent EX2 mechanism prevails, consistent with native conformation of the protein. In contrast, in mannitol-containing samples, a smaller non-native subpopulation exchanges by an EX1-like mechanism. Together, the results indicate that the analysis of ssHDX kinetic data and the widths of peptide mass envelopes are useful in screening solid formulations of protein drugs for the presence of non-native species that cannot be detected by amide I FTIR. PMID:22352990

  4. Sustained molecular oxygen activation by solid iron doped silicon carbide under microwave irradiation: Mechanism and application to norfloxacin degradation.

    PubMed

    Li, Hongbo; Chen, Jing; Hou, Huijie; Pan, Hong; Ma, Xiaoxue; Yang, Jiakuan; Wang, Linling; Crittenden, John C

    2017-09-11

    Sustained molecular oxygen activation by iron doped silicon carbide (Fe/SiC) was investigated under microwave (MW) irradiation. The catalytic performance of Fe/SiC for norfloxacin (NOR) degradation was also studied. Rapid mineralization in neutral solution was observed with a pseudo-first-order rate constant of 0.2239 min(-1) under 540 W of MW irradiation for 20 min. Increasing Fe/SiC rod and MW power significantly enhanced the degradation and mineralization rate with higher yield of reactive oxygen species (ROS). Fe shell corrosion and subsequent Fe(0/II) oxidation by molecular oxygen with MW activation was the key factor for NOR degradation through two-electron-transfer by Fe(0) under acidic conditions and single-electron-transfer by Fe(II) under neutral-alkaline solution. Removal rate of NOR was significantly affected by solution pH, showing higher degradation rates at both acidic and alkaline conditions. The highest removal efficiencies and rates at alkaline pH values were ascribed to the contribution of bound Fe(II) species on the Fe shell surface due to the hydroxylation of Fe/SiC. ·OH was the main oxidizing specie for NOR degradation, confirmed by density functional theory (DFT) calculations and radical scavenger tests. DFT calculations were conducted on the reaction/activation energies of the transition/final states of NOR/degradation products, combined with intermediate identification with high performance liquid chromatography coupled with a triple-quadruple mass spectrometer (HPLC-MS/MS), the piperazinyl ring was the most reactive site for ·OH attack, followed by further ring-opening and stepwise oxidation. In this study, Fe/SiC were proved to be an excellent catalyst for the treatment of fluoroquinolone antibiotics with MW activation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Dynamics of deuterium turnover in the human body using 2(1)D(gamma, n) reaction.

    PubMed

    Malik, S R

    1987-01-01

    A rapid non-destructive and sensitive technique is used by which total body water and its rate of turnover (excretion) in human subjects can be easily measured. Subsequently, a simple calculation is made in estimating the total body fat and lean body mass. The measurements are, therefore, expected to shed useful light on the measurement technique as well as on the movement of body water in humans, and this will glean an understanding of physiological laws governing such movements. The method employs the activation of deuterium in water by bremsstrahlung radiations which are produced by stopping 3 MeV electrons in a gold target. The detection of photoneutrons, so obtained in the reaction 2(1)D(gamma, n), is accomplished by the capture of fission fragments in Solid State Nuclear Track Detector (SSNTD) issuing from the 235U(n, f) reaction. These fission events are then automatically counted by a spark counter. Thermal neutrons, required for the 235U fissioning, are obtained by employing a graphite moderator assembly at the core of which water and urine samples are being irradiated. The development of a few basic measurement parameters and their utilization in such measurements are also reported in the paper.

  6. Protective coatings preventing hydrogen desorption from titanium during ion irradiation

    NASA Astrophysics Data System (ADS)

    Evsin, A. E.; Begrambekov, L. B.; Dovganyuk, S. S.; Kaplevsky, A. S.; Shutikova, M. I.

    2017-05-01

    Effect of yttria and titanium nitride coatings on features of deuterium desorption from titanium layer is investigated. It is shown that both coatings significantly raise the temperature of maximum of deuterium thermal desorption from titanium under linear heating and prevent desorption under prolonged keeping at the operating temperature of a neutron tube target. However, under irradiation with ions of H2 + O2 plasma the barrier properties of titanium nitride appear to degrade.

  7. Highly efficient (19)F heteronuclear decoupling in solid-state NMR spectroscopy using supercycled refocused-CW irradiation.

    PubMed

    Equbal, Asif; Basse, Kristoffer; Nielsen, Niels Chr

    2016-12-07

    We present heteronuclear (19)F refocused CW (rCW) decoupling pulse sequences for solid-state magic-angle-spinning NMR applications. The decoupling sequences have been designed specifically to ensure suppression of the pertinent (13)C-(19)F dipolar coupling interactions while simultaneously suppressing strong anisotropic chemical shift as well as homonuclear (19)F-(19)F dipolar coupling effects as typically present in perfluorated compounds. In an extensive numerical and experimental analysis using a rigid, organic solid as a model compound, it becomes evident that the supercycled rCW schemes markedly improve the decoupling efficiency, leading to substantial enhancements in resolution and sensitivity when compared to previous state-of-the-art methods. Furthermore, considerable gains in robustness toward rf mismatch as well as offset in the radio-frequency carrier frequency are observed, all of which clearly render the new rCW schemes the methods of choice for (19)F decoupling in rigid, fluorinated compounds - which is further supported by a Floquet-based theoretical analysis.

  8. Microstructural studies of hydrogen and deuterium in bcc refractory metals

    SciTech Connect

    Moss, S.C.

    1980-01-01

    Over the past four years this research has been principally concerned with uncovering the microstructural atomic arrangements in alloys of hydrogen and deuterium with bcc refractory metals. Because these are interstitial phases in which the host metal lattice is substantially deformed by the incorporation of the H(D) atoms, there are pronounced x-ray scattering effects. X-ray diffraction has, therefore, been the main structural tool. A main objective of the project has been to determine the degree to which phase relations and solid solution properties in metal-hydride alloys depend upon the hydrogen-hydrogen interaction via the displacement field of the metal atoms. This has often included the elucidation of subtle thermodynamic properties which are revealed in structural studies.

  9. Preliminary ANS (Advanced Neutron Source) reactor cold source gain factor calculations for liquid deuterium and liquid nitrogen-15

    SciTech Connect

    Henderson, D.L.

    1988-11-01

    Individual energy group gain factors are computed for liquid nitrogen-15 and liquid deuterium cold source moderators using simple one-dimensional slab and spherical geometry calculational models. The energy spectrum of the neutron source is assumed to be that of a thermalized Maxwellian flux at 20/degree/C. The slab geometry calculations indicate that the optimum thickness for neutron transmission through a slab given an isotropic incident flux is for wavelengths above .6 nm, approximately .20 m for liquid deuterium and between .28 and .32 m for liquid nitrogen-15. The gain factors at .8 nm corresponding to these thicknesses are 15.5 for liquid deuterium and 3.50 for liquid nitrogen-15. The spherical geometry analysis showed that the cold neutron current below 10 MeV of 1.36 n/m/sup 2/-s for the neutron component entering the cavity of a .16 m thick liquid deuterium spherical shell exceeds the neutron leakage current of 1.08 n/cm/sup 2/-s from a .38 m diameter liquid deuterium solid sphere. However, the cold neutron factors for the neutron entering the void region are considerably lower than for the solid sphere case. 15 refs., 24 figs., 7 tabs.

  10. Solid-base loaded WO{sub 3} photocatalyst for decomposition of harmful organics under visible light irradiation

    SciTech Connect

    Kako, Tetsuya; Meng, Xianguang; Ye, Jinhua

    2015-10-01

    Composite of NaBiO{sub 3}-loaded WO{sub 3} with a mixing ratio of 10:100 was prepared for photocatalytic harmful-organic-contaminant decomposition. The composite properties were measured using X-ray diffraction, ultraviolet-visible spectrophotometer (UV-Vis), and valence band-X-ray photoelectron spectroscope (VB-XPS). The results exhibited that the potentials for top of the valence band and bottom of conduction band for NaBiO{sub 3} can be estimated, respectively, as +2.5 V and -0.1 to 0 V. Furthermore, WO{sub 3}, NaBiO{sub 3}, and the composite showed IPA oxidation properties under visible-light irradiation. Results show that the composite exhibited much higher photocatalytic activity about 2-propanol (IPA) decomposition into CO{sub 2} than individual WO{sub 3} or NaBiO{sub 3} because of charge separation promotion and the base effect of NaBiO{sub 3}.

  11. Repetitive Solid Spherical Pellet Injection and Irradiation toward the Repetitive-mode Fast-Ignition Fusion miniReactor CANDY.

    NASA Astrophysics Data System (ADS)

    HANAYAMA, Ryohei; KOMEDA, Osamu; NISHIMURA, Yasuhiko; MORI, Yoshitaka; ISHII, Katsuhiro; NAKAYAMA, Suisei; OKIHARA, Shinichiro; FUJITA, Kazuhisa; SEKINE, Takashi; SATO, Nakahiro; KURITA, Takashi; KAWASHIMA, Toshiyuki; KAN, Hirofumi; NAKAMURA, Naoki; KONDO, Takuya; FUJINE, Manabu; AZUMA, Hirozumi; HIOKI, Tatsumi; KAKENO, Mitsutaka; MOTOHIRO, Tomoyoshi; SUNAHARA, Atsushi; SENTOKU, Yasuhiko; MIURA, Eisuke; KITAGAWA, Yoneyoshi

    2016-03-01

    Pellet injection and repetitive laser illumination are key technologies for realizing inertial fusion energy[1-4]. Neutron generator using lasers also requires a repeating pellet target supplier. Here we present the first demonstration of target injection and neutron generation[5]. We injected more than 1300 spherical deuterated polystyrene(C8D8) bead pellet targets during 23 minutes at 1 Hz(Fig. 1). After the pellet targets fell for a distance of 18 cm, we applied the synchronized laser-diode-pumped ultra-intense laser HAMA. The laser intensity at the focal point is 5 x 1018 W/cm2, which is high enough to generate neutrons. As a result of the irradiation, we produced 2.45-MeV DD neutrons. Figure 2 shows the neutron time-of-flight signals detected by plastic scintillators coupled to photomultipliers. The neutron energy was calculated by the time-of-flight method. The maximum neutron yield was 9.5 x 104/4π sr. The result is a step toward fusion power and also suggests possible industrial neutron sources.

  12. The deuterium puzzle in the symmetric universe

    NASA Technical Reports Server (NTRS)

    Leroy, B.; Nicolle, J. P.; Schatzman, E.

    1973-01-01

    An attempt was made to use deuterium abundance in the symmetric universe to prove that no nucleosynthesis takes place during annihilation and therefore neutrons were loss before nucleosynthesis. Data cover nucleosynthesis during the radiative era, cross section estimates, maximum abundance of He-4 at the end of nucleosynthesis area, and loss rate.

  13. Deuterium fractionation in the Ophiuchus molecular cloud

    NASA Astrophysics Data System (ADS)

    Punanova, A.; Caselli, P.; Pon, A.; Belloche, A.; André, Ph.

    2016-03-01

    Context. In cold (T< 25 K) and dense (nH> 104 cm-3) interstellar clouds, molecules such as CO are significantly frozen onto dust grain surfaces. Deuterium fractionation is known to be very efficient in these conditions as CO limits the abundance of H3+, which is the starting point of deuterium chemistry. In particular, N2D+ is an excellent tracer of dense and cold gas in star-forming regions. Aims: We measure the deuterium fraction, RD, and the CO depletion factor, fd, towards a number of starless and protostellar cores in the L1688 region of the Ophiuchus molecular cloud complex and search for variations based upon environmental differences across L1688. The kinematic properties of the dense gas traced by the N2H+ and N2D+ (1-0) lines are also discussed. Methods: Deuterium fraction has been measured via observations of the J = 1-0 transition of N2H+ and N2D+ towards 33 dense cores in different regions of L1688. We estimated the CO depletion factor using C17O(1-0) and 850 μm dust continuum emission from the SCUBA survey. We carried out all line observations with the IRAM 30 m antenna. Results: The dense cores show large (≃2-40%) deuterium fractions with significant variations between the sub-regions of L1688. The CO depletion factor also varies from one region to another (between ≃1 and 7). Two different correlations are found between deuterium fraction and CO depletion factor: cores in regions A, B2, and I show increasing RD with increasing fd, similar to previous studies of deuterium fraction in pre-stellar cores; cores in regions B1, B1B2, C, E, F, and H show a steeper RD - fd correlation with large deuterium fractions occurring in fairly quiescent gas with relatively low CO freeze-out factors. These are probably recently formed, centrally concentrated starless cores, which have not yet started the contraction phase towards protostellar formation. We also find that the deuterium fraction is affected by the amount of turbulence, dust temperature, and

  14. Experimental Investigation of Irradiation-driven Hydrogen Isotope Fractionation in Analogs of Protoplanetary Hydrous Silicate Dust

    NASA Astrophysics Data System (ADS)

    Roskosz, Mathieu; Laurent, Boris; Leroux, Hugues; Remusat, Laurent

    2016-11-01

    The origin of hydrogen in chondritic components is poorly understood. Their isotopic composition is heavier than the solar nebula gas. In addition, in most meteorites, hydrous silicates are found to be lighter than the coexisting organic matter. Ionizing irradiation recently emerged as an efficient hydrogen fractionating process in organics, but its effect on H-bearing silicates remains essentially unknown. We report the evolution of the D/H of hydrous silicates experimentally irradiated by electrons. Thin films of amorphous silica, amorphous “serpentine,” and pellets of crystalline muscovite were irradiated at 4 and 30 keV. For all samples, irradiation leads to a large hydrogen loss correlated with a moderate deuterium enrichment of the solid residue. The entire data set can be described by a Rayleigh distillation. The calculated fractionation factor is consistent with a kinetically controlled fractionation during the loss of hydrogen. Furthermore, for a given ionizing condition, the deuteration of the silicate residues is much lower than the deuteration measured on irradiated organic macromolecules. These results provide firm evidence of the limitations of ionizing irradiation as a driving mechanism for D-enrichment of silicate materials. The isotopic composition of the silicate dust cannot rise from a protosolar to a chondritic signature during solar irradiations. More importantly, these results imply that irradiation of the disk naturally induces a strong decoupling of the isotopic signatures of coexisting organics and silicates. This decoupling is consistent with the systematic difference observed between the heavy organic matter and the lighter water typically associated with minerals in the matrix of most carbonaceous chondrites.

  15. Plume segregation observed in hydrogen and deuterium containing plasmas produced by laser ablation of carbon fiber tiles from a fusion reactor

    NASA Astrophysics Data System (ADS)

    Mercadier, L.; Hermann, J.; Grisolia, C.; Semerok, A.

    2010-08-01

    The plasma produced by the irradiation of a hydrogen and deuterium containing carbon fiber composite with infrared laser pulses of 4-ns pulse duration has been investigated. The experiments were carried out under argon at reduced pressure. Microscopic analyses of the irradiated sample surface were performed to measure the ablation depth. Time- and space-resolved optical emission spectroscopy was applied to characterize the evolution of spectral line emission as a function of time and distance from the surface. Particular attention was paid to the time-of-flight characteristics of the hydrogen and deuterium Balmer α spectral lines. According to the different atomic masses of both isotopes, the expansion of hydrogen into the low pressure argon atmosphere was found to be slightly faster than that of deuterium. The effect of plume segregation is pressure dependent and tends to increase the analytical signal of heavy atoms with respect to lighter ones during laser-induced breakdown spectroscopy.

  16. Nuclear spin polarization of solid deuterium-tritium

    SciTech Connect

    Souers, P.C.; Fearon, E.M.; Mapoles, E.R.; Gaines, J.R.; Sater, J.D.; Fedders, P.A.

    1985-01-01

    It appears that parallel alignment of deuteron and triton magnetic moments increases the cross section of the nuclear reaction T(d,n) He/sup 4/ by 50%, thereby promising a laser driver of perhaps half the original energy. Both ''brute-force'' and dynamic nuclear polarization are considered, and the many potential problems of the latter are considered. High nuclear polarization by the dynamic technique requires a small nucleus-to-unpaired electron ratio, a long longitudinal nuclear relaxation time and a short longitudinal electron relaxation time. Normal D-T is shown to be inadequate, and enriched and possibly very pure molecular DT will be required. The key variable is the nuclear relaxation time, which can either depend on the interaction with rotationally excited impurity molecules or on paramagnetic defects formed by the tritium radiation. Radiation-induced DT decomposition and rotational catalysis will combat one another to affect the DT purity. The expected atom density and fractionation effects are considered. There exists one frequency at which both D and T atoms can be pumped.

  17. Nuclear spin polarization of solid deuterium-tritium. Revision 1

    SciTech Connect

    Souers, P.C.; Fearon, E.M.; Mapoles, E.R.; Gaines, J.R.; Sater, J.D.; Fedders, P.A.

    1985-01-01

    It appears that parallel alignment of deuteron and triton magnetic moments increases the cross section of the nuclear reaction T(d,n) He/sup 4/ by 50%, thereby promising a laser driver of perhaps half the original energy. Both ''brute-force'' and dynamic nuclear polarization are considered, and the many potential problems of the latter are considered. High nuclear polarization by the dynamic technique requires a small nucleus-to-unpaired electron ratio, a long longitudinal nuclear relaxation time and a short longitudinal electron relaxation time. Normal D-T is shown to be inadequate, and enriched and possibly very pure molecular DT will be required. The key variable is the nuclear relaxation time, which can either depend on the interaction with rotationally excited impurity molecules or on paramagnetic defects formed by the tritium radiation. Radiation-induced DT decomposition and rotational catalysis will combat one another to affect the DT purity. The expected atom density and fractionation effects are considered. There exists one frequency at which both D and T atoms can be pumped.

  18. Cosmic Deuterium and Social Networking Software

    NASA Astrophysics Data System (ADS)

    Pasachoff, J. M.; Suer, T.-A.; Lubowich, D. A.; Glaisyer, T.

    2006-08-01

    For the education of newcomers to a scientific field and for the convenience of students and workers in the field, it is helpful to have all the basic scientific papers gathered. For the study of deuterium in the Universe, in 2004-5 we set up http://www.cosmicdeuterium.info with clickable links to all the historic and basic papers in the field and to many of the current papers. Cosmic deuterium is especially important because all deuterium in the Universe was formed in the epoch of nucleosynthesis in the first 1000 seconds after the Big Bang, so study of its relative abundance (D:H~1:100,000) gives us information about those first minutes of the Universe's life. Thus the understanding of cosmic deuterium is one of the pillars of modern cosmology, joining the cosmic expansion, the 3 degree cosmic background radiation, and the ripples in that background radiation. Studies of deuterium are also important for understanding Galactic chemical evolution, astrochemistry, interstellar processes, and planetary formation. Some papers had to be scanned while others are available at the Astrophysical Data System, adswww.harvard.edu, or to publishers' Websites. By 2006, social networking software (http:tinyurl.com/ zx5hk) had advanced with popular sites like facebook.com and MySpace.com; the Astrophysical Data System had even set up MyADS. Social tagging software sites like http://del.icio.us have made it easy to share sets of links to papers already available online. We have set up http://del.icio.us/deuterium to provide links to many of the papers on cosmicdeuterium.info, furthering previous del.icio.us work on /eclipses and /plutocharon. It is easy for the site owner to add links to a del.icio.us site; it takes merely clicking on a button on the browser screen once the site is opened and the desired link is viewed in a browser. Categorizing different topics by keywords allows subsets to be easily displayed. The opportunity to expose knowledge and build an ecosystem of web

  19. High e+/e– ratio dense pair creation with 1021W.cm–2 laser irradiating solid targets

    SciTech Connect

    Liang, E.; Clarke, T.; Henderson, A.; Fu, W.; Lo, W.; Taylor, D.; Chaguine, P.; Zhou, S.; Hua, Y.; Cen, X.; Wang, X.; Kao, J.; Hasson, H.; Dyer, G.; Serratto, K.; Riley, N.; Donovan, M.; Ditmire, T.

    2015-09-14

    In this study, we report results of new pair creation experiments using ~100 Joule pulses of the Texas Petawatt Laser to irradiate solid gold and platinum targets, with intensities up to ~1.9 × 1021 W.cm–2 and pulse durations as short as ~130 fs. Positron to electron (e+/e–) ratios >15% were observed for many thick disk and rod targets, with the highest e+/e– ratio reaching ~50% for a Pt rod. The inferred pair yield was ~ few ×1010 with emerging pair density reaching ~1015/cm3 so that the pair skin depth becomes < pair jet transverse size. These results represent major milestones towards the goal of creating a significant quantity of dense pair-dominated plasmas with e+/e– approaching 100% and pair skin depth << pair plasma size, which will have wide-ranging applications to astrophysics and fundamental physics.

  20. Separation of (44)Ti from proton irradiated scandium by using solid-phase extraction chromatography and design of (44)Ti/(44)Sc generator system.

    PubMed

    Radchenko, V; Meyer, C A L; Engle, J W; Naranjo, C M; Unc, G A; Mastren, T; Brugh, M; Birnbaum, E R; John, K D; Nortier, F M; Fassbender, M E

    2016-12-16

    Scandium-44g (half-life 3.97h [1]) shows promise for positron emission tomography (PET) imaging of longer biological processes than that of the current gold standard, (18)F, due to its favorable decay parameters. One source of (44g)Sc is the long-lived parent nuclide (44)Ti (half-life 60.0 a). A (44)Ti/(44g)Sc generator would have the ability to provide radionuclidically pure (44g)Sc on a daily basis. The production of (44)Ti via the (45)Sc(p,2n) reaction requires high proton beam currents and long irradiation times. Recovery and purification of no-carrier added (nca) (44)Ti from scandium metal targets involves complex separation chemistry. In this study, separation systems based on solid phase extraction chromatography were investigated, including branched diglycolamide (BDGA) resin and hydroxamate based ZR resin. Results indicate that ZR resin in HCl media represents an effective (44)Ti/(44g)Sc separation system. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Magic angle Lee-Goldburg frequency offset irradiation improves the efficiency and selectivity of SPECIFIC-CP in triple-resonance MAS solid-state NMR

    NASA Astrophysics Data System (ADS)

    Wu, Chin H.; De Angelis, Anna A.; Opella, Stanley J.

    2014-09-01

    The efficiency and selectivity of SPECIFIC-CP, a widely used method for selective double cross-polarization in triple-resonance magic angle spinning solid-state NMR, is improved by performing the tangential-shaped 13C irradiation at an offset frequency that meets the Lee-Goldburg condition (LG-SPECIFIC-CP). This is demonstrated on polycrystalline samples of uniformly 13C, 15N labeled N-acetyl-leucine and N-formyl-Met-Leu-Phe-OH (MLF) at 700 MHz and 900 MHz 1H resonance frequencies, respectively. For the single 13Cα of N-acetyl-leucine, relative to conventional broad band cross-polarization, the SPECIFIC-CP signal has 47% of the intensity. Notably, the LG-SPECIFIC-CP signal has 72% of the intensity, essentially the theoretical maximum. There were no other changes in the experimental parameters. The three 13Cα signals in MLF show some variation in intensities, reflecting the relatively narrow bandwidth of a frequency-offset procedure, and pointing to future developments for this class of experiment.

  2. Identification of halogenated photoproducts generated after ultraviolet-irradiation of parabens and benzoates in water containing chlorine by solid-phase microextraction and gas chromatography-mass spectrometry.

    PubMed

    Alvarez-Rivera, Gerardo; Llompart, Maria; Garcia-Jares, Carmen; Lores, Marta

    2014-07-04

    This work presents a new solid-phase microextraction (SPME)-based approach to investigate the formation of halogenated by-products generated by the UV-induced photodegradation of parabens and their congener benzoates in water containing chlorine. Degradation of parent species, and further identification of their transformation by-products were monitored by gas chromatography coupled to mass spectrometry (GC/MS). In order to improve detectability, SPME was applied as a preconcentration step after UV-irradiation of target preservatives. Experiments performed with dechlorinated water, ultrapure water, and tap water showed that under UV-light, the presence of even low levels of free chlorine, increases the photodegradation rate of target preservatives, enhancing the formation of halogenated photoproducts. Monobrominated, dibrominated and bromochlorinated hydroxybenzoates were identified, and the transformation of benzoates into halogenated parabens was also confirmed. Bromination is expected to occur when free chlorine is present, due to the presence of traces of bromide in water samples. Five halogenated phenols (mainly brominated) were detected as breakdown photoproducts from both families of target preservatives. On the basis of the appearance of the aforementioned by-products, a tentative transformation pathway, consistent with the photoformation-photodecay kinetics of the by-products, is proposed herein for the first time.

  3. Self-irradiation effect on thermal conductivity of Zr0.70Pu0.25Cm0.05N solid solution

    NASA Astrophysics Data System (ADS)

    Nishi, Tsuyoshi; Hayashi, Hirokazu; Sato, Takumi; Takano, Masahide

    2017-04-01

    This study evaluated the dependence of the thermal conductivity of Zr0.70Pu0.25Cm0.05N on storage time and temperature. The authors prepared sintered samples of Zr0.70Pu0.25Cm0.05N solid solution and measured thermal diffusivity at storage times of 0, 24, 72, 144, 240, 408, 552, 816, 1,680, and 2064 h, from which it was determined that the thermal conductivity decreased exponentially with increasing storage time. This result suggests that the decrease of the thermal conductivity could be attributed to the accumulation of lattice defects from self-irradiation. To confirm the thermal recovery behavior of Zr0.70Pu0.25Cm0.05N under annealing, thermal diffusivity was also measured just after annealing. The thermal conductivity of Zr0.70Pu0.25Cm0.05N was determined to be larger than that of Zr0.58Pu0.21Cm0.21N but smaller than that of Zr0.80Pu0.10Cm0.10N.

  4. Magic angle Lee-Goldburg frequency offset irradiation improves the efficiency and selectivity of SPECIFIC-CP in triple-resonance MAS solid-state NMR

    PubMed Central

    Wu, C.H.; De Angelis, Anna A.; Opella, Stanley J.

    2014-01-01

    The efficiency and selectivity of SPECIFIC-CP, a widely used method for selective double cross-polarization in triple-resonance magic angle spinning solid-state NMR, is improved by performing the tangential-shaped 13C irradiation at an offset frequency that meets the Lee-Goldburg condition (LG-SPECIFIC-CP). This is demonstrated on polycrystalline samples of uniformly 13C, 15N labeled N-acetyl-leucine and N-formyl-Met-Leu-Phe-OH (MLF) at 700 MHz and 900 MHz 1H resonance frequencies, respectively. For the single 13Cα of N-acetyl-leucine, relative to conventional broad band cross-polarization, the SPECIFIC-CP signal has 47% of the intensity. Notably, the LG-SPECIFIC-CP signal has 72% of the intensity, essentially the theoretical maximum. There were no other changes in the experimental parameters. The three 13Cα signals in MLF show some variation in intensities, reflecting the relatively narrow bandwidth of a frequency-offset procedure, and pointing to future developments for this class of experiment. PMID:25051542

  5. Separation of 44Ti from proton irradiated scandium by using solid-phase extraction chromatography and design of 44Ti/44Sc generator system

    DOE PAGES

    Radchenko, Valery; Meyer, Catherine Anne Louise; Engle, Jonathan Ward; ...

    2016-11-24

    Scandium-44 g (half-life 3.97 h) shows promise for positron emission tomography (PET) imaging of longer biological processes than that of the current gold standard, 18F, due to its favorable decay parameters. One source of 44gSc is the long-lived parent nuclide 44Ti (half-life 60.0 a). A 44Ti/44gSc generator would have the ability to provide radionuclidically pure 44gSc on a daily basis. The production of 44Ti via the 45Sc(p,2n) reaction requires high proton beam currents and long irradiation times. Recovery and purification of no-carrier added (nca) 44Ti from scandium metal targets involves complex separation chemistry. In this study, separation systems based onmore » solid phase extraction chromatography were investigated, including branched diglycolamide (BDGA) resin and hydroxamate based ZR resin. Lastly, results indicate that ZR resin in HCl media represents an effective 44Ti/44gSc separation system.« less

  6. Irradiation of Ethylene Diluted in Solid Nitrogen with Vacuum Ultraviolet Light and Electrons: Its Implications for the Formation of HCN and HNC

    NASA Astrophysics Data System (ADS)

    Chen, Hui-Fen; Liu, Meng-Chen; Chen, Sian-Cong; Huang, Tzu-Ping; Wu, Yu-Jong

    2015-05-01

    Chemical reactions of C2H4 dispersed in solid nitrogen at 10 K that occur upon irradiation with Lyα light at a wavelength of 121.6 nm and 500 eV electrons were investigated by measuring the infrared absorption spectra. Photolysis of the matrix samples with 121.6 nm light yielded products, including C2H2, CN, and isomers of C2N2, as well as a pair of HCN and HNC. In contrast, electron bombardment of similar matrix samples mainly resulted in the generation of N3, C2H2, C2H3, C3H2, and C3N-. Mechanisms of the reactions that occur during the photolysis and electron-radiation of the matrix samples are discussed. The results of the study provide insights into the formation of HNC and HCN, as well as nitriles, in N2-rich ice samples containing a small proportion of C2H4.

