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Sample records for pellet injection experiments

  1. Impurity pellet injection experiments at TFTR

    SciTech Connect

    Marmar, E.S.

    1992-01-01

    Impurity (Li and C) pellet injection experiments on TFTR have produced a number of new and significant results. (1) We observe reproducible improvements of TFTR supershots after wall-conditioning by Li pellet injection ( lithiumization'). (2) We have made accurate measurements of the pitch angle profiles of the internal magnetic field using two novel techniques. The first measures the internal field pitch from the polarization angles of Li[sup +] line emission from the pellet ablation cloud, while the second measures the pitch angle profiles by observing the tilt of the cigar-shaped Li[sup +] emission region of the ablation cloud. (3) Extensive measurements of impurity pellet penetration into plasmas with central temperatures ranging from [approximately]0.3 to [approximately]7 keV have been made and compared with available theoretical models. Other aspects of pellet cloud physics have been investigated. (4) Using pellets as a well defined perturbation has allowed study of transport phenomena. In the case of small pellet perturbations, the characteristics of the background plasmas are probed, while with large pellets, pellet induced effects are clearly observed. These main results are discussed in more detail in this paper.

  2. Impurity pellet injection experiments at TFTR. Final performance report

    SciTech Connect

    Marmar, E.S.

    1992-12-01

    Impurity (Li and C) pellet injection experiments on TFTR have produced a number of new and significant results. (1) We observe reproducible improvements of TFTR supershots after wall-conditioning by Li pellet injection (`lithiumization`). (2) We have made accurate measurements of the pitch angle profiles of the internal magnetic field using two novel techniques. The first measures the internal field pitch from the polarization angles of Li{sup +} line emission from the pellet ablation cloud, while the second measures the pitch angle profiles by observing the tilt of the cigar-shaped Li{sup +} emission region of the ablation cloud. (3) Extensive measurements of impurity pellet penetration into plasmas with central temperatures ranging from {approximately}0.3 to {approximately}7 keV have been made and compared with available theoretical models. Other aspects of pellet cloud physics have been investigated. (4) Using pellets as a well defined perturbation has allowed study of transport phenomena. In the case of small pellet perturbations, the characteristics of the background plasmas are probed, while with large pellets, pellet induced effects are clearly observed. These main results are discussed in more detail in this paper.

  3. Particle balance studies in TEXTOR during experiments of pellet injection, helium injection, and ICR-heating

    NASA Astrophysics Data System (ADS)

    Banno, T.; Noda, N.; Finken, K. H.; Gray, D. S.; Winter, J.; Alt-Ii Team; Textor Team

    1995-04-01

    Analysis based on the particle conservation law has been carried out to observe the global fuelling process in tokamak discharges. The response of the net recycling flux from the first wall is investigated in the tokamak TEXTOR, using calibrated signals of the gas feed rate, the neutral gas pressure in the vessel, the total amount of electrons, and the particle removal rates by the ALT-II belt-pump limiter and by a main pump unit. Net absorption (pumping) of hydrogen by the wall is observed for almost all tokamak discharges since a new wall conditioning technique called siliconisation is employed. The net absorption or fuelling depending on the discharge condition influenced by injection of pellets, by helium gas injection combined with neutral beam injection, and by rf heating can be interpreted in terms of the particle-induced desorption effect with depth profile taken into consideration.

  4. Analysis of D pellet injection experiments in the W7-AS Stellarator

    SciTech Connect

    Lyon, J.F.; Baylor, L.R.; Baldzuhn, J.; Fiedler, S.; Hirsch, M.; Kuehner, G.; Weller, A.

    1997-07-01

    A centrifugal injector was used to inject deuterium pellets (with 3--5 x 10{sup 19} atoms) at approx. equal 600 m/s into current-less, nearly shear-less plasmas in the Wendelstein 7-AS (W7-AS) stellarator. The D pellet was injected horizontally at a location where the non-circular and non-axisymmetric plasma cross section is nearly triangular. Visible-light TV pictures usually showed the pellet as a single ablating mass in the plasma, although the pellet occasionally broke in two or splintered into a cloud of small particles. The density evolution following pellet injection and the effect of pellet injection on energy confinement and fluctuations are discussed.

  5. Lithium pellet injection experiments on the Alcator C-Mod tokamak

    SciTech Connect

    Garnier, Darren Thomas

    1996-06-01

    A pellet enhanced performance mode, showing significantly reduced core transport, is regularly obtained after the injection of deeply penetrating lithium pellets into Alcator C-Mod discharges. These transient modes, which typically persist about two energy confinement times, are characterized by a steep pressure gradient (ℓp ℓ a/5) in the inner third of the plasma, indicating the presence of an internal transport barrier. Inside this barrier, particle and energy diffusivities are greatly reduced, with ion thermal diffusivity dropping to near neoclassical values. Meanwhile, the global energy confinement time shows a 30% improvement over ITER89-P L-mode scaling. The addition of ICRF auxiliary heating shortly after the pellet injection leads to high fusion reactivity with neutron rates enhanced by an order of magnitude over L-mode discharges with similar input powers. A diagnostic system for measuring equilibrium current density profiles of tokamak plasmas, employing high speed lithium pellets, is also presented. Because ions are confined to move along field lines, imaging the Li+ emission from the toroidally extended pellet ablation cloud gives the direction of the magnetic field. To convert from temporal to radial measurements, the 3-D trajectory of the pellet is determined using a stereoscopic tracking system. These measurements, along with external magnetic measurements, are used to solve the Grad-Shafranov equation for the magnetic equilibrium of the plasma. This diagnostic is used to determine the current density profile of PEP modes by injection of a second pellet during the period of good confinement. This measurement indicates that a region of reversed magnetic shear exists at the plasma core. This current density profile is consistent with TRANSP calculations for the bootstrap current created by the pressure gradient. MHD stability analysis indicates that these plasmas are near the n = ∞ and the n = 1 marginal stability limits.

  6. Initial NSTX Lithium Pellet Injection

    NASA Astrophysics Data System (ADS)

    Kugel, H. W.; Bell, M.; Bell, R.; Biewer, T.; Gates, D.; Jardin, S.; Kaita, R.; Leblanc, B.; Paul, S.; Samtaney, R.; Skinner, C. H.; Raman, R.; Bush, C.; Maingi, R.; Soukhanovskii, V.; Nishino, N.; Lee, K. C.; Stutman, D.

    2004-11-01

    A cartridge style Lithium Pellet Injector was installed on NSTX for midplane radial injection. Deuterium gas was used to propel a Li pellet-bearing cartridge down a barrel to a cartridge stop, and the pellet continued into the NSTX plasma at about 150 m/s. 16 lithium pellets, about 2 mg each were injected into LSN and DND, NBI-heated, H-mode plasmas, and into L-mode LSN Ohmic plasmas, and were observed with a Li I filtered Plasma-TV. Li pellets injected into NBI-heated LSN and DND plasmas appeared to ablate in the outer boundary. The pellets injected into OH plasmas exhibited good penetration to the HFS region. Lastly, a NBI preheat was added prior to pellet arrival, and the penetration depth was found to be very sensitive to the NBI turn-off time relative to pellet arrival. As this work progressed, Li luminosity started to be observed from the very initiation of discharges, due to depositions from preceding discharges. Initial modeling results will be presented.

  7. Pellet injection into ATF plasmas

    SciTech Connect

    Wilgen, J.B.; Bell, J.D.; England, A.C.; Fisher, P.W.; Howe, H.C.; Murakami, M.; Rasmussen, D.A.; Richards, R.K.; Uckan, T.; Wing, W.R. ); Bell, G.L. ); Qualls, A.L. ); Sudo, S. )

    1990-01-01

    Based on the favorable empirical scaling of stellarator confinement with increasing electron density, pellet fueling is expected to result in significant performance improvement of the ATF plasma. With gas-puff fueling, NBI heated plasmas in ATF are limited by a thermal collapse. Pellet fueling provides a potential means to delay this effect and gain access to the favorable high density confinement regime. To provide flexibility for optimization and physics studies, eight different pellet sizes are available. To date, line average densities of up to 4 {times} 10{sup 13} cm{sup {minus}3} have been achieved with a single pellet injected into a 0.7 MW NBI plasma at 0.95 T; the results from optimization studies with up to 1.5 MW of NBI power at 2 T will be presented.

  8. Model for pneumatic pellet injection

    SciTech Connect

    Hogan, J.T.; Milora, S.L.; Schuresko, D.D.

    1983-07-01

    A hydrodynamic code has been developed to model the performance of pneumatic pellet injection systems. The code describes one dimensional, unsteady compressible gas dynamics, including gas friction and heat transfer to the walls in a system with variable area. The mass, momentum, and energy equations are solved with an iterated Lax-Wendroff scheme with additional numerical viscosity. The code is described and comparisons with experimental data are presented.

  9. Tritium pellet injection sequences for TFTR

    SciTech Connect

    Houlberg, W.A.; Milora, S.L.; Attenberger, S.E.; Singer, C.E.; Schmidt, G.L.

    1983-01-01

    Tritium pellet injection into neutral deuterium, beam heated deuterium plasmas in the Tokamak Fusion Test Reactor (TFTR) is shown to be an attractive means of (1) minimizing tritium use per tritium discharge and over a sequence of tritium discharges; (2) greatly reducing the tritium load in the walls, limiters, getters, and cryopanels; (3) maintaining or improving instantaneous neutron production (Q); (4) reducing or eliminating deuterium-tritium (D-T) neutron production in non-optimized discharges; and (5) generally adding flexibility to the experimental sequences leading to optimal Q operation. Transport analyses of both compression and full-bore TFTR plasmas are used to support the above observations and to provide the basis for a proposed eight-pellet gas gun injector for the 1986 tritium experiments.

  10. Pellet injector development and experiments at ORNL

    SciTech Connect

    Baylor, L.R.; Argo, B.E.; Barber, G.C.; Combs, S.K.; Cole, M.J.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Gouge, M.J.; Jernigan, T.C.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Schechter, D.E.; Sparks, D.O.; Tsai, C.C.; Wilgen, J.B.; Whealton, J.H.

    1993-11-01

    The development of pellet injectors for plasma fueling of magnetic confinement fusion experiments has been under way at Oak Ridge National Laboratory (ORNL) for the past 15 years. Recently, ORNL provided a tritium-compatible four-shot pneumatic injector for the Tokamak Fusion Test Reactor (TFTR) based on the in situ condensation technique that features three single-stage gas guns and an advanced two-stage light gas gun driver. In another application, ORNL supplied the Tore Supra tokamak with a centrifuge pellet injector in 1989 for pellet fueling experiments that has achieved record numbers of injected pellets into a discharge. Work is progressing on an upgrade to that injector to extend the number of pellets to 400 and improve pellet repeatability. In a new application, the ORNL three barrel repeating pneumatic injector has been returned from JET and is being readied for installation on the DIII-D device for fueling and enhanced plasma performance experiments. In addition to these experimental applications, ORNL is developing advanced injector technologies, including high-velocity pellet injectors, tritium pellet injectors, and long-pulse feed systems. The two-stage light gas gun and electron-beam-driven rocket are the acceleration techniques under investigation for achieving high velocity. A tritium proof-of-principle (TPOP) experiment has demonstrated the feasibility of tritium pellet production and acceleration. A new tritium-compatible, extruder-based, repeating pneumatic injector is being fabricated to replace the pipe gun in the TPOP experiment and will explore issues related to the extrudability of tritium and acceleration of large tritium pellets. The tritium pellet formation experiments and development of long-pulse pellet feed systems are especially relevant to the International Tokamak Engineering Reactor (ITER).

  11. Current generation by phased injection of pellets

    SciTech Connect

    Fisch, N.J.

    1983-08-01

    By phasing the injection of frozen pellets into a tokamak plasma, it is possible to generate current. The current occurs when the electron flux to individual members of an array of pellets is asymmetric with respect to the magnetic field. The utility of this method for tokamak reactors, however, is unclear; the current, even though free in a pellet-fueled reactor, may not be large enough to be worth the trouble. Uncertainty as to the utility of this method is, in part, due to uncertainty as to proper modeling of the one-pellet problem.

  12. Fueling efficiency of pellet injection on DIII-D

    SciTech Connect

    Baylor, L.R.; Jernigan, T.C.; Maingi, R.; Lasnier, C.J.; Ali Mahdavi, M.

    1998-05-01

    Pellet injection has been used on the DIII-D tokamak to study density limits and particle transport in H-mode and inner wall limited L-mode plasmas. These experiments have provided a variety of conditions in which to examine the fueling efficiency of pellets injected into DIII-D plasmas. The fueling efficiency defined as the total increase in number of plasma electrons divided by the number of pellet fuel atoms, is determined by measurements of density profiles before and just after pellet injection. The authors have found that there is a decrease in the pellet fueling efficiency with increased neutral beam injection power. The pellet penetration depth also decreases with increased neutral beam injection power so that, in general, fueling efficiency increases with penetration depth. The fueling efficiency is generally 25% lower in ELMing H-mode discharges than in L-mode due to an expulsion of particles with a pellet triggered ELM. A comparison with fueling efficiency data from other tokamaks shows similar behavior.

  13. A Comparison of Fueling with Deuterium Pellet Injection from Different Locations on the DIII-D Tokamak

    SciTech Connect

    Baylor, L.R.; Combs, S.K.; Gohil, P.; Houlberg, W.A.; Hsieh, C.; Jernigan, T.C.; Parks, P.B.

    1999-06-14

    Initial pellet injection experiments on DIII-D with high field side (HFS) injection have demonstrated that deeper pellet fuel deposition is possible even with HFS injected pellets that are significantly slower than pellets injected from the low field side (LFS) (outer midplane) location. A radial displacement of the pellet mass shortly after or during the ablation process is consistent with the observed mass deposition profiles measured shortly after injection. Vertical injection inside the magnetic axis shows some improvement in fueling efficiency over LFS injection and may provide an optimal injection location for fueling with high speed pellets.

  14. A Compact Flexible Pellet Injection System for Fueling Studies

    NASA Astrophysics Data System (ADS)

    Baylor, L. R.; Combs, S. K.; Fehling, D. T.; Fisher, P. W.; Foust, C. R.; Gouge, M. J.; Rasmussen, D. A.

    2000-10-01

    A compact pellet injection system is being designed and built at ORNL to provide a flexible pellet fueling system for studies in magnetic confinement fusion devices. The system known as a ``pellet injector in a suitcase (PIS)'' is a pipe gun device with four barrels that uses a cryocooler for in-situ hydrogenic pellet formation. The system is being built to provide a flexible, low-cost fueling system that can be used on a number of plasma confinement experiments with minimal installation and operation costs. components in the system. It will use both propellant gas and a mechanical punch to accelerate the 1 - 4 mm size pellets to 100-1500 m/s. With the mechanical punch alone a low speed pellet, useful for curved guide tube applications, can be produced with minimal gas load eliminating the need for a large ballast volume. can be independently fired. diagnose the injector. The PIS is a flexible tool for fueling alternative concept devices such as MST and NSTX and for specialized studies in mainline tokamak experiments such as DIII-D and JET. The small size makes installation on such devices more feasible. of the system design and the expected performance will be presented.

  15. Results of hydrogen pellet injection into ISX-B

    SciTech Connect

    Milora, S.L.; Foster, C.A.; Thomas, C.E.

    1980-09-01

    High speed pellet fueling experiments have been performed on the ISX-B device in a new regime characterized by large global density rise in both ohmic and neutral beam heated discharges. Hydrogen pellets of 1 mm in diameter were injected in the plasma midplane at velocities exceeding 1 km/s. In low temperature ohmic discharges, pellets penetrate beyond the magnetic axis, and in such cases a sharp decrease in ablation is observed as the pellet passes the plasma center. Density increases of approx. 300% have been observed without degrading plasma stability or confinement. Energy confinement time increases in agreement with the empirical scaling tau/sub E/ approx. n/sub e/ and central ion temperature increases as a result of improved ion-electron coupling. Laser-Thomson scattering and radiometer measurements indicate that the pellet interaction with the plasma is adiabatic. Penetration to r/a approx. 0.15 is optimal, in which case large amplitude sawtooth oscillations are observed and the density remains elevated. Gross plasma stability is dependent roughly on the amount of pellet penetration and can be correlated with the expected temporal evolution of the current density profile.

  16. Development of a Tritium Extruder for ITER Pellet Injection

    SciTech Connect

    M.J. Gouge; P.W. Fisher

    1998-09-01

    As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first-wall tritium inventories by a process of "isotopic fueling" in which tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge. This repeating single-stage pneumatic pellet injector, called the Tritium-Proof-of-Principle Phase II (TPOP-II) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude and accelerate hydrogenic pellets sized for the ITER device. The TPOP-II program has the following development goals: evaluate the feasibility of extruding tritium and deuterium-tritium (D-T) mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and D-T extrusions; integrate, test, and evaluate the extruder in a repeating, single-stage light gas gun that is sized for the ITER application (pellet diameter -7 to 8 mm); evaluate options for recycling propellant and extruder exhaust gas; and evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory that requires secondary and room containment systems. In tests with deuterium feed at ORNL, up to 13 pellets per extrusion have been extruded at rates up to 1 Hz and accelerated to speeds of 1.0 to 1.1 km/s, using hydrogen propellant gas at a supply pressure of 65 bar. Initially, deuterium pellets 7.5 mm in diameter and 11 mm in length were produced-the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 10% density perturbation to ITER. Subsequently, the extruder nozzle was modified to produce pellets that are almost 7.5-mm right circular

  17. New Pellet Injection Schemes on DIII-D

    SciTech Connect

    Anderson, P.M.; Baylor, L.R.; Combs, S.K.; Foust, C.R.; Jernigan, T.C.; Robinson, J.I.

    1999-11-13

    The pellet fueling system on DIII-D has been modified for injection of deuterium pellets from two vertical ports and two inner wall locations on the magnetic high-field side (HFS) of the tokamak. The HFS pellet injection technique was first employed on ASDEX-Upgrade with significant improvements reported in both pellet penetration and fueling efficiency. The new pellet injection schemes on DIII-D required the installation of new guide tubes. These lines are {approx_equal}12.5 m in total length and are made up of complex bends and turns (''roller coaster'' like) to route pellets from the injector to the plasma, including sections inside the torus. The pellet speed at which intact pellets can survive through the curved guide tubes is limited ({approx_equal}200-300 m/s for HFS injection schemes). Thus, one of the three gas guns on the injector was modified to provide pellets in a lower speed regime than the original guns (normal speed range {approx_equal}500 to 1000 m/s). The guide tube installations and gun modifications are described along with the injector operating parameters, and the latest test results are highlighted.

  18. A new centrifuge pellet injector for fusion experiments

    NASA Astrophysics Data System (ADS)

    Andelfinger, C.; Buchelt, E.; Cierpka, P.; Kollotzek, H.; Lang, P. T.; Lang, R. S.; Prausner, G.; Söldner, F. X.; Ulrich, M.; Weber, G.

    1993-04-01

    This paper reports on the new pellet injection system for refueling the ASDEX Upgrade tokamak with cubic H2 or D2 pellets having alternative side lengths of 1.5, 1.75, and 2.0 mm and optional Ne doping. The system delivers series of about 100 pellets at a maximum repetition rate of more than 40 Hz. The pellets are accelerated by means of a centrifuge with an optimized straight acceleration arm. This configuration minimizes the compulsive force acting on the pellet during the acceleration process. Since this also minimizes stresses inside the pellet, high velocities—a maximum of 1211 m/s being achieved—are possible without destroying the hydrogen cubes. A special pellet feed-in technique based on a static stop cylinder interrupting the acceleration path successfully reduced the horizontal scattering angle to values of less than ±4°; a high efficiency, with more than 90% of the pellets arriving within the acceptance angle, was thus achieved. The whole system was found to work very reliably and reproducibly during the whole test operation period, covering about 105 pellet shots, and is now being integrated into the ASDEX upgrade experiment.

  19. Achieving temporary divertor plasma detachment with MARFE events by pellet injection in the EAST superconducting tokamak

    NASA Astrophysics Data System (ADS)

    Guozhong, Deng; Liang, Wang; Xiaoju, Liu; Yanmin, Duan; Jiansheng, Hu; Changzheng, Li; Ling, Zhang; Shaocheng, Liu; Huiqian, Wang; Liang, Chen; Jichan, Xu; Wei, Feng; Jianbin, Liu; Huan, Liu; Guosheng, Xu; Houyang, Guo; Xiang, Gao; the EAST Team

    2017-01-01

    A new pellet injection system has been equipped on the experimental advanced superconducting tokamak (EAST) in the 2012 campaign, with a pellet size of ϕ 2 mm × 2 mm, a frequency of 1 Hz-10 Hz and velocity of 150 m s-1-300 m s-1. The deuterium pellet is well-known for plasma fuelling as well as for triggering the edge localized mode (ELM). In the 2012 campaign, pellet injection experiments were successfully carried out on EAST. Temporary plasma detachment achieved by deuterium pellets has been observed in a double null (DN) divertor configuration, with multi-pellet injections at a repetition frequency of 2 Hz. The partial detachment of the outer divertors and complete detachment of the inner divertors was achieved after 35 ms of each pellet injection, which have a duration of 30-60 ms with the maximum degree of detachment (DOD) reaching 3.5 and 37, respectively. Meanwhile, the multifaceted asymmetric radiation from the edge (MARFE) phenomena was also observed at the high field side (HFS) near both the lower and upper X-points with radiation loss suddenly increased to about 15%-70%, which may be the main cause of divertor plasma detachment. The temporary detachment induced by pellet injection may act as a new way to study divertor detachment behaviors.

  20. Lithium wall conditioning by high frequency pellet injection in RFX-mod

    NASA Astrophysics Data System (ADS)

    Innocente, P.; Mansfield, D. K.; Roquemore, A. L.; Agostini, M.; Barison, S.; Canton, A.; Carraro, L.; Cavazzana, R.; De Masi, G.; Fassina, A.; Fiameni, S.; Grando, L.; Rais, B.; Rossetto, F.; Scarin, P.

    2015-08-01

    In the RFX-mod reversed field pinch experiment, lithium wall conditioning has been tested with multiple scopes: to improve density control, to reduce impurities and to increase energy and particle confinement time. Large single lithium pellet injection, lithium capillary-pore system and lithium evaporation has been used for lithiumization. The last two methods, which presently provide the best results in tokamak devices, have limited applicability in the RFX-mod device due to the magnetic field characteristics and geometrical constraints. On the other side, the first mentioned technique did not allow injecting large amount of lithium. To improve the deposition, recently in RFX-mod small lithium multi-pellets injection has been tested. In this paper we compare lithium multi-pellets injection to the other techniques. Multi-pellets gave more uniform Li deposition than evaporator, but provided similar effects on plasma parameters, showing that further optimizations are required.

  1. Potential safe termination by injection of polypropylene pellets in JET

    SciTech Connect

    Schmidt, G.L.; Ali-Arshad, S.; Bartlett, D.

    1995-10-01

    Thermal energy and the magnetic field energy associated with the plasma current must be dissipated safely when a tokamak discharge is terminated in a disruption. Magnetic energy can be dissipated by impurity radiation if position control is maintained. Prior to the dissipation of magnetic energy, thermal energy is usually conducted to the plasma contact points on a 1ms time scale in a thermal quench. A resistive, highly radiating plasma formed prior to the thermal quench, might dissipate both the thermal and magnetic energy by radiation minimizing damage due to local deposition. High speed injection of a low Z material can produce a resistive, highly radiating plasma on a 1ms time scale. Neon has recently been used in such an application on JT60-U. A large carbon pellet producing dilution temperatures < 1 keV is a possible alternative. This paper summarizes the results of an initial experiment performed in JET using carbon injected at high speed, as a 6mm polypropylene pellet, to investigate this potential approach to a safe plasma termination.

  2. Overview of Recent Developments in Pellet Injection for ITER

    SciTech Connect

    Combs, Stephen Kirk; Baylor, Larry R; Meitner, Steven J; Caughman, John B; Rasmussen, David A; Maruyama, So

    2012-01-01

    Pellet injection is the primary fueling technique planned for core fueling of ITER burning plasmas. Also, the injection of relatively small pellets to purposely trigger rapid small edge localized modes (ELMs) has been proposed as a possible solution to the heat flux damage from larger natural ELMs likely to be an issue on the ITER divertor surfaces. The ITER pellet injection system is designed to inject pellets into the plasma through both inner and outer wall guide tubes. The inner wall guide tubes will provide high throughput pellet fueling while the outerwall guide tubes will be used primarily to trigger ELMs at a high frequency (>15 Hz). The pellet fueling rate ofeach injector is to be up to 120 Pa-m3/s, which will require the formation of solid D-T at a volumetric rate of ~1500 mm3/s. Two injectors are to be provided for ITER at the startup with a provision for up to six injectorsduring the D-T phase. The required throughput of each injector is greater than that of any injector built to date, and a novel twin-screw continuous extrusion system is being developed to meet the challenging design parameters. Status of the development activities will be presented, highlighting recent progress.

  3. Plasma gun pellet acceleration modeling and experiment

    SciTech Connect

    Kincaid, R.W.; Bourham, M.A.; Gilligan, J.G.

    1996-12-31

    Modifications to the electrothermal plasma gun SIRENS have been completed to allow for acceleration experiments using plastic pellets. Modifications have been implemented to the 1-D, time dependent code ODIN to include pellet friction, momentum, and kinetic energy with options of variable barrel length. The code results in the new version, POSEIDON, compare favorably with experimental data and with code results from ODIN. Predicted values show an increased pellet velocity along the barrel length, achieving 2 km/s exit velocity. Measured velocity, at three locations along the barrel length, showed good correlation with predicted values. The code has also been used to investigate the effectiveness of longer pulse length on pellet velocity using simulated ramp up and down currents with flat top, and triangular current pulses with early and late peaking. 16 refs., 5 figs.

  4. Tracer-Encapsulated Solid Pellet (TESPEL) Injection System for the TJ-II Stellarator

    SciTech Connect

    Tamura, N.; McCarthy, K. J.; Hayashi, H.; Combs, Stephen Kirk; Foust, Charles R; Garcia, R.; Panadero, N.; Pawelec, E.; Sanchez, J. Hernandez; Navarro, M.; Soleto, A.

    2016-01-01

    A tracer-encapsulated solid pellet (TESPEL) injection system for the TJ-II stellarator was recently developed. In order to reduce the time and cost for the development, we combined a TESPEL injector provided by National Institute for Fusion Science with an existing TJ-II cryogenic pellet injection system. Consequently, the TESPEL injection into the TJ-II plasma was successfully achieved, which was confirmed by several pellet diagnostics including a normal-incidence spectrometer for monitoring a tracer impurity behavior.

  5. Tracer-Encapsulated Solid Pellet (TESPEL) injection system for the TJ-II stellarator

    NASA Astrophysics Data System (ADS)

    Tamura, N.; McCarthy, K. J.; Hayashi, H.; Combs, S. K.; Foust, C.; García, R.; Panadero, N.; Pawelec, E.; Hernández Sánchez, J.; Navarro, M.; Soleto, A.

    2016-11-01

    A tracer-encapsulated solid pellet (TESPEL) injection system for the TJ-II stellarator was recently developed. In order to reduce the time and cost for the development, we combined a TESPEL injector provided by National Institute for Fusion Science with an existing TJ-II cryogenic pellet injection system. Consequently, the TESPEL injection into the TJ-II plasma was successfully achieved, which was confirmed by several pellet diagnostics including a normal-incidence spectrometer for monitoring a tracer impurity behavior.

  6. Internal transport barrier simulation with pellet injection in tokamak and helical reactor plasmas

    NASA Astrophysics Data System (ADS)

    Higashiyama, Y.; Yamazaki, K.; Garcia, J.; Arimoto, H.; Shoji, T.

    2008-07-01

    In the future fusion reactor, the plasma density peaking is important for the increase in the fusion power gain. The density control and the internal transport barrier (ITB) formation due to the pellet injection have been simulated in tokamak and helical reactors using the toroidal transport linkage code TOTAL. Firstly, the pellet injection simulation is carried out including the neutral gas shielding model and the mass relocation model in the TOTAL code, and the effectiveness of the high field side (HFS) pellet injection is clarified. Secondly, the ITB simulation with the pellet injection is carried out with the confinement improvement model based on the E×B shear effects, and it is found that the deep pellet penetration is helpful for the ITB formation as well as the plasma core fuelling in the reversed shear tokamak reactor, but the deep pellet penetration is not effective in the helical reactor.

  7. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor fueling

    SciTech Connect

    Kim, K.; Zhang, J.

    1992-01-01

    Three separate papers are included which report research progress during this period: (1) A new railgun configuration with perforated sidewalls, (2) development of a fuseless small-bore railgun for injection of high-speed hydrogen pellets into magnetically confined plasmas, and (3) controls and diagnostics on a fuseless railgun for solid hydrogen pellet injection.

  8. A fuel pellet injector for the Microwave Tokamak Experiment (MTX)

    SciTech Connect

    Hibbs, S.M.; Allen, S.L.; Petersen, D.E.; Sewall, N.R.

    1990-09-01

    Unlike other fueling systems for magnetically confined fusion plasmas, a pellet injector can deliver many fuel gas particles to the core of the plasma, enhancing plasma confinement. We installed a new pellet injector on the MTX (formerly Alcator-O) to provide a plasma with a high core density for experiments both with and without ultrahigh-power microwave heating. Its four-barrel pellet generator is the first to be designed and built at LLNL. Based on pipe-gun'' technology originated at Oak Ridge National Laboratory (ORNL), it incorporates our structural and thermal engineering innovations and a unique control system. The pellet transport, differential vacuum-pumping stages, and fast-opening propellant valves are reused parts of the Impurity Study EXperiment (ISX) pellet injector built by ORNL. We tailored designs of all other systems and components to the MTX. Our injector launches pellets of frozen hydrogen or deuterium into the MTX, either singly or in timed bursts of up to four pellets at velocities of up to 1000 m/s. Pellet diameters range from 1.02 to 2.08 mm. A diagnostic stage measures pellet velocities and allows us to photograph the pellets in flight. We are striving to improve the injector's performance, but its operations is already very consistent and reliable.

  9. Simulation of peeling-ballooning modes with pellet injection

    SciTech Connect

    Chen, S. Y.; Huang, J.; Sun, T. T.; Tang, C. J.; Wang, Z. H.

    2014-11-15

    The influence of pellet ablation on the evolution of peeling-ballooning (P-B) modes is studied with BOUT++ code. The atoms coming from pellet ablation can significantly reshape the plasma pressure profile, so the behaviors of P-B modes and edge localized mode (ELM) are modified dramatically. This paper shows that the energy loss associated with an ELM increases substantially over that without the pellet, if the pellet is deposited at the top of the pedestal. On the contrary, for pellet deposition in the middle of the pedestal region the ELM energy loss can be less.

  10. Turbulent fluctuations during pellet injection into a dipole confined plasma torus

    NASA Astrophysics Data System (ADS)

    Garnier, D. T.; Mauel, M. E.; Roberts, T. M.; Kesner, J.; Woskov, P. P.

    2017-01-01

    We report measurements of the turbulent evolution of the plasma density profile following the fast injection of lithium pellets into the Levitated Dipole Experiment (LDX) [Boxer et al., Nat. Phys. 6, 207 (2010)]. As the pellet passes through the plasma, it provides a significant internal particle source and allows investigation of density profile evolution, turbulent relaxation, and turbulent fluctuations. The total electron number within the dipole plasma torus increases by more than a factor of three, and the central density increases by more than a factor of five. During these large changes in density, the shape of the density profile is nearly "stationary" such that the gradient of the particle number within tubes of equal magnetic flux vanishes. In comparison to the usual case, when the particle source is neutral gas at the plasma edge, the internal source from the pellet causes the toroidal phase velocity of the fluctuations to reverse and changes the average particle flux at the plasma edge. An edge particle source creates an inward turbulent pinch, but an internal particle source increases the outward turbulent particle flux. Statistical properties of the turbulence are measured by multiple microwave interferometers and by an array of probes at the edge. The spatial structures of the largest amplitude modes have long radial and toroidal wavelengths. Estimates of the local and toroidally averaged turbulent particle flux show intermittency and a non-Gaussian probability distribution function. The measured fluctuations, both before and during pellet injection, have frequency and wavenumber dispersion consistent with theoretical expectations for interchange and entropy modes excited within a dipole plasma torus having warm electrons and cool ions.