  7. IRRADIATION OF ETHYLENE DILUTED IN SOLID NITROGEN WITH VACUUM ULTRAVIOLET LIGHT AND ELECTRONS: ITS IMPLICATIONS FOR THE FORMATION OF HCN AND HNC

    SciTech Connect

    Chen, Hui-Fen; Liu, Meng-Chen; Chen, Sian-Cong; Huang, Tzu-Ping; Wu, Yu-Jong

    2015-05-01

    Chemical reactions of C{sub 2}H{sub 4} dispersed in solid nitrogen at 10 K that occur upon irradiation with Lyα light at a wavelength of 121.6 nm and 500 eV electrons were investigated by measuring the infrared absorption spectra. Photolysis of the matrix samples with 121.6 nm light yielded products, including C{sub 2}H{sub 2}, CN, and isomers of C{sub 2}N{sub 2}, as well as a pair of HCN and HNC. In contrast, electron bombardment of similar matrix samples mainly resulted in the generation of N{sub 3}, C{sub 2}H{sub 2}, C{sub 2}H{sub 3}, C{sub 3}H{sub 2}, and C{sub 3}N{sup −}. Mechanisms of the reactions that occur during the photolysis and electron-radiation of the matrix samples are discussed. The results of the study provide insights into the formation of HNC and HCN, as well as nitriles, in N{sub 2}-rich ice samples containing a small proportion of C{sub 2}H{sub 4}.

  8. Study of a solid state microdosemeter based on a monolithic silicon telescope: irradiations with low-energy neutrons and direct comparison with a cylindrical TEPC.

    PubMed

    Agosteo, S; Colautti, P; Fanton, I; Fazzi, A; Introini, M V; Moro, D; Pola, A; Varoli, V

    2011-02-01

    A silicon device based on the monolithic silicon telescope technology coupled to a tissue-equivalent converter was proposed and investigated for solid state microdosimetry. The detector is constituted by a ΔE stage about 2 µm in thickness geometrically segmented in a matrix of micrometric diodes and a residual-energy measurement stage E about 500 µm in thickness. Each thin diode has a cylindrical sensitive volume 9 µm in nominal diameter, similar to that of a cylindrical tissue-equivalent proportional counter (TEPC). The silicon device and a cylindrical TEPC were irradiated in the same experimental conditions with quasi-monoenergetic neutrons of energy between 0.64 and 2.3 MeV at the INFN-Legnaro National Laboratories (LNL-INFN, Legnaro, Italy). The aim was to study the capability of the silicon-based system of reproducing microdosimetric spectra similar to those measured by a reference microdosemeter. The TEPC was set in order to simulate a tissue site about 2 μm in diameter. The spectra of the energy imparted to the ▵E stage of the silicon telescope were corrected for tissue-equivalence through an optimized procedure that exploits the information from the residual energy measurement stage E. A geometrical correction based on parametric criteria for shape-equivalence was also applied. The agreement between the dose distributions of lineal energy and the corresponding mean values is satisfactory at each neutron energy considered.

  9. Magic angle Lee-Goldburg frequency offset irradiation improves the efficiency and selectivity of SPECIFIC-CP in triple-resonance MAS solid-state NMR.

    PubMed

    Wu, Chin H; De Angelis, Anna A; Opella, Stanley J

    2014-09-01

    The efficiency and selectivity of SPECIFIC-CP, a widely used method for selective double cross-polarization in triple-resonance magic angle spinning solid-state NMR, is improved by performing the tangential-shaped (13)C irradiation at an offset frequency that meets the Lee-Goldburg condition (LG-SPECIFIC-CP). This is demonstrated on polycrystalline samples of uniformly (13)C, (15)N labeled N-acetyl-leucine and N-formyl-Met-Leu-Phe-OH (MLF) at 700MHz and 900MHz (1)H resonance frequencies, respectively. For the single (13)Cα of N-acetyl-leucine, relative to conventional broad band cross-polarization, the SPECIFIC-CP signal has 47% of the intensity. Notably, the LG-SPECIFIC-CP signal has 72% of the intensity, essentially the theoretical maximum. There were no other changes in the experimental parameters. The three (13)Cα signals in MLF show some variation in intensities, reflecting the relatively narrow bandwidth of a frequency-offset procedure, and pointing to future developments for this class of experiment. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. GROWTH OF AZOTOBACTER IN DEUTERIUM OXIDE

    PubMed Central

    Johnstone, D. B.

    1962-01-01

    Johnstone, D. B. (University of Vermont, Burlington). Growth of Azotobacter in deuterium oxide. J. Bacteriol. 83:867–870. 1962.—To the small list of bacteria that are reported to have been cultured in fully deuterated media can be added Azotobacter agilis and A. vinelandii. Moreover, these bacteria, although growing in a deuterium oxide medium with deuterated carbon sources, will fix atmospheric nitrogen. Lag periods occur prior to growth, and wide morphological variation is apparent during adaptation to a deuterated environment. A convenient method is presented for measuring, by infrared spectroscopy, the amount of water that accumulates in a D2O medium; during incubation this amounts to about 1% per day. Prevention of this accumulation of water indicates that growth, after a lag period, probably is not supported by accumulated hydrogen. PMID:14452164

  11. Deuterium content of the Venus atmosphere

    NASA Technical Reports Server (NTRS)

    Bertaux, Jean-Loup; Clarke, John T.

    1989-01-01

    The abundance of deuterium in the atmosphere of Venus is an important clue to the role of water in the planet's history, because ordinary and deuterated water escape the atmosphere at different rates. The high-resolution mode of the IUE was used to measure hydrogen Lyman-alpha emission from Venus, but only an upper limit on deuterium Lyman-alpha emission was found, from which was inferred a D/H ratio of less than 0.002-0.005. This is smaller by a factor of 3-8 than the D/H ratio derived from measurements by the Pioneer Venus Large Probe, and may indicate either a stratification of D/H ratio with altitude or a smaller overall ratio than previously thought.

  12. Deuterium Abundance in the Local Interstellar Medium

    NASA Technical Reports Server (NTRS)

    Ferlet, R.; Gry, C.; Vidal-Madjar, A.

    1984-01-01

    The present situation of deuterium abundance evaluation in interstellar space is discussed, and it is shown that it should be or = .00001 by studying in more detail lambda the Sco line of sight and by observing two NaI interstellar components toward that star, it can be shown that the D/H evaluation made toward lambda Sco is in fact related to the local interstellar medium (less than 10 pc from the Sun). Because this evaluation is also or = .00001 it is in striking contrast with the one made toward alpha Aur (D/H or = .000018 confirming the fact that the deuterium abundance in the local interstellar medium varies by at least a factor of two over few parsecs.

  13. Formation and retention of organically bound deuterium in rice in deuterium water release experiment.

    PubMed

    Atarashi-Andoh, Mariko; Amano, Hikaru; Kakiuchi, Hideki; Ichimasa, Michiko; Ichimasa, Yusuke

    2002-06-01

    As a substitute of tritium, deuterated water (D2O) vapor release experiments were performed in a greenhouse to estimate the different formation and subsequent retention of organically bound deuterium in rice plants between daytime and nighttime exposure. Potted rice plants were exposed to D2O vapor in the greenhouse for 8 h, under day or night conditions. Deuterium concentrations in free water and organic matter in rice leaves and ears were investigated until harvest time. The formation of organically bound deuterium in the daytime was higher than during the nighttime by the factors of 2.4 for the ear and 2.9 for the leaf. The decrease of the organically bound deuterium concentration in the ear after the nighttime exposure was faster than that after the daytime exposure. Data analysis was carried out using a compartment model in which different generating processes of organic matter were considered. The calculated organically bound deuterium retention in rice agreed with the measured value.

  14. Applications of deuterium oxide in human health.

    PubMed

    Bila, Wendell Costa; Mariano, Reysla Maria da Silveira; Silva, Valmin Ramos; Santos, Maria Emília Soares Martins Dos; Lamounier, Joel Alves; Ferriolli, Eduardo; Galdino, Alexsandro Sobreira

    2017-02-06

    The main aim goal of this review was to gather information about recent publications related to deuterium oxide (D2O), and its use as a scientific tool related to human health. Searches were made in electronic databases Pubmed, Scielo, Lilacs, Medline and Cochrane. Moreover, the following patent databases were consulted: EPO (Espacenet patent search), USPTO (United States Patent and Trademark Office) and Google Patents, which cover researches worldwide related to innovations using D2O.

  15. Central Greenland Holocene Deuterium Excess Variability

    NASA Astrophysics Data System (ADS)

    Masson-Delmotte, V.; Jouzel, J.; Falourd, S.; Cattani, O.; Dahl-Jensen, D.; Johnsen, S.; Sveinbjornsdottir, A. E.; White, J. W. C.

    Water stable isotopes (oxygen 18 and deuterium) have been measured along the Holocene part of two deep ice cores from central Greenland, GRIP and North GRIP. Theoretical studies have shown that the second-order isotopic parameter, the deu- terium excess (d=dD-8d18O), is an indicator of climatic changes at the oceanic mois- ture source reflecting at least partly changes in sea-surface-temperature. The two deu- terium excess records from GRIP and North GRIP show a long term increasing trend already observed in Antarctic deep ice cores and related to changes in the Earth's obliquity during the Holocene : an decreased obliquity is associated with a larger low to high latitude annual mean insolation gradient, warmer tropics, colder poles, and a more intense atmospheric transport from the tropics to the poles, resulting in a higher moisture source temperature and higher deuterium excess values. Superimposed onto this long term trend, central Greenland deuterium excess records also exhibit small abrupt events (8.2 ka BP and 4.5 ka BP) and a high frequency variability.

  16. Is Deuterium Nuclear Fusion Catalyzed by Antineutrinos?

    NASA Astrophysics Data System (ADS)

    Shomer, Isaac

    2010-02-01

    The hypothesis of Fischbach and Jenkins that neutrinos emitted from the sun accelerate radioactive decay is noted. It is thought that neutrinos accelerate beta decay by reacting with neutron-rich nuclides to form a beta particle and a daughter product, with no antineutrino emitted. Conversely, it is proposed that antineutrinos can react with proton-rich nuclides to cause positron decay, with no neutrino emitted. It is also proposed that the nuclear fusion of the hydrogen bomb is triggered not only by the energy of the igniting fission bomb, but by the antineutrinos created by the rapid beta decay of the daughter products in the fission process. The contemplated mechanism for antineutrino initiated fusion is the following: 1. The antineutrinos from the fission daughter products cause positron decay of deuterium by the process outlined above. 2. In a later fusion step, these positrons subsequently react with neutrons in deuterium to create antineutrinos. Electrons are unavailable to annihilate positrons in the plasma of the hydrogen bomb. 3. These antineutrinos thereafter react with more deuterium to form positrons, thereby propagating a chain reaction. )

  17. Deuterium quantification through deuterium-induced remote 1H and 13C NMR shifts.

    PubMed

    Knorr, Rudolf; Stephenson, David S

    2012-06-11

    Partial labeling by deuterium may be quantified through simple integrations of those (1)H (200 or 400 MHz) and (13)C (100.6 MHz) NMR resonances that are split into pairs by chemical shifts (n)Δ = δ(deuterated) - δ(nondeuterated) as induced by deuterium across n>2 chemical bonds. The relative intensities of the two components of a pair are shown to be influenced to practically equal degrees by relaxation effects, so that a deuterium fraction may be determined from (1)H and (13)C integral pairs at more remote molecular positions under the routine conditions of fast accumulative spectral acquisition. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. High-Dose Chemotherapy, Total-Body Irradiation, and Autologous Stem Cell Transplantation or Bone Marrow Transplantation in Treating Patients With Hematologic Cancer or Solid Tumors

    ClinicalTrials.gov

    2013-05-07

    Breast Cancer; Leukemia; Lymphoma; Multiple Myeloma and Plasma Cell Neoplasm; Testicular Germ Cell Tumor; Unspecified Adult Solid Tumor, Protocol Specific; Unspecified Childhood Solid Tumor, Protocol Specific

  19. Deuterium nuclear magnetic resonance study of amino acid dynamics in the membrane protein, bacteriorhodopsin

    SciTech Connect

    Smith, R.L.

    1984-01-01

    Deuterium (/sup 2/H) Fourier transform nuclear magnetic resonance (NMR) spectra for many polycrystalline, deuterium-labelled amino acids in the solid state have been obtained. Where possible, these have been biosynthetically incorporated into the membrane protein, bacteriorhodopsin in the photosynthetic purple membrane of Halobacterium halobium. Deuterio-methyl group spin lattice relaxation times have been obtained as a function of temperature. The results yield the Arrhenius activation energies for methyl rotation, and through the use of a suitable mathematical model, rotation correlation time. The results are analyzed using a mathematical model for two-fold flipping about the C/sub 2/ axis. Overall, the results demonstrate a similarity between the dynamics in amino acid crystals and in membrane proteins.

  20. Evolution of dispersion in the cosmic deuterium abundance

    NASA Astrophysics Data System (ADS)

    Dvorkin, Irina; Vangioni, Elisabeth; Silk, Joseph; Petitjean, Patrick; Olive, Keith A.

    2016-05-01

    Deuterium is created during big bang nucleosynthesis, and, in contrast to the other light stable nuclei, can only be destroyed thereafter by fusion in stellar interiors. In this Letter, we study the cosmic evolution of the deuterium abundance in the interstellar medium (ISM) and its dispersion using realistic galaxy evolution models. We find that models that reproduce the observed metal abundance are compatible with observations of the deuterium abundance in the local ISM and z ˜ 3 absorption line systems. In particular, we reproduce the low astration factor which we attribute to a low global star formation efficiency. We calculate the dispersion in deuterium abundance arising from different structure formation histories in different parts of the Universe. Our model also predicts a tight correlation between deuterium and metal abundances which could be used to measure the primordial deuterium abundance.

  1. Deuterium incorporation in biomass cell wall components by NMR analysis

    SciTech Connect

    Foston, Marcus B; McGaughey, Joseph; O'Neill, Hugh Michael; Evans, Barbara R; Ragauskas, Arthur J

    2012-01-01

    A commercially available deuterated kale sample was analyzed for deuterium incorporation by ionic liquid solution 2H and 1H nuclear magnetic resonance (NMR). This protocol was found to effectively measure the percent deuterium incorporation at 33%, comparable to the 31% value determined by combustion. The solution NMR technique also suggested by a qualitative analysis that deuterium is preferentially incorporated into the carbohydrate components of the kale sample.

  2. Mechanisms of H{sub 2}O desorption from amorphous solid water by 157-nm irradiation: An experimental and theoretical study

    SciTech Connect

    DeSimone, Alice J.; Crowell, Vernon D.; Sherrill, C. David; Orlando, Thomas M.

    2013-10-28

    The photodesorption of water molecules from amorphous solid water (ASW) by 157-nm irradiation has been examined using resonance-enhanced multiphoton ionization. The rotational temperature has been determined, by comparison with simulations, to be 425 ± 75 K. The time-of-flight spectrum of H{sub 2}O (v= 0) has been fit with a Maxwell-Boltzmann distribution with a translational temperature of 700 ± 200 K (0.12 ± 0.03 eV). H{sup +} and OH{sup +} fragment ions have been detected with non-resonant multiphoton ionization, indicating vibrationally excited parent water molecules with translational energies of 0.24 ± 0.08 eV. The cross section for water removal from ASW by 7.9-eV photons near 100 K is (6.9 ± 1.8) × 10{sup −20} cm{sup 2} for >10 L H{sub 2}O exposure. Electronic structure computations have also probed the excited states of water and the mechanisms of desorption. Calculated electron attachment and detachment densities show that exciton delocalization leads to a dipole reversal state in the first singlet excited state of a model system of hexagonal water ice. Ab Initio Molecular Dynamics simulations show possible desorption of a photo-excited water molecule from this cluster, though the non-hydrogen bonded OH bond is stretched significantly before desorption. Potential energy curves of this OH stretch in the electronic excited state show a barrier to dissociation, lending credence to the dipole reversal mechanism.

  3. Surface chemistry and physics of deuterium retention in lithiated graphite

    SciTech Connect

    Taylor, C. N.; Krstic, Predrag S; Allain, J. P.; Heim, B.; Skinner, C. H.; Kugel, H.

    2011-01-01

    Lithium wall conditioning in TFTR, CDX-U, T-11M, TJ-II and NSTX is found to yield enhanced plasma performance manifest, in part, through improved deuterium particle control. X-ray photoelectron spectroscopy (XPS) experiments examine the affect of D irradiation on lithiated graphite and show that the surface chemistry of lithiated graphite after D ion bombardment (500 eV/amu) is fundamentally different from that of non-Li conditioned graphite. Instead of simple LiD bonding seen in pure liquid Li, graphite introduces additional complexities. XPS spectra show that Li-O-D (533.0 {+-} 0.6 eV) and Li-C-D (291.4 {+-} 0.6 eV) bonds, for a nominal Li dose of 2 {micro}m, become 'saturated' with D at fluences between 3.8 and 5.2 x 10{sup 17} cm{sup -2}. Atomistic modeling indicate that Li-O-D-C interactions may be a result of multibody effects as opposed to molecular bonding.

  4. Note: Infrared laser diagnostics for deuterium gas puff Z pinches

    NASA Astrophysics Data System (ADS)

    Ivanov, V. V.; McKee, E. S.; Hammel, B. D.; Darling, T. W.; Swanson, K. J.; Covington, A. M.

    2017-07-01

    Deuterium gas puff Z pinches have been used for generation of strong neutron fluxes on the MA class pulse power machines. Due to the low electron density of deuterium Z-pinch plasma, regular laser diagnostics in the visible range cannot be used for observation and study of the pinch. Laser probing at the wavelength of 1064 nm was used for visualization of deuterium plasma. Infrared schlieren and interferometry diagnostics showed the deuterium gas puff plasma dynamics, instabilities, and allowed for the reconstruction of the profile of the plasma density.

  5. Chemical Behaviors of Energetic Deuterium Implanted into Boron Coatings

    SciTech Connect

    Kodama, H.; Morimoto, Y.; Sasaki, M.; Oyaidu, M.; Oya, Y.; Sagara, A.; Noda, N.; Okuno, K.

    2003-09-15

    To study chemical behaviors of energetic deuterium implanted into boron coating deposited by boronization in fusion devices, two types of boron coating film deposited on silicon and IG-430U were prepared by Plasma Chemical Vapor Deposition (PCVD) technique. Boron polycrystal was used as the reference sample. The chemical behavior of deuterium was investigated by XPS (X-ray photoelectron spectroscopy) and TDS (Thermal adsorption spectroscopy).The 1.0 keV D{sub 2}{sup +} ions were implanted into the samples and the deuterium desorption behavior was studied by TDS. The TDS spectra showed that there were two deuterium release peaks at around 550 and 750 K, which were attributed to the release from deuterium trapped by boron and carbon, respectively. It was also found that most of implanted deuterium was trapped in carbon trapping site compared with boron one.In XPS measurements, the chemical shift of B-1s towards positive side was observed in the film on IG-430U after D{sub 2}{sup +} ion implantation. However, no chemical shifts were found in the film on silicon and boron polycrystal. In highly concentrated boron materials, even if deuterium was implanted into the boron materials, the amount of B-D bond was too low to be measured by XPS. This suggests that deuterium implanted into highly pure boron materials wasn't almost trapped, so that the retention of deuterium in the boron materials would be reduced, compared that in carbon materials.

  6. Neutron production from puffing deuterium in plasma focus device

    SciTech Connect

    Kubes, P.; Cikhardt, J.; Kortanek, J.; Batobolotova, B.; Rezac, K.; Klir, D.; Kravarik, J.; Paduch, M.; Zielinska, E.; Surala, W.; Sadowski, M. J.; Scholz, M.; Karpinski, L.

    2014-08-15

    The current research has continued on the PF-1000 plasma focus device at the current of 2 MA by comparison of the shots with and without injected deuterium. The increase of the total neutron yield at the level of 10{sup 10}–10{sup 11} per shot was achieved after the compression of about 10 μg/cm of the deuterium from the gas-valve by about 46 μg/cm of the neon or deuterium plasma sheath. It increases five times at the decrease of the puffing deuterium mass to one-half. In shots with neon in the chamber and with puffing deuterium, a considerable decrease was confirmed of the soft X-ray emission in comparison with shots without deuterium injection. This decrease can be explained by the absence of the neon in the region of the compressed and hot plasma. The deuterium plasma from the gas-puff should then be confined in the internal structures both in the phase of implosion as well as during their formation and transformation. In shots with puffing deuterium, the evolution of instabilities in the plasma column was suppressed. The deuterium plasma has a higher conductance and better ability to form expressive and dense plasmoids and to transport the internal current in comparison with neon plasma. Neutrons were produced both at the initial phase of stagnation, as well as at a later time at the evolution of the constrictions and dense plasmoids.

  7. A universal equation of state for solids

    NASA Technical Reports Server (NTRS)

    Vinet, P.; Ferrante, J.; Smith, J. R.; Rose, J. H.

    1986-01-01

    The total energy versus interatomic spacing of ionic, metallic, covalent, and rare-gas solids is examined, and a universal form for pressure as a function of volume for all classes of solids in compression is derived. The relation is shown to hold for pressure-volume data for hydrogen and deuterium, xenon, cesium, molybdenum, sodium chloride, and magnesium oxide.

  8. A universal equation of state for solids

    NASA Technical Reports Server (NTRS)

    Vinet, P.; Ferrante, J.; Smith, J. R.; Rose, J. H.

    1986-01-01

    The total energy versus interatomic spacing of ionic, metallic, covalent, and rare-gas solids is examined, and a universal form for pressure as a function of volume for all classes of solids in compression is derived. The relation is shown to hold for pressure-volume data for hydrogen and deuterium, xenon, cesium, molybdenum, sodium chloride, and magnesium oxide.

  9. Deuterium implantation into Y2O3-doped and pure tungsten: Deuterium retention and blistering behavior

    NASA Astrophysics Data System (ADS)

    Zhao, M.; Jacob, W.; Manhard, A.; Gao, L.; Balden, M.; von Toussaint, U.; Zhou, Z.

    2017-04-01

    The blistering and near-surface deuterium retention of a Y2O3-doped tungsten (W) and two different pure W grades were studied after exposure to deuterium (D) plasma at elevated temperatures (370, 450 and 570 K). Samples were exposed to a deuterium fluence of 6 × 1024 D m-2 applying a moderate ion flux of about 9 × 1019 D m-2 s-1 at an ion energy of 38 eV/D. Morphological modifications at the surface were analyzed by confocal laser scanning microscopy and scanning electron microscopy. The D depth profiles and the accumulated D inventories within the topmost 8 μm were determined by nuclear reaction analysis. Blistering and deuterium retention were strongly dependent on the implantation temperature. In addition, blistering was sensitively influenced by the used tungsten grade, although the total amount of retained D measured by nuclear reaction analysis was comparable. Among the three different investigated tungsten grades, Y2O3-doped W exhibited the lowest degree of surface modification despite a comparable total D retention.

  10. Deuterium retention in tungsten exposed to low-energy pure and helium-seeded deuterium plasmas

    NASA Astrophysics Data System (ADS)

    Ogorodnikova, O. V.; Schwarz-Selinger, T.; Sugiyama, K.; Alimov, V. Kh.

    2011-01-01

    Influence of helium (He) on the deuterium (D) retention in tungsten (W) under simultaneous He-D plasma exposure was investigated. Bulk polycrystalline tungsten and two W coatings on carbon substrate, namely, plasma-sprayed tungsten and combined magnetron-sputtered and ion implanted tungsten (CMSII-W) were exposed to pure and He-seeded D plasmas generated by electron-cyclotron-resonance plasma source. The D retention in each sample was subsequently analyzed by various methods such as nuclear reaction analysis for the D depth profiling up to 6 μm and thermal desorption spectroscopy for the determination of total amount of D retention. It is shown that seeding of helium into D plasma with helium ion flux fraction of 10% reduces the deuterium retention for all tungsten grades but more significant reduction was observed for polycrystalline W and less significant effect was found for W coatings. From the thermal desorption spectroscopy measurements, we conclude that the presence of He modifies the density of existing traps for D but does not modify the nature of traps. Maximum effect of a reduction in the deuterium retention due to helium seeding was observed at around 500 K for bulk polycrystalline W. Mechanisms of deuterium retention and He effect in different W materials are discussed.

  11. Energy Migration Involving Irradiated Solids

    DTIC Science & Technology

    1976-04-30

    the illtamirAted surface and cocponents or the gas phase (termed photo.assisted gas/sar race reaction ), (iv) enhazsced catalytic activity or the...acetaldehyde and ethanol; photoassisted reduction or nitrous oxide or nicthyl iodide and photoassisted oxidation or ethlanol via chemical reaction ...chemical reaction with ZnOl; and fast release of I ID via photolysis of surface OH and OD Sroups on zinc oxide was readily distinguished fremn slower

  12. Dispersion in DLA metallicities and deuterium abundances

    NASA Astrophysics Data System (ADS)

    Dvorkin, Irina; Silk, Joseph; Vangioni, Elisabeth; Petitjean, Patrick; Olive, Keith A.

    2017-03-01

    Recent chemical abundance measurements of damped Lyman-alpha absorbers (DLAs) revealed a large intrinsic scatter in their metallicities. We discuss a semi-analytic model that was specifically designed to study this scatter by tracing the chemical evolution of the interstellar matter in small regions of the Universe with different mean density, from over- to underdense regions. It is shown that different histories of structure formation in these regions are reflected in the chemical properties of the proto-galaxies. We also address deuterium abundance measurements, which constitute a complementary probe of the star formation and infall histories.

  13. Lamb shift in the muonic deuterium atom

    SciTech Connect

    Krutov, A. A.; Martynenko, A. P.

    2011-11-15

    We present an investigation of the Lamb shift (2P{sub 1/2}-2S{sub 1/2}) in the muonic deuterium ({mu}D) atom using the three-dimensional quasipotential method in quantum electrodynamics. The vacuum polarization, nuclear-structure, and recoil effects are calculated with the account of contributions of orders {alpha}{sup 3}, {alpha}{sup 4}, {alpha}{sup 5}, and {alpha}{sup 6}. The results are compared with earlier performed calculations. The obtained numerical value of the Lamb shift at 202.4139 meV can be considered a reliable estimate for comparison with forthcoming experimental data.

  14. Deuterium and He-3 in cosmic rays

    NASA Technical Reports Server (NTRS)

    Stephens, S. A.

    1989-01-01

    Observation of a large flux of antiprotons in cosmic rays prompted many to postulate new ideas relating to the origin and propagation of cosmic rays in the Galaxy, within the framework of the secondary hypothesis. Under this hypothesis, cosmic rays traverse a large amount of matter either in the source region or in the interstellar space. As a result, large amounts of deuterium and He-3 are also produced as a consequence of spallation of helium and heavier nuclei. In this paper, the spectra of these isotopes are derived, using various models for the propagation of cosmic rays and compare with the existing observations.

  15. Novel PEFC Application for Deuterium Isotope Separation.

    PubMed

    Matsushima, Hisayoshi; Ogawa, Ryota; Shibuya, Shota; Ueda, Mikito

    2017-03-16

    The use of a polymer electrolyte fuel cell (PEFC) with a Nafion membrane for isotopic separation of deuterium (D) was investigated. Mass analysis at the cathode side indicated that D diffused through the membrane and participated in an isotope exchange reaction. The exchange of D with protium (H) in H₂O was facilitated by a Pt catalyst. The anodic data showed that the separation efficiency was dependent on the D concentration in the source gas, whereby the water produced during the operation of the PEFC was more enriched in D as the D concentration of the source gas was increased.

  16. Novel PEFC Application for Deuterium Isotope Separation

    PubMed Central

    Matsushima, Hisayoshi; Ogawa, Ryota; Shibuya, Shota; Ueda, Mikito

    2017-01-01

    The use of a polymer electrolyte fuel cell (PEFC) with a Nafion membrane for isotopic separation of deuterium (D) was investigated. Mass analysis at the cathode side indicated that D diffused through the membrane and participated in an isotope exchange reaction. The exchange of D with protium (H) in H2O was facilitated by a Pt catalyst. The anodic data showed that the separation efficiency was dependent on the D concentration in the source gas, whereby the water produced during the operation of the PEFC was more enriched in D as the D concentration of the source gas was increased. PMID:28772661

  17. The role of oxygen in the uptake of deuterium in lithiated graphite

    SciTech Connect

    Taylor, C. N.; Luitjohan, K. E.; Dadras, J.; Allain, J. P.; Krstic, P. S.; Skinner, C. H.

    2013-12-14

    We investigate the mechanism of deuterium retention by lithiated graphite and its relationship to the oxygen concentration through surface sensitive experiments and atomistic simulations. Deposition of lithium on graphite yielded 5%–8% oxygen surface concentration and when subsequently irradiated with D ions at energies between 500 and 1000 eV/amu and fluences over 10{sup 16} cm{sup −2} the oxygen concentration rose to between 25% and 40%. These enhanced oxygen levels were reached in a few seconds compared to about 300 h when the lithiated graphite was allowed to adsorb oxygen from the ambient environment under equilibrium conditions. Irradiating graphite without lithium deposition, however, resulted in complete removal of oxygen to levels below the detection limit of XPS (e.g., <1%). These findings confirm the predictions of atomistic simulations, which had concluded that oxygen was the primary component for the enhanced hydrogen retention chemistry on the lithiated graphite surface.