  11. Dissipation of post-disruption runaway electron plateaus by shattered pellet injection in DIII-D

    NASA Astrophysics Data System (ADS)

    Shiraki, D.; Commaux, N.; Baylor, L. R.; Cooper, C. M.; Eidietis, N. W.; Paz-Soldan, C.; Hollmann, E. M.; Moyer, R. A.

    2016-10-01

    Effective runaway electron (RE) mitigation strategies are essential for protecting ITER from the potential damage of a first wall strike. In DIII-D, shattered pellet injection (SPI) with large Ne pellets demonstrates the dissipation of post-disruption RE plateaus by collisions with high-Z impurities, while equivalently sized D2 pellets lead to a reduction of the impurity content of the background plasma, reducing RE dissipation. Varying the relative quantities of Ne /D2 in mixed species pellets shows that the effect of D2 may be dominant in determining the RE/pellet interaction. Compared with injection of the same quantity of Ne by massive gas injection, SPI achieves a similar initial RE current decay rate, but residual RE current remains after SPI. This may be due to the effects of a small quantity of D2 (used as a ``shell'' for firing of the Ne pellets) displacing high-Z impurities. These results will help guide the optimization of injection schemes and pellet compositions for the RE mitigation system in ITER. Work supported by the U.S. DOE under DE-FC02-04ER54698.

  12. Reduction of edge localized mode intensity on DIII-D by on-demand triggering with high frequency pellet injection and implications for ITER

    SciTech Connect

    Baylor, L. R.; Commaux, N.; Jernigan, T. C.; Meitner, S. J.; Combs, S. K.; Isler, R. C.; Unterberg, E. A.; Brooks, N. H.; Evans, T. E.; Leonard, A. W.; Osborne, T. H.; Parks, P. B.; Snyder, P. B.; Strait, E. J.; Fenstermacher, M. E.; Lasnier, C. J.; Moyer, R. A.; Loarte, A.; Huijsmans, G. T. A.; Futatani, S.

    2013-08-15

    The injection of small deuterium pellets at high repetition rates up to 12× the natural edge localized mode (ELM) frequency has been used to trigger high-frequency ELMs in otherwise low natural ELM frequency H-mode deuterium discharges in the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)]. The resulting pellet-triggered ELMs result in up to 12× lower energy and particle fluxes to the divertor than the natural ELMs. The plasma global energy confinement and density are not strongly affected by the pellet perturbations. The plasma core impurity density is strongly reduced with the application of the pellets. These experiments were performed with pellets injected from the low field side pellet in plasmas designed to match the ITER baseline configuration in shape and normalized β operation with input heating power just above the H-mode power threshold. Nonlinear MHD simulations of the injected pellets show that destabilization of ballooning modes by a local pressure perturbation is responsible for the pellet ELM triggering. This strongly reduced ELM intensity shows promise for exploitation in ITER to control ELM size while maintaining high plasma purity and performance.

  13. Reduction of Edge Localized Mode Intensity on DIII-D by On-demand triggering with High Frequency Pellet Injection and Implications for ITER

    SciTech Connect

    Baylor, Larry R; Commaux, Nicolas JC; Jernigan, T. C.; Meitner, Steven J; Combs, Stephen Kirk; Isler, Ralph C; Unterberg, Ezekial A; Brooks, N. H.; Evans, T. E.; Leonard, A. W.; Osborne, T. H.; Parks, P. B.; Snyder, P. B.; Strait, E. J.; Fenstermacher, M. E.; Lasnier, C. J.; Moyer, R. A.; Loarte, A.; Huijsmans, G. T.A.; Futantani, S.

    2013-01-01

    The injection of small deuterium pellets at high repetition rates up to 12 the natural edge localized mode (ELM) frequency has been used to trigger high-frequency ELMs in otherwise low natural ELM frequency H-mode deuterium discharges in the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)]. The resulting pellet-triggered ELMs result in up to 12 lower energy and particle fluxes to the divertor than the natural ELMs. The plasma global energy confinement and density are not strongly affected by the pellet perturbations. The plasma core impurity density is strongly reduced with the application of the pellets. These experiments were performed with pellets injected from the low field side pellet in plasmas designed to match the ITER baseline configuration in shape and normalized operation with input heating power just above the H-mode power threshold. Nonlinear MHD simulations of the injected pellets show that destabilization of ballooning modes by a local pressure perturbation is responsible for the pellet ELM triggering. This strongly reduced ELM intensity shows promise for exploitation in ITER to control ELM size while maintaining high plasma purity and performance.

  14. 3D Adaptive Mesh Refinement Simulations of Pellet Injection in Tokamaks

    SciTech Connect

    R. Samtaney; S.C. Jardin; P. Colella; D.F. Martin

    2003-10-20

    We present results of Adaptive Mesh Refinement (AMR) simulations of the pellet injection process, a proven method of refueling tokamaks. AMR is a computationally efficient way to provide the resolution required to simulate realistic pellet sizes relative to device dimensions. The mathematical model comprises of single-fluid MHD equations with source terms in the continuity equation along with a pellet ablation rate model. The numerical method developed is an explicit unsplit upwinding treatment of the 8-wave formulation, coupled with a MAC projection method to enforce the solenoidal property of the magnetic field. The Chombo framework is used for AMR. The role of the E x B drift in mass redistribution during inside and outside pellet injections is emphasized.

  15. Snake perturbation during pellet injection in the EAST tokamak

    NASA Astrophysics Data System (ADS)

    Yao, Xingjia; Hu, Jiansheng; Xu, Liqing; Xu, Zong; Chen, Yue; Li, Changzheng; Liu, Haiqing; Zhao, Hailing; Duan, Yanmin; Shi, Tonghui; Shen, Wei; EAST Team

    2016-11-01

    The pellet-induced snake oscillation was observed by soft x-ray (SXR) diagnostic in EAST for the first time after a fueling-sized pellet penetrated the q  =  1 surface. The snake phenomenon has a long lifetime with a helicity of m  =  1 and n  =  1. Basic behaviors of the snake, including the triggering condition, interaction with the sawtooth and snake rotation frequency, were discussed in detail by multiple core diagnostics. The snake location was also analyzed through observation of the vertical SXR arrays and raw SXR brightness profiles. It is clear that the snake resided in a broad region between the magnetic axis and the q  =  1 surface derived from equilibrium reconstruction. This investigation is beneficial for the understanding of the snake formation for EAST and future devices, like ITER and DEMO.

  16. First demonstration of laser engagement of 1-Hz-injected flying pellets and neutron generation

    PubMed Central

    Komeda, Osamu; Nishimura, Yasuhiko; Mori, Yoshitaka; Hanayama, Ryohei; Ishii, Katsuhiro; Nakayama, Suisei; Kitagawa, Yoneyoshi; Sekine, Takashi; Sato, Nakahiro; Kurita, Takashi; Kawashima, Toshiyuki; Kan, Hirofumi; Nakamura, Naoki; Kondo, Takuya; Fujine, Manabu; Azuma, Hirozumi; Motohiro, Tomoyoshi; Hioki, Tatsumi; Kakeno, Mitsutaka; Sunahara, Atsushi; Sentoku, Yasuhiko; Miura, Eisuke

    2013-01-01

    Pellet injection and repetitive laser illumination are key technologies for realizing inertial fusion energy. Numerous studies have been conducted on target suppliers, injectors, and tracking systems for flying pellet engagement. Here we for the first time demonstrate the pellet injection, counter laser beams' engagement and neutron generation. Deuterated polystyrene (CD) bead pellets, after free-falling for a distance of 18 cm at 1 Hz, are successfully engaged by two counter laser beams from a diode-pumped, ultra-intense laser HAMA. The laser energy, pulse duration, wavelength, and the intensity are 0.63 J per beam, 104 fs, and 811 nm, 4.7 × 1018 W/cm2, respectively. The irradiated pellets produce D(d,n)3He-reacted neutrons with a maximum yield of 9.5 × 104/4π sr/shot. Moreover, the laser is found out to bore a straight channel with 10 μm-diameter through the 1-mm-diameter beads. The results indicate potentially useful technologies and findings for the next step in realizing inertial fusion energy. PMID:24008696

  17. Improvement of Plasma Performance Using Carbon Pellet Injection in Large Helical Device

    NASA Astrophysics Data System (ADS)

    Shigeru, Morita; Motoshi, Goto; Kenichi, Nagaoka; Chunfeng, Dong; Hangyu, Zhou; Zhengying, Cui; Yunbo, Dong; Xiang, Gao; Katsumi, Ida; Katsunori, Ikeda; Osamu, Kaneko; Shiyao, Lin; Haruhisa, Nakano; Masaki, Osakabe; Ryuichi, Sakamoto; Yasuhiko, Takeiri; Ang, Ti; Katsuyoshi, Tsumori; Mikiro, Yoshinuma; LHD experiment Group

    2011-06-01

    A cylindrical carbon pellet with a size of 1.2L × 1.2varphi mm to 1.8L × 1.8varphi mm and a velocity of 100 m/s to 300 m/s was injected into large helical device (LHD) for an efficient fueling based on its deeper deposition instead of hydrogen gas puffing and ice pellet injection. Electron density increment of Δne = 1014 cm-3 is successfully obtained by single carbon pellet injection without plasma collapse. Typical density and temperature of the ablation plasma of the carbon pellet, e.g., 6.5 × 1016 cm-3 and 2.5 eV for CII, are examined respectively by spectroscopic method. A confinement improvement up to 50% compared to ISS-95 stellarator scaling is clearly observed in a relatively low-density regime of ne = 2×1013 cm-3 to 4×1013 cm-3, and high ion temperature Ti(0) of about 6 keV is also observed with an internal transport barrier at ne = 1.2×1013 cm-3. In particular, the improvement in the ion temperature largely exceeds that observed in hydrogen gas-puffed discharges, which typically ranges below 3 keV.

  18. Development of a Twin-Screw D-2 Extruder for the ITER Pellet Injection System

    SciTech Connect

    Meitner, Steven J; Baylor, Larry R; Carbajo, Juan J; Combs, Stephen Kirk; Fehling, Dan T; Foust, Charles R; McFee, Marshall T; McGill, James M; Rasmussen, David A; Sitterson, R G; Sparks, Dennis O; Qualls, A L

    2009-07-01

    A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. The extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with single-stage gas gun into the plasma. A one-fifth ITER scale prototype extruder has been built to produce a continuous solid deuterium extrusion. Deuterium gas is precooled and liquefied before being introduced into the extruder. The precooler consists of a copper vessel containing liquid nitrogen surrounded by a deuterium gas filled copper coil. The liquefier is comprised of a copper cylinder connected to a Cryomech AL330 cryocooler, which is surrounded by a copper coil that the precooled deuterium flows through. The lower extruder barrel is connected to a Cryomech GB-37 cryocooler to solidify the deuterium (at approximate to 15 K) before it is forced through the extruder nozzle. A viewport located below the extruder nozzle provides a direct view of the extrusion. A camera is used to document the extrusion quality and duration. A data acquisition system records the extruder temperatures, torque, and speed, upstream, and downstream pressures. This paper will describe the prototype twin-screw extruder and initial extrusion results.

  19. Coaxial pellets for metallic impurity injection on the large helical device

    SciTech Connect

    Huang, X. L. Zhang, H. M.; Morita, S.; Oishi, T.; Goto, M.

    2014-11-15

    Two coaxial pellets with tungsten inserted into graphite carbon and polyethylene (PE) tubes are compared for tungsten spectroscopic study in the Large Helical Device. The tungsten pellet with carbon tube causes plasma collapse, while that with PE tube smoothly ablates without collapse. The deposition profile of the pellets is analyzed with a help of pellet ablation spectroscopy. It is found that the tungsten pellet with carbon tube can significantly penetrate into the core plasma and leads to the plasma collapse. A tungsten spectrum with radial profile is successfully observed when the tungsten pellet with PE tube is used.

  20. SNS Injection Foil Experience

    SciTech Connect

    Cousineau, Sarah M; Galambos, John D; Kim, Sang-Ho; Ladd, Peter; Luck, Chris; Peters, Charles C; Polsky, Yarom; Shaw, Robert W; Macek, Robert James; Raparia, Deepak; Plum, Michael A

    2010-01-01

    The Spallation Neutron Source comprises a 1 GeV, 1.4 MW linear accelerator followed by an accumulator ring and a liquid mercury target. To manage the beam loss caused by the H0 excited states created during the H charge exchange injection into the accumulator ring, the stripper foil is located inside one of the chicane dipoles. This has some interesting consequences that were not fully appreciated until the beam power reached about 840 kW. One consequence was sudden failure of the stripper foil system due to convoy electrons stripped from the incoming H beam, which circled around to strike the foil bracket and cause bracket failure. Another consequence is that convoy electrons can reflect back up from the electron catcher and strike the foil and bracket. An additional contributor to foil system failure is vacuum breakdown due to the charge developed on the foil by secondary electron emission. In this paper we will detail these and other interesting failure mechanisms, and describe the improvements we have made to mitigate them.

  1. A new method on recycling coefficient measurement using impurity pellet injection in a large helical device

    SciTech Connect

    Nozato, Hideaki; Morita, Shigeru; Goto, Motoshi

    2005-07-15

    Recycling coefficients of carbon, aluminum, and titanium were evaluated using a new technique combining impurity pellet injection with high-spatial resolution bremsstrahlung measurement in hydrogen and helium plasmas on the large helical device. The recycling coefficient of impurities was investigated by measuring absolute intensities with the visible bremsstrahlung array. The time evolution of the bremsstrahlung signals was modeled by an impurity transport code adjusting the diffusion coefficient, convective velocity, and recycling coefficient. As a result, a finite value of the recycling coefficient was required in the case of carbon, whereas aluminum and titanium were explained as nonrecycled particles. It was also clarified that the recycling coefficient of carbon had a larger value in hydrogen plasmas (R=0.5-0.65) than in helium plasmas (R=0-0.2), suggesting the formation of hydrogen molecules.

  2. Color measurement of plastics - From compounding via pelletizing, up to injection molding and extrusion

    NASA Astrophysics Data System (ADS)

    Botos, J.; Murail, N.; Heidemeyer, P.; Kretschmer, K.; Ulmer, B.; Zentgraf, T.; Bastian, M.; Hochrein, T.

    2014-05-01

    The typical offline color measurement on injection molded or pressed specimens is a very expensive and time-consuming process. In order to optimize the productivity and quality, it is desirable to measure the color already during the production. Therefore several systems have been developed to monitor the color e.g. on melts, strands, pellets, the extrudate or injection molded part already during the process. Different kinds of inline, online and atline methods with their respective advantages and disadvantages will be compared. The criteria are e.g. the testing time, which ranges from real-time to some minutes, the required calibration procedure, the spectral resolution and the final measuring precision. The latter ranges between 0.05 to 0.5 in the CIE L*a*b* system depending on the particular measurement system. Due to the high temperatures in typical plastics processes thermochromism of polymers and dyes has to be taken into account. This effect can influence the color value in the magnitude of some 10% and is barely understood so far. Different suitable methods to compensate thermochromic effects during compounding or injection molding by using calibration curves or artificial neural networks are presented. Furthermore it is even possible to control the color during extrusion and compounding almost in real-time. The goal is a specific developed software for adjusting the color recipe automatically with the final objective of a closed-loop control.