  18. The role of oxygen in the uptake of deuterium in lithiated graphite

    SciTech Connect

    C.N. Taylor; J. Dadras; K.E. Luitjohan; J.P. Allain; P.S. Krstic; C.H. Skinner

    2013-12-01

    We investigate the mechanism of deuterium retention by lithiated graphite and its relationship to the oxygen concentration through surface sensitive experiments and atomistic simulations. Deposition of lithium on graphite yielded 5%–8% oxygen surface concentration and when subsequently irradiated with D ions at energies between 500 and 1000?eV/amu and fluences over 1016?cm-2 the oxygen concentration rose to between 25% and 40%. These enhanced oxygen levels were reached in a few seconds compared to about 300?h when the lithiated graphite was allowed to adsorb oxygen from the ambient environment under equilibrium conditions. Irradiating graphite without lithium deposition, however, resulted in complete removal of oxygen to levels below the detection limit of XPS (e.g., <1%). These findings confirm the predictions of atomistic simulations, which had concluded that oxygen was the primary component for the enhanced hydrogen retention chemistry on the lithiated graphite surface.

  19. Electroproduction of kaons on hydrogen and deuterium

    NASA Astrophysics Data System (ADS)

    Koltenuk, Douglas Michael

    1999-10-01

    High-statistics data have been acquired for the reactions p(e,e'K+) and d(e,eK+) over a range of W from 1.70-1.95 GeV. Coincidence measurements at Q 2 = 0.38, 0.50, and 0.52 GeV2 cover a range of virtual photon-kaon angles for both liquid hydrogen and deuterium targets. Monte Carlo simulations have been matched to the data in order to extract cross sections. The W-dependence of the p(e,e'K+)Λ and p(e,e'K+)Σ0 cross sections deviates from a previous model fitted to photoproduction data. The difference in cross sections on hydrogen and on the proton in deuterium has been quantified for Λ production. The subtraction of the Λ and Σ 0 contribution from the proton in the deuteron allows the extraction of n(e,e'K+)Σ- cross sections. The wealth of new data on Λ, Σ0, and Σ - production will put tight constraints on existing models for kaon production and form factors.

  20. Cryotarget Control Software for Liquid Deuterium

    NASA Astrophysics Data System (ADS)

    Brakman, David; Gilfoyle, Gerard; Cuevas, Chris; Christo, Steve; CLAS Collaboration

    2015-10-01

    One of the experiments in Hall B at Jefferson Lab will measure the neutron elastic magnetic form factor with a 12 GeV electron beam striking a liquid deuterium target (LD2) and measuring the resulting debris in the CEBAF Large Acceptance Spectrometer (CLAS12). A program was created that acts as a control system for the LD2 target. It will monitor the deuterium target and send data to the main control system and the shift workers monitoring the experiment in real time. The data include measurements of pressure, temperature, and liquid level. The system will also control setpoints for temperature, heater power, and other parameters as well as download calibration curves. The program was written in LabVIEW, a graphical programming language noted for readily interfacing with lab equipment. This project has completed two stages so far. Simulated data were generated within LabVIEW and passed to subroutines that send, log, and display data on a PC. In the second stage, the PC was connected to a data acquisition board, and test signals were read and analyzed to simulate the target sensors. Work supported by the University of Richmond and the US Department of Energy.

  1. Cold versus hot fusion deuterium branching ratios

    SciTech Connect

    Fox, H.; Bass, R.

    1995-12-31

    A major source of misunderstanding of the nature of cold nuclear fusion has been the expectation that the deuterium branching ratios occurring within a palladium lattice would be consistent with the gas-plasma branching ratios. This misunderstanding has led to the concept of the dead graduate student, the 1989`s feverish but fruitless search for neutron emissions from cold fusion reactors, and the follow-on condemnation of the new science of cold fusion. The experimental facts are that in a properly loaded palladium lattice, the deuterium fusion produces neutrons at little above background, a greatly less-than-expected production of tritium (the tritium desert), and substantially more helium-4 than is observed in hot plasma physics. The experimental evidence is now compelling (800 reports of success from 30 countries) that cold nuclear fusion is a reality, that the branching ratios are unexpected, and that a new science is struggling to be recognized. Commercialization of some types of cold fusion devices has already begun.

  2. Thermal desorption of deuterium implanted into beryllium

    SciTech Connect

    Markin, A.V.; Chernikov, V.N.; Zakharov, A.P.

    1995-09-01

    By means of TDS measurements it is shown that the desorption of deuterium from Be implanted with 5 keV D ions to fluences, {Phi}, from 1x10{sup 20} D/m{sup 2} to 1x10{sup 21} D/m{sup 2} proceeds in one high temperature stage B, while at {Phi} {ge} 1.2x10{sup 21}D/m{sup 2} one more stage A is added. The desorption maximum A is narrow and consists of two peaks A{sub 1} and A{sub 2} at about 460 K and 490 K, respectively. Peak A{sub 1} is attributed to the desorption of deuterium from the walls of opened channels formed under D ion implantation. Peak {sub A}2 is a consequence of the opening of a part of closed bubbles/channels to the outer surface. The position of maximum B shifts noticeably and nonsteadily on the fluence in a range from 850 to 1050 K. The origin of this maximum is the liberation of D atoms bound at vacancy complexes discussed previously by Wampler. The dependence of Tm(B) on the fluence is governed by the interaction of freely migrating D atoms with partly opened or fully closed gas cavity arrangements which are created under temperature ramping, but differently in specimens implanted with D ions to different fluences.

  3. Deuterium in North Atlantic storm tops

    NASA Technical Reports Server (NTRS)

    Smith, Ronald B.

    1992-01-01

    During the ERICA project in 1989, ice crystals were collected from the tops of two winter storms and one broad cirrus cloud. Deuterium concentration in the storm ice samples, together with a model of isotope fractionation, are used to determine the temperature where the ice was formed. Knowledge of the ice formation temperature allows us to determine whether the ice has fallen or been lofted to the altitude of collection. In both storms, the estimated fall distance decreases upward. In the 21 January storm, the fall distance decreases to zero at the cloud top. In the 23 January storm, the fall distance decreases to zero at a point 2 km below the cloud top and appears to become negative above, indicating lofted ice. Cloud particle data from the cloud tops show an ice-to-vapor ratio greater than one and indicate the presence of particles with small terminal velocities; both observations support the idea of ice lofting. The satellite-derived cloud tops lie well below the actual cloud top (e.g., 2.5 km below on 23 January), indicating that the lofted ice in winter storms may not be detectable from space using IR radiance techniques. A comparison of deuterium in cloud-top ice and clear-air vapor suggests that even in winter, when vertical air motions are relatively weak, lofted ice crystals are the dominant source of water vapor in the upper troposphere.

  4. Muon capture in hydrogen and deuterium

    NASA Astrophysics Data System (ADS)

    Petitjean, Claude

    2009-09-01

    We report on a new generation of muon lifetime experiments at PSI to measure the nuclear muon capture rate in hydrogen and deuterium with ≤1% accuracy. The goals are to determine in μp capture the induced pseudoscalar coupling g P predicted in HBchPT, and in μd capture the axial two-body current term L1 A described by modern EFT’s. For the μp experiment a hydrogen TPC was developed as active muon stop detector, surrounded by cylindrical wire chambers and a plastic hodoscope as electron detector. Ultra-high purity of the hydrogen isotope ^1H_1 at levels below 10 - 8 was achieved with a specially developed gas circulation and purification system, and with a novel isotope separation column. About 2 ·1010 events were collected which are now in final analysis. Data from the first production run result in g P = 7.3 ± 1.1 in good agreement with theory. The μd experiment is in development. It requires measurements in ultra-pure, cold deuterium gas at ˜30K. For this we are constructing a new Cryo-TPC.

  5. Deuterium anions in inertial electrostatic confinement devices.

    PubMed

    Boris, D R; Alderson, E; Becerra, G; Donovan, D C; Egle, B; Emmert, G A; Garrison, L; Kulcinski, G L; Santarius, J F; Schuff, C; Zenobia, S J

    2009-09-01

    A magnetic deflection-energy analyzer and Faraday trap diagnostic have been used to make measurements of divergent deuterium anion flow in the inertial electrostatic confinement experiment at the University of Wisconsin-Madison (UW-IEC) [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, I. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)], a device to confine high-energy light ions in a spherically symmetric electrostatic potential well. Deuterium anion current densities as high as 8.5 microA/cm2 have been measured at the wall of the UW-IEC device, 40 cm from the surface of the device cathode with a detector assembly of admittance area 0.7 cm2. Energy spectra obtained using a magnetic deflection-energy analyzer diagnostic indicate the presence of D2(-), and D- ions produced through thermal electron attachment near the device cathode, as well as D- ions produced via charge-transfer processes between the anode and cathode of the device.

  6. Deuterium anions in inertial electrostatic confinement devices

    NASA Astrophysics Data System (ADS)

    Boris, D. R.; Alderson, E.; Becerra, G.; Donovan, D. C.; Egle, B.; Emmert, G. A.; Garrison, L.; Kulcinski, G. L.; Santarius, J. F.; Schuff, C.; Zenobia, S. J.

    2009-09-01

    A magnetic deflection-energy analyzer and Faraday trap diagnostic have been used to make measurements of divergent deuterium anion flow in the inertial electrostatic confinement experiment at the University of Wisconsin-Madison (UW-IEC) [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, I. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)], a device to confine high-energy light ions in a spherically symmetric electrostatic potential well. Deuterium anion current densities as high as 8.5μA/cm2 have been measured at the wall of the UW-IEC device, 40 cm from the surface of the device cathode with a detector assembly of admittance area 0.7cm2 . Energy spectra obtained using a magnetic deflection-energy analyzer diagnostic indicate the presence of D2- , and D- ions produced through thermal electron attachment near the device cathode, as well as D- ions produced via charge-transfer processes between the anode and cathode of the device.

  7. Confinement and heating of a deuterium-tritium plasma

    SciTech Connect

    Hawryluk, R. J.; Adler, H.; Alling, P.; Synakowski, E.

    1994-03-01

    The Tokamak Fusion Test Reactor (TFTR) has performed initial high-power experiments with the plasma fueled by deuterium and tritium to nominally equal densities. Compared to pure deuterium plasmas, the energy stored in the electron and ions increased by ~20%. These increases indicate improvements in confinement associated with the use of tritium and possibly heating of electrons by α-particles.

  8. (Un)true deuterium abundance in the Galactic disk

    NASA Astrophysics Data System (ADS)

    Prodanović, Tijana; Steigman, Gary; Fields, Brian D.

    2010-04-01

    Deuterium has a special place in cosmology, nuclear astrophysics, and galactic chemical evolution, because of its unique property that it is only created in the big bang nucleosynthesis while all other processes result in its net destruction. For this reason, among other things, deuterium abundance measurements in the interstellar medium (ISM) allow us to determine the fraction of interstellar gas that has been cycled through stars, and set constraints and learn about different Galactic chemical evolution (GCE) models. However, recent indications that deuterium might be preferentially depleted onto dust grains complicate our understanding about the meaning of measured ISM deuterium abundances. For this reason, recent estimates by Linsky et al. (2006) have yielded a lower bound to the “true”, undepleted, ISM deuterium abundance that is very close to the primordial abundance, indicating a small deuterium astration factor contrary to the demands of many GCE models. To avoid any prejudice about deuterium dust depletion along different lines of sight that are used to determine the “true” D abundance, we propose a model-independent, statistical Bayesian method to address this issue and determine in a model-independent manner the undepleted ISM D abundance. We find the best estimate for the gas-phase ISM deuterium abundance to be (D/H)ISM ≥ (2.0 ± 0.1) × 10-5. Presented are the results of Prodanović et al. (2009).

  9. Deuterium astration in the local disc and beyond

    NASA Astrophysics Data System (ADS)

    Romano, Donatella; Tosi, Monica; Chiappini, Cristina; Matteucci, Francesca

    2006-06-01

    Estimates of the interstellar deuterium abundance span a wide range of values. Until recently, it was customary to adopt the abundance of deuterium measured in the Local Bubble as representative of the local one. Now, it is becoming unclear whether the true local deuterium abundance is significantly higher or lower than this value, depending on the interpretation given to current data. It is important to deal with the issue of the deuterium variation and see whether it challenges our current understanding of the Galaxy evolution. To this aim, we study the evolution of deuterium in the framework of successful models for the chemical evolution of the Milky Way able to reproduce the majority of the observational constraints for the solar neighbourhood and for the Galactic disc. We show that, in the framework of our models, the lowest D/H (deuterium-to-oxygen) values observed locally cannot be explained in terms of simple astration processes occurring during the Galaxy evolution. Indeed, the combination of a mild star formation and a continuous infall of unprocessed gas required to fit all the available observational data allows only a modest variation of the deuterium abundance from its primordial value. Therefore, we suggest that depletion of deuterium on to dust grains is the most likely physical mechanism proposed so far to explain the observed dispersion in the local data.

  10. Deuterium enrichment by selective photoinduced dissociation of a multihalogenated organic compound

    DOEpatents

    Marling, John B.; Herman, Irving P.

    1981-01-01

    A method for deuterium enrichment by photoinduced dissociation which uses as the deuterium source a multihalogenated organic compound selected from the group consisting of a dihalomethane, a trihalomethane, a 1,2-dihaloethene, a trihaloethene, a tetrahaloethane and a pentahaloethane. The multihalogenated organic compound is subjected to intense infrared radiation at a preselected wavelength to selectively excite and thereby induce dissociation of substantially only those molecules containing deuterium to provide a deuterium enriched dissociation product. The deuterium enriched product may be combusted with oxygen to provide deuterium enriched water. The deuterium depleted undissociated molecules may be redeuterated by treatment with a deuterium source such as water.

  11. Deuterium absorption and material phase characteristics of Zr{sub 2}Fe

    SciTech Connect

    Nobile, A.; Mosley, W.C.; Holder, J.S.; Brooks, K.N.

    1992-12-30

    Scanning electron microscope (SEM) images of polished surfaces, electron probe microanalysis, and X-ray powder diffractometry indicated the presence of a continuous Zr{sub 2}Fe phase with secondary phases of ZrFe{sub 2}, Zr{sub 5}FeSn, {alpha}-Zr, and Zr{sub 6}Fe{sub 3}O. A statistically-designed experiment to determine the effects of temperature, time, and vacuum quality On activation of St 198 revealed that when activated at low temperature (350{degrees}C) deuterium absorption rate was slower when the vacuum quality was pwr (2.5 Pa vs. 3{times}10{sup {minus}4} Pa). However, at higher activation temperature (500{degrees}C), deuterium absorption rate was fast and was independent of vacuum quality. Deuterium pressure-composition-temperature (P-C-T) data are reported for St 198 in the temperature range 200--500{degrees}C. The P-C-T data over the full range of deuterium loading and at temperatures of 350{degrees}C and below is described by: K{sub 0e}-({Delta}H{sub {alpha}}/RT)=PD{sub 2}q{sup 2}/(q*{minus}q){sup 2} where {Delta}H{alpha} and K{sub 0} have values of 101.8 kJ{center_dot}mole{sup {minus}1} and 3.24{times}10{sup {minus}8}Pa{sup {minus}1}, and q* is 15.998 kPa{center_dot}L{sup {minus}1}{center_dot}g{sup {minus}1}. At higher temperatures, one or more secondary reactions in the solid phase occur that slowly consume D{sub 2} from the gas phase. XRD suggests these reactions to be: 2 Zr{sub 2}FeD{sub x} {yields} x ZrD{sub 2} + x/3 ZrFe{sub 2} + (2 {minus} 2/3x) Zr{sub 2}Fe and Zr{sub 2}FeD{sub x} + (2 {minus}1/2x) D{sub 2} {yields} ZrD{sub 2} + Fe, where 0 < x < 3. Reaction between gas phase deuterium and Zr2FC formed in the first reaction accounts for the observed consumption of deuterium from the gas phase by this reaction.

  12. Thermal conductivities for sintered and sphere-pac Li/sub 2/O and. gamma. /sup -/LiAlO/sub 2/ solid breeders with and without irradiation effects

    SciTech Connect

    Liu, Y.Y.; Tam, S.W.

    1984-07-01

    Thermal conductivities (k, k/sub eff/) have been estimated for sintered and sphere-pac Li/sub 2/O and ..gamma..-LiAlO/sub 2/ with and without neutron irradiation effects. The estimation is based on (1) data from unirradiated UO/sub 2/, Li/sub 2/O, and ..gamma..-LiAlO/sub 2/; (2) data from irradiated dielectric insulator materials; and (3) relatively simple physical models. Comparison of model predictions with limited ex- and in-reactor data found reasonable agreement, thus lending credence for their use in design applications. The impact of thermal conductivities on tritium breeding and power generation in fusion solid-breeder blankets is briefly highlighted.

  13. Hydrogen retention in ion irradiated steels

    SciTech Connect

    Hunn, J.D.; Lewis, M.B.; Lee, E.H.

    1998-11-01

    In the future 1--5 MW Spallation Neutron Source, target radiation damage will be accompanied by high levels of hydrogen and helium transmutation products. The authors have recently carried out investigations using simultaneous Fe/He,H multiple-ion implantations into 316 LN stainless steel between 50 and 350 C to simulate the type of radiation damage expected in spallation neutron sources. Hydrogen and helium were injected at appropriate energy and rate, while displacement damage was introduced by nuclear stopping of 3.5 MeV Fe{sup +}, 1 {micro}m below the surface. Nanoindentation measurements showed a cumulative increase in hardness as a result of hydrogen and helium injection over and above the hardness increase due to the displacement damage alone. TEM investigation indicated the presence of small bubbles of the injected gases in the irradiated area. In the current experiment, the retention of hydrogen in irradiated steel was studied in order to better understand its contribution to the observed hardening. To achieve this, the deuterium isotope ({sup 2}H) was injected in place of natural hydrogen ({sup 1}H) during the implantation. Trapped deuterium was then profiled, at room temperature, using the high cross-section nuclear resonance reaction with {sup 3}He. Results showed a surprisingly high concentration of deuterium to be retained in the irradiated steel at low temperature, especially in the presence of helium. There is indication that hydrogen retention at spallation neutron source relevant target temperatures may reach as high as 10%.

  14. Water Behavior in Bacterial Spores by Deuterium NMR Spectroscopy

    PubMed Central

    2015-01-01

    Dormant bacterial spores are able to survive long periods of time without nutrients, withstand harsh environmental conditions, and germinate into metabolically active bacteria when conditions are favorable. Numerous factors influence this hardiness, including the spore structure and the presence of compounds to protect DNA from damage. It is known that the water content of the spore core plays a role in resistance to degradation, but the exact state of water inside the core is a subject of discussion. Two main theories present themselves: either the water in the spore core is mostly immobile and the core and its components are in a glassy state, or the core is a gel with mobile water around components which themselves have limited mobility. Using deuterium solid-state NMR experiments, we examine the nature of the water in the spore core. Our data show the presence of unbound water, bound water, and deuterated biomolecules that also contain labile deuterons. Deuterium–hydrogen exchange experiments show that most of these deuterons are inaccessible by external water. We believe that these unreachable deuterons are in a chemical bonding state that prevents exchange. Variable-temperature NMR results suggest that the spore core is more rigid than would be expected for a gel-like state. However, our rigid core interpretation may only apply to dried spores whereas a gel core may exist in aqueous suspension. Nonetheless, the gel core, if present, is inaccessible to external water. PMID:24950158

  15. Characterisation of deuterium spectra from laser driven multi-species sources by employing differentially filtered image plate detectors in Thomson spectrometers

    NASA Astrophysics Data System (ADS)

    Alejo, A.; Kar, S.; Ahmed, H.; Krygier, A. G.; Doria, D.; Clarke, R.; Fernandez, J.; Freeman, R. R.; Fuchs, J.; Green, A.; Green, J. S.; Jung, D.; Kleinschmidt, A.; Lewis, C. L. S.; Morrison, J. T.; Najmudin, Z.; Nakamura, H.; Nersisyan, G.; Norreys, P.; Notley, M.; Oliver, M.; Roth, M.; Ruiz, J. A.; Vassura, L.; Zepf, M.; Borghesi, M.

    2014-09-01

    A novel method for characterising the full spectrum of deuteron ions emitted by laser driven multi-species ion sources is discussed. The procedure is based on using differential filtering over the detector of a Thompson parabola ion spectrometer, which enables discrimination of deuterium ions from heavier ion species with the same charge-to-mass ratio (such as C6 +, O8 +, etc.). Commonly used Fuji Image plates were used as detectors in the spectrometer, whose absolute response to deuterium ions over a wide range of energies was calibrated by using slotted CR-39 nuclear track detectors. A typical deuterium ion spectrum diagnosed in a recent experimental campaign is presented, which was produced from a thin deuterated plastic foil target irradiated by a high power laser.

  16. Characterisation of deuterium spectra from laser driven multi-species sources by employing differentially filtered image plate detectors in Thomson spectrometers

    SciTech Connect

    Alejo, A.; Kar, S. Ahmed, H.; Doria, D.; Green, A.; Jung, D.; Lewis, C. L. S.; Nersisyan, G.; Krygier, A. G.; Freeman, R. R.; Clarke, R.; Green, J. S.; Notley, M.; Fernandez, J.; Fuchs, J.; Kleinschmidt, A.; Roth, M.; Morrison, J. T.; Najmudin, Z.; Nakamura, H.; and others

    2014-09-15

    A novel method for characterising the full spectrum of deuteron ions emitted by laser driven multi-species ion sources is discussed. The procedure is based on using differential filtering over the detector of a Thompson parabola ion spectrometer, which enables discrimination of deuterium ions from heavier ion species with the same charge-to-mass ratio (such as C{sup 6+}, O{sup 8+}, etc.). Commonly used Fuji Image plates were used as detectors in the spectrometer, whose absolute response to deuterium ions over a wide range of energies was calibrated by using slotted CR-39 nuclear track detectors. A typical deuterium ion spectrum diagnosed in a recent experimental campaign is presented, which was produced from a thin deuterated plastic foil target irradiated by a high power laser.

  17. Characterisation of deuterium spectra from laser driven multi-species sources by employing differentially filtered image plate detectors in Thomson spectrometers.

    PubMed

    Alejo, A; Kar, S; Ahmed, H; Krygier, A G; Doria, D; Clarke, R; Fernandez, J; Freeman, R R; Fuchs, J; Green, A; Green, J S; Jung, D; Kleinschmidt, A; Lewis, C L S; Morrison, J T; Najmudin, Z; Nakamura, H; Nersisyan, G; Norreys, P; Notley, M; Oliver, M; Roth, M; Ruiz, J A; Vassura, L; Zepf, M; Borghesi, M

    2014-09-01

    A novel method for characterising the full spectrum of deuteron ions emitted by laser driven multi-species ion sources is discussed. The procedure is based on using differential filtering over the detector of a Thompson parabola ion spectrometer, which enables discrimination of deuterium ions from heavier ion species with the same charge-to-mass ratio (such as C(6+), O(8+), etc.). Commonly used Fuji Image plates were used as detectors in the spectrometer, whose absolute response to deuterium ions over a wide range of energies was calibrated by using slotted CR-39 nuclear track detectors. A typical deuterium ion spectrum diagnosed in a recent experimental campaign is presented, which was produced from a thin deuterated plastic foil target irradiated by a high power laser.

  18. Deuterium in the outer Solar System: evidence for two distinct reservoirs.

    PubMed

    Owen, T; Lutz, B L; de Bergh, C

    1986-03-20

    We have just completed a series of determinations of the CH3D/CH4 ratio in the atmospheres of Saturn, Titan and Uranus. These results, coupled with the work of other investigators, suggest that the Solar System contains at least two distinctly different primordial reservoirs of deuterium: that contained in gaseous hydrogen and that contained in the volatiles which have been maintained at low temperatures or isolated from hydrogen; for example, trapped in cold, solid material. Both of these reservoirs were established before the formation of the Solar System.

  19. Deuterium in the outer solar system - Evidence for two distinct reservoirs

    NASA Technical Reports Server (NTRS)

    Owen, T.; Lutz, B. L.; De Bergh, C.

    1986-01-01

    A series of determinations of the CH3D/CH4 ratio in the atmospheres of Saturn, Titan, and Uranus has been completed. These results, coupled with the work of other investigators, suggest that the solar system contains at least two distinctly different primordial reservoirs of deuterium: that contained in gaseous hydrogen and that contained in the volatiles which have been maintained at low temperatures or isolated from hydrogen; for example, trapped in cold, solid material. Both of these reservoirs were established before the formation of the solar system.

  20. Chiral glycine formation on cold interstellar grains by quantum tunneling hydrogen-deuterium substitution reactions

    NASA Astrophysics Data System (ADS)

    Oba, Yasuhiro; Watanabe, Naoki; Osamura, Yoshihiro; Kouchi, Akira

    2015-08-01

    We report experimental evidence that chiral glycine (NH2CHDCOOH) is formed by the surface reaction of normal glycine (NH2CH2COOH) solid with deuterium (D) atom at 12 K under the simulative conditions of interstellar molecular clouds. Chiral glycine formation is most likely initiated by the tunneling abstraction reaction of H atom by D atom followed by the addition of D atom to the glycine radical (NH2CHCOOH). Given that chiral glycine can form in such a primordial low-temperature environment, it might source molecular chirality as molecular clouds evolve into planetary systems.

  1. Deuterium Abundance in Consciousness and Current Cosmology

    NASA Astrophysics Data System (ADS)

    Rauscher, Elizabeth A.

    We utilize the deuterium-hydrogen abundances and their role in setting limits on the mass and other conditions of cosmogenesis and cosmological evolution. We calculate the dependence of a set of physical variables such as density, temperature, energy mass, entropy and other physical variable parameters through the evolution of the universe under the Schwarzschild conditions as a function from early to present time. Reconciliation with the 3°K and missing mass is made. We first examine the Schwarzschild condition; second, the geometrical constraints of a multidimensional Cartesian space on closed cosmologies, and third we will consider the cosmogenesis and evolution of the universe in a multidimensional Cartesian space, obeying the Schwarzschild condition. Implications of this model for matter creation are made. We also examine experimental evidence for closed versus open cosmologies; x-ray detection of the "missing mass" density. Also the interstellar deuterium abundance, along with the value of the Hubble constant set a general criterion on the value of the curvature constant, k. Once the value of the Hubble constant, H is determined, the deuterium abundance sets stringent restrictions on the value of the curvature constant k by an detailed discussion is presented. The experimental evidences for the determination of H and the primary set of coupled equations to determine D abundance is given. 'The value of k for an open, closed, or flat universe will be discussed in terms of the D abundance which will affect the interpretation of the Schwarzschild, black hole universe. We determine cosmology solutions to Einstein's field obeying the Schwarzschild solutions condition. With this model, we can form a reconciliation of the black hole, from galactic to cosmological scale. Continuous creation occurs at the dynamic blackhole plasma field. We term this new model the multiple big bang or "little whimper model". We utilize the deuteriumhydrogen abundances and their role in

  2. Deuterium enrichment of polycyclic aromatic hydrocarbons by photochemically induced exchange with deuterium-rich cosmic ices

    NASA Technical Reports Server (NTRS)

    Sandford, S. A.; Bernstein, M. P.; Allamandola, L. J.; Gillette, J. S.; Zare, R. N.

    2000-01-01

    The polycyclic aromatic hydrocarbon (PAH) coronene (C24H12) frozen in D2O ice in a ratio of less than 1 part in 500 rapidly exchanges its hydrogen atoms with the deuterium in the ice at interstellar temperatures and pressures when exposed to ultraviolet radiation. Exchange occurs via three different chemical processes: D atom addition, D atom exchange at oxidized edge sites, and D atom exchange at aromatic edge sites. Observed exchange rates for coronene (C24H12)-D2O and d12-coronene (C24D12)-H2O isotopic substitution experiments show that PAHs in interstellar ices could easily attain the D/H levels observed in meteorites. These results may have important consequences for the abundance of deuterium observed in aromatic materials in the interstellar medium and in meteorites. These exchange mechanisms produce deuteration in characteristic molecular locations on the PAHs that may distinguish them from previously postulated processes for D enrichment of PAHs.

  3. Deuterium enrichment of polycyclic aromatic hydrocarbons by photochemically induced exchange with deuterium-rich cosmic ices

    NASA Technical Reports Server (NTRS)

    Sandford, S. A.; Bernstein, M. P.; Allamandola, L. J.; Gillette, J. S.; Zare, R. N.

    2000-01-01

    The polycyclic aromatic hydrocarbon (PAH) coronene (C24H12) frozen in D2O ice in a ratio of less than 1 part in 500 rapidly exchanges its hydrogen atoms with the deuterium in the ice at interstellar temperatures and pressures when exposed to ultraviolet radiation. Exchange occurs via three different chemical processes: D atom addition, D atom exchange at oxidized edge sites, and D atom exchange at aromatic edge sites. Observed exchange rates for coronene (C24H12)-D2O and d12-coronene (C24D12)-H2O isotopic substitution experiments show that PAHs in interstellar ices could easily attain the D/H levels observed in meteorites. These results may have important consequences for the abundance of deuterium observed in aromatic materials in the interstellar medium and in meteorites. These exchange mechanisms produce deuteration in characteristic molecular locations on the PAHs that may distinguish them from previously postulated processes for D enrichment of PAHs.

  4. Muon Catalyzed Fusion in Solid HD

    NASA Astrophysics Data System (ADS)

    Porcelli, T. A.; Beer, G. A.; Knowles, P. E.; Maier, M.; Mason, G. R.; Marshall, G. M.; Olin, A.; Douglas, J.; Fujiwara, M. C.; Ellerbusch, B.; Huber, T. M.; Kammel, P.; Kunselman, A. R.; Adamczak, A.; Bailey, J. M.; Faifman, M.; Markushin, V.; Jacot-Guillarmod, R.; Mulhauser, F.; Schaller, L. A.; Kim, S. K.; Petitjean, C.; Zmeskal, J.

    1997-10-01

    Muons were stopped in a solid hydrogen and tritium target, where muonic protium atoms (μ p) were formed. The muons transferred to tritium, forming muonic tritium atoms (μ t) which were then emitted, traversing a vacuum drift region to a solid HD (deuterium hydride) layer, where muonic deuterium tritium (dt μ) molecules formed via a resonant process, leading to fusion. A brief description of the experimental apparatus will be given. Analysis of the data from an experiment at TRIUMF, along with Monte Carlo simulations, will be presented.

  5. Diffusion, trapping, and isotope exchange of plasma implanted deuterium in ion beam damaged tungsten

    NASA Astrophysics Data System (ADS)

    Barton, Joseph Lincoln

    Tritium accumulation in nuclear fusion reactor materials is a major concern for practical and safe fusion energy. This work examines hydrogen isotope exchange as a tritium removal technique, analyzes the effects of neutron damage using high energy copper ion beams, and introduces a diffusion coefficient that is a function of the concentration of trapped atoms. Tungsten samples were irradiated with high energy (0.5 - 5 MeV) copper ions for controlled levels of damage - 10-3 to 10-1 displacements per atom (dpa) - at room temperature. Samples were then exposed to deuterium plasma at constant temperature (˜ 380 K) to a high fluence of 1024 ions/m2, where retention is at is maximized (i.e. saturated). By then subsequently exposing these samples to fractions of this fluence with hydrogen plasma, isotope exchange rates were observed. The resulting deuterium still trapped in the tungsten is then measured post mortem. Nuclear reaction analysis (NRA) gives the depth resolved deuterium retention profile with the 3He(D,p) 4He reaction, and thermal desorption spectroscopy (TDS) gives the total amount of deuterium trapped in the tungsten by heating a sample in vacuum up to 1200 K and measuring the evaporated gas molecules with a residual gas analyzer. Isotope exchange data show that hydrogen atoms can displace trapped deuterium atoms efficiently only up to the first few microns, but does not affect the atoms trapped at greater depths. In ion damaged tungsten, measurements showed a significant increase in retention in the damage region proportional to dpa 0.66, which results in a significant spike in total retention, and isotope exchange in damaged samples is still ineffective at depths greater than a few microns. Thus, isotope exchange is not an affective tritium removal technique; however, these experiments have shown that trapping in material defects greatly affects diffusion. These experiments lead to a simplified diffusion model with defect densities as the only free

  6. [Biological significance of naturally occurring deuterium: the antitumor effect of deuterium depletion].

    PubMed

    Somlyai, Gábor; Molnár, Miklós; Laskay, Gábor; Szabó, Mariann; Berkényi, Tamás; Guller, Imre; Kovács, András

    2010-09-05

    The concentration of deuterium is about 150 ppm (over 16 mmol/L) in surface water and more than 10 mmol/L in living organisms. Experiments with deuterium depleted water (30+/-5 ppm) revealed that due to D-depletion various tumorous cell lines (PC-3, human prostate, MDA, human breast, HT-29, human colon, M14, human melanoma) required longer time to multiply in vitro. DDW caused tumor regression in xenotransplanted mice (MDA and MCF-7, human breast, PC-3) and induced apoptosis in vitro and in vivo. Deuterium depleted water (25+/-5 ppm) induced complete or partial tumor regression in dogs and cats with spontaneous malignancies, it was registered as anticancer for veterinary use in 1999 (Vetera-DDW-25 A.U.V., 13/99 FVM). The hypodermic preparation of the registered veterinary drug was successfully tested in clinical investigations. Under the permission of the Hungarian Institute of Pharmacology (No. 5621/40/95) a randomized, double blind controlled, human Phase II clinical trial with prostate cancer was performed, in compliance with GCP principles, which exhibited a significant difference between the control and treated groups with respect to the examined parameters, median survival time and the extension of life-span. We suggest that cells are able to regulate the D/H ratio and the changes in the D/H ratio can trigger certain molecular mechanisms having a key role in cell cycle regulation. We suppose that not the shift in the intracellular pH, but the concomitant increase in the D/H ratio is the real trigger for the cells to enter into S phase. The decrease of D concentration can intervene in the signal transduction pathways thus leading to tumor regression. Deuterium depletion may open new perspectives in cancer treatment and prevention helping to increase the effectiveness of current oncotherapies.

  7. Pharmaco-thermodynamics of deuterium-induced oedema in living rat brain via 1H2O MRI: implications for boron neutron capture therapy of malignant brain tumours

    NASA Astrophysics Data System (ADS)

    Medina, Daniel C.; Li, Xin; Springer, Charles S., Jr.

    2005-05-01

    In addition to its common usage as a tracer in metabolic and physiological studies, deuterium possesses anti-tumoural activity and confers protection against γ-irradiation. A more recent interest in deuterium emanates from the search for alternatives capable of improving neutron penetrance whilst reducing healthy tissue radiation dose deposition in boron neutron capture therapy of malignant brain tumours. Despite this potential clinical application, deuterium induces brain oedema, which is detrimental to neutron capture therapy. In this study, five adult male rats were titrated with deuterated drinking water while brain oedema was monitored via water proton magnetic resonance imaging. This report concludes that deuterium, as well as deuterium-induced brain oedema, possesses a uniform brain bio-distribution. At a steady-state blood fluid deuteration value of 16%, when the deuterium isotope fraction in drinking water was 25%, a mean oedematous volume change of 9 ± 2% (p-value <0.001) was observed in the rat brain—this may account for neurological and behavioural abnormalities found in mammals drinking highly deuterated water. In addition to characterizing the pharmaco-thermodynamics of deuterium-induced oedema, this report also estimates the impact of oedema on thermal neutron enhancement and effective dose reduction factors using simple linear transport calculations. While body fluid deuteration enhances thermal neutron flux penetrance and reduces dose deposition, oedema has the opposite effect because it increases the volume of interest, e.g., the brain volume. Thermal neutron enhancement and effective dose reduction factors could be reduced by as much as ~10% in the presence of a 9% water volume increase (oedema). All three authors have contributed equally to this work.

  8. Pharmaco-thermodynamics of deuterium-induced oedema in living rat brain via 1H2O MRI: implications for boron neutron capture therapy of malignant brain tumours.

    PubMed

    Medina, Daniel C; Li, Xin; Springer, Charles S

    2005-05-07

    In addition to its common usage as a tracer in metabolic and physiological studies, deuterium possesses anti-tumoural activity and confers protection against gamma-irradiation. A more recent interest in deuterium emanates from the search for alternatives capable of improving neutron penetrance whilst reducing healthy tissue radiation dose deposition in boron neutron capture therapy of malignant brain tumours. Despite this potential clinical application, deuterium induces brain oedema, which is detrimental to neutron capture therapy. In this study, five adult male rats were titrated with deuterated drinking water while brain oedema was monitored via water proton magnetic resonance imaging. This report concludes that deuterium, as well as deuterium-induced brain oedema, possesses a uniform brain bio-distribution. At a steady-state blood fluid deuteration value of 16%, when the deuterium isotope fraction in drinking water was 25%, a mean oedematous volume change of 9 +/- 2% (p-value <0.001) was observed in the rat brain-this may account for neurological and behavioural abnormalities found in mammals drinking highly deuterated water. In addition to characterizing the pharmaco-thermodynamics of deuterium-induced oedema, this report also estimates the impact of oedema on thermal neutron enhancement and effective dose reduction factors using simple linear transport calculations. While body fluid deuteration enhances thermal neutron flux penetrance and reduces dose deposition, oedema has the opposite effect because it increases the volume of interest, e.g., the brain volume. Thermal neutron enhancement and effective dose reduction factors could be reduced by as much as approximately 10% in the presence of a 9% water volume increase (oedema).

  9. Deuterium permeation and retention in copper alloys

    NASA Astrophysics Data System (ADS)

    Zhou, Hai-Shan; Liu, Hao-Dong; An, Zhong-Qing; Li, Bo; Xu, Yu-Ping; Liu, Feng; Zhao, Ming-Zhong; Xu, Qian; Ding, Fang; Luo, Guang-Nan

    2017-09-01

    For plasma-facing components of ITER, tritium (T) transport into the coolant by permeation through CuCrZr heat sink will raise T safety and recovery issues. In the present work, hydrogen isotope permeation and retention in copper (Cu) materials have been experimentally studied. Deuterium (D) gas-driven permeation (GDP) experiments have been performed to evaluate the permeability and diffusion coefficients. Meanwhile, D retention properties in these Cu materials are compared by gas absorption and subsequent thermal desorption spectroscopy (TDS). Finally, low energy (several eV) plasma-driven permeation (PDP) of D through Cu and its alloys has been demonstrated. Significant enhancement in D permeation flux compared with that of GDP has been measured.

  10. Deuterium and hydrogen flows in the thermosphere

    NASA Technical Reports Server (NTRS)

    Breig, E. L.; Hanson, W. B.

    1991-01-01

    Processes that affect vertical distributions and flows of deuterium and hydrogen between 100 and 500 km in the daytime thermosphere are investigated using a steady state numerical model that includes HD and H2 molecular flows, relevant chemistry, and transport by both molecular and eddy diffusion. The results of calculations indicate that the outward thermospheric fuxes and, hence, the planetary loss rates for D must be large compared to evaporative escape (as is also the case for H), confirming the suggestion of Breig et al. (1987). Results of measurements of H in the mesosphere and lower thermosphere and of H and D in the thermosphere were used to derive upward fluxes through the daytime thermosphere, showing that the upward fluxes exceeded the corresponding Jeans evaporative escape rates by factors of about 5 for H, and greater than 500 for D.

  11. Deuterium fractionation in the Horsehead edge

    NASA Astrophysics Data System (ADS)

    Pety, J.; Goicoechea, J. R.; Hily-Blant, P.; Gerin, M.; Teyssier, D.

    2007-03-01

    Context: Deuterium fractionation is known to enhance the [ DCO^+] /[ HCO^+] abundance ratio over the D/H ˜ 10-5 elemental ratio in the cold and dense gas typically found in pre-stellar cores. Aims: We report the first detection and mapping of very bright DCO^+J=3-2 and J=2-1 lines (3 and 4 K respectively) towards the Horsehead photodissociation region (PDR) observed with the IRAM-30m telescope. The DCO+ emission peaks close to the illuminated warm edge of the nebula (<50'' or ~0.1 pc away). Methods: Detailed nonlocal, non-LTE excitation and radiative transfer analyses have been used to determine the prevailing physical conditions and to estimate the DCO+ and H13CO+ abundances from their line intensities. Results: A large [ DCO^+] /[ HCO^+] abundance ratio (≥0.02) is inferred at the DCO+ emission peak, a condensation shielded from the illuminating far-UV radiation field where the gas must be cold (10-20 K) and dense (≥ 2 × 105 cm-3). DCO+ is not detected in the warmer photodissociation front, implying a lower [ DCO^+] /[ HCO^+] ratio (<10-3). Conclusions: .According to our gas phase chemical predictions, such a high deuterium fractionation of HCO+ can only be explained if the gas temperature is below 20 K, in good agreement with DCO+ excitation calculations. Based on observations obtained with the IRAM Plateau de Bure interferometer and 30 m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).

  12. The deuterium content of water in some volcanic glasses

    USGS Publications Warehouse

    Friedman, I.; Smith, R.L.

    1958-01-01

    The deuterium-hydrogen composition (relative to Lake Michigan water = 0.0) of water extractsd from coexisting perlite and obsidian from eleven different localities was determined. The water content of the obsidians is generally from 0.09 to 0.29 per cent by weight, though two samples from near Olancha, California, contain about 0.92 per cent. The relative deuterium concentration is from -4.6 to -12.3 per cent. The coexisting perlite contains from 2.0 to 3.8 per cent of water with a relative deuterium concentration of -3.1 to -16.6 per cent. The deuterium concentration in the perlites is not related to that in the enclosed obsidian. The deuterium concentration in the perlite water is related to the deuterium concentration of the modern meteoric water and the perlite water contains approximately 4 per cent less deuterium than does the groundwater of the area in which the perlites occur. The above relations hold true for perlites from northern New Mexico, east slope of the Sierra Nevada. California Coast Range, Yellowstone Park, Wyoming, and New Zealand. As the water in the obsidian is unrelated to meteoric water, but the enclosing perlite water is related, we believe that this is evidence for the secondary hydration of obsidian to form high water content perlitic glass. ?? 1958.

  13. Method for measuring deuterium in erbium deuteride films

    SciTech Connect

    Brangan, J.R.; Thornberg, S.M.; Keenan, M.R.

    1997-09-01

    Determining the quantity of deuterium in an erbium deuteride (ErD{sub 2}) film is essential for assessing the quality of the hydriding process but is a challenging measurement to make. First, the ideal gas law cannot be applied directly due to high temperature (950{degrees}C) and low temperature (25{degrees}C) regions in the same manifold. Additionally, the metal hydride does not release all of the deuterium rapidly upon heating and metal evaporation occurs during extended heating periods. Therefore, the method developed must provide a means to compensate for temperature inhomogeneities and the amount of deuterium retained in the metal film while heating for a minimal duration. This paper presents two thermal desorption methods used to evaluate the kinetics and equilibria of the deuterium desorption process at high temperatures (950{degrees}C). Of primary concern is the evaluation of the quantity of deuterium remaining in these films at the high temperature. A multiple volume expansion technique provided insight into the kinetics of the deuterium evolution and metal evaporation from the film. Finally a repeated pump-down approach yielded data that indicated approximately 10% of the deuterium is retained in the metal film at 950{degrees}C and approximately 1 Torr pressure. When the total moles of deuterium determined by this method were divided by the moles of erbium determined by ICP/AES, nearly stochiometric values of 2:1 were obtained for several erbium dideuteride films. Although this work presents data for erbium and deuterium, these methods are applicable to other metal hydrides as well.

  14. Deuterium Equation-of-State Experiments on Nike

    NASA Astrophysics Data System (ADS)

    Mostovych, Andrew; Bates, J. W.; Brown, D.; Karasik, M.; Schmitt, A. J.; Weaver, J.; Velikovich, A. L.; Gardner, J. H.

    2002-11-01

    Experiments to measure the primary Hugoniot equation of state of deuterium in the pressure range of 0.5 to 1.5 Mbar are being conducted on the Nike laser facility. Previous experiments [1,2,3] have yielded conflicting data on the nature of the primary shock Hugoniot and the extent of compressibility of deuterium at high pressure. Current experiments are aimed at providing data to help resolve this discrepancy. The experiment uses the Nike laser to drive an aluminum pusher plate into liquid deuterium and to launch a steady shock in the deuterium. The primary Hugoniot is determined from the particle and shock velocities in the deuterium sample. Impedance matching between the releasing aluminum and shocked deuterium determines the particle velocity whereas the shock velocity is measured directly. Special targets employ a stepped aluminum pusher to measure the aluminum pressure before release into the deuterium and masked witness plates record the time-of-flight velocity of the deuterium shocks as they travel from the pusher to the witness plate. Data are analyzed assuming that the aluminum release curves are well represented by the SESAME EOS. In the range of 0.5-0.75 Mbar, initial data show higher compressibility in deuterium than is predicted by SESAME but relatively good agreement at higher pressures. 1. L.B. DaSilva et al., Phys. Rev. Lett. 78, 483 (1997). 2. A.N. Mostovych et al., Phys. Rev. Lett. 85, 3870 (2000). 3. M. D. Knudson, et al., Phys. Rev. Lett. 87, 225501-1

  15. Observations of interstellar hydrogen and deuterium toward Alpha Centauri A

    NASA Technical Reports Server (NTRS)

    Landsman, W. B.; Henry, R. C.; Moos, H. W.; Linsky, J. L.

    1984-01-01

    A composite profile is presented of the Ly-alpha emission line of Alpha Cen A, obtained from 10 individual spectra with the high-resolution spectrograph aboard the International Ultraviolet Explorer (IUE) satellite. There is excellent overall agreement with two previous Copernicus observations. Interstellar deuterium is detected, and a lower limit is set on the deuterium to hydrogen ratio of nDI/nHI greater than 8 x 10 to the -6th. In addition, the deuterium bulk velocity appears blueshifted by 8 + or - 2 km/s with respect to interstellar hydrogen, suggesting a nonuniform medium along the line of sight.

  16. An eco-friendly N-sulfonylation of amines using stable and reusable Zn-Al-hydrotalcite solid base catalyst under ultrasound irradiation.

    PubMed

    Mokhtar, M; Saleh, T S; Ahmed, N S; Al-Thabaiti, S A; Al-Shareef, R A

    2011-01-01

    Synthetic nanosized Zn-Al-hydrotalcite (Zn-Al-HT) with 20 nm crystallite size and 61 m(2)/g BET-surface area is found to be a mild and efficient catalyst for N-sulfonylation of amines in quantitative yields under ultrasound irradiation. Exclusive synthesis of sulfonamides, using Zn-Al-HT, under ultrasound irradiation, was realized by compatible basic sites of catalyst used. The products were isolated after simple work-up in high yields and purity. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Characterization of photo-intermediates in the photo-reaction pathways of a bacteriorhodopsin Y185F mutant using in situ photo-irradiation solid-state NMR spectroscopy.

    PubMed

    Oshima, Kyosuke; Shigeta, Arisu; Makino, Yoshiteru; Kawamura, Izuru; Okitsu, Takashi; Wada, Akimori; Tuzi, Satoru; Iwasa, Tatsuo; Naito, Akira

    2015-09-26

    Photo-reaction pathways of a bacteriorhodopsin Y185F mutant were examined using in situ photo-irradiation solid-state NMR spectroscopy. (13)C CP MAS NMR spectra were recorded at -40 °C in the dark (D1), under irradiation with 520 nm light (L1), subsequently in the dark (D2), and again under irradiation with 520 nm light (L2). In the process from D1 to L1, the 13-cis, 15-syn (CS; bR548) state changed to a CS*- (13-cis, 15-syn) intermediate, which was highly stable at -40 °C, and the all-trans (AT; bR568) state transformed to an N-intermediate. Under the D2 conditions, the N-intermediate transformed to an O-intermediate, which was highly stable at -40 °C in the dark. During subsequent irradiation with 520 nm light (L2), the O-intermediate transformed to the N-intermediate through the AT state, whereas the CS*-intermediate did not change. The CS*-intermediate was converted to the AT state (or O-intermediate) after the temperature was increased to -20 °C. Upon subsequent increase of the temperature to 20 °C, the AT state (or O-intermediate) was converted to the CS state until reaching equilibrium. In this experiment, the chemical shift values of [20-(13)C, 14-(13)C]retinal provided the 13C[double bond, length as m-dash]C and 15C[double bond, length as m-dash]N configurations, respectively. From these data, the configurations of the AT and CS states and the CS*-, N-, and O-intermediates were determined to be (13-trans, 15-anti), (13-cis, 15-syn), (13-cis, 15-syn), (13-cis, 15-anti), and (13-trans, 15-anti), respectively. (13)C NMR signals of the CS*- and O-intermediates were observed for the first time for the Y185F bR mutant by in situ photo-irradiation solid-state NMR spectroscopy and the configuration of the CS*-intermediate was revealed to be significantly twisted from that of the CS state although both were assigned as (13-cis, 15-syn) configurations.

  18. Cytology is advanced by studying effects of deuterium environment

    NASA Technical Reports Server (NTRS)

    Bose, S.; Crespi, H. L.; Flaumenhaft, E.; Katz, J. J.

    1967-01-01

    Research of deuterium effects on biological systems shows deuteriation is not incompatible with life. With the successful cultivation of deuteriated bacteria, work is now being done on extraction of deuterio-compounds from bacteria.

  19. Laser induced neutron production by explosion of the deuterium clusters

    SciTech Connect

    Holkundkar, Amol R.; Mishra, Gaurav Gupta, N. K.

    2014-01-15

    The high energy deuterium ions serve as compact source of neutrons when fused with either deuterium or tritium atoms. In view of this, the explosion of the deuterium clusters under the influence of the laser pulse with intensity ranging from 10{sup 15} to 10{sup 19} W/cm{sup 2} is being studied along with the effect of the cluster radius and inter-cluster distance. The objective of this article is to study the efficiency of the deuterium cluster as a compact source of neutrons under various laser and cluster parameters. It is being observed that the cluster density (number of clusters per unit volume) is quite important to gain high neutron yield.

  20. Calculations of ion-molecule deuterium fractionation reactions involving HD

    NASA Technical Reports Server (NTRS)

    Maluendes, Sergio A.; Mclean, A. D.; Herbst, Eric

    1992-01-01

    Gas-phase chemical models of deuterium fractionation in dense interstellar clouds utilize a small number of exothermic reactions to achieve fractionation. Although HD is a major repository of deuterium, it appears not to exchange deuterium with many molecular ions. Useful semiquantitative reasons have been given for the unusual lack of reactivity of exothermic ion-HD deuterium exchange systems, but quantum chemical studies are needed to understand these ideas in more detail and to determine if the lack of reactivity pertains at very low temperatures not studied in the laboratory, or whether tunneling can drive the reactions. Accordingly, the potential energy surfaces of three representative ion-molecule exchange reactions involving protonated ions and HD have been investigated with ab initio quantum chemical techniques. Our results generally confirm the semiquantitative picture as to which reactions are likely to occur and show that tunneling at low temperatures is unlikely to alter this picture.

  1. Calculations of ion-molecule deuterium fractionation reactions involving HD

    NASA Technical Reports Server (NTRS)

    Maluendes, Sergio A.; Mclean, A. D.; Herbst, Eric

    1992-01-01

    Gas-phase chemical models of deuterium fractionation in dense interstellar clouds utilize a small number of exothermic reactions to achieve fractionation. Although HD is a major repository of deuterium, it appears not to exchange deuterium with many molecular ions. Useful semiquantitative reasons have been given for the unusual lack of reactivity of exothermic ion-HD deuterium exchange systems, but quantum chemical studies are needed to understand these ideas in more detail and to determine if the lack of reactivity pertains at very low temperatures not studied in the laboratory, or whether tunneling can drive the reactions. Accordingly, the potential energy surfaces of three representative ion-molecule exchange reactions involving protonated ions and HD have been investigated with ab initio quantum chemical techniques. Our results generally confirm the semiquantitative picture as to which reactions are likely to occur and show that tunneling at low temperatures is unlikely to alter this picture.

  2. Influence of beryllium carbide formation on deuterium retention and release

    NASA Astrophysics Data System (ADS)

    Porosnicu, C.; Anghel, A.; Sugiyama, K.; Krieger, K.; Roth, J.; Lungu, C. P.

    2011-08-01

    The inconel cladding tiles of the ITER-like-wall to be tested at JET will be coated by a beryllium layer. Carbon containing tiles will be also present. These materials are sputtered in the high flux (1022 m-2 s-1 or higher) of the deuterium-tritium plasma. Ionized by the energetic electrons and with hydrogen isotope ions they will be implanted or re-deposited, creating composite layers.In order to study the deuterium retention and release, mixed layers were prepared using the thermionic arc method.Deuterium implantation was performed using a high current ion source at room temperature using a deuterium ion beam with energy of 200 eV/D. Thermal Desorption Spectroscopy (TDS) analyses were correlated with the beryllium/carbon relative concentrations of the prepared films. At higher carbon concentrations the peak value from TDS spectra corresponding to beryllium was lower and an increased peak corresponding to the carbon was observed.

  3. Pion Induced Pion Production on Deuterium.

    NASA Astrophysics Data System (ADS)

    Sossi, Vesna

    This thesis describes measurements of the pion induced pion production reaction pi^+ d to pi^{+} pi^{-}p p performed with a 280 MeV incident pi^{+} beam at TRIUMF. The data are compared with an improved version of the Oset and Vicente-Vacas theoretical model (12). The goal of the experiment and of the analysis was to provide a larger body of data for the free reaction and to test the validity of theoretical models. In the process, the ability to determine the values of the coupling constants C, f_Delta, g _{N*Delta_tau} within such a model framework would be explored. The knowledge of the precise value of these coupling constants would constrain N^* decay branching ratios and other pion induced reaction mechanisms like Double Charge Exchange. A previous experiment (23) had indicated that the pion induced pion production on deuterium is essentially a quasifree process with the reaction occurring on the neutron leaving the proton merely a spectator. The main difference with respect to the free reaction is the effect of Fermi motion of the neutron. Although we were interested in studying the free reaction (pi^ {-}p to pi^ {+}pi^{-}n), we chose a deuterium target so that the experiment could be run with a pi^+beam, since the pi^- beam flux is about 6 times lower than the flux of the positive pion beam at 280 MeV, the energy at which our experiment was performed. Such a flux would have required a much longer running time for the experiment in order to achieve the same statistical accuracy. The quasifree nature of the process was also confirmed in our experiment. This experiment involved a coincidence measurement of the quasifree process and as such provided four-fold differential cross section spectra of the reaction thus allowing for a microscopic comparison between data and theoretical models. In the theoretical description we incorporated additional amplitudes for the N^* to N(pipi)_{p-wave} diagrams required to describe the reaction cross section at T_pi = 280 Me

  4. Combinatorial synthesis of deuterium-enriched (S)-oxybutynin.

    PubMed

    Li, Feng; Jiang, Wenfeng; Czarnik, Anthony W; Li, Wenbao

    2016-08-01

    The concept of deuterium enrichment has gained more attention due to its advantages in the studies of clinical pharmacokinetics and metabolic profiles. In addition, it is cost and time efficient to develop deuterium-enriched drugs. Herein we built a combinatorial library of deuterated (S)-oxybutynins which all 8 D-compounds were characterized by MS, [Formula: see text] NMR and [Formula: see text]C NMR.

  5. Depth profiling of deuterium using nuclear reaction analysis

    NASA Astrophysics Data System (ADS)

    Hughes, I. G.; Behrisch, R.; Martinelli, A. P.

    1993-06-01

    We report on a method to measure the depth profile of deuterium up to a depth of 7 μm in a carbon/beryllium layer using the D( 3He, p) 4He nuclear reaction in a resonance-like technique. The deuterium depth profile is determined from a measurement of the proton yield as a function of incident 3He ion energy for a limiter tile from the Joint European Torus (JET) tokamak.

  6. Depth profiling of deuterium in a beryllium/carbon layer

    NASA Astrophysics Data System (ADS)

    Hughes, I. G.; Behrisch, R.; Martinelli, A. P.

    1992-02-01

    Depth distributions for deuterium trapped within the Be/C layer on a JET limiter after long-term operation have been measured up to a depth of 7 μm using the D( 3He, p) 4He reaction in a resonance-like technique. For several points along a JET limiter tile, depth profiles and the total amount of trapped deuterium have been determined.

  7. Purification and Low Temperature (15 MK-10 k) NMR of Ultra Pure Ortho-Deuterium

    NASA Astrophysics Data System (ADS)

    Yucel, Sermet

    1988-06-01

    Pure solid ortho-deuterium, whose spin-lattice relaxation time in the liquid helium region is expected to be the order of days, is a promising candidate for nuclear spin polarized fusion fuels and targets for high energy physics applications. For purification of ortho-deuterium by conversion of para-deuterium, we present here a new catalytic technique in which conversion takes place in the physisorbed phase on copper powder or on grafoil at temperatures between 12 and 8 K. This catalysis has yielded an ortho-D_2 purity in which para -D_2 concentration is reduced to 1.1 times 10^{ -3}, better by more than an order of magnitude than in any previous work. By subsequent aging of the purified samples at 4.2 K for about 9 months, o-D _2 with residual p-D_2 concentration of 5 +/- 2 times 10^{-5} was attained, whose spin-lattice relaxation time at 1.2 K in a 0.3 T magnetic field is 11 hours. A theory of ortho -para conversion on clean metal surfaces due to interaction with conduction electrons is given. In the case of grafoil, the conversion rates in 2-D solid phases of physisorbed D_2 by emission of one and two photons (of the D_2 solid) are calculated. A temperature independent conversion rate is predicted and is consistent with our measurements in the 2-D solid regime. A sample of moderately pure o-D_2, (p-D_2 concentration of 0.004), chosen for acceptable heat of conversion as well as relatively short spin-lattice relaxation time even in the mK region, was cooled in our dilution refrigerator to 15 mK, a record low temperature for solid hydrogens. The special NMR probe and sample chamber designed and constructed for this purpose is described. With our present apparatus (magnetic field of 13 Tesla), protein polarizations of about 70% are attainable, from which deuteron polarizations in excess of 50% can be driven by dynamic polarization techniques in an o-D _2-HD mixture.

  8. Ultra-dense deuterium and cold fusion claims

    NASA Astrophysics Data System (ADS)

    Winterberg, F.