  3. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor fueling. Progress report, August 16, 1991--September 30, 1992

    SciTech Connect

    Kim, K.; Zhang, J.

    1992-12-01

    Three separate papers are included which report research progress during this period: (1) A new railgun configuration with perforated sidewalls, (2) development of a fuseless small-bore railgun for injection of high-speed hydrogen pellets into magnetically confined plasmas, and (3) controls and diagnostics on a fuseless railgun for solid hydrogen pellet injection.

  4. First demonstration of rapid shutdown using neon shattered pellet injection for thermal quench mitigation on DIII-D

    NASA Astrophysics Data System (ADS)

    Commaux, N.; Shiraki, D.; Baylor, L. R.; Hollmann, E. M.; Eidietis, N. W.; Lasnier, C. J.; Moyer, R. A.; Jernigan, T. C.; Meitner, S. J.; Combs, S. K.; Foust, C. R.

    2016-04-01

    Shattered pellet injection (SPI) is one of the prime candidates for the ITER disruption mitigation system because of its deeper penetration and larger particle flux than massive gas injection (MGI) (Taylor et al 1999 Phys. Plasmas 6 1872) using deuterium (Commaux et al 2010 Nucl. Fusion 50 112001, Combs et al 2010 IEEE Trans. Plasma Sci. 38 400, Baylor et al 2009 Nucl. Fusion 49 085013). The ITER disruption mitigation system will likely use mostly high Z species such as neon because of more effective thermal mitigation and pumping constraints on the maximum amount of deuterium or helium that could be injected. An upgrade of the SPI on DIII-D enables ITER relevant injection characteristics in terms of quantities and gas species. This upgraded SPI system was used on DIII-D for the first time in 2014 for a direct comparison with MGI using identical quantities of neon. This comparison enabled the measurements of density perturbations during the thermal quench (TQ) and radiated power and heat loads to the divertor. It showed that SPI using similar quantities of neon provided a faster and stronger density perturbation and neon assimilation, which resulted in a lower conducted energy to the divertor and a faster TQ onset. Radiated power data analysis shows that this was probably due to the much deeper penetration of the neon in the plasma inducing a higher core radiation than in the MGI case. This experiment shows also that the MHD activity during an SPI shutdown (especially during the TQ) is quite different compared to MGI. This favorable TQ energy dissipation was obtained while keeping the current quench (CQ) duration within acceptable limits when scaled to ITER.

  5. First demonstration of rapid shutdown using neon shattered pellet injection for thermal quench mitigation on DIII-D

    DOE PAGES

    Commaux, Nicolas J. C.; Shiraki, Daisuke; Baylor, Larry R.; ...

    2016-03-02

    Shattered pellet injection (SPI) is one of the prime candidates for the ITER disruption mitigation system because of its deeper penetration and larger particle flux than massive gas injection (MGI) (Taylor et al 1999 Phys. Plasmas 6 1872) using deuterium (Commaux et al 2010 Nucl. Fusion 50 112001, Combs et al 2010 IEEE Trans. Plasma Sci. 38 400, Baylor et al 2009 Nucl. Fusion 49 085013). The ITER disruption mitigation system will likely use mostly high Z species such as neon because of more effective thermal mitigation and pumping constraints on the maximum amount of deuterium or helium that couldmore » be injected. An upgrade of the SPI on DIII-D enables ITER relevant injection characteristics in terms of quantities and gas species. This upgraded SPI system was used on DIII-D for the first time in 2014 for a direct comparison with MGI using identical quantities of neon. This comparison enabled the measurements of density perturbations during the thermal quench (TQ) and radiated power and heat loads to the divertor. It showed that SPI using similar quantities of neon provided a faster and stronger density perturbation and neon assimilation, which resulted in a lower conducted energy to the divertor and a faster TQ onset. Radiated power data analysis shows that this was probably due to the much deeper penetration of the neon in the plasma inducing a higher core radiation than in the MGI case. This experiment shows also that the MHD activity during an SPI shutdown (especially during the TQ) is quite different compared to MGI. Furthermore, this favorable TQ energy dissipation was obtained while keeping the current quench (CQ) duration within acceptable limits when scaled to ITER.« less

  6. 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.

  7. High throughput ultrasoft x-ray polychromator for embedded impurity pellet injection studies

    SciTech Connect

    Stutman, D.; Finkenthal, M.; Delgado-Aparicio, L.; Tritz, K.; Tamura, N.; Kalinina, D.; Matsubara, A.; Sato, K.; Sudo, S.

    2005-01-01

    A prototype ultrasoft x-ray polychromator has been developed for local particle transport measurements in magnetic fusion devices using the H{sub {alpha}} charge exchange emission from low-Z impurity pellets. High throughput together with few cm radial resolution in the plasma are achieved using a toroidally aligned grid collimator, while a few A spectral bandpass together with strong background rejection are obtained using planar multilayer mirrors and foil filters. As high sensitivity detectors we use a new type of compact, efficient and high-gain multichannel plates. The prototype instrument has been evaluated in the laboratory and tested on the Large Helical Device in Japan. In addition to transport studies, this type of device is of interest for next step experiments, where high beam energy and strong attenuation will make visible charge exchange recombination spectroscopy difficult.

  8. Injection barrel with a tapered structure for a low speed and small size cryogenic hydrogen pellet in medium-sized plasma fusion devices

    NASA Astrophysics Data System (ADS)

    Motojima, G.; Sakamoto, R.; Okada, H.; Nagasaki, K.; Yamada, H.; Nakamura, Y.; Kado, S.; Kobayashi, S.; Konoshima, S.; Minami, T.; Ohshima, S.; Yamamoto, S.; Mizuuchi, T.; Mutoh, T.

    2016-10-01

    An injection barrel was designed and fabricated for a small size 0.8 mm cryogenic pellet with a low speed of 200-300 m/s in medium-sized plasma fusion devices. Pellet injection with pneumatic acceleration was examined using a conventional in situ technique. A tapered structure was applied in the downstream side of the injection barrel to satisfy the requirement of pellet speed reduction by expansion of the propellant gas. Shadowgraph and light gate measurements show that the intact pellets have speeds of 260 ± 30 m/s and a typical size of 1.1-1.2 mm. The pellet ablation code based on a neutral gas shielding model shows that the penetration depth of the measured pellet parameters does not cross the plasma center, even in medium-sized plasma devices such as the Heliotron J helical device. The injection barrel with a tapered structure developed in this study is feasible for low speed pellet injection.

  9. Experiments on torrefied wood pellet: study by gasification and characterization for waste biomass to energy applications

    PubMed Central

    Rollinson, Andrew N.; Williams, Orla

    2016-01-01

    Samples of torrefied wood pellet produced by low-temperature microwave pyrolysis were tested through a series of experiments relevant to present and near future waste to energy conversion technologies. Operational performance was assessed using a modern small-scale downdraft gasifier. Owing to the pellet's shape and surface hardness, excellent flow characteristics were observed. The torrefied pellet had a high energy density, and although a beneficial property, this highlighted the present inflexibility of downdraft gasifiers in respect of feedstock tolerance due to the inability to contain very high temperatures inside the reactor during operation. Analyses indicated that the torrefaction process had not significantly altered inherent kinetic properties to a great extent; however, both activation energy and pre-exponential factor were slightly higher than virgin biomass from which the pellet was derived. Thermogravimetric analysis-derived reaction kinetics (CO2 gasification), bomb calorimetry, proximate and ultimate analyses, and the Bond Work Index grindability test provided a more comprehensive characterization of the torrefied pellet's suitability as a fuel for gasification and also other combustion applications. It exhibited significant improvements in grindability energy demand and particle size control compared to other non-treated and thermally treated biomass pellets, along with a high calorific value, and excellent resistance to water. PMID:27293776

  10. Experiments on torrefied wood pellet: study by gasification and characterization for waste biomass to energy applications.

    PubMed

    Rollinson, Andrew N; Williams, Orla

    2016-05-01

    Samples of torrefied wood pellet produced by low-temperature microwave pyrolysis were tested through a series of experiments relevant to present and near future waste to energy conversion technologies. Operational performance was assessed using a modern small-scale downdraft gasifier. Owing to the pellet's shape and surface hardness, excellent flow characteristics were observed. The torrefied pellet had a high energy density, and although a beneficial property, this highlighted the present inflexibility of downdraft gasifiers in respect of feedstock tolerance due to the inability to contain very high temperatures inside the reactor during operation. Analyses indicated that the torrefaction process had not significantly altered inherent kinetic properties to a great extent; however, both activation energy and pre-exponential factor were slightly higher than virgin biomass from which the pellet was derived. Thermogravimetric analysis-derived reaction kinetics (CO2 gasification), bomb calorimetry, proximate and ultimate analyses, and the Bond Work Index grindability test provided a more comprehensive characterization of the torrefied pellet's suitability as a fuel for gasification and also other combustion applications. It exhibited significant improvements in grindability energy demand and particle size control compared to other non-treated and thermally treated biomass pellets, along with a high calorific value, and excellent resistance to water.

  11. Experiments on torrefied wood pellet: study by gasification and characterization for waste biomass to energy applications

    NASA Astrophysics Data System (ADS)

    Rollinson, Andrew N.; Williams, Orla

    2016-05-01

    Samples of torrefied wood pellet produced by low-temperature microwave pyrolysis were tested through a series of experiments relevant to present and near future waste to energy conversion technologies. Operational performance was assessed using a modern small-scale downdraft gasifier. Owing to the pellet's shape and surface hardness, excellent flow characteristics were observed. The torrefied pellet had a high energy density, and although a beneficial property, this highlighted the present inflexibility of downdraft gasifiers in respect of feedstock tolerance due to the inability to contain very high temperatures inside the reactor during operation. Analyses indicated that the torrefaction process had not significantly altered inherent kinetic properties to a great extent; however, both activation energy and pre-exponential factor were slightly higher than virgin biomass from which the pellet was derived. Thermogravimetric analysis-derived reaction kinetics (CO2 gasification), bomb calorimetry, proximate and ultimate analyses, and the Bond Work Index grindability test provided a more comprehensive characterization of the torrefied pellet's suitability as a fuel for gasification and also other combustion applications. It exhibited significant improvements in grindability energy demand and particle size control compared to other non-treated and thermally treated biomass pellets, along with a high calorific value, and excellent resistance to water.

  12. Transport simulations of ohmic pellet experiments on the TFTR, ASDEX, and ALCATOR-C tokamaks

    SciTech Connect

    Redi, M.H.; Tang, W.M.; Owens, D.K.; Greenwald, M.; Gruber, O.; Kaufmann, M.

    1988-07-01

    Transport simulations of ohmic gas-fuelled and pellet-fuelled experiments have been carried out to test a microinstability-based, profile-consistent model of anomalous transport in tokamaks. Predictions for experiments on the TFTR, ASDEX, and ALCATOR-C tokamaks were found consistent with the observed confinement and temperature measurements. 26 refs., 11 figs., 10 tabs.

  13. Pellet ablation and temperature profile measurements in TFTR

    SciTech Connect

    Owens, D.K.; Schmidt, G.L.; Cavallo, A.; Grek, B.; Hulse, R.; Johnson, D.; Mansfield, D.; McNeill, D.; Park, H.; Taylor, G.

    1988-01-01

    Single and multiple deuterium pellets have been injected into a variety of TFTR plasmas, including ohmically heated plasmas with wide range of electron temperatures, neutral beam heated plasmas at several NBI powers and high T/sub e/, post NBI plasmas. Pellet penetration into these plasmas was determined by measuring the pellet speed and duration of the H/sub ..cap alpha..//D/sub ..cap alpha../ light emission during pellet ablation in the plasma. These penetration measurements are compared to the predicted penetration computed using the ablation model developed by Oak Ridge National Laboratory. The plasma density profiles before and after pellet injection are used to estimate the number of particles deposited in the plasma. The plasma particle increase compared to the estimated number of atoms in the pellet yields a measure of the fueling efficiency of pellets in TFTR. The ablation cloud parameters are discussed based on polychromater measurements of the H/sub ..cap alpha..//D/sub ..cap alpha../ line emission from the neutral cloud surrounding the pellet. The electron temperature profile evolution after pellet injection is examined for the case of multiple pellet injection into an ohmically heated plasma. The ORNL pellet ablation code was used to compare measured pellet penetration depths with a theoretical model. The measured input parameters to the model are the electron density and temperature profiles, the neutral beam heating profile, the neutral density profile, the pellet size, pellet speed and pellet composition. The free parameter in the model is the thickness of the neutral cloud surrounding the pellet. This parameter is adjusted to arrive at a reasonable agreement between measured and calculated pellet penetration depths. The output of the model which is directly comparable to experiment is the calculated ablation rate. It is assumed that the broad-band H/sub ..cap alpha..//D/sub ..cap alpha../ emission is proportional to the ablation rate.

  14. Mitigation of divertor heat flux by high-frequency ELM pacing with non-fuel pellet injection in DIII-D

    DOE PAGES

    Bortolon, A.; Maingi, R.; Mansfield, D. K.; ...

    2017-03-23

    Experiments have been conducted on DIII-D investigating high repetition rate injection of non-fuel pellets as a tool for pacing Edge Localized Modes (ELMs) and mitigating their transient divertor heat loads. Effective ELM pacing was obtained with injection of Li granules in different H-mode scenarios, at frequencies 3–5 times larger than the natural ELM frequency, with subsequent reduction of strike-point heat flux. However, in scenarios with high pedestal density (~6 × 1019 m–3), the magnitude of granule triggered ELMs shows a broad distribution, in terms of stored energy loss and peak heat flux, challenging the effectiveness of ELM mitigation. Furthermore, transientmore » heat-flux deposition correlated with granule injections was observed far from the strike-points. As a result, field line tracing suggest this phenomenon to be consistent with particle loss into the mid-plane far scrape-off layer, at toroidal location of the granule injection.« less

  15. Formulation Optimization of Hot Melt Extruded Abuse Deterrent Pellet Dosage Form Utilizing Design of Experiments (DOE)

    PubMed Central

    Maddineni, Sindhuri; Battu, Sunil Kumar; Morott, Joe; Majumdar, Soumyajit; Repka, Michael A.

    2014-01-01

    The objective of the present study was to develop techniques for an abuse-deterrent (AD) platform utilizing hot melt extrusion (HME) process. Formulation optimization was accomplished by utilizing Box-Behnken design of experiments to determine the effect of the three formulation factors: PolyOx™ WSR301, Benecel™ K15M, and Carbopol 71G; each of which was studied at three levels on TR attributes of the produced melt extruded pellets. A response surface methodology was utilized to identify the optimized formulation. Lidocaine Hydrochloride was used as a model drug, and suitable formulation ingredients were employed as carrier matrices and processing aids. All of the formulations were evaluated for the TR attributes such as particle size post-milling, gelling, percentage of drug extraction in water and alcohol. All of the DOE formulations demonstrated sufficient hardness and elasticity, and could not be reduced into fine particles (<150µm), which is a desirable feature to prevent snorting. In addition, all of the formulations exhibited good gelling tendency in water with minimal extraction of drug in the aqueous medium. Moreover, Benecel™ K15M in combination with PolyOx™ WSR301 could be utilized to produce pellets with TR potential. HME has been demonstrated to be a viable technique with a potential to develop novel abuse-deterrent formulations. PMID:24433429

  16. Development of a new tracer-encapsulated solid pellet injection system for more precise control of tracer-impurity-deposit location in LHD

    NASA Astrophysics Data System (ADS)

    Tamura, N.; Shoji, M.; Suzuki, C.; Funaba, H.; Hayashi, H.; Maeno, H.; Yokota, M.; Ogawa, H.; Sudo, S.

    2016-11-01

    A new tracer-encapsulated solid pellet (TESPEL) injection system has been developed additionally for the LHD heliotron. This system has three-dimensionally bended guide tubes, which allows us to inject the TESPEL obliquely on a poloidal cross-section of the LHD plasma. Consequently, this system enables us to control a tracer-impurity-deposited location more precisely. Moreover, this system can make it possible for the tracer impurity to be deposited even only inside the ergodic region (outside a last closed flux surface of the LHD plasma). A stereoscopic fast camera system has been also developed for capturing a three-dimensional TESPEL trajectory.