    2010-06-01

    An attempt is made to explain the recently reported occurrence of 14 MeV neutron induced nuclear reactions in deuterium metal hydrides as the manifestation of a slightly radioactive ultra-dense form of deuterium, with a density of 130,000 g/cm 3 observed by a Swedish research group through the collapse of deuterium Rydberg matter. In accordance with this observation it is proposed that a large number of deuterons form a “linear-atom” supermolecule. By the Madelung transformation of the Schrödinger equation, the linear deuterium supermolecule can be described by a quantized line vortex. A vortex lattice made up of many such supermolecules is possible only with deuterium, because deuterons are bosons, and the same is true for the electrons, which by the electron-phonon interaction in a vortex lattice form Cooper pairs. It is conjectured that the latent heat released by the collapse into the ultra-dense state has been misinterpreted as cold fusion. Hot fusion though, is here possible through the fast ignition of a thermonuclear detonation wave from a hot spot made with a 1 kJ 10 petawatt laser in a thin slice of the ultra-dense deuterium.

  9. Correlation between the band positions of (SrTiO3)1-x.(LaTiO2N)x solid solutions and photocatalytic properties under visible light irradiation.

    PubMed

    Luo, Wenjun; Li, Zhaosheng; Jiang, Xiaojun; Yu, Tao; Liu, Lifei; Chen, Xinyi; Ye, Jinhua; Zou, Zhigang

    2008-11-28

    N-doped SrTiO3 and (SrTiO3)1-x.(LaTiO2N)x samples were prepared by the thermal ammonolysis method. The photocatalytic activities of the samples were investigated in a water suspension system. Aqueous methanol solution (50 mL CH3OH + 220 mL H2O) for H2 evolution and aqueous silver nitrate solution (270 mL, 0.01 mol L(-1)) for O2 evolution were used as sacrificial reagents. The oxynitrides showed photocatalytic activities under visible light irradiation. The maximum rates of photocatalytic hydrogen and oxygen evolution under visible light irradiation (lambda > 420 nm) were 10 and 8 micromol h(-1), respectively. The samples were characterized by X-ray diffractometry, UV-Vis spectrophotometry, Fourier transform infrared spectrometry, and laser Raman spectroscopy. The unit cell edge length of (SrTiO3)1-x.(LaTiO2N)x increased linearly and their band gaps reduced from 3.18 to 2.04 eV with increasing x from 0 to 0.30. Moreover, the calculation results of (SrTiO3)0.75.(LaTiO2N)0.25 by density functional theory suggested that the band gap narrowing of the solid solutions came from the hybridization of N2p and O2p orbital. The band positions of the solid solutions were further investigated by Mott-Schottky and the onset potential method. The results suggested that the conduction band of the solid solution was lowered, which led to decrement of the hydrogen evolution rate.

  10. First measurements of deuterium-tritium and deuterium-deuterium fusion reaction yields in ignition-scalable direct-drive implosions

    DOE PAGES

    Forrest, C. J.; Radha, P. B.; Knauer, J. P.; ...

    2017-03-03

    In this study, the deuterium-tritium (D-T) and deuterium-deuterium neutron yield ratio in cryogenic inertial confinement fusion (ICF) experiments is used to examine multifluid effects, traditionally not included in ICF modeling. This ratio has been measured for ignition-scalable direct-drive cryogenic DT implosions at the Omega Laser Facility using a high-dynamic-range neutron time-of-flight spectrometer. The experimentally inferred yield ratio is consistent with both the calculated values of the nuclear reaction rates and the measured preshot target-fuel composition. These observations indicate that the physical mechanisms that have been proposed to alter the fuel composition, such as species separation of the hydrogen isotopes, aremore » not significant during the period of peak neutron production in ignition-scalable cryogenic direct-drive DT implosions.« less

  11. Comparative analysis of deuterium ions implanted and deuterium atoms saturated at high pressure in pure pd and Pd diluted alloys

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Kulikauskas, V. S.; Wiśniewski, R.; Wilczynska, T.; Kitowski, K.

    2012-01-01

    Pd and its diluted alloys (Pd-Ag, Pd-Pt, Pd-Ru, Pd-Rh) were implanted by 25 keV deuterium ions at a fluence interval of (1.2-2.3) × 1022 m-2. The same property alloys were saturated by deuterium atoms using high pressure chamber during long period with temperature stabilization and electrical resistance measurement of standard Pd wire. The post-treatment depth distributions of deuterium and accompanied hydrogen atoms were measured immediately after implantation (ten days) and after definite time period (three months) after saturation with the usage of elastic recoil detection analysis (ERDA). After two months, the measurements were repeated. The comparison of obtained results in both series of studies allowed one to make an important observation of a relative stability of deuterium and hydrogen atoms in pure Pd and its diluted alloys.

  12. Identification of Auger electron heating and inverse Auger effect in experiments irradiating solids with XUV free electron laser radiation at intensities larger than 1016 W/cm2

    NASA Astrophysics Data System (ADS)

    Rosmej, Frank B.; Petitdemange, Frédérick; Galtier, E.

    2011-09-01

    We present simulations that allow studying Auger heating and the subsequent evolution of the radiation emission of near solid density matter. Particular emphasize is paid to the multi-charge state inverse Auger-effect in dense plasmas which is proposed to explain the target emission when the conduction band at solid density becomes more atomic like as energy is transferred from the electrons to the ions. Simulations are discussed along with the first available experimental data.

  13. Helium and deuterium induced morphology on porous tungsten and effects on D retention

    NASA Astrophysics Data System (ADS)

    Kapat, Aveek; Allain, Jean Paul; Lang, Eric; Hinks, Jonathan; Donnelly, Stephen

    2016-10-01

    Tungsten is the material of choice for plasma facing components in the divertor region of future plasma-burning tokamak fusion reactors due to favorable thermo-mechanical properties. However, refractory metals are limited by possible detrimental ion-induced (He and D) surface morphologies that compromise confinement. Materials with increased defect sink domains could decrease vacancy trapping sites and decrease the probability for early-stage helium bubble formation intra-granularly. Previous work conjectured that an increase in defect sinks such as grain-boundary interfaces could provide increased resistance to helium-bubble formation. Thus higher grain boundary densities could potentially lead to an increased He fluence threshold. Based on the defect dynamics observed in the ultrafine grain tungsten, an internal free surface could also act as a defect sink and thus increases radiation tolerance, namely a material with a high surface-to-volume ratio such as porous tungsten. Moreover, very little is known about porous metals and their potential for increasing tolerance to radiation damage as a plasma-facing interface. Porous tungsten was irradiated in the MIAMI facility at the University of Huddersfield at room and 1200°C temperature with He then with D as well as just with deuterium; all cases were observed with in-situ TEM. The observed defect dynamics as well as deuterium retention are presented. This work is supported by US DOE Contract DE-SC0014267.

  14. Fragmentation and Coulomb explosion of deuterium clusters by the interaction with intense laser pulses

    SciTech Connect

    Isla, M.; Alonso, J.A.

    2005-08-15

    Experiments of Zweiback et al. [Phys. Rev. Lett. 84, 2634 (2000)] on the interaction of intense femtosecond laser pulses with a dense molecular beam of large deuterium clusters have shown that these clusters can lose most of their electrons and explode, in a process known as Coulomb explosion. The collisions between the fast deuterium (D) nuclei give rise to D-D fusion. This has motivated us to carry out computer simulations based on the time-dependent density-functional theory in order to understand the ultrafast processes occurring under these high excitations. In particular we have studied the laser irradiation of the singly charged cluster D{sub 13}{sup +}. The simulations show the occurrence of two different cluster fragmentation behaviors, depending on the intensity of the laser pulse: For not too large intensities, the cluster becomes disassembled in a slow way, whereas for large laser intensities substantial ionization takes place and a violent explosion occurs due to the electrostatic repulsion between the nuclei following the loss of the electrons by the cluster. The fast fragmentation mode fits well into the idea of the Coulomb explosion.

  15. Monitoring Photosynthetic Activity in Microalgal Cells by Raman Spectroscopy with Deuterium Oxide as a Tracking Probe.

    PubMed

    Yonamine, Yusuke; Suzuki, Yuta; Ito, Takuro; Miura, Yoshiko; Goda, Keisuke; Ozeki, Yasuyuki; Hoshino, Yu

    2017-08-14

    Microalgae offer great potential for the production of biofuel, but high photosynthetic activity is demanded for the practical realisation of microalgal biofuels. To this end, it is essential to evaluate the photosynthetic activity of single microalgal cells in a heterogeneous population. In this study, we present a method to monitor the photosynthetic activity of microalgae (in particular Euglena gracilis, a microalgal species of unicellular, photosynthetic, flagellate protists as our model organism) at single-cell resolution by Raman spectroscopy with deuterium from deuterium oxide (D2 O) as a tracking probe. Specifically, we replaced H2 O in culture media with D2 O up to a concentration of 20 % without disturbing the growth rate of E. gracilis cells and evaluated C-D bond formation as a consequence of photosynthetic reactions by Raman spectroscopy. We used the probe to monitor the kinetics of the C-D bond formation in E. gracilis cells by incubating them in D2 O media under light irradiation. Furthermore, we demonstrated Raman microscopy imaging of each single E. gracilis cell to discriminate deuterated cells from normal cells. Our results hold great promise for Raman-based screening of E. gracilis and potentially other microalgae with high photosynthetic activity by using D2 O as a tracking probe. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Deuterium on Venus: Observations from Earth

    NASA Technical Reports Server (NTRS)

    Lutz, Barry L.; Debergh, C.; Bezard, B.; Owen, T.; Crisp, D.; Maillard, J.-P.

    1991-01-01

    In view of the importance of the deuterium-to-hydrogen ratio in understanding the evolutionary scenario of planetary atmospheres and its relationship to understanding the evolution of our own Earth, we undertook a series of observations designed to resolve previous observational conflicts. We observed the dark side of Venus in the 2.3 micron spectral region in search of both H2O and HDO, which would provide us with the D/H ratio in Venus' atmosphere. We identified a large number of molecular lines in the region, belonging to both molecules, and, using synthetic spectral techniques, obtained mixing ratios of 34 plus or minus 10 ppm and 1.3 plus or minus 0.2 ppm for H2O and HDO, respectively. These mixing ratios yield a D/H ratio for Venus of D/H equals 1.9 plus or minus 0.6 times 10 (exp 12) and 120 plus or minus 40 times the telluric ratio. Although the detailed interpretation is difficult, our observations confirm that the Pioneer Venus Orbiter results and establish that indeed Venus had a period in its early history in which it was very wet, perhaps not unlike the early wet period that seems to have been present on Mars, and that, in contrast to Earth, lost much of its water over geologic time.

  17. Muon capture experiments in hydrogen and deuterium

    NASA Astrophysics Data System (ADS)

    Petitjean, Claude

    2009-02-01

    We report about new muon lifetime precision experiments at PSI to measure the singlet μp capture rate ΛS to ⩽1% and the doublet μd capture rate ΛD to ⩽1.5%. The goal is to determine precisely the induced pseudoscalar coupling gP from ΛS, and the axial two-body current term L1A from ΛD. We have developed a new hydrogen time projection chamber (TPC) operating at 10 bar as active muon stop detector. It is surrounded by cylindrical wire chambers and a plastic hodoscope as electron detector. Ultra-high purity of the hydrogen gas ( cZ<10 -7) was accomplished by continuous gas circulation and purification. Isotopic purity cd<10 -8 was achieved with a special isotope separation column. In total, ˜1.5×10 10 good events were collected which are now in final analysis. Our first result from 10% of the statistics, gP=7.3±1.1, agrees well with the theory. The μd experiment is now in development. We will use a new TPC operating in deuterium gas at T˜30 K. The proposed experimental setup is presented.

  18. Deuterium enrichment of the interstellar grain mantle

    NASA Astrophysics Data System (ADS)

    Das, Ankan; Sahu, Dipen; Majumdar, Liton; Chakrabarti, Sandip K.

    2016-01-01

    We carry out Monte Carlo simulation to study deuterium enrichments of interstellar grain mantles under various physical conditions. Based on the physical properties, various types of clouds are considered. We find that in diffuse cloud regions, very strong radiation fields persists and hardly a few layers of surface species are formed. In translucent cloud regions with a moderate radiation field, significant number of layers would be produced and surface coverage is mainly dominated by photo-dissociation products such as, C, CH3, CH2D, OH and OD. In the intermediate dense cloud regions (having number density of total hydrogen nuclei in all forms ˜2 × 104 cm-3), water and methanol along with their deuterated derivatives are efficiently formed. For much higher density regions (˜106 cm-3), water and methanol productions are suppressed but surface coverages of CO, CO2, O2 and O3 are dramatically increased. We find a very high degree of fractionation of water and methanol. Observational results support a high fractionation of methanol but surprisingly water fractionation is found to be low. This is in contradiction with our model results indicating alternative routes for de-fractionation of water. Effects of various types of energy barriers are also studied. Moreover, we allow grain mantles to interact with various charged particles (such as H+, Fe+, S+ and C+) to study the stopping power and projected range of these charged particles on various target ices.

  19. Effects of deuterium oxide on Streptococcus mutans and Pseudomonas aeruginosa.

    PubMed

    Hirai, Kaname; Tomida, Mihoko; Kikuchi, Yuichiro; Ueda, Ohmi; Ando, Hiroshi; Asanuma, Naokazu

    2010-01-01

    A complex aggregation of microorganisms growing on a solid substrate is termed a biofilm and is considered to be an etiological agents. Pseudomonas aeruginosa and Streptococcus mutans are representative bacteria in such biofilms. It is well known that deuterium oxide (D₂O) causes toxic effects on a number of biological systems. We investigated the effects of D₂O on growth and biofilm formation of P. aeruginosa and S. mutans. These bacteria were incubated in medium containing D₂O (100%, 75% or 0%) at 37°C for 24hr, 48 hr or 72 hr. Growth of P. aeruginosa was inhibited by D₂O within the first 48 hr. However, after 72 hr, growth rate was seen to increase in the D₂O-containing medium compared with in medium without D₂O. In contrast, the growth of S. mutans in the D₂O medium was inhibited within 72 hr. The biofilm formation of P. aeruginosa was increased in the D₂O medium. Biofilm formation of S. mutans in the D₂O medium increased compared with in the medium without D₂O, but this increase was only temporary in the case of P. aeruginosa. Compared to biofilm formation in 0% D₂O medium marked as 100%, the biofilm formation rate of S. mutans in 75% D₂O medium was 143% at 24 hr, 146% at 48 hr and 130% at 72 hr. In other D₂O concentration media biofilm formation was lower. In 100% D₂O medium, biofilm formation rate decreased from 114% at 24 hr to 56% at 72 hr. The biofilm formation rate of P. aeruginosa in 100% D₂O medium was 172% at 24 hr, but decreased to 88% at 72 hr. Biofilm formation of P. aeruginosa in 75% and 0% D₂O media showed no significant difference. We consider that these results were due to stress or alteration in bacterial metabolisms.

  20. Decoupling and recoupling using continuous-wave irradiation in magic-angle-spinning solid-state NMR: A unified description using bimodal Floquet theory

    SciTech Connect

    Ernst, Matthias; Samoson, Ago; Meier, Beat H.

    2005-08-08

    The application of two or more different time-dependent coherent perturbations with, in general, incommensurable frequencies occurs quite commonly in NMR experiments. Here we develop a unified description of the entire class of experiments using bimodal Floquet theory and van Vleck-Primas perturbation theory. This treatment leads to a time-independent effective Hamiltonian in Hilbert space and can be looked at as a generalization of average Hamiltonian theory to several incommensurate time dependencies. As a prototype experiment we treat the application of continuous-wave (cw) radio-frequency irradiation in combination with magic-angle sample spinning. Practically relevant examples of this type of experiments are heteronuclear spin decoupling and recoupling experiments using cw irradiation, e.g., rotary-resonance recoupling. Perturbations up to the third order must be taken into account to explain all experimentally observed resonance conditions.

  1. Measurement of High-Pressure Shock Waves in Cryogenic Deuterium-Tritium Ice Layered Capsule Implosions on NIF

    NASA Astrophysics Data System (ADS)

    Robey, H. F.; Moody, J. D.; Celliers, P. M.; Ross, J. S.; Ralph, J.; Le Pape, S.; Berzak Hopkins, L.; Parham, T.; Sater, J.; Mapoles, E. R.; Holunga, D. M.; Walters, C. F.; Haid, B. J.; Kozioziemski, B. J.; Dylla-Spears, R. J.; Krauter, K. G.; Frieders, G.; Ross, G.; Bowers, M. W.; Strozzi, D. J.; Yoxall, B. E.; Hamza, A. V.; Dzenitis, B.; Bhandarkar, S. D.; Young, B.; Van Wonterghem, B. M.; Atherton, L. J.; Landen, O. L.; Edwards, M. J.; Boehly, T. R.

    2013-08-01

    The first measurements of multiple, high-pressure shock waves in cryogenic deuterium-tritium (DT) ice layered capsule implosions on the National Ignition Facility have been performed. The strength and relative timing of these shocks must be adjusted to very high precision in order to keep the DT fuel entropy low and compressibility high. All previous measurements of shock timing in inertial confinement fusion implosions [T. R. Boehly et al., Phys. Rev. Lett. 106, 195005 (2011), H. F. Robey et al., Phys. Rev. Lett. 108, 215004 (2012)] have been performed in surrogate targets, where the solid DT ice shell and central DT gas regions were replaced with a continuous liquid deuterium (D2) fill. This report presents the first experimental validation of the assumptions underlying this surrogate technique.

  2. Measurement of high-pressure shock waves in cryogenic deuterium-tritium ice layered capsule implosions on NIF.

    PubMed

    Robey, H F; Moody, J D; Celliers, P M; Ross, J S; Ralph, J; Le Pape, S; Berzak Hopkins, L; Parham, T; Sater, J; Mapoles, E R; Holunga, D M; Walters, C F; Haid, B J; Kozioziemski, B J; Dylla-Spears, R J; Krauter, K G; Frieders, G; Ross, G; Bowers, M W; Strozzi, D J; Yoxall, B E; Hamza, A V; Dzenitis, B; Bhandarkar, S D; Young, B; Van Wonterghem, B M; Atherton, L J; Landen, O L; Edwards, M J; Boehly, T R

    2013-08-09

    The first measurements of multiple, high-pressure shock waves in cryogenic deuterium-tritium (DT) ice layered capsule implosions on the National Ignition Facility have been performed. The strength and relative timing of these shocks must be adjusted to very high precision in order to keep the DT fuel entropy low and compressibility high. All previous measurements of shock timing in inertial confinement fusion implosions [T. R. Boehly et al., Phys. Rev. Lett. 106, 195005 (2011), H. F. Robey et al., Phys. Rev. Lett. 108, 215004 (2012)] have been performed in surrogate targets, where the solid DT ice shell and central DT gas regions were replaced with a continuous liquid deuterium (D2) fill. This report presents the first experimental validation of the assumptions underlying this surrogate technique.

  3. Implications of transient changes of optical and surface properties of solids during femtosecond laser pulse irradiation to the formation of laser-induced periodic surface structures

    NASA Astrophysics Data System (ADS)

    Bonse, J.; Rosenfeld, A.; Krüger, J.

    2011-04-01

    The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of silicon wafer surfaces by linearly polarized Ti:sapphire femtosecond laser pulses (pulse duration 130 fs, central wavelength 800 nm) is studied experimentally and theoretically. In the experiments, so-called low-spatial frequency LIPSS (LSFL) were found with periods smaller than the laser wavelength and an orientation perpendicular to the polarization. The experimental results are analyzed by means of a new theoretical approach, which combines the widely accepted LIPSS theory of Sipe et al. with a Drude model, in order to account for transient (intra-pulse) changes of the optical properties of the irradiated materials. It is found that the LSFL formation is caused by the excitation of surface plasmon polaritons, SPPs, once the initially semiconducting material turns to a metallic state upon formation of a dense free-electron-plasma in the material and the subsequent interference between its electrical field with that of the incident laser beam resulting in a spatially modulated energy deposition at the surface. Moreover, the influence of the laser-excited carrier density and the role of the feedback upon the multi-pulse irradiation and its relation to the excitation of SPP in a grating-like surface structure is discussed.

  4. Negative catalytic effect of water on the reactivity of hydrogen abstraction from the C-H bond of dimethyl ether by deuterium atoms through tunneling at low temperatures

    NASA Astrophysics Data System (ADS)

    Oba, Yasuhiro; Watanabe, Naoki; Kouchi, Akira

    2016-10-01

    We report an experimental study on the catalytic effect of solid water on the reactivity of hydrogen abstraction (H-abstraction) from dimethyl ether (DME) in the low-temperature solid DME-H2O complex. When DME reacted with deuterium atoms on a surface at 15-25 K, it was efficiently deuterated via successive tunneling H-abstraction and deuterium (D)-addition reactions. The 'effective' rate constant for DME-H2O + D was found to be about 20 times smaller than that of pure DME + D. This provides the first evidence that the presence of solid water has a negative catalytic effect on tunneling H-abstraction reactions.

  5. The effect of displacement damage on deuterium retention in ITER-grade tungsten exposed to low-energy, high-flux pure and helium-seeded deuterium plasmas

    NASA Astrophysics Data System (ADS)

    Alimov, V. Kh.; Tyburska-Püschel, B.; Hatano, Y.; Roth, J.; Isobe, K.; Matsuyama, M.; Yamanishi, T.

    2012-01-01

    Samples prepared from polycrystalline ITER-grade tungsten were damaged by irradiation with 20 MeV W ions at room temperature to a fluence of 1.4 × 10 18 W/m 2. Due to the irradiation, displacement damage peaked near the end-of-range, 1.35 μm beneath the surface, at 0.89 displacements per atom. The damaged as well as undamaged W samples were then exposed to low-energy, high-flux (10 22 D/m 2 s) pure D and helium-seeded D plasmas to an ion fluence of 3 × 10 26 D/m 2 at various temperatures. Trapping of deuterium was examined by the D( 3He,p) 4He nuclear reaction at 3He energies varied from 0.69 to 4.0 MeV allowing determination of the D concentration at depths up to 6 μm. It has been found that (i) addition of 10% helium ions into the D plasma at exposure temperatures of 440-650 K significantly reduces the D concentration at depths of 0.5-6 μm compared to that for the pure plasma exposure; (ii) generation of the W-ion-induced displacement damage significantly increases the D concentration at depths up to 2 μm (i.e., in the damage zone) under subsequent exposures to both pure D and D-He plasmas.

  6. Highly Nuclear-Spin-Polarized Deuterium Atoms from the UV Photodissociation of Deuterium Iodide

    NASA Astrophysics Data System (ADS)

    Sofikitis, Dimitris; Glodic, Pavle; Koumarianou, Greta; Jiang, Hongyan; Bougas, Lykourgos; Samartzis, Peter C.; Andreev, Alexander; Rakitzis, T. Peter

    2017-06-01

    We report a novel highly spin-polarized deuterium (SPD) source, via the photodissociation of deuterium iodide at 270 nm. I (P2 3 /2) photofragments are ionized with m -state selectivity, and their velocity distribution measured via velocity-map slice imaging, from which the D polarization is determined. The process produces ˜100 % electronically polarized D at the time of dissociation, which is then converted to ˜60 % nuclear D polarization after ˜1.6 ns . These production times for SPD allow collision-limited densities of ˜1 018 cm-3 and at production rates of ˜1 021 s-1 which are 1 06 and 1 04 times higher than conventional (Stern-Gerlach separation) methods, respectively. We discuss the production of SPD beams, and combining high-density SPD with laser fusion, to investigate polarized D-T, D -He 3 , and D-D fusion.

  7. Infrared Spectra of the 2-CHLOROPROPYL Radical in Solid Para-Hydrogen

    NASA Astrophysics Data System (ADS)

    Amicangelo, Jay C.; Golec, Barbara; Lee, Yuan-Pern

    2012-06-01

    The reaction of chlorine atoms with propylene and one of its deuterium isotopomers in solid para-hydrogen (p-H2) matrices at 3.2 K has been studied using infrared spectroscopy. Irradiation at 365 nm of a co-deposited mixture of Cl2, C3H6, and p-H2 at 3.2 K produces a series of new lines in the infrared spectrum. Several of the new lines are readily assigned to the gauche and trans conformers of 1,2-dichloropropane (CH3CHClCH2Cl) resulting from the addition of two Cl atoms to C3H6. Weak lines observed at 802 and 975 cm-1 and at 813 and 981 cm-1 that become more prominent upon secondary irradiation at 254 and 214 nm are assigned to the allyl radical (C3H5) and an HCl-allyl radical complex (HCl-C3H5), respectively. Of the remaining lines, a strong line at 650 cm-1 and weaker lines at 532, 1008, 1133, 1150, 1215 and 1382 cm-1 are concluded to be due to a single carrier based on their behavior upon subsequent annealing to 4.5 K and irradiation at 254 and 214 nm. When the positions and intensities of these lines are compared to the MP2/aug-cc-pVDZ predicted vibrational spectra of the possible species that could result from the addition and abstraction reactions of one Cl atom with C3H6a, the best agreement is found with the 2-chloropropyl radical (CH3CHClCH2...). Isotopic experiments were performed with 3,3,3-C3H3D3 and the corresponding infrared peaks due to the deuterium isotopomer of this radical (CD3CHClCH2...) have also been observed. A final set of experiments were performed following irradiation of the Cl2/C3H6/p-H2 mixture at 365 nm, in which the matrix was irradiated with filtered infrared light from a globar source, which has been shown to induce a reaction between isolated Cl atoms and matrix H2 to produce HCl and H atoms. In our experiments, the major products observed after infrared irradiation are HCl, 2-chloropropane (CH3CHClCH3) and the isopropyl radical (CH3CH...CH3) and the possible mechanisms of formation of these species will be discussed. P. Brana

  8. Effect of nanostructure on radiation tolerance and deuterium retention in tungsten

    NASA Astrophysics Data System (ADS)

    Ogorodnikova, O. V.

    2017-07-01

    Understanding of radiation tolerance and hydrogen accumulation in nanomaterials is an urgent challenge since it may open new perspectives to design advanced materials for extreme conditions, for example, nuclear energy systems. In this work, intrinsic defects in nanostructured tungsten (W) films with different grain sizes were studied by decoration with deuterium (D). This method was also successfully applied to detect defects at the interface between the coating and the substrate, as well as radiation-induced defects. The build-up of D at the interface between the coating and the substrate was observed, which can be a concern for both un-irradiated and neutron-irradiated materials. It was found that the concentration of D in W materials drastically increases with decreasing mean grain size. However, the D concentration at radiation-induced defects produced by self-ion irradiation at room temperature to 3 displacements per atom is the same for all types of coatings, and it is the same as for polycrystalline W. This implies that the density of radiation-induced defects is the same for all types of W coatings, regardless of the crystalline structure of a W material. In this respect, a compromise in the development of new promising nanostructured tungsten films is necessary to ensure the radiation resistance, keeping the hydrogen concentration at an acceptable level and reducing/preventing high density of defects at the interface between the nanostructured coating and the substrate.

  9. Deuterium supersaturation in low-energy plasma-loaded tungsten surfaces

    NASA Astrophysics Data System (ADS)

    Gao, L.; Jacob, W.; von Toussaint, U.; Manhard, A.; Balden, M.; Schmid, K.; Schwarz-Selinger, T.

    2017-01-01

    Fundamental understanding of hydrogen-metal interactions is challenging due to a lack of knowledge on defect production and/or evolution upon hydrogen ingression, especially for metals undergoing hydrogen irradiation with ion energy below the displacement thresholds reported in literature. Here, applying a novel low-energy argon-sputter depth profiling method with significantly improved depth resolution for tungsten (W) surfaces exposed to deuterium (D) plasma at 300 K, we show the existence of a 10 nm thick D-supersaturated surface layer (DSSL) with an unexpectedly high D concentration of ~10 at.% after irradiation with ion energy of 215 eV. Electron back-scatter diffraction reveals that the W lattice within this DSSL is highly distorted, thus strongly blurring the Kikuchi pattern. We explain this strong damage by the synergistic interaction of energetic D ions and solute D atoms with the W lattice. Solute D atoms prevent the recombination of vacancies with interstitial W atoms, which are produced by collisions of energetic D ions with W lattice atoms (Frenkel pairs). This proposed damaging mechanism could also be active on other hydrogen-irradiated metal surfaces. The present work provides deep insight into hydrogen-induced lattice distortion at plasma-metal interfaces and sheds light on its modelling work.

  10. 1-Dodecane-sulfonic-acid-sodium-salt(LAS) assisted hydrothermal synthesis of Cd{sub x}Zn{sub 1-x}S solid solution as efficient photocatalysts under visible light irradiation

    SciTech Connect

    Jia, B.; Guo, L. J.

    2010-03-01

    With anionic surfactant LAS assisted, series of zinc cadmium sulfide semiconductor photocatalysts were synthesized by hydrothermal method. These products were characterized by X-ray diffraction (XRD), UV-Vis absorption spectra (UV-Vis) and scanning electron microscopy (FESEM). The photocatalytic activities of as-prepared samples were evaluated by photocatalytic hydrogen production from water under visible-light irradiation. The best synthesis parameters are: Composition 0.9:0.1 (Cd:Zn molar ratio), Temperature 160 deg. C, Hydrothermal Time 48 Hour, LAS Concentration 1.7 mmol/L, the maximum visible-light-catalytic hydrogen production rate is 161.25 {mu}mol/h (lambda>430 nm) which is higher than those of by coprecipitation method. The experiment results indicate that surfactant assisted hydrothermal method is an effective way to get highly active CdZnS solid solution photocatalyst.