  17. Testosterone Injection

    MedlinePlus

    ... and testosterone pellet (Testopel) are forms of testosterone injection used to treat symptoms of low testosterone in ... are low before you begin to use testosterone injection. Testosterone enanthate (Delatestryl) and testosterone pellet (Testopel) are ...

  18. Application of the design of experiments in optimization of drug layering of pellets with an insight into drug polymer interactions.

    PubMed

    Kovacevic, Jovana; Ibric, Svetlana; Djuris, Jelena; Kleinebudde, Peter

    2016-06-15

    This study consists of two experimental designs. Within the first one, suitable technique for application of model drug onto inactive pellets was evaluated and formulation and process parameters with greatest impact to process efficency and useful yield were determined. Results of experiments showed that formulation characteristics were the ones with the greatest impact on coating efficiency and that suspension layering technique was significantly better for drug application onto inactive pellets in comparison to solution layering during which pronounced agglomeration of pellets occurred. Analysis of drug-polymer interactions by differential scanning calorimetry was performed to explain the results of experiments. The reason for agglomeration of pellets during solution layering was formation of low Tg amorphous form of model drug. The second set of experiments was performed according to central composite design experimental plan in order to optimize level of binder and concentration of solids in the coating liquid which were found to have greatest positive impact on process efficiency and useful yield in the screening study. Statistically significant models were obtained by response surface methodology and it was possible to use them to define optimal levels of excipients in the formulation.

  19. Runaway electron production in DIII-D killer pellet experiments, calculated with the CQL3D/KPRAD model

    SciTech Connect

    Harvey, R. W.; Chan, V. S.; Chiu, S. C.; Evans, T. E.; Rosenbluth, M. N.; Whyte, D. G.

    2000-11-01

    Runaway electrons are calculated to be produced during the rapid plasma cooling resulting from ''killer pellet'' injection experiments, in general agreement with observations in the DIII-D [J. L. Luxon , Plasma Physics and Controlled Nuclear Fusion Research 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] tokamak. The time-dependent dynamics of the kinetic runaway distributions are obtained with the CQL3D [R. W. Harvey and M. G. McCoy, ''The CQL3D Code,'' in Proceedings of the IAEA Technical Committee Meeting on Numerical Modeling, Montreal, 1992 (International Atomic Energy Agency, Vienna, 1992), p. 489] collisional Fokker--Planck code, including the effect of small and large angle collisions and stochastic magnetic field transport losses. The background density, temperature, and Z{sub eff} are evolved according to the KPRAD [D. G. Whyte and T. E. Evans , in Proceedings of the 24th European Conference on Controlled Fusion and Plasma Physics, Berchtesgaden, Germany (European Physical Society, Petit-Lancy, 1997), Vol. 21A, p. 1137] deposition and radiation model of pellet--plasma interactions. Three distinct runway mechanisms are apparent: (1) prompt ''hot-tail runaways'' due to the residual hot electron tail remaining from the pre-cooling phase, (2) ''knock-on'' runaways produced by large-angle Coulomb collisions on existing high energy electrons, and (3) Dreicer ''drizzle'' runaway electrons due to diffusion of electrons up to the critical velocity for electron runaway. For electron densities below {approx}1x10{sup 15}cm{sup -3}, the hot-tail runaways dominate the early time evolution, and provide the seed population for late time knock-on runaway avalanche. For small enough stochastic magnetic field transport losses, the knock-on production of electrons balances the losses at late times. For losses due to radial magnetic field perturbations in excess of {approx}0.1% of the background field, i.e., {delta}B{sub r}/B{>=}0.001, the losses

  20. Drug release from MCC- and carrageenan-based pellets: experiment and theory.

    PubMed

    Kranz, H; Jürgens, K; Pinier, M; Siepmann, J

    2009-10-01

    Microcrystalline cellulose (MCC) is a well-established pelletisation aid. However, MCC pellets generally do not disintegrate, resulting in prolonged drug release, especially in the case of drugs with poor/low aqueous solubility. The major objectives of this study were (i) to modify the prolonged matrix-type drug release from MCC pellets by addition of a disintegrant (croscarmellose Na) or pore former (PEG 6000), (ii) to evaluate carrageenan as potential alternative pelletisation aid for manufacturing high-dose immediate release pellets, and (iii) to better understand the underlying drug release mechanisms. Pellets containing 77-90% drug with poor/low aqueous solubility (vatalanib succinate, SAG/ZK, or theophylline) were prepared by extrusion-spheronisation. All batches showed acceptable yields, aspect ratios, tensile strengths, and porosities. Drug release from MCC pellets was predominantly controlled by pure diffusion and limited drug solubility and could be quantitatively described using Fick's law. Importantly, the apparent drug diffusivity could effectively be adjusted by adding small amounts of a disintegrant or pore former, allowing for release periods ranging from a few minutes to several hours. The drug diffusion coefficients varied between 0.36 and 29 x 10(-6)cm(2)/s. In contrast, carrageenan-based pellets very rapidly disintegrated upon contact with aqueous media and released high doses of drugs with poor/low aqueous solubility within a few minutes.

  1. Swelling under irradiation of MgO pellets containing americium oxide: The ECRIX-H irradiation experiment

    NASA Astrophysics Data System (ADS)

    Lamontagne, J.; Béjaoui, S.; Hanifi, K.; Valot, Ch.; Loubet, L.

    2011-06-01

    The ECRIX-H irradiation experiment studied the behaviour of pellets containing americium dispersed in MgO. The purpose of the irradiation was to demonstrate the capacity of magnesia to provide an efficient support matrix. After fabrication, the sintered pellets contained 16.65 wt.% of Am microdispersed in the inert matrix. The ECRIX-H pellets were irradiated under a locally moderated neutron flux in the Phénix sodium-cooled fast reactor (SFR) for 318 Effective Full Power Days (EFPD). Post-test calculations indicated that the fission and transmutation rates of americium at the maximum flux plane reached 33.9% and 92.6% respectively at the end of the irradiation phase. The results of the post-irradiation examinations - both non-destructive and destructive - are discussed in this paper. These results indicate a satisfactory behaviour of the MgO matrix. Particularly, a moderate swelling occurs in the pellets under irradiation even with significant quantities of helium generated and at high transmutation rate.

  2. Modeling pellet impact drilling process

    NASA Astrophysics Data System (ADS)

    Kovalyov, A. V.; Ryabchikov, S. Ya; Isaev, Ye D.; Ulyanova, O. S.

    2016-03-01

    The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rocks. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The experiments conducted has allowed modeling the process of pellet impact drilling, which creates the scientific and methodological basis for engineering design of drilling operations under different geo-technical conditions.

  3. BWR fuel experience with zinc injection

    SciTech Connect

    Levin, H.A.; Garcia, S.E.

    1995-12-31

    In 1982 a correlation between low primary recirculation system dose rates in BWR`s and the presence of ionic zinc in reactor water was identified. The source of the zinc was primarily from Admiralty brass condensers. Plants with brass condensers are called ``natural zinc`` plants. Brass condensers were also a source of copper that was implicated in crude induced localized corrosion (CILC) fuel failures. In 1986 the first BWR intentionally injected zinc for the benefits of dose rate control. Although zinc alone was never implicated in fuel degradation of failures, a comprehensive fuel surveillance program was initiated to monitor fuel performance. Currently there are 14 plants that are injecting zinc. Six of these plants are also on hydrogen water chemistry. This paper describes the effect on both Zircaloy corrosion and the cruding characteristics as a result of these changes in water chemistry. Fuel rod corrosion was found to be independent of the specific water chemistry of the plants. The corrosion behavior was the same with the additions of zinc alone or zinc plus hydrogen and well within the operating experience for fuel without either of these additions. No change was observed in the amounts of crude deposited on the fuel rods, both for the adherent and loosely held deposits. One of the effects of the zinc addition was the trend to form more of the zinc rich iron spinel in the fuel deposits rather than the hematite deposits that are predominantly formed with non additive water chemistry.

  4. Owl Pellets.

    ERIC Educational Resources Information Center

    Thompson, Craig D.

    1987-01-01

    Provides complete Project WILD lesson plans for 20-45-minute experiential science learning activity for grades 3-7 students. Describes how students construct a simple food chain through examination of owl pellets. Includes lesson objective, method, background information, materials, procedure, evaluation, and sources of owl pellets and posters.…

  5. Pelletizing lignite

    DOEpatents

    Goksel, Mehmet A.

    1983-11-01

    Lignite is formed into high strength pellets having a calorific value of at least 9,500 Btu/lb by blending a sufficient amount of an aqueous base bituminous emulsion with finely-divided raw lignite containing its inherent moisture to form a moistened green mixture containing at least 3 weight % of the bituminous material, based on the total dry weight of the solids, pelletizing the green mixture into discrete green pellets of a predetermined average diameter and drying the green pellets to a predetermined moisture content, preferrably no less than about 5 weight %. Lignite char and mixture of raw lignite and lignite char can be formed into high strength pellets in the same general manner.

  6. The enhanced ASDEX Upgrade pellet centrifuge launcher.

    PubMed

    Plöckl, B; Lang, P T

    2013-10-01

    Pellets played an important role in the program of ASDEX Upgrade serving both for investigations on efficient particle fuelling and high density scenarios but also for pioneering work on Edge Localised Mode (ELM) pacing and mitigation. Initially designed for launching fuelling pellets from the magnetic low field side, the system was converted already some time ago to inject pellets from the magnetic high field side as much higher fuelling efficiency was found using this configuration. In operation for more than 20 years, the pellet launching system had to undergo a major revision and upgrading, in particular of its control system. Furthermore, the control system installed adjacent to the launcher had to be transferred to a more distant location enforcing a complete galvanic separation from torus potential and a fully remote control solution. Changing from a hybrid system consisting of PLC S5/S7 and some hard wired relay control to a state of the art PLC system allowed the introduction of several new operational options enabling more flexibility in the pellet experiments. This article describes the new system architecture of control hardware and software, the operating procedure, and the extended operational window. First successful applications for ELM pacing and triggering studies are presented as well as utilization for the development of high density scenarios.

  7. The enhanced ASDEX Upgrade pellet centrifuge launcher

    NASA Astrophysics Data System (ADS)

    Plöckl, B.; Lang, P. T.

    2013-10-01

    Pellets played an important role in the program of ASDEX Upgrade serving both for investigations on efficient particle fuelling and high density scenarios but also for pioneering work on Edge Localised Mode (ELM) pacing and mitigation. Initially designed for launching fuelling pellets from the magnetic low field side, the system was converted already some time ago to inject pellets from the magnetic high field side as much higher fuelling efficiency was found using this configuration. In operation for more than 20 years, the pellet launching system had to undergo a major revision and upgrading, in particular of its control system. Furthermore, the control system installed adjacent to the launcher had to be transferred to a more distant location enforcing a complete galvanic separation from torus potential and a fully remote control solution. Changing from a hybrid system consisting of PLC S5/S7 and some hard wired relay control to a state of the art PLC system allowed the introduction of several new operational options enabling more flexibility in the pellet experiments. This article describes the new system architecture of control hardware and software, the operating procedure, and the extended operational window. First successful applications for ELM pacing and triggering studies are presented as well as utilization for the development of high density scenarios.

  8. The enhanced ASDEX Upgrade pellet centrifuge launcher

    SciTech Connect

    Plöckl, B.; Lang, P. T.

    2013-10-15

    Pellets played an important role in the program of ASDEX Upgrade serving both for investigations on efficient particle fuelling and high density scenarios but also for pioneering work on Edge Localised Mode (ELM) pacing and mitigation. Initially designed for launching fuelling pellets from the magnetic low field side, the system was converted already some time ago to inject pellets from the magnetic high field side as much higher fuelling efficiency was found using this configuration. In operation for more than 20 years, the pellet launching system had to undergo a major revision and upgrading, in particular of its control system. Furthermore, the control system installed adjacent to the launcher had to be transferred to a more distant location enforcing a complete galvanic separation from torus potential and a fully remote control solution. Changing from a hybrid system consisting of PLC S5/S7 and some hard wired relay control to a state of the art PLC system allowed the introduction of several new operational options enabling more flexibility in the pellet experiments. This article describes the new system architecture of control hardware and software, the operating procedure, and the extended operational window. First successful applications for ELM pacing and triggering studies are presented as well as utilization for the development of high density scenarios.

  9. Natural attenuation of xenobiotic compounds: Anaerobic field injection experiment

    SciTech Connect

    Ruegge, K.; Bjerg, P.L.; Mosbaek, H.; Christensen, T.H.

    1995-12-31

    Currently, a continuous field injection experiment is being performed in the anaerobic part of a pollution plume downgradient of the Grindsted Landfill in Denmark. This natural gradient experiment includes an injection of 18 different xenobiotic compounds with bromide as a tracer. The injection is taking place under methanogenic/sulfate-reducing conditions and the compounds will, as they migrate with the groundwater, pass through a zone where the redox conditions have been determined as iron-reducing.

  10. Pellet Puzzlers.

    ERIC Educational Resources Information Center

    Hoots, R. A.

    1992-01-01

    Presents information on owl's taxonomy, characteristics, and influences on man. Describes owl pellets, which are digestive discards, and explains how they can be used to determine the owl's diet as a science activity. (PR)

  11. Speed limit of frozen pellets (H{sub 2}, D{sub 2}, and Ne) through single-loop and multiloop tubes and implications for fusion plasma research

    SciTech Connect

    Combs, S. K.; Griffith, A. E.; Foust, C. R.

    2001-01-01

    Frozen pellets (H{sub 2}, D{sub 2}, and Ne at 8 K) of nominal 2.7 mm diam were shot through a coiled tube (single loop of {approx}0.6 m diam and 8.5 mm bore), and the speed limit for survival was recorded for each pellet type. Intact H{sub 2} pellets were observed at speeds approaching 500 m/s; but neon pellets could not survive much more than 100 m/s. The speed limit for D{sub 2} pellets fell in the middle at {approx}300 m/s. Some D{sub 2} pellets were also shot through a 30 m coiled tube consisting of 11 loops (average loop diameter of {approx}0.8 m), and a speed limit of {approx}100 m/s was observed. Injection of frozen H{sub 2} or D{sub 2} pellets is commonly used for core fueling of magnetically confined plasmas, and frozen neon pellets are sometimes used for impurity transport studies in similar experiments. The results from these tests add to a pellet database for injection lines with single- and complex multiple-curved guide tubes. All of the information to date suggests that frozen pellets can be delivered reliably from a pellet source to any accessible plasma location on a fusion device via ''roller-coaster'' tubes as long as the pellet speed is maintained below a threshold limit.

  12. Numerical modeling of injection experiments at The Geysers

    SciTech Connect

    Pruess, Karsten; Enedy, Steve

    1993-01-28

    Data from injection experiments in the southeast Geysers are presented that show strong interference (both negative and positive) with a neighboring production well. Conceptual and numerical models are developed that explain the negative interference (decline of production rate) in terms of heat transfer limitations and water-vapor relative permeability effects. Recovery and overrecovery following injection shut-in are attributed to boiling of injected fluid, with heat of vaporization provided by the reservoir rocks.

  13. Numerical modeling of injection experiments at The Geysers

    SciTech Connect

    Pruess, K.; Enedy, S.

    1993-01-01

    Data from injection experiments in the southeast Geysers are presented that show strong interference (both negative and positive) with a neighboring production well. Conceptual and numerical models are developed that explain the negative interference (decline of production rate) in terms of heat transfer limitations and water-vapor relative permeability effects. Recovery and over-recovery following injection shut-in are attributed to boiling of injected fluid, with heat of vaporization provided by the reservoir rocks.

  14. Pellet interaction with runaway electrons

    SciTech Connect

    James, A. N.; Hollmann, E. M.; Yu, J.H.; Austin, M. E.; Commaux, Nicolas JC; Evans, T.E.; Humphrey, D. A.; Jernigan, T. C.; Parks, P. B.; Putvinski, S.; Strait, E. J.; Tynan, G. R.; Wesley, J. C.