  11. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS

    SciTech Connect

    Clark, E.

    2011-09-22

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Polymeric materials become damaged by exposure over time to ionizing radiation. Despite the limited lifetime, polymers have unique engineering material properties and polymers continue to be used in tritium handling systems. In tritium handling systems, polymers are employed mainly in joining applications such as valve sealing surfaces (eg. Stem tips, valve packing, and O-rings). Because of the continued need to employ polymers in tritium systems, over the past several years, programs at the Savannah River National Laboratory have been studying the effect of tritium on various polymers of interest. In these studies, samples of materials of interest to the SRS Tritium Facilities (ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, Teflon{reg_sign}), Vespel{reg_sign} polyimide, and the elastomer

  12. Applications of Floquet-Magnus expansion, average Hamiltonian theory and Fer expansion to study interactions in solid state NMR when irradiated with the magic-echo sequence.

    PubMed

    Mananga, Eugene Stephane

    2013-01-01

    This work presents the possibility of applying the Floquet-Magnus expansion and the Fer expansion approaches to the most useful interactions known in solid-state nuclear magnetic resonance using the magic-echo scheme. The results of the effective Hamiltonians of these theories and average Hamiltonian theory are presented. © 2013 Elsevier Inc. All rights reserved.

  13. Applications of Floquet-Magnus expansion, average Hamiltonian theory and Fer expansion to study interactions in solid state NMR when irradiated with the magic-echo sequence

    PubMed Central

    Mananga, Eugene Stephane

    2015-01-01

    This work presents the possibility of applying the Floquet-Magnus expansion and the Fer expansion approaches to the most useful interactions known in solid-state nuclear magnetic resonance using the magic-echo scheme. The results of the effective Hamiltonians of these theories and average Hamiltonian theory are presented. PMID:24034855

  14. Subsurface deuterium bubble formation in W due to low-energy high flux deuterium plasma exposure

    NASA Astrophysics Data System (ADS)

    Jia, Y. Z.; Liu, W.; Xu, B.; Qu, S. L.; Shi, L. Q.; Morgan, T. W.

    2017-03-01

    The deuterium (D) bubbles formed in W exposed to high flux D plasma were researched by scanning electron microscopy and transmission electron microscopy. After D plasma exposure at 500 K and 1000 K, a layer of nano-sized bubbles were homogenously distributed in W subsurface region. The D bubbles were homogenously nucleated due to the high D concentration, and the nucleation process is not related to the vacancy defects. At low temperature (500 K), D bubbles can grow by surface blistering, which caused different nano scale morphologies on different surfaces. At high temperature (1000 K), D bubbles mainly grow by vacancy clustering, which caused pinholes on the surface.

  15. Rapid Analysis of Protein Structure and Dynamics by Hydrogen/Deuterium Exchange Mass Spectrometry

    PubMed Central

    Hamuro, Yoshitomo; Coales, Stephen J.; Southern, Mark R.; Nemeth-Cawley, Jennifer F.; Stranz, David D.; Griffin, Patrick R.

    2003-01-01

    An automated approach for the rapid analysis of protein structure has been developed and used to study acid-induced conformational changes in human growth hormone. The labeling approach involves hydrogen/deuterium exchange (H/D-Ex) of protein backbone amide hydrogens with rapid and sensitive detection by mass spectrometry (MS). Briefly, the protein is incubated for defined intervals in a deuterated environment. After rapid quenching of the exchange reaction, the partially deuterated protein is enzymatically digested and the resulting peptide fragments are analyzed by liquid chromatography mass spectrometry (LC-MS). The deuterium buildup curve measured for each fragment yields an average amide exchange rate that reflects the environment of the peptide in the intact protein. Additional analyses allow mapping of the free energy of folding on localized segments along the protein sequence affording unique dynamic and structural information. While amide H/D-Ex coupled with MS is recognized as a powerful technique for studying protein structure and protein–ligand interactions, it has remained a labor-intensive task. The improvements in the amide H/D-Ex methodology described here include solid phase proteolysis, automated liquid handling and sample preparation, and integrated data reduction software that together improve sequence coverage and resolution, while achieving a sample throughput nearly 10-fold higher than the commonly used manual methods. PMID:13678147

  16. Hydrogen and deuterium internal friction behavior in vanadium-niobium alloys

    SciTech Connect

    Kim, Seon Jin

    1988-07-01

    Internal friction behavior of hydrogen in vanadium-niobium alloys containing from 40 at. pct. niobium to 100 at. pct. niobium as a function of hydrogen concentrations was investigated. The internal friction measurements were performed in an electrostatic drive and detection apparatus for rods in flexural vibration in the temperature range from 30/degree/K to 290/degree/K. An internal friction peak due to hydrogen was found in all the vanadium-niobium alloys. The peak was considered to be due to the jumps of hydrogen atoms in solid solution. The peak moved toward lower temperatures with increasing hydrogen concentration. In other words, the activation energies of the hydrogen motion responsible for the internal friction peaks decreased with increasing hydrogen concentration. The activation energies and /tau//sub 0/ values for the hydrogen internal friction processes obtained from the present study were compared to those obtained from long range diffusion experiments. In order to examine the isotope effect, internal friction of deuterium in the same alloys were measured and compared to those of hydrogen. Effects of oxygen on the internal friction behavior of hydrogen and deuterium were also investigated. 45 refs., 23 figs., 9 tabs.

  17. Shock timing measurements and analysis in deuterium-tritium-ice layered capsule implosions on NIF

    SciTech Connect

    Robey, H. F.; Celliers, P. M.; Moody, J. D.; Sater, J.; Parham, T.; Kozioziemski, B.; Dylla-Spears, R.; Ross, J. S.; LePape, S.; Ralph, J. E.; Dewald, E. L.; Berzak Hopkins, L.; Kroll, J. J.; Yoxall, B. E.; Hamza, A. V.; Landen, O. L.; Edwards, M. J.; Hohenberger, M.; Boehly, T. R.; Nikroo, A.

    2014-02-15

    Recent advances in shock timing experiments and analysis techniques now enable shock measurements to be performed in cryogenic deuterium-tritium (DT) ice layered capsule implosions on the National Ignition Facility (NIF). Previous measurements of shock timing in inertial confinement fusion implosions [Boehly et al., Phys. Rev. Lett. 106, 195005 (2011); Robey et al., Phys. Rev. Lett. 108, 215004 (2012)] were performed in surrogate targets, where the solid DT ice shell and central DT gas were replaced with a continuous liquid deuterium (D2) fill. These previous experiments pose two surrogacy issues: a material surrogacy due to the difference of species (D2 vs. DT) and densities of the materials used and a geometric surrogacy due to presence of an additional interface (ice/gas) previously absent in the liquid-filled targets. This report presents experimental data and a new analysis method for validating the assumptions underlying this surrogate technique. Comparison of the data with simulation shows good agreement for the timing of the first three shocks, but reveals a considerable discrepancy in the timing of the 4th shock in DT ice layered implosions. Electron preheat is examined as a potential cause of the observed discrepancy in the 4th shock timing.

  18. Shock timing measurements and analysis in deuterium-tritium-ice layered capsule implosions on NIF

    NASA Astrophysics Data System (ADS)

    Robey, H. F.; Celliers, P. M.; Moody, J. D.; Sater, J.; Parham, T.; Kozioziemski, B.; Dylla-Spears, R.; Ross, J. S.; LePape, S.; Ralph, J. E.; Hohenberger, M.; Dewald, E. L.; Berzak Hopkins, L.; Kroll, J. J.; Yoxall, B. E.; Hamza, A. V.; Boehly, T. R.; Nikroo, A.; Landen, O. L.; Edwards, M. J.

    2014-02-01

    Recent advances in shock timing experiments and analysis techniques now enable shock measurements to be performed in cryogenic deuterium-tritium (DT) ice layered capsule implosions on the National Ignition Facility (NIF). Previous measurements of shock timing in inertial confinement fusion implosions [Boehly et al., Phys. Rev. Lett. 106, 195005 (2011); Robey et al., Phys. Rev. Lett. 108, 215004 (2012)] were performed in surrogate targets, where the solid DT ice shell and central DT gas were replaced with a continuous liquid deuterium (D2) fill. These previous experiments pose two surrogacy issues: a material surrogacy due to the difference of species (D2 vs. DT) and densities of the materials used and a geometric surrogacy due to presence of an additional interface (ice/gas) previously absent in the liquid-filled targets. This report presents experimental data and a new analysis method for validating the assumptions underlying this surrogate technique. Comparison of the data with simulation shows good agreement for the timing of the first three shocks, but reveals a considerable discrepancy in the timing of the 4th shock in DT ice layered implosions. Electron preheat is examined as a potential cause of the observed discrepancy in the 4th shock timing.

  19. Selective deuterium ion acceleration using the Vulcan petawatt laser

    NASA Astrophysics Data System (ADS)

    Krygier, A. G.; Morrison, J. T.; Kar, S.; Ahmed, H.; Alejo, A.; Clarke, R.; Fuchs, J.; Green, A.; Jung, D.; Kleinschmidt, A.; Najmudin, Z.; Nakamura, H.; Norreys, P.; Notley, M.; Oliver, M.; Roth, M.; Vassura, L.; Zepf, M.; Borghesi, M.; Freeman, R. R.

    2015-05-01

    We report on the successful demonstration of selective acceleration of deuterium ions by target-normal sheath acceleration (TNSA) with a high-energy petawatt laser. TNSA typically produces a multi-species ion beam that originates from the intrinsic hydrocarbon and water vapor contaminants on the target surface. Using the method first developed by Morrison et al. [Phys. Plasmas 19, 030707 (2012)], an ion beam with >99% deuterium ions and peak energy 14 MeV/nucleon is produced with a 200 J, 700 fs, > 10 20 W / cm 2 laser pulse by cryogenically freezing heavy water (D2O) vapor onto the rear surface of the target prior to the shot. Within the range of our detectors (0°-8.5°), we find laser-to-deuterium-ion energy conversion efficiency of 4.3% above 0.7 MeV/nucleon while a conservative estimate of the total beam gives a conversion efficiency of 9.4%.

  20. Regioselective deuterium labeling of estrone and catechol estrogen metabolites.

    PubMed

    Stack, Douglas E; Ritonya, Justin; Jakopovic, Scott; Maloley-Lewis, Brittney

    2014-12-01

    Increased exposure to estrogens and estrogen metabolites is linked with increased rates of breast, ovarian and other human cancers. Metabolism of estrogen can led to formation of electrophilic o-quinones capable of binding to DNA. In order to gain insight into the mechanism of estrogen-induced DNA damage, estrone and catechol estrogens derived from estrone, have been regioselectively labeled with deuterium at the 1-position. Estrone-1-d, estrone-1,2,4-d3, 4-hydroxyestrone-1-d and 2-hydroxyestrone-1-d have been synthesized with or without deuteriums at the 16-position. The key labeling step involves deuterated trifluoroacetic acid exchange catalyzed by t-butyl alcohol. This economical, straightforward labeling technique makes available a range of estrone compounds containing deuterium at the 1-position. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Large deuterium isotope effects and their use: a historical review.

    PubMed

    Krumbiegel, Peter

    2011-03-01

    Isotope effects are differences in the properties of the isotopes of an element resulting in different reaction rates of a corresponding compound, in equilibrium constants and in the spectra. Shortly after the discovery of stable isotopes of hydrogen, oxygen, and carbon, Jacob Bigeleisen formulated a theory of isotope effects and calculated possible maximum values. Large isotope effects of (2)H (deuterium) against (1)H (protium) were seen to possibly influence interpretations of reaction mechanisms if corresponding labelling is used. Much work was invested to ensure the safety of deuterium use in men in spite of the large isotope effect. On the other hand, large deuterium isotope effects gave rise to several practical applications. Examples are the enhancement of the stability of some technical products against oxidative and against hydrolytic degradation (oils, pharmaceuticals) as well as alterations of the detoxification metabolism of pharmaceuticals in vivo.

  2. Effects of nonequilibrium particle distributions in deuterium-tritium burning

    SciTech Connect

    Michta, David; Graziani, Frank; Luu, Thomas; Pruet, Jason

    2010-01-15

    The effects of nonequilibrium particle distributions resulting from rapid deuterium-tritium burning in plasmas are investigated using a Fokker-Planck code that incorporates small-angle Coulomb scattering, bremsstrahlung, Compton scattering, and light-ion fusion. For inertial confinement fusion environments, it is found that deviations away from Maxwellian distributions for either deuterium or tritium ions are small and result in 1% changes in the energy production rates. The deuterium and tritium effective temperatures are not equal, but differ by only about 2.5% near the time of peak burn rate. Simulations with high Z (Xe) dopants show that the dopant temperature closely tracks that of the fuel. On the other hand, fusion product ion distributions are highly non-Maxwellian, and careful treatments of energy-exchange between these ions and other particles is important for determining burn rates.

  3. Deuterium and hydrogen in the local interstellar medium

    NASA Technical Reports Server (NTRS)

    Dupree, A. K.; Baliunas, S. L.; Shipman, H. L.

    1977-01-01

    Densities of neutral hydrogen and deuterium are found from observation with the Copernicus satellite of the Ly-alpha line toward two nearby stars. The hydrogen density is 0.03 + or - 0.01 per cu cm toward Alpha Aur (Capella) and 0.20 + or - 0.05 per cu cm in the direction of Alpha Cen A, values indicating that the nearby (less than 14 pc) interstellar medium is inhomogeneous and can be of low density in certain directions. The ratios of deuterium to hydrogen - 3.9 (+5.7, -1.7) by 10 to the -5th power and 0.24 (+0.12, -0.07) by 10 to the -5th power for Alpha Aur and Alpha Cen A, respectively - suggest that variations in the deuterium abundance may exist.

  4. Ion Mobility Spectrometry-Hydrogen Deuterium Exchange Mass Spectrometry of Anions: Part 3. Estimating Surface Area Exposure by Deuterium Uptake.

    PubMed

    Khakinejad, Mahdiar; Kondalaji, Samaneh Ghassabi; Donohoe, Gregory C; Valentine, Stephen J

    2016-03-01

    Gas-phase hydrogen deuterium exchange (HDX), collision cross section (CCS) measurement, and molecular dynamics simulation (MDS) techniques were utilized to develop and compare three methods for estimating the relative surface area exposure of separate peptide chains within bovine insulin ions. Electrosprayed [M - 3H](3-) and [M - 5H](5-) insulin ions produced a single conformer type with respective collision cross sections of 528 ± 5 Å(2) and 808 ± 2 Å(2). [M - 4H](4-) ions were comprised of more compact (Ω = 676 ± 3 Å(2)) and diffuse (i.e., more elongated, Ω = 779 ± 3 Å(2)) ion conformer types. Ions were subjected to HDX in the drift tube using D2O as the reagent gas. Collision-induced dissociation was used to fragment mobility-selected, isotopically labeled [M - 4H](4-) and [M - 5H](5-) ions into the protein subchains. Deuterium uptake levels of each chain can be explained by limited inter-chain isotopic scrambling upon collisional activation. Using nominal ion structures from MDS and a hydrogen accessibility model, the deuterium uptake for each chain was correlated to its exposed surface area. In separate experiments, the per-residue deuterium content for the protonated and deprotonated ions of the synthetic peptide KKDDDDDIIKIIK were compared. The differences in deuterium content indicated the regional HDX accessibility for cations versus anions. Using ions of similar conformational type, this comparison highlights the complementary nature of HDX data obtained from positive- and negative-ion analysis.

  5. Ion Mobility Spectrometry-Hydrogen Deuterium Exchange Mass Spectrometry of Anions: Part 3. Estimating Surface Area Exposure by Deuterium Uptake

    NASA Astrophysics Data System (ADS)

    Khakinejad, Mahdiar; Ghassabi Kondalaji, Samaneh; Donohoe, Gregory C.; Valentine, Stephen J.

    2016-03-01

    Gas-phase hydrogen deuterium exchange (HDX), collision cross section (CCS) measurement, and molecular dynamics simulation (MDS) techniques were utilized to develop and compare three methods for estimating the relative surface area exposure of separate peptide chains within bovine insulin ions. Electrosprayed [M - 3H]3- and [M - 5H]5- insulin ions produced a single conformer type with respective collision cross sections of 528 ± 5 Å2 and 808 ± 2 Å2. [M - 4H]4- ions were comprised of more compact (Ω = 676 ± 3 Å2) and diffuse (i.e., more elongated, Ω = 779 ± 3 Å2) ion conformer types. Ions were subjected to HDX in the drift tube using D2O as the reagent gas. Collision-induced dissociation was used to fragment mobility-selected, isotopically labeled [M - 4H]4- and [M - 5H]5- ions into the protein subchains. Deuterium uptake levels of each chain can be explained by limited inter-chain isotopic scrambling upon collisional activation. Using nominal ion structures from MDS and a hydrogen accessibility model, the deuterium uptake for each chain was correlated to its exposed surface area. In separate experiments, the per-residue deuterium content for the protonated and deprotonated ions of the synthetic peptide KKDDDDDIIKIIK were compared. The differences in deuterium content indicated the regional HDX accessibility for cations versus anions. Using ions of similar conformational type, this comparison highlights the complementary nature of HDX data obtained from positive- and negative-ion analysis.

  6. The deuterium content of atmospheric molecular hydrogen

    NASA Astrophysics Data System (ADS)

    Gerst, Steven Gregory

    2000-09-01

    A new technique for the separation of molecular hydrogen (H2) from air and the determination of its deuterium (D) content is presented. A high-pressure air sample in an aluminum cylinder is condensed at -196°C, whereby H2 contained in the air sample is enriched in the gaseous headspace above the liquefied air. The H2-enriched headspace is bled into a vacuum extraction line where the H2 is oxidized to H2O for cryogenic isolation from the air stream. The captured water is reduced back to H2 for determination of its D/H ratio via isotope-ratio mass spectrometry (δD is reported in permil (‰) vs. Vienna Standard Mean Ocean Water, where δD = ((D/H)sample/(D/H) VSMOW - 1)*1000‰). Air samples for δD analyses were collected in November-December 1998 on a transect from Seattle, WA, 48°N, to McMurdo, Antarctica, 71°S (n = 19), and over a two-year interval on the Washington Coast, 48°N (n = 11), and Point Barrow, AK, 71°N (n = 6). Results indicate that the average δD of global atmospheric H2 is +130 +/- 4‰, with average δD values of +123 +/- 3‰ and +138 +/- 8‰ in the northern and southern hemispheres, respectively. Comparison of background and polluted samples in the Seattle area indicate the δD of H2 produced by anthropogenic activities (e.g. automobiles) is -1961 +/- 10‰. Laboratory combustion studies of pine needles and pine branches indicate that the δD of H2 emitted during biomass burning is -293 +/- 60‰. The results of field experiments (n = 6) using a large chamber to isolate a volume of air in contact with soil imply that the H2 removed during soil uptake has a δD value 57 +/- 24‰ lower than that of atmospheric H2. The constraints that these preliminary isotopic measurements place on the global H2 budget are limited by the unmeasured isotopic composition of photochemically produced H2, δDhν. However, the global H2 isotope balance implies that the average global value of δDhν must be +130‰, and this value is demonstrated to be

  7. Deuterium Nucleosynthesis in AGN: Is D Cosmological?

    NASA Astrophysics Data System (ADS)

    Lubowich, D. A.; Kuno, N.; Roberts, H.; Millar, T. J.; Henkel, C.; Pasachoff, J.; Mauersberger, R.

    2005-07-01

    Although deuterium is predicted to be primarily cosmological, D can also be produced by cosmic-ray or γ-ray spallation reactions - possibly between high energy jets and the surrounding gas in AGN. We used the Nobeyama mm array with a 3" resolution (200 pc) in April 2003 to search for any enhanced D from the DCN J = 2 1 line in the 45"×45" (3 kpc) circumnuclear region of the Seyfert galaxy NGC 1068. NGC 1068 is an optimal target because it has jets, starburst activity, a circumuclear molecular ring and molecular disk, dense optically thick concentrations of HCN, and a low-energy X-ray flux of 1042 erg/s (the highest X-ray flux of any galaxy in which HCN has been detected and the flux required to produce high D abundances). Although DCN is detected in most Galactic or LMC molecular clouds with optically thick HCN, we did not detect DCN with Srms = 11 mJy/beam or Trms = 35.6 mK. Thus our 3σ upper limits are S⩽ 33 mJy/beam or Tmb ⩽ 106.7 mK and DCN/HCN⩽ 0.0044. Using our 5260 reaction chemical network we estimate the underlying D/H⩽ 1.5×10-5 less than or equal to but not greater than the local Galactic ISM D/H = 1.5 × 10-5. Thus there is no significant D production in the nuclear region of NGC 1068 and NGC 1068 has probably not had a recent period of activity with a γ-ray or cosmic-ray luminosity > 1042 erg/s. If jet-cloud nucleosynthesis produces significant amounts of D, then the D is either produced inside a very small nuclear region or transported outside the nuclear region whereby subsequent infall may continuously supply galactic nuclei with D. However, any enhanced D produced via spallation reactions would have been destroyed via astration due to the large AGN star formation rate. Our results are additional evidence that D is primarily cosmological and that AGN do not produce D.

  8. Total integrated dose testing of solid-state scientific CD4011, CD4013, and CD4060 devices by irradiation with CO-60 gamma rays

    NASA Technical Reports Server (NTRS)

    Dantas, A. R. V.; Gauthier, M. K.; Coss, J. R.

    1985-01-01

    The total integrated dose response of three CMOS devices manufactured by Solid State Scientific has been measured using CO-60 gamma rays. Key parameter measurements were made and compared for each device type. The data show that the CD4011, CD4013, and CD4060 produced by this manufacturers should not be used in any environments where radiation levels might exceed 1,000 rad(Si).

  9. Production of tylosin in solid-state fermentation by Streptomyces fradiae NRRL-2702 and its gamma-irradiated mutant (gamma-1).

    PubMed

    Khaliq, Shazia; Rashid, Nosheen; Akhtar, Kalsoom; Ghauri, Muhammad Afzal

    2009-11-01

    To develop solid-state fermentation system (SSF) for hyper production of tylosin from a mutant gamma-1 of Streptomyces fradiae NRRL-2702 and its parent strain. Various agro-industrial wastes were screened to study their effect on tylosin production in SSF. Wheat bran as solid substrate gave the highest production of 2500 microg of tylosin g(-1) substrate by mutant gamma-1 against parent strain (300 microg tylosin g(-1) substrate). The tylosin yield was further improved to 4500 microg g(-1) substrate [70% moisture, 10% inoculum (v/w), pH 9.2, 30 degrees C, supplemental lactose and sodium glutamate on day 9]. Wild-type strain displayed less production of tylosin (655 microg of tylosin g(-1) substrate) in SSF even after optimization of process parameters. The study has shown that solid-state fermentation system significantly enhanced the tylosin yield by mutant gamma-1. This study proved to be very useful and resulted in 6.87 +/- 0.30-fold increase in tylosin yield by this mutant when compared to that of wild-type strain.

  10. Laser-driven polarized hydrogen and deuterium internal targets

    SciTech Connect

    Jones, C.E.; Fedchak, J.A.; Kowalczyk, R.S.

    1995-08-01

    After completing comprehensive tests of the performance of the source with both hydrogen and deuterium gas, we began tests of a realistic polarized deuterium internal target. These tests involve characterizing the atomic polarization and dissociation fraction of atoms in a storage cell as a function of flow and magnetic field, and making direct measurements of the average nuclear tensor polarization of deuterium atoms in the storage cell. Transfer of polarization from the atomic electron to the nucleus as a result of D-D spin-exchange collisions was observed in deuterium, verifying calculations suggesting that high vector polarization in both hydrogen and deuterium can be obtained in a gas in spin temperature equilibrium without inducing RF transitions between the magnetic substates. In order to improve the durability of the system, the source glassware was redesigned to simplify construction and installation and eliminate stress points that led to frequent breakage. Improvements made to the nuclear polarimeter, which used the low energy {sup 3}H(d,n){sup 4}He reaction to analyze the tensor polarization of the deuterium, included installing acceleration lenses constructed of wire mesh to improve pumping conductance, construction of a new holding field coil, and elimination of the Wien filter from the setup. These changes substantially simplified operation of the polarimeter and should have reduced depolarization in collisions with the wall. However, when a number of tests failed to show an improvement of the nuclear polarization, it was discovered that extended operation of the system with a section of teflon as a getter for potassium caused the dissociation fraction to decline with time under realistic operating conditions, suggesting that teflon may not be a suitable material to eliminate potassium from the target. We are replacing the teflon surfaces with drifilm-coated ones and plan to continue tests of the polarized internal target in this configuration.

  11. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS (REVISION 1)

    SciTech Connect

    Clark, E.

    2013-09-13

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Revision 1 adds a comparison with results of a study of tritium exposed EPDM. The amount of gas produced by the gamma irradiation was found to be equivalent to about 280 days exposure to initially pure tritium gas at one atmosphere. The glass transition temperature of the tritium exposed EPDM rose about 10°C. over 280 days, while no glass transition temperature change was observed for gamma irradiated EPDM. This means that gamma irradiation in deuterium cannot be used as a surrogate for tritium exposure.

  12. Calculation of Shock Hugoniot Curves of Precompressed Liquid Deuterium

    SciTech Connect

    Militzer, B

    2002-11-18

    Path integral Monte Carlo simulations have been used to study deuterium at high pressure and temperature. The equation of state has been derived in the temperature and density region of 10,000 {le} T {le} 1,000,000 and 0.6 {le} {rho} {le} 2.5 g cm{sup -3}. A series of shock Hugoniot curves is computed for different initial compressions in order to compare with current and future shock wave experiments using liquid deuterium samples precompressed in diamond anvil cells.

  13. Gas temperature measurements in deuterium hollow cathode glow discharge

    SciTech Connect

    Majstorović, Gordana; Šišović, Nikola

    2016-03-25

    We report results of optical emission spectroscopy measurements of rotational T{sub rot} and translational (gas) temperature of deuterium molecules in a hollow cathode (HC) glow discharge. The rotational temperature of excited electronic state of D{sub 2} was determined from the intensity distribution in the rotational structure of Q branch of the two Fulcher-α diagonal bands: (ν’=ν”=2) and (ν’=ν”=3). The population of excited energy levels, determined from relative line intensities, was used to derive radial rotational temperature distributions as well as gas temperature distribution of deuterium molecule.

  14. Deuterium: Natural variations used as a biological tracer

    USGS Publications Warehouse

    Gleason, J.D.; Friedman, I.

    1970-01-01

    The suggestion is made that isotope tracing be carried out by monitoring the natural variations in deuterium concentrations. As an example, the natural variations in deuterium concentrations between food and water collected in Illinois and food and water collected in Colorado were used to determine the residence time of water in the blood and urine of rats. We observed not only a 51/2-day turnover time of water in the blood and urine, but also evidence for the influx of water vapor from the atmosphere through the lungs into the blood.

  15. Commissioning status of the Continuous Wave Deuterium Demonstrator

    SciTech Connect

    Hartog, P.D.; Dooling, J.; Lorello, M.; Rathke, J.; Carwardine, J.; Godden, D.; Pile, G.; Yule, T.; Zinneman, T.

    1993-06-01

    Grumman Aerospace Corporation, Argonne National Laboratory, and Culham Laboratory are commissioning the Continuous Wave Deuterium Demonstrator (CWDD) in a facility at Argonne National Laboratory. CWDD is a high-brightness, high-current, 7.5-MeV negative deuterium accelerator. The 352-MHz rf accelerating cavities are cryogenically cooled with supercritical neon to reduce the rf power requirements. Installation of the accelerator into the Argonne facility began in May 1991, and first beam from the injector was extracted in February 1992. The accelerator and facility are described, and current status and future plans are discussed.

  16. Commissioning status of the Continuous Wave Deuterium Demonstrator

    SciTech Connect

    Hartog, P.D.; Dooling, J.; Lorello, M.; Rathke, J. ); Carwardine, J.; Godden, D.; Pile, G. ); Yule, T.; Zinneman, T. )

    1993-01-01

    Grumman Aerospace Corporation, Argonne National Laboratory, and Culham Laboratory are commissioning the Continuous Wave Deuterium Demonstrator (CWDD) in a facility at Argonne National Laboratory. CWDD is a high-brightness, high-current, 7.5-MeV negative deuterium accelerator. The 352-MHz rf accelerating cavities are cryogenically cooled with supercritical neon to reduce the rf power requirements. Installation of the accelerator into the Argonne facility began in May 1991, and first beam from the injector was extracted in February 1992. The accelerator and facility are described, and current status and future plans are discussed.

  17. Synthesis of deuterium labeled 17-methyl-testosterone

    SciTech Connect

    Shinohara, Y.; Baba, S.; Kasuya, Y.

    1984-09-01

    The synthesis of two forms of selectively deuterated 17-methyl-testosterone is described. 17-Methyl-d3-testosterone was prepared by the Grignard reaction of dehydroepiandrosterone with deuterium labeled methyl magnesium iodide followed by an Oppenauer oxidation. 17-Methyl-d3-testosterone-19,19,19-d3 was prepared by treating 3,3-ethylenedioxy-5,10-epoxy-5 alpha, 10 alpha-estran-17-one with deuterium labeled methyl magnesium bromide followed by hydrolysis and dehydration of the 5 alpha-hydroxyandrostane derivative.