    2011-01-01

    We describe results from recent experiments studying interaction of solid polystyrene pellets with a runaway electron current channel generated after cryogenic argon pellet rapid shutdown of DIII-D. Fast camera imaging shows the pellet trajectory and continuum emission from the subsequent explosion, with geometric calibration providing detailed explosion analysis and runaway energy. Electron cyclotron emission also occurs, associated with knock-on electrons broken free from the pellet by RE which then accelerate and runaway, and also with a short lived hot plasma blown off the pellet surface. In addition, we compare heating and explosion times from observations and a model of pellet heating and breakdown by runaway interaction. (C) 2011 Elsevier B.V. All rights reserved

  15. Twenty barrel in situ pipe gun type solid hydrogen pellet injector for the Large Helical Device.

    PubMed

    Sakamoto, Ryuichi; Motojima, Gen; Hayashi, Hiromi; Inoue, Tomoyuki; Ito, Yasuhiko; Ogawa, Hideki; Takami, Shigeyuki; Yokota, Mitsuhiro; Yamada, Hiroshi

    2013-08-01

    A 20 barrel solid hydrogen pellet injector, which is able to inject 20 cylindrical pellets with a diameter and length of between 3.0 and 3.8 mm at the velocity of 1200 m/s, has been developed for the purpose of direct core fueling in LHD (Large Helical Device). The in situ pipe gun concept with the use of compact cryo-coolers enables stable operation as a fundamental facility in plasma experiments. The combination of the two types of pellet injection timing control modes, i.e., pre-programing mode and real-time control mode, allows the build-up and sustainment of high density plasma around the density limit. The pellet injector has demonstrated stable operation characteristics during the past three years of LHD experiments.

  16. Control System for the NSTX Lithium Pellet Injector

    SciTech Connect

    P. Sichta; J. Dong; R. Gernhardt; G. Gettelfinger; H. Kugel

    2003-10-27

    The Lithium Pellet Injector (LPI) is being developed for the National Spherical Torus Experiment (NSTX). The LPI will inject ''pellets'' of various composition into the plasma in order to study wall conditioning, edge impurity transport, liquid limiter simulations, and other areas of research. The control system for the NSTX LPI has incorporated widely used advanced technologies, such as LabVIEW and PCI bus I/O boards, to create a low-cost control system which is fully integrated into the NSTX computing environment. This paper will present the hardware and software design of the computer control system for the LPI.

  17. Electrothermal plasma gun as a pellet injector

    SciTech Connect

    Kincaid, R.W.; Bourham, M.A.

    1994-11-01

    The NCSU electrothermal plasma gun SIRENS has been used to accelerate plastic (Lexan polycarbonate) pellets, to determine the feasibility of the use of electrothermal guns as pellet injectors. The use of an electrothermal gun to inject frozen hydrogenic pellets requires a mechanism to provide protective shells (sabots) for shielding the pellet from ablation during acceleration into and through the barrel of the gun. The gun has been modified to accommodate acceleration of the plastic pellets using special acceleration barrels equipped with diagnostics for velocity and position of the pellet, and targets to absorb the pellet`s energy on impact. The length of the acceleration path could be varied between 15 and 45 cm. The discharge energy of the electrothermal gun ranged from 2 to 6 kJ. The pellet velocities have been measured via a set of break wires. Pellet masses were varied between 0.5 and 1.0 grams. Preliminary results on 0.5 and 1.0 g pellets show that the exit velocity reaches 0.9 km/s at 6 kJ input energy to the source. Higher velocities of 1.5 and 2.7 km/s have been achieved using 0.5 and 1.0 gm pellets in 30 cm long barrel, without cleaning the barrel between the shots.

  18. Flux-Level Transit Injection Experiments with NASA Pleiades Supercomputer

    NASA Astrophysics Data System (ADS)

    Li, Jie; Burke, Christopher J.; Catanzarite, Joseph; Seader, Shawn; Haas, Michael R.; Batalha, Natalie; Henze, Christopher; Christiansen, Jessie; Kepler Project, NASA Advanced Supercomputing Division

    2016-06-01

    Flux-Level Transit Injection (FLTI) experiments are executed with NASA's Pleiades supercomputer for the Kepler Mission. The latest release (9.3, January 2016) of the Kepler Science Operations Center Pipeline is used in the FLTI experiments. Their purpose is to validate the Analytic Completeness Model (ACM), which can be computed for all Kepler target stars, thereby enabling exoplanet occurrence rate studies. Pleiades, a facility of NASA's Advanced Supercomputing Division, is one of the world's most powerful supercomputers and represents NASA's state-of-the-art technology. We discuss the details of implementing the FLTI experiments on the Pleiades supercomputer. For example, taking into account that ~16 injections are generated by one core of the Pleiades processors in an hour, the “shallow” FLTI experiment, in which ~2000 injections are required per target star, can be done for 16% of all Kepler target stars in about 200 hours. Stripping down the transit search to bare bones, i.e. only searching adjacent high/low periods at high/low pulse durations, makes the computationally intensive FLTI experiments affordable. The design of the FLTI experiments and the analysis of the resulting data are presented in “Validating an Analytic Completeness Model for Kepler Target Stars Based on Flux-level Transit Injection Experiments” by Catanzarite et al. (#2494058).Kepler was selected as the 10th mission of the Discovery Program. Funding for the Kepler Mission has been provided by the NASA Science Mission Directorate.

  19. Cryogenic pellet launcher adapted for controlling of tokamak plasma edge instabilities.

    PubMed

    Lang, P T; Cierpka, P; Harhausen, J; Neuhauser, J; Wittmann, C; Gál, K; Kálvin, S; Kocsis, G; Sárközi, J; Szepesi, T; Dorner, C; Kauke, G

    2007-02-01

    One of the main challenges posed recently on pellet launcher systems in fusion-oriented plasma physics is the control of the plasma edge region. Strong energy bursts ejected from the plasma due to edge localized modes (ELMs) can form a severe threat for in-vessel components but can be mitigated by sufficiently frequent triggering of the underlying instabilities using hydrogen isotope pellet injection. However, pellet injection systems developed mainly for the task of ELM control, keeping the unwanted pellet fueling minimized, are still missing. Here, we report on a novel system developed under the premise of its suitability for control and mitigation of plasma edge instabilities. The system is based on the blower gun principle and is capable of combining high repetition rates up to 143 Hz with low pellet velocities. Thus, the flexibility of the accessible injection geometry can be maximized and the pellet size kept low. As a result the new system allows for an enhancement in the tokamak operation as well as for more sophisticated experiments investigating the underlying physics of the plasma edge instabilities. This article reports on the design of the new system, its main operational characteristics as determined in extensive test bed runs, and also its first test at the tokamak experiment ASDEX Upgrade.

  20. Tritium pellet injector for TFTR

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Cole, M.J.; Combs, S.K.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foust, C.R.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Wilgen, J.B.; Schmidt, G.L.; Barnes, G.W.; Persing, R.G.

    1992-06-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) phase. The existing TFTR deuterium pellet injector (DPI) has been modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed to provide pellets ranging from 3.3 to 4.5 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller. The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed, and the TPI was tested at ORNL with deuterium pellet. Results of the limited testing program at ORNL are described. The TPI is being installed on TFTR to support the D-D run period in 1992. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and secondary tritium containment systems and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  1. Tritium pellet injector for TFTR

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Cole, M.J.; Combs, S.K.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foust, C.R.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Wilgen, J.B. ); Schmidt, G.L.; Barnes, G.W.; Persing, R.G. . Plasma Physics Lab.)

    1992-01-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) phase. The existing TFTR deuterium pellet injector (DPI) has been modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed to provide pellets ranging from 3.3 to 4.5 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller. The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed, and the TPI was tested at ORNL with deuterium pellet. Results of the limited testing program at ORNL are described. The TPI is being installed on TFTR to support the D-D run period in 1992. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and secondary tritium containment systems and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  2. Geothermal injection treatment: process chemistry, field experiences, and design options

    SciTech Connect

    Kindle, C.H.; Mercer, B.W.; Elmore, R.P.; Blair, S.C.; Myers, D.A.

    1984-09-01

    The successful development of geothermal reservoirs to generate electric power will require the injection disposal of approximately 700,000 gal/h (2.6 x 10/sup 6/ 1/h) of heat-depleted brine for every 50,000 kW of generating capacity. To maintain injectability, the spent brine must be compatible with the receiving formation. The factors that influence this brine/formation compatibility and tests to quantify them are discussed in this report. Some form of treatment will be necessary prior to injection for most situations; the process chemistry involved to avoid and/or accelerate the formation of precipitate particles is also discussed. The treatment processes, either avoidance or controlled precipitation approaches, are described in terms of their principles and demonstrated applications in the geothermal field and, when such experience is limited, in other industrial use. Monitoring techniques for tracking particulate growth, the effect of process parameters on corrosion and well injectability are presented. Examples of brine injection, preinjection treatment, and recovery from injectivity loss are examined and related to the aspects listed above.

  3. Experiments on Plume Spreading by Engineered Injection and Extraction

    NASA Astrophysics Data System (ADS)

    Mays, D. C.; Jones, M.; Tigera, R. G.; Neupauer, R.

    2014-12-01

    The notion that groundwater remediation is transport-limited emphasizes the coupling between physical (i.e., hydrodynamic), geochemical, and microbiological processes in the subsurface. Here we leverage this coupling to promote groundwater remediation using the approach of engineered injection and extraction. In this approach, inspired by the literature on chaotic advection, uncontaminated groundwater is injected and extracted through a manifold of wells surrounding the contaminated plume. The potential of this approach lies in its ability to actively manipulate the velocity field near the contaminated plume, generating plume spreading above and beyond that resulting from aquifer heterogeneity. Plume spreading, in turn, promotes mixing and reaction by chemical and biological processes. Simulations have predicted that engineered injection and extraction generates (1) chaotic advection whose characteristics depend on aquifer heterogeneity, and (2) faster rates and increased extent of groundwater remediation. This presentation focuses on a complimentary effort to experimentally demonstrate these predictions experimentally. In preparation for future work using refractive index matched (RIM) porous media, the experiments reported here use a Hele-Shaw apparatus containing silicone oil. Engineered injection and extraction is used to manipulate the geometry of an initially circular plume of black pigment, and photographs record the plume geometry after each step of injection of extraction. Image analysis, using complimentary Eulerian and Lagrangian approaches, reveals the thickness and variability of the dispersion zone surrounding the deformed plume of black pigment. The size, shape, and evolution of this dispersion zone provides insight into the interplay between engineered injection and extraction, which generates plume structure, and dispersion (here Taylor dispersion), which destroys plume structure. These experiments lay the groundwork for application of engineered

  4. Use of Ar pellet ablation rate to estimate initial runaway electron seed population in DIII-D rapid shutdown experiments

    NASA Astrophysics Data System (ADS)

    Hollmann, E. M.; Commaux, N.; Moyer, R. A.; Parks, P. B.; Austin, M. E.; Bykov, I.; Cooper, C.; Eidietis, N. W.; O'Mullane, M.; Paz-Soldan, C.; Rudakov, D. L.; Shiraki, D.

    2017-01-01

    Small (2-3 mm, 0.9-2 Pa · m3) argon pellets are used in the DIII-D tokamak to cause rapid shutdown (disruption) of discharges. The Ar pellet ablation is typically found to be much larger than expected from the thermal plasma electron temperature alone; the additional ablation is interpreted as being due to non-thermal runaway electrons (REs) formed during the pellet-induced temperature collapse. Simple estimates of the RE seed current using the enhanced ablation rate give values of order 1-10 kA, roughly consistent with estimates based on avalanche theory. Analytic estimates of the RE seed current based on the Dreicer formula tend to significantly underestimate it, while estimates based on the hot tail model significantly overestimate it.

  5. Experimental investigation of solid hydrogen pellet ablation in high-temperature plasmas using holographic interferometry and other diagnostics

    SciTech Connect

    Thomas, Jr., C. E.

    1981-03-01

    The technology currently most favored for the refueling of fusion reactors is the high-velocity injection of solid hydrogen pellets. Design details are presented for a holographic interferometer/shadowgraph used to study the microscopic characteristics of a solid hydrogen pellet ablating in an approx. 1-keV plasma. Experimental data are presented for two sets of experiments in which the interferometer/shadowgraph was used to study approx. 1-mm-diam solid hydrogen pellets injected into the Impurity Study Experiment (ISX-B) tokamak at Oak Ridge National Laboratory (ORNL) at velocities of 1000 m/s. In addition to the use of the holographic interferometer, the pellet ablation process is diagnosed by studying the emission of Balmer-alpha photons and by using the available tokamak diagnostics (Thomson scattering, microwave/far-infrared interferometer, pyroelectric radiometer, hard x-ray detector).

  6. Particle transport in pellet fueled JET (Jet European Torus) plasmas

    SciTech Connect

    Baylor, L.R.

    1990-01-01

    Pellet fueling experiments have been carried out on the Joint European Torus (JET) tokamak with a multi-pellet injector. The pellets are injected at speeds approaching 1400 m/s and penetrate deep into the JET plasma. Highly peaked electron density profiles are achieved when penetration of the pellets approaches or goes beyond the magnetic axis, and these peaked profiles persist for more than two seconds in ohmic discharges and over one second in ICRF heated discharges. In this dissertation, analysis of electron particle transport in multi-pellet fueled JET limiter plasmas under a variety of heating conditions is described. The analysis is carried out with a one and one-half dimensional radial particle transport code to model the experimental density evolution with various particle transport coefficients. These analyses are carried out in plasmas with ohmic heating, ICRF heating, and neural beam heating, in limiter configurations. Peaked density profile cases are generally characterized by diffusion coefficients with a central (r/a < 0.5) diffusivity {approximately}0.1 m{sup 2}/s that increases rapidly to {approximately}0.3 m{sup 2}/s at r/a = 0.6 and then increases out to the plasma edge as (r/a){sup 2}. These discharges can be satisfactorily modeled without any anomalous convective (pinch) flux. 79 refs., 60 figs.

  7. A fault injection experiment using the AIRLAB Diagnostic Emulation Facility

    NASA Technical Reports Server (NTRS)

    Baker, Robert; Mangum, Scott; Scheper, Charlotte

    1988-01-01

    The preparation for, conduct of, and results of a simulation based fault injection experiment conducted using the AIRLAB Diagnostic Emulation facilities is described. An objective of this experiment was to determine the effectiveness of the diagnostic self-test sequences used to uncover latent faults in a logic network providing the key fault tolerance features for a flight control computer. Another objective was to develop methods, tools, and techniques for conducting the experiment. More than 1600 faults were injected into a logic gate level model of the Data Communicator/Interstage (C/I). For each fault injected, diagnostic self-test sequences consisting of over 300 test vectors were supplied to the C/I model as inputs. For each test vector within a test sequence, the outputs from the C/I model were compared to the outputs of a fault free C/I. If the outputs differed, the fault was considered detectable for the given test vector. These results were then analyzed to determine the effectiveness of some test sequences. The results established coverage of selt-test diagnostics, identified areas in the C/I logic where the tests did not locate faults, and suggest fault latency reduction opportunities.

  8. Gas-injection experiments on a dense plasma focus

    SciTech Connect

    Barnouin, O.; Javedani, J.; Del Medico, S.; Miley, G.H.; Bromley, B.

    1994-12-31

    Rockford Technology Associates, Inc. (RTA) has been doing experiments on the Dense Plasma focus (DPF) device at the Fusion Studies Laboratory of the University of Illinois. This DPF consists of four racks of five 2-{mu}F capacitors whose charge is switched onto the inner electrode of a plasma focus by four Trigatron spark gaps. The stored energy is 12.5 kJ at 25 kV. The bank is usually discharged in a static fill of H{sub 2} at {approx} 6 torr. Preliminary experiments aimed at exploring the potential of the DPF device as a magnetoplasmadynamic (MPD) thruster and as an x-ray source for lithography have investigated various alternative ways of injecting gas between the electrodes. One of those approaches consists of injecting gas from the tip of the inner electrode at a steady rate. In this operation, the DPF chamber pressure was held constant by running the vacuum pump at full throttle. This operation simulated simultaneous pulsed injection at the base insulator and electrode tip. Hydrogen was fed through a 1/16th-inch hole at a flow rate of {approx} 90 cm/s. Pulsing was then performed at 23 kV, and the corresponding variations of the current were observed using a Rogowski coil. It is found that the plasma collapses into a pinch at the same time as in conventional experiments using a static fill. The singularity in the current waveform is slightly smaller with tip injection, but its size and shape are easily reproducible. Further details and comparison of this operation with conventional pulsing will be presented.

  9. First neutral beam injection experiments on KSTAR tokamak.

    PubMed

    Jeong, S H; Chang, D H; Kim, T S; In, S R; Lee, K W; Jin, J T; Chang, D S; Oh, B H; Bae, Y S; Kim, J S; Park, H T; Watanabe, K; Inoue, T; Kashiwagi, M; Dairaku, M; Tobari, H; Hanada, M

    2012-02-01

    The first neutral beam (NB) injection system of the Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak was partially completed in 2010 with only 1∕3 of its full design capability, and NB heating experiments were carried out during the 2010 KSTAR operation campaign. The ion source is composed of a JAEA bucket plasma generator and a KAERI large multi-aperture accelerator assembly, which is designed to deliver a 1.5 MW, NB power of deuterium at 95 keV. Before the beam injection experiments, discharge, and beam extraction characteristics of the ion source were investigated. The ion source has good beam optics in a broad range of beam perveance. The optimum perveance is 1.1-1.3 μP, and the minimum beam divergence angle measured by the Doppler shift spectroscopy is 0.8°. The ion species ratio is D(+):D(2)(+):D(3)(+) = 75:20:5 at beam current density of 85 mA/cm(2). The arc efficiency is more than 1.0 A∕kW. In the 2010 KSTAR campaign, a deuterium NB power of 0.7-1.5 MW was successfully injected into the KSTAR plasma with a beam energy of 70-90 keV. L-H transitions were observed within a wide range of beam powers relative to a threshold value. The edge pedestal formation in the T(i) and T(e) profiles was verified through CES and electron cyclotron emission diagnostics. In every deuterium NB injection, a burst of D-D neutrons was recorded, and increases in the ion temperature and plasma stored energy were found.

  10. [Experience in scaling up the film coating process for theophylline sustained-release pellets in mass production].

    PubMed

    Grunenberg, P; Lorck, C; Jünger, H; Laicher, A

    1998-05-01

    The scale-up of the film coating process for the production of Bronchoretard pellets (theophylline, CAS 58-55-9) is an example for the successful setup of a modern production technology designed to meet the increasing GMP requirements while taking into consideration ecological and economical aspects. This technology provides a reduction in polymer losses on drying from approx. 20% to under 5% and a distinct improvement in the reproducibility of the in vitro dissolution profiles. Double batch sizes and higher spray rates allow for a substantially higher batch turnover. A production line installed exclusively for Bronchoretard pellets and specific process optimization measures resulted in considerably lower lag-times of the equipment.

  11. The Skylab barium plasma injection experiments. I - Convection observations

    NASA Technical Reports Server (NTRS)

    Wescott, E. M.; Stenbaek-Nielsen, H. C.; Davis, T. N.; Peek, H. M.

    1976-01-01

    Two barium-plasma injection experiments were carried out during magnetically active periods in conjunction with the Skylab 3 mission. The high-explosive shaped charges were launched near dawn on November 27 and December 4, 1973, UT. In both cases, the AE index was near 400 gammas, and extensive pulsating auroras covered the sky. The first experiment, Skylab Alpha, occurred in the waning phase of a 1000-gamma substorm, and the second, Skylab Beta, occurred in the expansive phase of an 800-gamma substorm. In both, the convection was generally magnetically eastward, with 100-km-level electric fields near 40 mV/m. However, in the Alpha experiment the observed orientation of the barium flux tube fit theoretical field lines having no parallel current, but the Beta flux-tube orientation indicated a substantial upward parallel sheet current.

  12. Modeling of Carbon Migration During JET Injection Experiments

    SciTech Connect

    Strachan, J. D.; Likonen, J.; Coad, P.; Rubel, M.; Widdowson, A.; Airila, M.; Andrew, P.; Brezinsek, S.; Corrigan, G.; Esser, H. G.; Jachmich, S.; Kallenbach, A.; Kirschner, A.; Kreter, A.; Matthews, G. F.; Philipps, V.; Pitts, R. A.; Spence, J.; Stamp, M.; Wiesen, S.

    2008-10-15

    JET has performed two dedicated carbon migration experiments on the final run day of separate campaigns (2001 and 2004) using {sup 13}CH{sub 4} methane injected into repeated discharges. The EDGE2D/NIMBUS code modelled the carbon migration in both experiments. This paper describes this modelling and identifies a number of important migration pathways: (1) deposition and erosion near the injection location, (2) migration through the main chamber SOL, (3) migration through the private flux region aided by E x B drifts, and (4) neutral migration originating near the strike points. In H-Mode, type I ELMs are calculated to influence the migration by enhancing erosion during the ELM peak and increasing the long-range migration immediately following the ELM. The erosion/re-deposition cycle along the outer target leads to a multistep migration of {sup 13}C towards the separatrix which is called 'walking'. This walking created carbon neutrals at the outer strike point and led to {sup 13}C deposition in the private flux region. Although several migration pathways have been identified, quantitative analyses are hindered by experimental uncertainty in divertor leakage, and the lack of measurements at locations such as gaps and shadowed regions.

  13. Enhanced Performance of Electrothermal Plasma Sources as Fusion Pellet Injection Drivers and Space Based Mini-Thrusters via Extension of a Flattop Discharge Current

    NASA Astrophysics Data System (ADS)

    Leigh Winfrey, A.; Abd Al-Halim, Mohamed A.; Saveliev, Alexei V.; Gilligan, John G.; Bourham, Mohamed A.

    2013-06-01

    Electrothermal plasma sources have been introduced as a method to propel frozen hydrogenic pellets for fueling of future magnetic fusion reactors. These sources are also useful as mini-thrusters in space shuttles, pre-injectors in hypervelocity launchers and igniters in electrothermal-chemical Guns. The source is a capillary discharge that generates the plasma from the ablation of a liner in an ablation-dominated regime, or from the flow of gas into the capillary in an ablation-free regime. Most electrothermal plasma sources uses pulse power delivery system with a pulse length in the range of 100 μs with FWHM of 50 μs. This research is a computational study on the effect of extending the top of the discharge current pulse to the range of 1,000 μs on the source exit parameter to achieve higher pressures and better exit velocities. Calculations using 0.4 cm diameter, 9.0 cm length Lexan polycarbonate capillary source, using ideal and nonideal plasma models, show that extended flattop pulses at fixed amplitude produce more ablated mass which scales linearly with increased pulse length, however, other plasma parameters remain almost constant. Results suggest that quasi-steady state operation of an electrothermal plasma source may provide constant exit pressure and velocity for pellet injectors for future magnetic fusion reactors deep fueling.

  14. The Tordo 1 polar cusp barium plasma injection experiment

    NASA Technical Reports Server (NTRS)

    Wescott, E. M.; Stenbaek-Nielsen, H. C.; Davis, T. N.; Jeffries, R. A.; Roach, W. H.

    1978-01-01

    In January 1975, two barium plasma injection experiments were carried out with rockets launched into the upper atmosphere where field lines from the dayside cusp region intersect the ionosphere. The Tordo 1 experiment took place near the beginning of a worldwide magnetic storm. It became a polar cap experiment almost immediately as convection perpendicular to the magnetic field moved the fluorescent plasma jet away from the cusp across the polar cap in an antisunward direction. Convection across the polar cap with an average velocity of more than 1 km/s was observed for nearly 40 min until the barium flux tubes encountered large electron fields associated with a poleward bulge of the auroral oval near Greenland. Prior to the encounter with the aurora near Greenland there is evidence of upward acceleration of the barium ions while they were in the polar cap. The three-dimensional observations of the plasma orientation and motion give an insight into convection from the cusp region across the polar cap, the orientation of the polar cap magnetic field lines out to several earth radii, the causes of polar cap magnetic perturbations, and parallel acceleration processes.

  15. Optical injection using colliding laser pulses: experiments at LBNL

    NASA Astrophysics Data System (ADS)

    Leemans, W. P.; Geddes, C. G. R.; Toth, C.; Faure, J.; van Tilborg, J.; Marcelis, B.; Esarey, E.; Schroeder, C. B.; Fubiani, G.; Shadwick, B. A.; Dugan, G.; Cary, J.; Giacone, R.

    2002-11-01

    Laser driven acceleration in plasmas has succeeded in producing electron beams containing multi-nC's of charge, with some fraction of the electrons having energies in excess of 10's of MeV's but 100 % energy spread. One of the current challenges is to produce electron beams with much reduced energy spread. We report on experimental progress in the laser triggered injection of electrons in a laser wakefield accelerator using the colliding pulse method (E. Esarey et al., Phys. Rev. Lett. 79, 2682 (1997).), (C.B. Schroeder et al., Phys. Rev. E 59, 6037 (1999).). The experiments use the l'OASIS multi-beam 10 Hz high power Ti:Al_2O3 laser system (W.P. Leemans et al., Phys. Plasmas 8, 2510 (2001).). In the present experiments, two counter propagating beams (30^rc angle) are focused onto a high density gas jet. Preliminary results indicate that electron beam properties are affected by the second beam. Details of the experiments will be shown as well as comparisons with simulations.

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

    SciTech Connect

    Meitner, S. J.; Baylor, L. R.; Combs, S. K.; Fehling, D. T.; McGill, J. M.; Duckworth, R. C.; McGinnis, W. D.; Rasmussen, D. A.

    2014-01-29

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

  17. A high-altitude barium radial injection experiment

    NASA Technical Reports Server (NTRS)

    Wescott, E. M.; Stenbaek-Nielsen, H. C.; Hallinan, T. J.; Deehr, C. S.; Romick, G. J.; Olson, J. V.; Roederer, J. G.; Sydora, R.

    1980-01-01

    A rocket launched from Poker Flat, Alaska, carried a new type of high-explosive barium shaped charge to 571 km, where detonation injected a thin disk of barium vapor with high velocity nearly perpendicular to the magnetic field. The TV images of the injection are spectacular, revealing three major regimes of expanding plasma which showed early instabilities in the neutral gas. The most unusual effect of the injection is a peculiar rayed barium-ion structure lying in the injection plane and centered on a 5 km 'black hole' surrounding the injection point. Preliminary electrostatic computer simulations show a similar rayed development.

  18. A Bichromator for High Time Resolution Measurements of Stark Broadened Pellet Ablation Light

    NASA Astrophysics Data System (ADS)

    Schmidt, G. L.; Baylor, L. R.; Fehling, D. T.; Jernigan, T. C.; Brooks, N. H.; Parks, P. B.

    2004-11-01

    Details of the pellet/plasma interaction are important for modeling of local pellet source rates and cross field transport of pellet mass. Understanding these processes is critical for projection of current fueling experiments to future devices such as ITER. Measurement of the Stark broadened deuterium emission lines provides the electron density and temperature of the pellet cloud for comparison with modeling details. Stark broadening measurements on JET for low field launch pellets at moderate time resolution indicate a slow variation in the cloud parameters. Observations of ablation light suggest changes in cloud parameters may occur on faster time scales. We report on the possible application of a multiple interference filter technique[1]to allow monitoring of cloud parameters at time resolution sufficient to study both the slow and rapid variations in cloud parameters. Application of the bichromator to line widths and temporal evolution typical of DIII-D pellet injection cases will be discussed.[1]McNeill,D.H.,RSI 73 (2002) 3193.

  19. Computer modeling of a three-dimensional steam injection experiment

    SciTech Connect

    Joshi, S.; Castanier, L.M.

    1993-08-01

    The experimental results and CT scans obtained during a steam-flooding experiment with the SUPRI 3-D steam injection laboratory model are compared with the results obtained from a numerical simulator for the same experiment. Simulation studies were carried out using the STARS (Steam and Additives Reservoir Simulator) compositional simulator. The saturation and temperature distributions obtained and heat-loss rates measured in the experimental model at different stages of steam-flooding were compared with those calculated from the numerical simulator. There is a fairly good agreement between the experimental results and the simulator output. However, the experimental scans show a greater degree of gravity override than that obtained with the simulator for the same heat-loss rates. Symmetric sides of the experimental 5-spot show asymmetric heat-loss rates contrary to theory and simulator results. Some utility programs have been written for extracting, processing and outputting the required grid data from the STARS simulator. These are general in nature and can be useful for other STARS users.

  20. New algorithm for computing the ablation of hydrogenic pellets in hot plasmas

    SciTech Connect

    Milora, S.L.

    1983-04-01

    A method is presented for calculating the evaporation rate of hydrogenic pellets immersed in an unmagnetized plasma with a suprathermal particle component of arbitrary distribution function. The computational procedure is based on hydrodynamic solutions for the expansion of the gaseous cloud, obtained in a previous treatment that considered the effects of thermal particles only. The appropriate heat source terms, derived from the stopping power of the gaseous shield, are worked out for energetic ions produced by neutral beam injection heating. The model predicts 27-cm penetration in a Poloidal Divertor Experiment (PDX) plasma, compared with experimentally measured values in the range of 29 to 32 cm. An application to the Tokamak Fusion Test Reactor (TFTR) gives an estimated 21-cm penetration for a 2.5-mm-diam tritium pellet injection at 2000 m/s into a 55-cm-bore plasma heated to a central electron temperature of 4 keV by 34 MW of neutral injection.

  1. 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.

  2. Experience of intravitreal injections in a tertiary Hospital in Oman

    PubMed Central

    Al-Hinai, Ahmed S.

    2015-01-01

    Aim: To find out statistical data regarding intravitreal injections in an outpatient department setup at a tertiary center in Oman. Design: Retrospective chart review. Methods: Data collection of patients who underwent intravitreal injections from November 2009 to May 2013 at Sultan Qaboos University Hospital. Results: Throughout a period of 42 months, a total of 711 intravitreal injections were performed. That included 214 patients (275 eyes). Around one-third of the eyes received two injections or more. The injected agents were bevacizumab (59.8%), ranibizumab (32.3%), triamcinolone (7.5%), and very few patients with endophthalmitis received intravitreal antibiotics and antifungal agents. The three most common indications for the injection therapy were diabetic macular edema (50.9%), choroidal neovascularization (24.3%), and retinal vein occlusive diseases (11.5%). Serious adverse events were rare, and they occurred as ocular (0.9% per patient) and systemic (3.3% per patient). There were 42 eyes received intravitreal triamcinolone, and 24% of them developed intraocular hypertension that required only medical treatment. Conclusion: Different intravitreal agents are currently used to treat many ocular diseases. Currently, therapy with intravitreal agents is very popular, and it carries a promising outcome with more efficiency and safety. PMID:26903722

  3. Injection safety for immunisation--Andhra Pradesh experience.

    PubMed

    Kaipilyawar, Satish B; Rao, R Gopal Krishna

    2005-04-01

    Injection safety is one component of a major immunisation project being implemented in partnership with Government of Andhra Pradesh and PATH, an international NGO. Prior to the project wrong and dangerous injection giving practices were present among the staff which needed immediate attention. It was decided to introduce auto disable syringes along with safety boxes with high quality training to staff and make all these available to all districts along with hepatitis B introduction in the routine immunisation. The State of Andhra Pradesh became the first to implement 'bundling' concept in the immunisation project. Implementation was planned to be done in a phased manner to cover all the 23 districts over a five-year period. For routine immunisation sessions, smaller locally produced boxes may be more acceptable. The Government of India made a decision on 21st July, 2004 on implementing injection safety. Injection safety and proper disposal of used needles and syringes can be successfully advocated if medical associations, paediatric associations, key governmental bodies and international agencies come together. PATH established a group and holds the secretariat for the India injection safety coalition on similar basis as the Safe Injection Global Network of WHO (SIGN). Description of AP system for safe disposal of needles and syringes using manual needle-cutters and plastics recycling has been depicted in this article.