  18. Transport of Recycled Deuterium to the Plasma Core in TFTR

    SciTech Connect

    Bell, M.G.; Budny, R.V.; Jassby, D.L.; Park, H.; Skinner, C.H.; et al

    1997-10-01

    We report a study of the fueling of the plasma core by recycling in the Tokamak Fusion Test Reactor (TFTR) [Phys. Plasmas 2, 2176 (1995)]. We have analyzed discharges fueled by deuterium recycled from the limiter and tritium-only neutral beam injection. In these plasmas, the DT neutron rate provides a measure of the deuterium influx into the core plasma. We find a reduced influx with plasmas using lithium pellet conditioning and with plasmas of reduced major (and minor) radius. Modeling with the DEGAS neutrals code shows that the dependence on radius can be related to the penetration of neutrals through the scrape-off layer.

  19. Transport of recycled deuterium to the plasma core in TFTR

    SciTech Connect

    Skinner, C.H.; Bell, M.G.; Budny, R.V.; Jassby, D.L.; Park, H.; Ramsey, A.T.; Stotler, D.P.; Strachan, J.D.

    1997-10-01

    The authors report a study of the fueling of the plasma core by recycling in the Tokamak Fusion Test Reactor (TFTR). They have analyzed discharges fueled by deuterium recycled from the limiter and tritium-only neutral beam injection. In these plasmas, the DT neutron rate provides a measure of the deuterium influx into the core plasma. They find a reduced influx with plasmas using lithium pellet conditioning and with plasmas of reduced major (and minor) radius. Modeling with the DEGAS neutrals code shows that the dependence on radius can be related to the penetration of neutrals through the scrape-off layer.

  20. [Research progress of the inhibitory effect of deuterium-depleted water on cancers].

    PubMed

    Wang, Hongqiang; Liu, Cong; Fang, Weiyi; Yang, Huiling

    2012-10-01

    Deuterium is an important predisposing factor for cancer. Deuterium-depleted Water, also known as low deuterium water, ultra-light water or no deuterium water, can be obtained by removing deuterium from natural water. Studies have shown that water with a low deuterium concentration (<65% percent of volume) can inhibit cancer growth. Clinical trials demonstrated that drinking DDW (10-20 ppm) caused growth arrest of malignant cells in cancer patients and significantly prolonged the patient survival with also improved quality of life. A wide range of anti-cancer drugs in current use are associated with severe adverse effects, while deuterium-depleted water appears to have virtually no pharmacological side effects and is convenient to administer. The authors review the advances in the researches of anti-cancer effects and the underlying mechanisms of deuterium-depleted water.

  1. INSTRUMENTS AND METHODS OF INVESTIGATION: Generation of high-order harmonics of high-power lasers in plasmas produced under irradiation of solid target surfaces by a prepulse

    NASA Astrophysics Data System (ADS)

    Ganeev, Rashid A.

    2009-01-01

    Research on high-order harmonic generation in laser-produced plasmas is reviewed. We analyze the conditions for the generation of harmonics (up to the 101st order, λ = 7.9 nm) in the propagation of laser radiation through a weakly ionized plasma prepared by irradiating the surfaces of different targets with a laser prepulse. We discuss the findings of investigations into the resonance intensity enhancement of individual harmonics in a number of plasma formations, which have demonstrated a substantial increase in the conversion efficiency in the plateau region of the harmonic-order distribution (in particular, of the 13th harmonic in indium plasmas with the efficiency 10-4). We review the results of investigations of harmonic generation in nanoparticle-containing plasmas. Different techniques for increasing the intensity and order of the generated harmonics are discussed.

  2. Introduction of poly(4-vinylpyridinium) perchlorate as a new, efficient, and versatile solid acid catalyst for one-pot synthesis of substituted coumarins under ultrasonic irradiation.

    PubMed

    Khaligh, Nader Ghaffari; Shirini, Farhad

    2013-01-01

    Poly(4-vinylpyridinium) perchlorate, is a supported, recyclable, eco-benign catalyst for synthesis of substituted coumarins via Pechmann reaction using ultrasound irradiation at room temperature and neat condition in high yields with short reaction times. The catalyst was studied by FT-IR, X-ray diffraction, scanning electron microscope, thermo-gravimetric and energy dispersion X-ray analyses. All the products were extensively characterized by (1)H NMR, FT-IR, MS and melting point analyses. This methodology offers momentous improvements over various options for the synthesis of coumarins with regard to yield of products, simplicity in operation and green aspects by avoiding toxic catalysts and solvents. Further, the catalyst can be reused and recovered for several times without loss of activity. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Specific features of X-ray generation by plasma focus chambers with deuterium and deuterium-tritium fillings

    NASA Astrophysics Data System (ADS)

    Dulatov, A. K.; Krapiva, P. S.; Lemeshko, B. D.; Mikhailov, Yu. V.; Moskalenko, I. N.; Prokuratov, I. A.; Selifanov, A. N.

    2016-01-01

    The process of hard X-ray (HXR) generation in plasma focus (PF) chambers was studied experimentally. The radiation was recorded using scintillation detectors with a high time resolution and thermoluminescent detectors in combination with the method of absorbing filters. Time-resolved analysis of the processes of neutron and X-ray generation in PFs is performed. The spectra of HXR emission from PF chambers with deuterium and deuterium-tritium fillings are determined. In experiments with PF chambers filled with a deuterium-tritium mixture, in addition to the HXR pulse with photon energies of up to 200-300 keV, a γ-ray pulse with photon energies of up to 2.5-3.0 MeV is recorded, and a mechanism of its generation is proposed.

  4. Laser irradiation to produce amorphous pharmaceuticals.

    PubMed

    Titapiwatanakun, Varin; Tankul, Junlathip; Basit, Abdul W; Gaisford, Simon

    2016-11-30

    Using a high-power CO2 laser to irradiate powder beds, it was possible to induce phase transformation to the amorphous state. Irradiation of a model drug, indometacin, resulted in formation of a glass. Varying the settings of the laser (power and raster speed) was shown to change the physicochemical properties of the glasses produced and all irradiated glasses were found to be more stable than a reference glass produced by melt-quenching. Irradiation of a powder blend of paracetamol and polyvinylpyrrolidone K30 was found to produce a solid amorphous dispersion. The results suggest that laser-irradiation might be a useful method for making amorphous pharmaceuticals.

  5. 10 CFR 110.24 - General license for the export of deuterium.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false General license for the export of deuterium. 110.24... MATERIAL Licenses § 110.24 General license for the export of deuterium. (a) A general license is issued to any person to export to any country not listed in § 110.28 or § 110.29 deuterium in individual...

  6. 10 CFR 110.24 - General license for the export of deuterium.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false General license for the export of deuterium. 110.24... MATERIAL Licenses § 110.24 General license for the export of deuterium. (a) A general license is issued to any person to export to any country not listed in § 110.28 or § 110.29 deuterium in individual...

  7. 10 CFR 110.24 - General license for the export of deuterium.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false General license for the export of deuterium. 110.24... MATERIAL Licenses § 110.24 General license for the export of deuterium. (a) A general license is issued to any person to export to any country not listed in § 110.28 or § 110.29 deuterium in individual...

  8. 10 CFR 110.24 - General license for the export of deuterium.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false General license for the export of deuterium. 110.24... MATERIAL Licenses § 110.24 General license for the export of deuterium. (a) A general license is issued to any person to export to any country not listed in § 110.28 or § 110.29 deuterium in individual...

  9. 10 CFR 110.24 - General license for the export of deuterium.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false General license for the export of deuterium. 110.24... MATERIAL Licenses § 110.24 General license for the export of deuterium. (a) A general license is issued to any person to export deuterium in individual shipments of 10 kilograms or less (50 kilograms of heavy...

  10. DEUTERIUM BURNING IN MASSIVE GIANT PLANETS AND LOW-MASS BROWN DWARFS FORMED BY CORE-NUCLEATED ACCRETION

    SciTech Connect

    Bodenheimer, Peter; Fortney, Jonathan J.; Saumon, Didier E-mail: gennaro.dangelo@nasa.gov E-mail: jfortney@ucolick.org

    2013-06-20

    Using detailed numerical simulations, we study the formation of bodies near the deuterium-burning limit according to the core-nucleated giant planet accretion scenario. The objects, with heavy-element cores in the range 5-30 M{sub Circled-Plus }, are assumed to accrete gas up to final masses of 10-15 Jupiter masses (M{sub Jup}). After the formation process, which lasts 1-5 Myr and which ends with a ''cold-start'', low-entropy configuration, the bodies evolve at constant mass up to an age of several Gyr. Deuterium burning via proton capture is included in the calculation, and we determined the mass, M{sub 50}, above which more than 50% of the initial deuterium is burned. This often-quoted borderline between giant planets and brown dwarfs is found to depend only slightly on parameters, such as core mass, stellar mass, formation location, solid surface density in the protoplanetary disk, disk viscosity, and dust opacity. The values for M{sub 50} fall in the range 11.6-13.6 M{sub Jup}, in agreement with previous determinations that do not take the formation process into account. For a given opacity law during the formation process, objects with higher core masses form more quickly. The result is higher entropy in the envelope at the completion of accretion, yielding lower values of M{sub 50}. For masses above M{sub 50}, during the deuterium-burning phase, objects expand and increase in luminosity by one to three orders of magnitude. Evolutionary tracks in the luminosity versus time diagram are compared with the observed position of the companion to Beta Pictoris.

  11. Deuterium Burning in Massive Giant Planets and Low-mass Brown Dwarfs Formed by Core-nucleated Accretion

    NASA Astrophysics Data System (ADS)

    Bodenheimer, Peter; D'Angelo, Gennaro; Lissauer, Jack J.; Fortney, Jonathan J.; Saumon, Didier

    2013-06-01

    Using detailed numerical simulations, we study the formation of bodies near the deuterium-burning limit according to the core-nucleated giant planet accretion scenario. The objects, with heavy-element cores in the range 5-30 M ⊕, are assumed to accrete gas up to final masses of 10-15 Jupiter masses (M Jup). After the formation process, which lasts 1-5 Myr and which ends with a "cold-start," low-entropy configuration, the bodies evolve at constant mass up to an age of several Gyr. Deuterium burning via proton capture is included in the calculation, and we determined the mass, M 50, above which more than 50% of the initial deuterium is burned. This often-quoted borderline between giant planets and brown dwarfs is found to depend only slightly on parameters, such as core mass, stellar mass, formation location, solid surface density in the protoplanetary disk, disk viscosity, and dust opacity. The values for M 50 fall in the range 11.6-13.6 M Jup, in agreement with previous determinations that do not take the formation process into account. For a given opacity law during the formation process, objects with higher core masses form more quickly. The result is higher entropy in the envelope at the completion of accretion, yielding lower values of M 50. For masses above M 50, during the deuterium-burning phase, objects expand and increase in luminosity by one to three orders of magnitude. Evolutionary tracks in the luminosity versus time diagram are compared with the observed position of the companion to Beta Pictoris.

  12. Influence of radiative processes on the ignition of deuterium-tritium plasma containing inactive impurities

    NASA Astrophysics Data System (ADS)

    Gus'kov, S. Yu.; Sherman, V. E.

    2016-08-01

    The degree of influence of radiative processes on the ignition of deuterium-tritium (DT) plasma has been theoretically studied as dependent on the content of inactive impurities in plasma. The analytic criterion of plasma ignition in inertial confinement fusion (ICF) targets is modified taking into account the absorption of intrinsic radiation from plasma in the ignition region. The influence of radiative processes on the DT plasma ignition has been analytically and numerically studied for plasma that contains a significant fraction of inactive impurities either as a result of DT fuel mixing with ICF target ablator material or as a result of using light metal DT-hydrides as solid noncryogenic fuel. It has been shown that the effect of the absorption of intrinsic radiation leads to lower impurity-induced increase in the ignition energy as compared to that calculated in the approximation of optically transparent ignition region.

  13. Theory of the spin-1 bosonic liquid metal - Equilibrium properties of liquid metallic deuterium

    NASA Technical Reports Server (NTRS)

    Oliva, J.; Ashcroft, N. W.

    1984-01-01

    The theory of a two-component quantum fluid comprised of spin-1/2 fermions and nonzero spin bosons is examined. This system is of interest because it embodies a possible quantum liquid metallic phase of highly compressed deuterium. Bose condensation is assumed present and the two cases of nuclear-spin-polarized and -unpolarized systems are considered. A significant feature in the unpolarized case is the presence of a nonmagnetic mode with quadratic dispersion owing its existence to nonzero boson spin. The physical character of this mode is examined in detail within a Bogoliubov approach. The specific heat, bulk modulus, spin susceptibility, and thermal expansion are all determined. Striking contrasts in the specific heats and thermal-expansion coefficients of the liquid and corresponding normal solid metallic phase are predicted.

  14. Development of a compact magnetic proton recoil spectrometer for measurement of deuterium-tritium neutrons

    SciTech Connect

    Zhang, Jianfu Ouyang, Xiaoping; Zhang, Xianpeng; Qiu, Suizheng; Zhang, Guoguang; Ruan, Jinlu; Zhang, Xiaodong; Yang, Shaohua; Song, Jiwen; Liu, Linyue; Li, Hongyun

    2015-12-15

    A new compact magnetic proton recoil (MPR) neutron spectrometer has been designed for precise measurement of deuterium-tritium (DT) neutrons. This design is presented emphasizing the magnetic analyzing system, which is based on a compact quadrupole-dipole (QD) electromagnet. The focal plane detector (FPD) is also discussed with respect to application for the next step. The characteristics of the MPR spectrometer were calculated by using Monte Carlo simulation. A preliminary experiment was performed to test the magnetic analyzing system and the proton images of the FPD. Since the QD electromagnet design allows for a larger foil thickness and solid angle to be utilized, the MPR spectrometer defined in this paper can achieve neutron detection efficiency more than 5 × 10{sup −7} at an energy resolution of 1.5% for measuring DT neutrons.

  15. Microstructural studies of hydrogen and deuterium in bcc refractory metals. Final technical report

    SciTech Connect

    Moss, S.C.

    1984-04-01

    Research was conducted on the microstructural atomic arrangements in alloys of hydrogen and deuterium with bcc refractory metals with emphasis on V and Nb. Because these are interstitial phases in which the host metal lattice is substantially deformed by the incorporation of the H(D) atoms, there are pronounced x-ray scattering effects. X-ray diffraction was used, with neutron scattering providing useful corollary data. One objective was to determine the phase relations, solid solution structures and phase transitions in metal-hydride alloys which depend upon the hydrogen-hydrogen interaction via the displacement field of the metal atoms. This has often included the elucidation of subtle thermodynamic properties (as in critical wetting) which are revealed in structural studies. Crystals were supplied for positron annihilation studies of the Fermi surface of H-Ta alloys which have revealed significant electronic trends. Work on alkali-graphite intercalates was initiated.

  16. Development of a compact magnetic proton recoil spectrometer for measurement of deuterium-tritium neutrons.

    PubMed

    Zhang, Jianfu; Ouyang, Xiaoping; Qiu, Suizheng; Zhang, Guoguang; Ruan, Jinlu; Zhang, Xiaodong; Zhang, Xianpeng; Yang, Shaohua; Song, Jiwen; Liu, Linyue; Li, Hongyun

    2015-12-01

    A new compact magnetic proton recoil (MPR) neutron spectrometer has been designed for precise measurement of deuterium-tritium (DT) neutrons. This design is presented emphasizing the magnetic analyzing system, which is based on a compact quadrupole-dipole (QD) electromagnet. The focal plane detector (FPD) is also discussed with respect to application for the next step. The characteristics of the MPR spectrometer were calculated by using Monte Carlo simulation. A preliminary experiment was performed to test the magnetic analyzing system and the proton images of the FPD. Since the QD electromagnet design allows for a larger foil thickness and solid angle to be utilized, the MPR spectrometer defined in this paper can achieve neutron detection efficiency more than 5 × 10(-7) at an energy resolution of 1.5% for measuring DT neutrons.

  17. Theory of the spin-1 bosonic liquid metal - Equilibrium properties of liquid metallic deuterium

    NASA Technical Reports Server (NTRS)

    Oliva, J.; Ashcroft, N. W.

    1984-01-01

    The theory of a two-component quantum fluid comprised of spin-1/2 fermions and nonzero spin bosons is examined. This system is of interest because it embodies a possible quantum liquid metallic phase of highly compressed deuterium. Bose condensation is assumed present and the two cases of nuclear-spin-polarized and -unpolarized systems are considered. A significant feature in the unpolarized case is the presence of a nonmagnetic mode with quadratic dispersion owing its existence to nonzero boson spin. The physical character of this mode is examined in detail within a Bogoliubov approach. The specific heat, bulk modulus, spin susceptibility, and thermal expansion are all determined. Striking contrasts in the specific heats and thermal-expansion coefficients of the liquid and corresponding normal solid metallic phase are predicted.

  18. Surface modification and deuterium retention in reduced-activation steels under low-energy deuterium plasma exposure. Part II: steels pre-damaged with 20 MeV W ions and high heat flux

    NASA Astrophysics Data System (ADS)

    Ogorodnikova, O. V.; Zhou, Z.; Sugiyama, K.; Balden, M.; Pintsuk, G.; Gasparyan, Yu.; Efimov, V.

    2017-03-01

    The reduced-activation ferritic/martensitic (RAFM) steels including Eurofer (9Cr) and oxide dispersion strengthened (ODS) steels by the addition of Y2O3 particles investigated in Part I were pre-damaged either with 20 MeV W ions at room temperature at IPP (Garching) or with high heat flux at FZJ (Juelich) and subsequently exposed to low energy (~20-200 eV per D) deuterium (D) plasma up to a fluence of 2.9  ×  1025 D m-2 in the temperature range from 290 K to 700 K. The pre-irradiation with 20 MeV W ions at room temperature up to 1 displacement per atom (dpa) has no noticeable influence on the steel surface morphology before and after the D plasma exposure. The pre-irradiation with W ions leads to the same concentration of deuterium in all kinds of investigated steels, regardless of the presence of nanoparticles and Cr content. It was found that (i) both kinds of irradiation with W ions and high heat flux increase the D retention in steels compared to undamaged steels and (ii) the D retention in both pre-damaged and undamaged steels decreases with a formation of surface roughness under the irradiation of steels with deuterium ions with incident energy which exceeds the threshold of sputtering. The increase in the D retention in RAFM steels pre-damaged either with W ions (damage up to ~3 µm) or high heat flux (damage up to ~10 µm) diminishes with increasing the temperature. It is important to mention that the near surface modifications caused by either implantation of high energy ions or a high heat flux load, significantly affect the total D retention at low temperatures or low fluences but have a negligible impact on the total D retention at elevated temperatures and high fluences because, in these cases, the D retention is mainly determined by bulk diffusion.

  19. The Cl + H2 --> HCl + H reaction induced by IR + UV irradiation of Cl2 in solid para-H2: quantum model simulation.

    PubMed

    Korolkov, M V; Manz, J; Schild, A

    2009-07-02

    Recent experimental investigations by the group of D. T. Anderson (Kettwich, S. C.; Raston, P. L.; Anderson, D. T. J. Phys. Chem. A 2009, 113, DOI 10.1021/jp811206a) show that the reaction Cl + H(2) --> HCl + H in the para-H(2) crystal can be induced by infrared (IR) + ultraviolet (UV) coirradiations causing vibrational pre-excitation of the molecular reactant, H(2)(v=1), and generation of the atomic reactant, Cl((2)P(3/2)), by near-resonant photodissociation of a matrix-isolated Cl(2) molecule in the C (1)Pi(u) state, respectively. The corresponding reaction probability P(v=1) for the reactants Cl + H(2)(v=1) is approximately 0.15; this is approximately 25 times larger than P(v=0) for Cl + H(2)(v=0) (as initiated by pure UV irradiation). We present a simple three-step quantum model which accounts for some important parts of the experimental results and allows predictions for other scenarios, for example, UV photodissociation of the Cl(2) molecule by a laser pulse. The first step, vibrational pre-excitation of H(2), yields the molecular initial state which is described using the Einstein model of the para-H(2) crystal. The second step, photodissociation of Cl(2), generates the Cl((2)P(3/2)) atom approaching H(2)(v=1). In the third step, Cl reacts with H(2)(v=1) much more efficiently than with H(2)(v=0) close to threshold. The ultrashort time domains (approximately 100 fs) of steps 2 plus 3 support one- and then two-dimensional models of photodissociation of Cl(2) by short laser pulses and of the subsequent reaction of the system Cl-H-H embedded in frozen environments. The widths of the corresponding wave function describing the translational motion of the reactants is revealed as a significant parameter which is determined not only by the duration of the laser pulse but, even more importantly, by the width of the Gaussian-type distribution of the center of mass of the H(2) molecule in its Einstein cell. As a consequence, the resulting P(v) are quite robust versus

  20. Quenched hydrogen-deuterium exchange NMR of a disease-relevant Aβ(1-42) amyloid polymorph

    PubMed Central

    Wälti, Marielle Aulikki; Orts, Julien; Riek, Roland

    2017-01-01

    Alzheimer’s disease is associated with the aggregation into amyloid fibrils of Aβ(1–42) and Aβ(1–40) peptides. Interestingly, these fibrils often do not obtain one single structure but rather show different morphologies, so-called polymorphs. Here, we compare quenched hydrogen-deuterium (H/D) exchange of a disease-relevant Aβ(1–42) fibril for which the 3D structure has been determined by solid-state NMR with H/D exchange previously determined on another structural polymorph. This comparison reveals secondary structural differences between the two polymorphs suggesting that the two polymorphisms can be classified as segmental polymorphs. PMID:28319116

  1. Single Crystal Growth and Formation of Defects in Deuterium-Tritium Ice Layers for Inertial Confinement Fusion

    SciTech Connect

    Chernov, A A; Kozioziemski, B J; Koch, J A; Atherton, L J; Johnson, M A; Hamza, A V; Kucheyev, S O; Lugten, J B; Mapoles, E A; Moody, J D; Salmonson, J D; Sater, J D

    2008-09-05

    We identify vapor-etched grain boundary grooves on the solid-vapor interface as the main source of surface roughness in the Deuterium-Tritium (D-T) fuel layers which are solidified and then cooled. Current inertial confinement fusion target designs impose stringent limits to the cross sectional area and total volume of these grooves. Formation of these grain boundaries occurs over timescales of hours as the dislocation network anneals, and is inevitable in a plastically deformed material. Therefore, either cooling on a much shorter time scale or a technique that requires no cooling after solidification should be used to minimize the fuel layer surface roughness.

  2. First Measurements of Deuterium-Tritium and Deuterium-Deuterium Fusion Reaction Yields in Ignition-Scalable Direct-Drive Implosions

    NASA Astrophysics Data System (ADS)

    Forrest, C. J.; Radha, P. B.; Knauer, J. P.; Glebov, V. Yu.; Goncharov, V. N.; Regan, S. P.; Rosenberg, M. J.; Sangster, T. C.; Shmayda, W. T.; Stoeckl, C.; Gatu Johnson, M.

    2017-03-01

    The deuterium-tritium (D-T) and deuterium-deuterium neutron yield ratio in cryogenic inertial confinement fusion (ICF) experiments is used to examine multifluid effects, traditionally not included in ICF modeling. This ratio has been measured for ignition-scalable direct-drive cryogenic DT implosions at the Omega Laser Facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997), 10.1016/S0030-4018(96)00325-2] using a high-dynamic-range neutron time-of-flight spectrometer. The experimentally inferred yield ratio is consistent with both the calculated values of the nuclear reaction rates and the measured preshot target-fuel composition. These observations indicate that the physical mechanisms that have been proposed to alter the fuel composition, such as species separation of the hydrogen isotopes [D. T. Casey et al., Phys. Rev. Lett. 108, 075002 (2012), 10.1103/PhysRevLett.108.075002], are not significant during the period of peak neutron production in ignition-scalable cryogenic direct-drive DT implosions.

  3. Paramagnetic Attraction of Impurity-Helium Solids

    NASA Technical Reports Server (NTRS)

    Bernard, E. P.; Boltnev, R. E.; Khmelenko, V. V.; Lee, D. M.

    2003-01-01

    Impurity-helium solids are formed when a mixture of impurity and helium gases enters a volume of superfluid helium. Typical choices of impurity gas are hydrogen deuteride, deuterium, nitrogen, neon and argon, or a mixture of these. These solids consist of individual impurity atoms and molecules as well as clusters of impurity atoms and molecules covered with layers of solidified helium. The clusters have an imperfect crystalline structure and diameters ranging up to 90 angstroms, depending somewhat on the choice of impurity. Immediately following formation the clusters aggregate into loosely connected porous solids that are submerged in and completely permeated by the liquid helium. Im-He solids are extremely effective at stabilizing high concentrations of free radicals, which can be introduced by applying a high power RF dis- charge to the impurity gas mixture just before it strikes the super fluid helium. Average concentrations of 10(exp 19) nitrogen atoms/cc and 5 x 10(exp 18) deuterium atoms/cc can be achieved this way. It shows a typical sample formed from a mixture of atomic and molecular hydrogen and deuterium. It shows typical sample formed from atomic and molecular nitrogen. Much of the stability of Im-He solids is attributed to their very large surface area to volume ratio and their permeation by super fluid helium. Heat resulting from a chance meeting and recombination of free radicals is quickly dissipated by the super fluid helium instead of thermally promoting the diffusion of other nearby free radicals.

  4. Deuterium retention in TiC and TaC doped tungsten at high temperatures

    NASA Astrophysics Data System (ADS)

    Zibrov, M.; Mayer, M.; Gao, L.; Elgeti, S.; Kurishita, H.; Gasparyan, Yu.; Pisarev, A.

    2015-08-01

    Samples made of tungsten doped either with titanium carbide (W-1.1TiC) or tantalum carbide (W-3.3TaC) were either exposed to D2 gas at a pressure of 100 kPa at 800-963 K or irradiated by 38 eV/D ions at 800 K. The deuterium (D) inventory in the samples was examined by nuclear reaction analysis and thermal desorption spectroscopy. The D bulk concentration and total retention in W-3.3TaC were comparable in all cases to that in pure polycrystalline W. The D bulk concentration in W-1.1TiC was more than one order of magnitude higher than that in pure W after exposure to D2 gas, and was also several times higher than that in W-1.1TiC after irradiation at 800 K. It is suggested that D trapping inside the carbide precipitates in W-1.1TiC becomes essential at high temperatures.

  5. Heterogeneous Catalysis: Deuterium Exchange Reactions of Hydrogen and Methane

    ERIC Educational Resources Information Center

    Mirich, Anne; Miller, Trisha Hoette; Klotz, Elsbeth; Mattson, Bruce

    2015-01-01

    Two gas phase deuterium/hydrogen exchange reactions are described utilizing a simple inexpensive glass catalyst tube containing 0.5% Pd on alumina through which gas mixtures can be passed and products collected for analysis. The first of these exchange reactions involves H[subscript 2] + D[subscript 2], which proceeds at temperatures as low as 77…

  6. Ordered ground states of metallic hydrogen and deuterium

    NASA Technical Reports Server (NTRS)

    Ashcroft, N. W.

    1981-01-01

    The physical attributes of some of the more physically distinct ordered states of metallic hydrogen and metallic deuterium at T = 0 and nearby are discussed. The likelihood of superconductivity in both is considered with respect to the usual coupling via the density fluctuations of the ions.

  7. Deuterium in interstitial water from deep-sea cores

    USGS Publications Warehouse

    Friedman, I.; Hardcastle, K.

    1988-01-01

    As part of the Joint Oceanographic Institutions Deep Earth Sampling project, the interstitial waters of cores from 69 holes were sampled for deuterium analysis to examine changes in the deuterium content of the oceans with time. Changes in the abundance of deuterium can be related to changes in the amount of ice stored in continental glaciers, inasmuch as precipitation in the form of snow is highly depleted in deuterium compared with the oceans. Many of the cores show a change in isotopic composition of samples from early to late Miocene that can be ascribed to the buildup of the Antarctic ice sheets. After correcting for the role of diffusion in reducing the isotopic contrast between samples from a single core, we estimate an incrase of 10 per mil (???) ??D (corresponding to a ??18O change of about 1.2???) between the early and late Miocene. A similar analysis of Pleistocene to Holocene changes indicates a ??D rise of 8??? during the time of maximum continental ice, which corresponds to a ??18O increase of about 1.0???. On the basis of limited data, we find no ??D change in the oceans from Cretaceous to Miocene. -from Authors

  8. URBAN STORMWATER TRACING WITH THE NATURALLY OCCURRING DEUTERIUM ISOTOPE

    EPA Science Inventory

    Measurements of the naturally-occurring deuterium isotope assist the tracing of water components during wet-weather flows in an urban watershed. A transect of installations in the vadose and saturated zones was completed in the vicinity of a small stream and storm sewer. High-r...

  9. Carbon Nanotube Based Deuterium Ion Source for Improved Neutron Generators

    SciTech Connect

    Fink, R. L.; Jiang, N.; Thuesen, L.; Leung, K. N.; Antolak, A. J.

    2009-03-10

    Field ionization uses high electric fields to cause the ionization and emission of ions from the surface of a sharp electrode. We are developing a novel field ionization neutron generator using carbon nanotubes (CNT) to produce the deuterium ion current. The generator consists of three major components: a deuterium ion source made of carbon nanotubes, a smooth negatively-biased target electrode, and a secondary electron suppression system. When a negative high voltage is applied on the target electrode, a high gradient electric field is formed at the tips of the carbon nanotubes. This field is sufficiently strong to create deuterium (D) ions at or near the nanotubes which are accelerated to the target causing D-D reactions to occur and the production of neutrons. A cross magnetic field is used to suppress secondary emission electrons generated on the target surface. We have demonstrated field ionization currents of 70 nA (1 {mu}A/cm{sup 2}) at hydrogen gas pressure of 10 mTorr. We have found that the current scales proportionally with CNT area and also with the gas pressure in the range of 1 mTorr to 10 mTorr. We have demonstrated pulse cut-off times as short as 2 {mu}sec. Finally, we have shown the feasibility of generating neutrons using deuterium gas.

  10. Laser separation of hydrogen isotopes: Tritium-from-deuterium recovery

    SciTech Connect

    Magnotta, F.; Herman, I.P.; Aldridge, F.T.; Maienschein, J.L.

    1984-02-01

    Single-step enrichment factors exceeding 15,000 have been observed in the removal of tritium-from-deuterium by 12 ..mu..m laser multiple-photon dissociation of chloroform. The photochemistry and photophysics of this process is discussed along with prospects for implementation of this method in practical heavy water reactor detritiation. 7 refs., 7 figs., 1 tab.

  11. Heterogeneous Catalysis: Deuterium Exchange Reactions of Hydrogen and Methane

    ERIC Educational Resources Information Center

    Mirich, Anne; Miller, Trisha Hoette; Klotz, Elsbeth; Mattson, Bruce

    2015-01-01

    Two gas phase deuterium/hydrogen exchange reactions are described utilizing a simple inexpensive glass catalyst tube containing 0.5% Pd on alumina through which gas mixtures can be passed and products collected for analysis. The first of these exchange reactions involves H[subscript 2] + D[subscript 2], which proceeds at temperatures as low as 77…

  12. 78 FR 79021 - Request for a License To Export; Deuterium

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... COMMISSION Request for a License To Export; Deuterium Pursuant to 10 CFR 110.70 (b) ``Public Notice of....gov/reading-rm.html at the NRC Homepage. A request for a hearing or petition for leave to intervene... Secretary, U.S. Department of State, Washington, DC 20520. A request for a hearing or petition for leave to...

  13. 78 FR 79018 - Request for a License To Export Deuterium

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... COMMISSION Request for a License To Export Deuterium Pursuant to 10 CFR 110.70 (b) ``Public Notice of Receipt....gov/reading-rm.html at the NRC Homepage. A request for a hearing or petition for leave to intervene... Secretary, U.S. Department of State, Washington, DC 20520. A request for a hearing or petition for leave to...

  14. Solid-phase synthesis of graphene quantum dots from the food additive citric acid under microwave irradiation and their use in live-cell imaging.

    PubMed

    Zhuang, Qianfen; Wang, Yong; Ni, Yongnian

    2016-05-01

    The work demonstrated that solid citric acid, one of the most common food additives, can be converted to graphene quantum dots (GQDs) under microwave heating. The as-prepared GQDs were further characterized by various analytical techniques like transmission electron microscopy, atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, fluorescence and UV-visible spectroscopy. Cytotoxicity of the GQDs was evaluated using HeLa cells. The result showed that the GQDs almost did not exhibit cytotoxicity at concentrations as high as 1000 µg mL(-1). In addition, it was found that the GQDs showed good solubility, excellent photostability, and excitation-dependent multicolor photoluminescence. Subsequently, the multicolor GQDs were successfully used as a fluorescence light-up probe for live-cell imaging. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Possibility of Solid-State Graft Copolymerization on Poly(ethylene terephthalate) Films by Plasma Irradiation and Effects of Surface Modification

    NASA Astrophysics Data System (ADS)

    Narushima, Kazuo; Matsuda, Noriko; Mizutani, Chie; Yamashita, Nanami; Inagaki, Norihiro; Iio, Kokoro; Isono, Yoshihiro; Islam, Mohammed Rafiqul

    2007-07-01

    A solid-state graft copolymerization for poly(ethylene terephthalate) (PET) films was proposed for a new surface modification technique. The functional groups included in graft monomers can be introduced on a PET surface. Allylbiguanide hydrochloric acid salt (ABG), N-methylol acrylamide (NM-AAm), and N-isopropyl acrylamide (NIP-AAm) were used as graft monomers. This technique led to a large change in the N/C atomic ratio on the PET film surfaces, which shows that nitrogen functional groups were introduced on PET surfaces. On the grafted PET films, a new N 1s spectrum appeared. This N 1s spectrum contained two components, namely, amino and amido groups, which suggests that the two groups were introduced onto the PET surfaces. In particular, isopropyl groups were introduced on the PET surface in the case of NIP-AAm. The formation of these functional groups demonstrated changes in the surface properties of PET, such as improved wettability.

  16. On the habitability of universes without stable deuterium

    NASA Astrophysics Data System (ADS)

    Adams, Fred C.; Grohs, Evan

    2017-05-01

    In both stars and in the early universe, the production of deuterium is the first step on the way to producing heavier nuclei. If the strong force were slightly weaker, then deuterium would not be stable, and many authors have noted that nuclesynthesis would be compromised so that helium production could not proceed through standard reaction chains. Motivated by the possibility that other regions of space-time could have different values for the fundamental constants, this paper considers stellar evolution in universes without stable deuterium and argues that such universes can remain habitable. Even in universes with no stellar nucleosynthesis, stars can form and will generate energy through gravitational contraction. Using both analytic estimates and a state-of-the-art stellar evolution code, we show that such stars can be sufficiently luminous and long-lived to support life. Stars with initial masses that exceed the Chandrasekhar mass cannot be supported by degeneracy pressure and will explode at the end of their contraction phase. The resulting explosive nucleosynthesis can thus provide the universe with some heavy elements. We also explore the possibility that helium can be produced in stellar cores through a triple-nucleon reaction that is roughly analogous to the triple-alpha reaction that operates in our universe. Stars burning hydrogen through this process are somewhat hotter than those in our universe, but otherwise play the same role. Next we show that with even trace amounts (metallicity Z ∼10-10) of heavy elements - produced through the triple-nucleon process or by explosive nucleosynthesis - the CNO cycle can operate and allow stars to function. Finally, we consider Big Bang Nucleosynthesis without stable deuterium and find that only trace amounts of helium are produced, with even smaller abundances of other nuclei. With stars evolving through gravitational contraction, explosive nucleosynthesis, the triple-nucleon reaction, and the CNO cycle

  17. Development of Approaches for Deuterium Incorporation in Plants

    SciTech Connect

    Evans, Barbara R

    2015-01-01

    Soon after the discovery of deuterium, efforts to utilize this stable isotope of hydrogen for labeling of plants began and have proven successful for natural abundance to 20% enrichment. However, isotopic labeling with deuterium (2H) in higher plants at the level of 40% and higher is complicated by both physiological responses, particularly water exchange through transpiration, and inhibitory effects of D2O on germination, rooting, and growth. The highest incorporation of 40 50% had been reported for photoheterotrophic cultivation of the duckweed Lemna. Higher substitution is desirable for certain applications using neutron scattering and nuclear magnetic resonance (NMR) techniques. 1H2H-NMR and mass spectroscopy are standard methods frequently used for determination of location and amount of deuterium substitution. The changes in infrared (IR) absorption observed for H to D substitution in hydroxyl and alkyl groups provide rapid initial evaluation of incorporation. Short-term experiments with cold-tolerant annual grasses can be carried out in enclosed growth containers to evaluate incorporation. Growth in individual chambers under continuous air perfusion with dried sterile-filtered air enables long-term cultivation of multiple plants at different D2O concentrations. Vegetative propagation from cuttings extends capabilities to species with low germination rates. Cultivation in 50% D2O of annual ryegrass and switchgrass following establishment of roots by growth in H2O produces samples with normal morphology and 30 40 % deuterium incorporation in the biomass. Winter grain rye (Secale cereale) was found to efficiently incorporate deuterium by photosynthetic fixation from 50% D2O but did not incorporate deuterated phenylalanine-d8 from the growth medium.

  18. Development of approaches for deuterium incorporation in plants.

    PubMed

    Evans, Barbara R; Shah, Riddhi

    2015-01-01

    Soon after the discovery of deuterium, efforts to utilize this stable isotope of hydrogen for labeling of plants began and have proven successful for natural abundance to 20% enrichment. However, isotopic labeling with deuterium ((2)H) in higher plants at the level of 40% and higher is complicated by both physiological responses, particularly water exchange through transpiration, and inhibitory effects of D2O on germination, rooting, and growth. The highest incorporation of 40-50% had been reported for photoheterotrophic cultivation of the duckweed Lemna. Higher substitution is desirable for certain applications using neutron scattering and nuclear magnetic resonance (NMR) techniques. (1)H(2)H NMR and mass spectroscopy are standard methods frequently used for determination of location and amount of deuterium substitution. The changes in infrared (IR) absorption observed for H to D substitution in hydroxyl and alkyl groups provide rapid initial evaluation of incorporation. Short-term experiments with cold-tolerant annual grasses can be carried out in enclosed growth containers to evaluate incorporation. Growth in individual chambers under continuous air perfusion with dried sterile-filtered air enables long-term cultivation of multiple plants at different D2O concentrations. Vegetative propagation from cuttings extends capabilities to species with low germination rates. Cultivation in 50% D2O of annual ryegrass and switchgrass following establishment of roots by growth in H2O produces samples with normal morphology and 30-40% deuterium incorporation in the biomass. Winter grain rye (Secale cereale) was found to efficiently incorporate deuterium by photosynthetic fixation from 50% D2O but did not incorporate deuterated phenylalanine-d8 from the growth medium. © 2015 Elsevier Inc. and UT-Battelle, LLC, Contract no. DE-AC05-00OR22725. All rights reserved.

  19. Effects of deuterium oxide on cell growth and vesicle speed in RBL-2H3 cells

    PubMed Central

    Triplett, Ashley R.

    2014-01-01

    For the first time we show the effects of deuterium oxide on cell growth and vesicle transport in rat basophilic leukemia (RBL-2H3) cells. RBL-2H3 cells cultured with 15 moles/L deuterium showed decreased cell growth which was attributed to cells not doubling their DNA content. Experimental observations also showed an increase in vesicle speed for cells cultured in deuterium oxide. This increase in vesicle speed was not observed in deuterium oxide cultures treated with a microtubule-destabilizing drug, suggesting that deuterium oxide affects microtubule-dependent vesicle transport. PMID:25237603

  20. Deuterium enrichment by selective photo-induced dissociation of an organic carbonyl compound

    DOEpatents

    Marling, John B.

    1981-01-01

    A method for producing a deuterium enriched material by photoinduced dissociation which uses as the working material a gas phase photolytically dissociable organic carbonyl compound containing at least one hydrogen atom bonded to an atom which is adjacent to a carbonyl group and consisting of molecules wherein said hydrogen atom is present as deuterium and molecules wherein said hydrogen atom is present as another isotope of hydrogen. The organic carbonyl compound is subjected to intense infrared radiation at a preselected wavelength to selectively excite and thereby induce dissociation of the deuterium containing species to yield a deuterium enriched stable molecular product. Undissociated carbonyl compound, depleted in deuterium, is preferably redeuterated for reuse.

  1. Localized Hydration in Lyophilized Myoglobin by Hydrogen-Deuterium Exchange Mass Spectrometry. 1. Exchange Mapping

    PubMed Central

    Sophocleous, Andreas M.; Zhang, Jun; Topp, Elizabeth M.

    2012-01-01

    The local effects of hydration on myoglobin (Mb) in solid matrices containing mannitol or sucrose (1:1 w/w, protein:additive) were mapped using hydrogen-deuterium exchange with mass spectrometric analysis (HDX-MS) at 5°C and compared to solution controls. Solid powders were exposed to D2O(g) at controlled activity (aw) followed by reconstitution and analysis of the intact protein and peptides produced by pepsin digestion. HDX varied with matrix type, aw, and position along the protein backbone. HDX was less in sucrose matrices than in mannitol matrices at all aw while the difference in solution was negligible. Differences in HDX in the two matrices were detectable despite similarities in their bulk water content. The extent of exchange in solids is proposed as a measure of the hydration of exchangeable amide groups, as well as protein conformation and dynamics; pepsin digestion allows these effects to be mapped with peptide-level resolution. PMID:22352965

  2. High-Dose Chemotherapy With or Without Total-Body Irradiation Followed by Autologous Stem Cell Transplant in Treating Patients With Hematologic Cancer or Solid Tumors

    ClinicalTrials.gov

    2017-03-30

    Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Malignant Testicular Germ Cell Tumor; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Neuroblastoma; Recurrent Small Lymphocytic Lymphoma; Recurrent/Refractory Childhood Hodgkin Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Multiple Myeloma; Regional Neuroblastoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Unspecified Adult Solid Tumor, Protocol Specific; Unspecified Childhood Solid Tumor, Protocol Specific; Waldenström Macroglobulinemia

  3. Tissue irradiator

    DOEpatents

    Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

    1975-12-16

    A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in- vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood- carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170.

  4. [Food irradiation].

    PubMed

    Migdał, W

    1995-01-01

    A worldwide standard on food irradiation was adopted in 1983 by Codex Alimentarius Commission of the Joint Food Standard Programme of the Food and Agriculture Organization (FAO) of the United Nations and the World Health Organization (WHO). As a result, 41 countries have approved the use of irradiation for treating one or more food items and the number is increasing. Generally, irradiation is used to: food loses, food spoilage, disinfestation, safety and hygiene. The number of countries which use irradiation for processing food for commercial purposes has been increasing steadily from 19 in 1987 to 33 today. In the frames of the national programme on the application of irradiation for food preservation and hygienization an experimental plant for electron beam processing has been established in Institute of Nuclear Chemistry and Technology. The plant is equipped with a small research accelerator Pilot (19MeV, 1 kW) and an industrial unit Elektronika (10MeV, 10 kW). On the basis of the research there were performed at different scientific institutions in Poland, health authorities have issued permission for irradiation for: spices, garlic, onions, mushrooms, potatoes, dry mushrooms and vegetables.

  5. Infrared Spectra of the 2-CHLOROETHYL Radical in Solid Para-Hydrogen

    NASA Astrophysics Data System (ADS)

    Amicangelo, Jay C.; Bahou, Mohammed; Golec, Barbara; Lee, Yuan-Pern

    2011-06-01

    The reaction of chlorine atoms with ethylene and two of its deuterium isotopomers in solid para-hydrogen (p-H2) matrices at 3 K has been studied using infrared spectroscopy. Irradiation at 365 nm of a co-deposited mixture of Cl2, C2H4, and p-H2 at 3 K produces a series of new lines in the infrared spectrum. Several of the new lines are readily assigned to the gauche and trans conformers of 1,2-dichloroethane (CH2ClCH2Cl) resulting from the addition of two Cl atoms to C2H4. Of the remaining lines, a strong line at 664 Cm-1 and three weaker lines at 562, 1070, and 1228 Cm-1 are concluded to be due to a single carrier based on their behavior upon subsequent annealing to 4.5 K and irradiation at 254 and 214 nm. When the positions and intensities of these lines are compared to the MP2/aug-cc-pVDZ predicted vibrational spectra of the possible species that could result from the addition and abstraction reactions of one Cl atom with C2H4, the best agreement is found with the 2-chloroethyl radical (CdotCH2CH2Cl). In order to confirm this assignment, isotopic experiments were performed with C2D4 and t-C2H2D2 and the corresponding infrared bands due to the deuterium isotopomers of this radical (CdotCD2CD2Cl and \\cdotCHDCHDCl) have been observed. A final set of experiments were performed following irradiation of the Cl2/C2H4/p-H2 mixture at 365 nm, in which the matrix was irradiated with filtered infrared light from a globar source, which has been shown to induce a reaction between isolated Cl atoms and matrix H2 to produce HCl and H atoms. In our experiments, the major products observed were HCl and ethyl chloride (CH3CH2Cl) and the possible mechanism of the formation of ethyl chloride will be discussed. P. Brana, B. Menendez, T. Fernandez, and J. A. Sordo, J. Phys. Chem. A 104, 10842 (2000) P. L. Raston and D. T. Anderson, Phys. Chem. Chem. Phys. 8, 3124 (2006)

  6. Separation of 44Ti from proton irradiated scandium by using solid-phase extraction chromatography and design of 44Ti/44Sc generator system

    SciTech Connect

    Radchenko, Valery; Meyer, Catherine Anne Louise; Engle, Jonathan Ward; Naranjo, Cleo Micah; Unc, George A.; Mastren, Tara; Brugh, Mark; Birnbaum, Eva R.; John, Kevin Dale; Nortier, Francois Meiring; Fassbender, Michael Ernst

    2016-11-24

    Scandium-44 g (half-life 3.97 h) shows promise for positron emission tomography (PET) imaging of longer biological processes than that of the current gold standard, 18F, due to its favorable decay parameters. One source of 44gSc is the long-lived parent nuclide 44Ti (half-life 60.0 a). A 44Ti/44gSc generator would have the ability to provide radionuclidically pure 44gSc on a daily basis. The production of 44Ti via the 45Sc(p,2n) reaction requires high proton beam currents and long irradiation times. Recovery and purification of no-carrier added (nca) 44Ti from scandium metal targets involves complex separation chemistry. In this study, separation systems based on solid phase extraction chromatography were investigated, including branched diglycolamide (BDGA) resin and hydroxamate based ZR resin. Lastly, results indicate that ZR resin in HCl media represents an effective 44Ti/44gSc separation system.

  7. Results from deuterium-tritium tokamak confinement experiments

    SciTech Connect

    Hawryluk, R.J.

    1997-02-01

    Recent scientific and technical progress in magnetic fusion experiments has resulted in the achievement of plasma parameters (density and temperature) which enabled the production of significant bursts of fusion power from deuterium-tritium fuels and the first studies of the physics of burning plasmas. The key scientific issues in the reacting plasma core are plasma confinement, magnetohydrodynamic (MHD) stability, and the confinement and loss of energetic fusion products from the reacting fuel ions. Progress in the development of regimes of operation which have both good confinement and are MHD stable have enabled a broad study of burning plasma physics issues. A review of the technical and scientific results from the deuterium-tritium experiments on the Joint European Torus (JET) and the Tokamak Fusion Test Reactor (TFTR) is given with particular emphasis on alpha-particle physics issues.

  8. Theory of the n = 2 levels in muonic deuterium

    NASA Astrophysics Data System (ADS)

    Krauth, Julian J.; Diepold, Marc; Franke, Beatrice; Antognini, Aldo; Kottmann, Franz; Pohl, Randolf

    2016-03-01

    The present knowledge of Lamb shift, fine- and hyperfine structure of the 2S and 2P states in muonic deuterium is reviewed in anticipation of the results of a first measurement of several 2S -2P transition frequencies in muonic deuterium (μd). A term-by-term comparison of all available sources reveals reliable values and uncertainties of the QED and nuclear structure-dependent contributions to the Lamb shift, which are essential for a determination of the deuteron rms charge radius from μd. Apparent discrepancies between different sources are resolved, in particular for the difficult two-photon exchange contributions. Problematic single-sourced terms are identified which require independent recalculation.

  9. Thermal X-rays and deuterium production in stellar flares

    NASA Technical Reports Server (NTRS)

    Colgate, S. A.

    1978-01-01

    The X-ray spectrum of flares is shown to be necessarily thermal up to at least 200 keV because the self-magnetic field of any electron stream required for a thick- or thin-target source is inconsistently large. The resulting flare model can then be related to stellar luminosity convection, and magnetic fields to result in a maximum possible gamma-burst and continuous X-ray flux. One of the most striking isotopic anomalies observed is the extreme enrichment of He-3 in some solar flares and the mysterious depletion of deuterium. The way in which deuterium may be produced and emitted in the largest flares associated with gamma-bursts but in amounts insufficient to support the tentative conclusion of Coleman and Worden (1976) is discussed.

  10. Techniques for determining total body water using deuterium oxide

    NASA Technical Reports Server (NTRS)

    Bishop, Phillip A.

    1990-01-01

    The measurement of total body water (TBW) is fundamental to the study of body fluid changes consequent to microgravity exposure or treatment with microgravity countermeasures. Often, the use of radioactive isotopes is prohibited for safety or other reasons. It was selected and implemented for use by some Johnson Space Center (JCS) laboratories, which permitted serial measurements over a 14 day period which was accurate enough to serve as a criterion method for validating new techniques. These requirements resulted in the selection of deuterium oxide dilution as the method of choice for TBW measurement. The development of this technique at JSC is reviewed. The recommended dosage, body fluid sampling techniques, and deuterium assay options are described.

  11. Detection of atomic deuterium in the upper atmosphere of Mars.

    PubMed

    Krasnopolsky, V A; Mumma, M J; Gladstone, G R

    1998-06-05

    High-resolution spectroscopy of Mars' atmosphere with the Hubble Space Telescope revealed the deuterium Lyman alpha line at an intensity of 23 +/- 6 rayleighs. This measured intensity corresponds to HD/H2 = 1.5 +/- 0.6 x 10(-4), which is smaller by a factor of 11 than HDO/H2O. This indicates that fractionation of HD/H2 relative to that of HDO/H2O is not kinetically controlled by the rates of formation and destruction of H2 and HD but is thermodynamically controlled by the isotope exchange HD + H2O left and right arrow HDO + H2. Molecular hydrogen is strongly depleted in deuterium relative to water on Mars because of the very long lifetime of H2 (1200 years). The derived isotope fractionation corresponds to an estimate of a planetwide reservoir of water ice about 5 meters thick that is exchangeable with the atmosphere.

  12. Laser-Driven Shock Compression Results on Deuterium

    NASA Astrophysics Data System (ADS)

    Hicks, D. G.; Celliers, P. M.; Collins, G. W.; Eggert, J. H.; Moon, S. J.; Foord, M. E.; Boehly, T. R.; Collins, T. J. B.; Vianello, E.; Jacobs-Perkins, D.; Meyerhofer, D. D.

    2003-10-01

    Laser-driven shock wave experiments have been performed at OMEGA to explore the equation of state of deuterium under double and single shock compression. We have developed a new technique of using a calibrated, high-pressure transparent material, quartz, which has enabled precision optical interferometer measurements of shock velocities. This approach significantly reduces the possibility of systematic error arising from shock unsteadiness. In the double-shock experiments, where quartz is used as a re-shock anvil, the results indicate deuterium has a compressibility that is close to the new SESAME and ab initio models below 1 Mbar but exhibits higher compressibility at larger pressures. In the single-shock, aluminum impedance-match experiments, quartz is used to accurately infer the shock velocity in aluminum; results from these recent experiments will be presented.

  13. On the abundance of deuterium in Jupiter's atmosphere

    NASA Technical Reports Server (NTRS)

    Combes, M.; Encrenaz, T.; Owen, T.

    1978-01-01

    The ratio of deuterium to hydrogen in the Jovian atmosphere has been calculated using a new approach. D/C is obtained from weak lines of HD and CH4 in the visible region of the spectrum while C/H is derived from stronger methane and hydrogen absorptions near 1 micron. This technique permits minimization of the varying effects on line formation caused by scattering in the Jovian atmosphere while relying on absorption bands whose strengths have been measured in the laboratory. The result is a deuterium-to-hydrogen ratio of 2.3 + or - 1.1 times 10 to the -5th power, within the range of local interstellar values

  14. The abundance of deuterium relative to hydrogen in interstellar space

    NASA Technical Reports Server (NTRS)

    York, D. G.; Rogerson, J. B., Jr.

    1976-01-01

    Copernicus satellite observations of the deuterium and hydrogen Lyman lines in the lines of sight to mu COl, gamma-2 Vel, alpha Cru AB, and alpha Vir AB are reported. Together with previously published data for beta Cen A, the results yield a value N(D)/N(H) of approximately 0.000018 (m.e.) or a total deuterium mass portion of approximately 0.000025. Values for all stars with their error bars are contained within a band ranging from 0.25 to 2.0 times the quoted mean ratio. These limits are probably representative of the region within 200 pc of the sun. The results for these stars are essentially independent of assumptions about the Doppler parameter describing the formation of the lines, although this value can be derived from the observations. The results are consistent with a maximum temperature of 6000 K for the lines of sight studied.

  15. On the identification of deuterium lines in QSO absorption systems

    NASA Astrophysics Data System (ADS)

    Levshakov, S. A.; Takahara, F.

    1996-07-01

    The ambiguity of identification of deuterium lines in QSO absorption systems is considered, under the assumption that the D I and H I absorption lines are formed in turbulent media with a finite correlation length of the stochastic velocity field. The relative shift of the D I and H I lines is shown to vary over the range +/-(4-8) km s^- 1^ for a cloud model with hydrogen column density N_HI_ = 10^17^ cm^-2^, the ratio D/H = 10^-4^, and kinetic temperature T_kin_ = 10^4^ K. The variations in the relative shift of the deuterium lines are fundamental in character and result from the stochastic nature of the formation of absorption lines in turbulent media

  16. The abundance of deuterium relative to hydrogen in interstellar space

    NASA Technical Reports Server (NTRS)

    York, D. G.; Rogerson, J. B., Jr.

    1976-01-01

    Copernicus satellite observations of the deuterium and hydrogen Lyman lines in the lines of sight to mu COl, gamma-2 Vel, alpha Cru AB, and alpha Vir AB are reported. Together with previously published data for beta Cen A, the results yield a value N(D)/N(H) of approximately 0.000018 (m.e.) or a total deuterium mass portion of approximately 0.000025. Values for all stars with their error bars are contained within a band ranging from 0.25 to 2.0 times the quoted mean ratio. These limits are probably representative of the region within 200 pc of the sun. The results for these stars are essentially independent of assumptions about the Doppler parameter describing the formation of the lines, although this value can be derived from the observations. The results are consistent with a maximum temperature of 6000 K for the lines of sight studied.

  17. Effects of Low-Level Deuterium Enrichment on Bacterial Growth

    PubMed Central

    Xie, Xueshu; Zubarev, Roman A.

    2014-01-01

    Using very precise (±0.05%) measurements of the growth parameters for bacteria E. coli grown on minimal media, we aimed to determine the lowest deuterium concentration at which the adverse effects that are prominent at higher enrichments start to become noticeable. Such a threshold was found at 0.5% D, a surprisingly high value, while the ultralow deuterium concentrations (≤0.25% D) showed signs of the opposite trend. Bacterial adaptation for 400 generations in isotopically different environment confirmed preference for ultralow (≤0.25% D) enrichment. This effect appears to be similar to those described in sporadic but multiple earlier reports. Possible explanations include hormesis and isotopic resonance phenomena, with the latter explanation being favored. PMID:25033078

  18. Effects of low-level deuterium enrichment on bacterial growth.

    PubMed

    Xie, Xueshu; Zubarev, Roman A

    2014-01-01

    Using very precise (±0.05%) measurements of the growth parameters for bacteria E. coli grown on minimal media, we aimed to determine the lowest deuterium concentration at which the adverse effects that are prominent at higher enrichments start to become noticeable. Such a threshold was found at 0.5% D, a surprisingly high value, while the ultralow deuterium concentrations (≤0.25% D) showed signs of the opposite trend. Bacterial adaptation for 400 generations in isotopically different environment confirmed preference for ultralow (≤0.25% D) enrichment. This effect appears to be similar to those described in sporadic but multiple earlier reports. Possible explanations include hormesis and isotopic resonance phenomena, with the latter explanation being favored.

  19. On the abundance of deuterium in Jupiter's atmosphere

    NASA Technical Reports Server (NTRS)

    Combes, M.; Encrenaz, T.; Owen, T.

    1978-01-01

    The ratio of deuterium to hydrogen in the Jovian atmosphere has been calculated using a new approach. D/C is obtained from weak lines of HD and CH4 in the visible region of the spectrum while C/H is derived from stronger methane and hydrogen absorptions near 1 micron. This technique permits minimization of the varying effects on line formation caused by scattering in the Jovian atmosphere while relying on absorption bands whose strengths have been measured in the laboratory. The result is a deuterium-to-hydrogen ratio of 2.3 + or - 1.1 times 10 to the -5th power, within the range of local interstellar values

  20. Detection of atomic deuterium in the upper atmosphere of Mars

    NASA Technical Reports Server (NTRS)

    Krasnopolsky, V. A.; Mumma, M. J.; Gladstone, G. R.

    1998-01-01

    High-resolution spectroscopy of Mars' atmosphere with the Hubble Space Telescope revealed the deuterium Lyman alpha line at an intensity of 23 +/- 6 rayleighs. This measured intensity corresponds to HD/H2 = 1.5 +/- 0.6 x 10(-4), which is smaller by a factor of 11 than HDO/H2O. This indicates that fractionation of HD/H2 relative to that of HDO/H2O is not kinetically controlled by the rates of formation and destruction of H2 and HD but is thermodynamically controlled by the isotope exchange HD + H2O left and right arrow HDO + H2. Molecular hydrogen is strongly depleted in deuterium relative to water on Mars because of the very long lifetime of H2 (1200 years). The derived isotope fractionation corresponds to an estimate of a planetwide reservoir of water ice about 5 meters thick that is exchangeable with the atmosphere.