  4. Pellet inspection apparatus

    DOEpatents

    Wilks, Robert S.; Taleff, Alexander; Sturges, Jr., Robert H.

    1982-01-01

    Apparatus for inspecting nuclear fuel pellets in a sealed container for diameter, flaws, length and weight. The apparatus includes, in an array, a pellet pick-up station, four pellet inspection stations and a pellet sorting station. The pellets are delivered one at a time to the pick-up station by a vibrating bowl through a vibrating linear conveyor. Grippers each associated with a successive pair of the stations are reciprocable together to pick up a pellet at the upstream station of each pair and to deposit the pellet at the corresponding downstream station. The gripper jaws are opened selectively depending on the state of the pellets at the stations and the particular cycle in which the apparatus is operating. Inspection for diameter, flaws and length is effected in each case by a laser beam projected on the pellets by a precise optical system while each pellet is rotated by rollers. Each laser and its optical system are mounted in a container which is free standing on a precise surface and is provided with locating buttons which engage locating holes in the surface so that each laser and its optical system is precisely set. The roller stands are likewise free standing and are similarly precisely positioned. The diameter optical system projects a thin beam of light which scans across the top of each pellet and is projected on a diode array. The fl GOVERNMENT CONTRACT CLAUSE The invention herein described was made in the course of or under a contract or subcontract thereunder with the Department of Energy bearing No. EY-67-14-C-2170.

  5. Carbonaceous pellets and method of pelletizing

    SciTech Connect

    Dondelewski, M.A.

    1982-11-02

    A method is claimed for pelletizing carbonaceous materials including bonding coal fines and lignite coal with a polymeric hydrocarbon binder having reactive sites thereon. For example, with tall oil pitch and the like, in the case of coal, the binder is applied by slurrying the fine coal with the pitch. In the case of lignite, the binder is directly applied to the pulverized material. By action of rolling and tumbling, for example, large agglomerates are formed. With drying and heating, strong water-resistant pellets are formed which have the extremely desirable property of being easily repulverized.

  6. Reciprocating pellet press

    DOEpatents

    Jones, Charles W.

    1981-04-07

    A machine for pressing loose powder into pellets using a series of reciprocating motions has an interchangeable punch and die as its only accurately machines parts. The machine reciprocates horizontally between powder receiving and pressing positions. It reciprocates vertically to press, strip and release a pellet.

  7. LABORATORY MICROCOSM EXPERIMENTS OF OXIDATION PROCESSES AFTER STEAM INJECTION

    EPA Science Inventory

    Aggressive thermal methods such as steam injection or resistive heating are known to be effective for the recovery of many types of volatile and semivolatile compounds. It has been suggested that oxidation or other chemical reactions that occur at remediation temperatures can ai...

  8. Features of spontaneous and pellet-induced ELMs on the HL-2A tokamak

    NASA Astrophysics Data System (ADS)

    Huang, Y.; Liu, C. H.; Nie, L.; Feng, Z.; Ji, X. Q.; Yao, K.; Zhu, G. L.; Liu, Yi; Cui, Z. Y.; Yan, L. W.; Wang, Q. M.; Yang, Q. W.; Ding, X. T.; Dong, J. Q.; Duan, X. R.

    2012-11-01

    The pellet pacing ELM mitigation concept is being tested in some tokamaks such as ASDEX Upgrade, DIII-D and JET. By increasing the ELM frequency, the ELM size can be reduced and eventually suppressed to meet the lifetime requirements on ITER target plates. In the HL-2A tokamak, ELMy H-mode operation is routinely performed and small type-III ELMs with a high repetition rate and some type-I (or possibly large type-III) ELM events are observed. Large ELMs are often preceded by strong coherent magnetic oscillations, and produce obvious perturbations on plasma current Ip, electron density \\bar {n}_{edge} at the edge, stored energy WE, etc. The coherent magnetic oscillations before an ELM crash or during the ELM are measured by toroidal and poloidal Mirnov coils and analysed by the wavelet technique to study the spectral characteristics of the short time ELM events. Pellet injection experiments are performed in type-III ELMy H-mode plasmas and ELM-free H-mode plasmas to study the physics of pellet triggering ELM. The analyses of pellet-induced ELMs and spontaneous ELMs are presented. Because the pellet size is relatively large, it induces magnetic oscillations lasting longer than that of a natural ELM.

  9. Lignite pellets and methods of agglomerating or pelletizing

    DOEpatents

    Baker, Albert F.; Blaustein, Eric W.; Deurbrouck, Albert W.; Garvin, John P.; McKeever, Robert E.

    1981-01-01

    The specification discloses lignite pellets which are relatively hard, dust resistant, of generally uniform size and free from spontaneous ignition and general degradation. Also disclosed are methods for making such pellets which involve crushing as mined lignite, mixing said lignite with a binder such as asphalt, forming the lignite binder mixture into pellets, and drying the pellets.

  10. Imaging polychromator for density measurements of polystyrene pellet cloud on the Large Helical Device.

    PubMed

    Sharov, I A; Sergeev, V Yu; Miroshnikov, I V; Tamura, N; Kuteev, B V; Sudo, S

    2015-04-01

    Experimental data on spatial distributions of a pellet cloud electron density are necessary for the development of many applications of pellet injection, namely, plasma fuelling, discharge control, and plasma diagnostics. An improved approach of electron density measurements inside the cloud of a polystyrene pellet ablating in hot plasma of the large helical device is described. Density values of (1-30) × 10(16) cm(-3) depending on the background plasma parameters and distance from the solid pellet were measured.

  11. Hydrothermal injection experiments at the Raft River KGRA, Idaho

    SciTech Connect

    Downs, W.F.; McAtee, R.E.; Capuano, R.M.; Sill, W.

    1982-12-14

    The optimal development and management of a geothermal resource requires a knowledge of the hydrological characteristics of the reservoir. Reservoir engineering analysis techniques for permeable aquifers have been undergoing development for several decades but little attention has been paid to fracture-dominated systems. A program to test the ability of Huff-Puff tests to help characterize a fracture-dominated reservoir is presented. Several series of these injection (Huff)-backflow (Puff) tests were conducted at the Raft River KGRA in Southern Idaho. These test series are described and preliminary results and interpretations are discussed.

  12. Mobile Biomass Pelletizing System

    SciTech Connect

    Thomas Mason

    2009-04-16

    This grant project examines multiple aspects of the pelletizing process to determine the feasibility of pelletizing biomass using a mobile form factor system. These aspects are: the automatic adjustment of the die height in a rotary-style pellet mill, the construction of the die head to allow the use of ceramic materials for extreme wear, integrating a heat exchanger network into the entire process from drying to cooling, the use of superheated steam for adjusting the moisture content to optimum, the economics of using diesel power to operate the system; a break-even analysis of estimated fixed operating costs vs. tons per hour capacity. Initial development work has created a viable mechanical model. The overall analysis of this model suggests that pelletizing can be economically done using a mobile platform.

  13. Radation shielding pellets

    DOEpatents

    Coomes, Edmund P.; Luksic, Andrzej T.

    1988-12-06

    Radiation pellets having an outer shell, preferably, of Mo, W or depleted U nd an inner filling of lithium hydride wherein the outer shell material has a greater melting point than does the inner filling material.

  14. Pneumatic Pellet-Transporting System

    NASA Technical Reports Server (NTRS)

    Wood, George; Pugsley, Robert A.

    1992-01-01

    Pneumatic system transports food pellets to confined animals. Flow of air into venturi assembly entrains round pellets, drawing them from reservoir into venturi for transport by airflow. Pneumatic pellet-transporting system includes venturi assembly, which creates flow of air that draws pellets into system.

  15. A discrete-choice experiment to determine patient preferences for injectable multiple sclerosis treatments in Germany

    PubMed Central

    Poulos, Christine; Kinter, Elizabeth; Yang, Jui-Chen; Bridges, John F. P.; Posner, Joshua; Gleißner, Erika; Mühlbacher, Axel; Kieseier, Bernd

    2016-01-01

    Objectives: The aim of this study was to assess the relative importance of features of a hypothetical injectable disease-modifying treatment for patients with multiple sclerosis using a discrete-choice experiment. Methods: German residents at least 18 years of age with a self-reported physician diagnosis of multiple sclerosis completed a 25–30 minute online discrete-choice experiment. Patients were asked to choose one of two hypothetical injectable treatments for multiple sclerosis, defined by different levels of six attributes (disability progression, the number of relapses in the next 4 years, injection time, frequency of injections, presence of flu-like symptoms, and presence of injection-site reactions). The data were analyzed using a random-parameters logit model. Results: Of 202 adults who completed the survey, results from 189 were used in the analysis. Approximately 50% of all patients reported a diagnosis of relapsing–remitting multiple sclerosis, and 31% reported secondary progressive multiple sclerosis. Approximately 71% of patients had current or prior experience with injectable multiple sclerosis medication. Approximately 53% had experienced flu-like symptoms caused by their medication, and 47% had experienced mild injection-site reactions. At least one significant difference was seen between levels in all attributes, except injection time. The greatest change in relative importance between levels of an attribute was years until symptoms get worse from 1 to 4 years. The magnitude of this difference was about twice that of relapses in the next 4 years, frequency of injections, and flu-like symptoms. Conclusions: Most attributes examined in this experiment had an influence on patient preference. Patients placed a significant value on improvements in the frequency of dosing and disability progression. Results suggest that changes in injection frequency can be as important as changes in efficacy and safety attributes. Understanding which attributes of

  16. Tritium proof-of-principle pellet injector: Phase 2

    NASA Astrophysics Data System (ADS)

    Fisher, P. W.; Gouge, M. J.

    1995-03-01

    As part of the International Thermonuclear Engineering Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. This repeating, single-stage, pneumatic injector, called the Tritium-Proof-of-Principle Phase-2 (TPOP-2) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude hydrogenic pellets sized for the ITER device. The TPOP-II program has the following development goals: evaluate the feasibility of extruding tritium and DT mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and DT extrusions; integrate, test and evaluate the extruder in a repeating, single-stage light gas gun sized for the ITER application (pellet diameter approximately 7-8 mm); evaluate options for recycling propellant and extruder exhaust gas; evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory requiring secondary and room containment systems. In initial tests with deuterium feed at ORNL, up to thirteen pellets have been extruded at rates up to 1 Hz and accelerated to speeds of order 1.0-1.1 km/s using hydrogen propellant gas at a supply pressure of 65 bar. The pellets are typically 7.4 mm in diameter and up to 11 mm in length and are the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 11% density perturbation to ITER. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first wall tritium inventories by a process called isotopic fueling where tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge.

  17. Physics of forced magnetic reconnection in coaxial helicity injection experiments in National Spherical Torus Experiment

    SciTech Connect

    Ebrahimi, F.; Bhattacharjee, A.; Raman, R.; Hooper, E. B.; Sovinec, C. R.

    2014-05-15

    We numerically examine the physics of fast flux closure in transient coaxial helicity injection (CHI) experiments in National Spherical Torus Experiment (NSTX). By performing resistive Magnetohydrodynamics (MHD) simulations with poloidal injector coil currents held constant in time, we find that closed flux surfaces are formed through forced magnetic reconnection. Through a local Sweet-Parker type reconnection with an elongated current sheet in the injector region, closed flux surfaces expand in the NSTX global domain. Simulations demonstrate outflows approaching poloidally Alfvénic flows and reconnection times consistent with the Sweet-Parker model. Critical requirements for magnetic reconnection and flux closure are studied in detail. These primary effects, which are magnetic diffusivity, injector flux, injector flux footprint width, and rate of injector voltage reduction, are simulated for transient CHI experiments. The relevant time scales for effective reconnection are τ{sub V}<τ{sub rec}≈τ{sub A}√(S)(1+Pm){sup 1/4}<τ{sub R}, where τ{sub V} is the time for the injector voltage reduction, τ{sub A} is the poloidal Alfvén transit time, τ{sub R} is the global resistive diffusion time, and Pm and S are Prandtl and Lundquist numbers.

  18. Deportation Experiences of Women Who Inject Drugs in Tijuana, Mexico

    PubMed Central

    Robertson, Angela M.; Lozada, Remedios; Vera, Alicia; Palinkas, Lawrence A.; Burgos, José Luis; Magis-Rodriguez, Carlos; Rangel, Gudelia; Ojeda, Victoria D.

    2013-01-01

    Deportation from the United States for drug offenses is common, yet the consequences of deportation for women drug users are poorly documented. In 2008, in Tijuana, Mexico, we conducted an exploratory qualitative study of migration, deportation, and drug abuse by interviewing 12 Mexican injection-drug-using women reporting U.S. deportation. Women reported heavy drug use before and after deportation, but greater financial instability and physical danger following deportation than when in the United States. We identified an unmet need for health and social services among deported drug-using women, including HIV prevention, drug treatment, physical and mental health services, and vocational training. Binational coordination is needed to help deported women resettle in Mexico. PMID:21917563

  19. Deportation experiences of women who inject drugs in Tijuana, Mexico.

    PubMed

    Robertson, Angela M; Lozada, Remedios; Vera, Alicia; Palinkas, Lawrence A; Burgos, José Luis; Magis-Rodriguez, Carlos; Rangel, Gudelia; Ojeda, Victoria D

    2012-04-01

    Deportation from the United States for drug offenses is common, yet the consequences of deportation for women drug users are poorly documented. In 2008, in Tijuana, Mexico, we conducted an exploratory qualitative study of migration, deportation, and drug abuse by interviewing 12 Mexican injection-drug-using women reporting U.S. deportation. Women reported heavy drug use before and after deportation, but greater financial instability and physical danger following deportation than when in the United States. We identified an unmet need for health and social services among deported drug-using women, including HIV prevention, drug treatment, physical and mental health services, and vocational training. Binational coordination is needed to help deported women resettle in Mexico.

  20. A compact lithium pellet injector for tokamak pedestal studies in ASDEX Upgrade

    NASA Astrophysics Data System (ADS)

    Arredondo Parra, R.; Moreno Quicios, R.; Ploeckl, B.; Birkenmeier, G.; Herrmann, A.; Kocsis, G.; Laggner, F. M.; Lang, P. T.; Lunt, T.; Macian-Juan, R.; Rohde, V.; Sellmair, G.; Szepesi, T.; Wolfrum, E.; Zeidner, W.; Neu, R.

    2016-02-01

    Experiments have been performed at ASDEX Upgrade, aiming to investigate the impact of lithium in an all-metal-wall tokamak and attempting to enhance the pedestal operational space. For this purpose, a lithium pellet injector has been developed, capable of injecting pellets carrying a particle content ranging from 1.82 × 1019 atoms (0.21 mg) to 1.64 × 1020 atoms (1.89 mg). The maximum repetition rate is about 2 Hz. Free flight launch from the torus outboard side without a guiding tube was realized. In such a configuration, angular dispersion and speed scatter are low, and a transfer efficiency exceeding 90% was achieved in the test bed. Pellets are accelerated in a gas gun; hence special care was taken to avoid deleterious effects by the propellant gas pulse. Therefore, the main plasma gas species was applied as propellant gas, leading to speeds ranging from 420 m/s to 700 m/s. In order to minimize the residual amount of gas to be introduced into the plasma vessel, a large expansion volume equipped with a cryopump was added into the flight path. In view of the experiments, an optimal propellant gas pressure of 50 bars was chosen for operation, since at this pressure maximum efficiency and low propellant gas flux coincide. This led to pellet speeds of 585 m/s ± 32 m/s. Lithium injection has been achieved at ASDEX Upgrade, showing deep pellet penetration into the plasma, though pedestal broadening has not been observed yet.

  1. A compact lithium pellet injector for tokamak pedestal studies in ASDEX Upgrade.

    PubMed

    Arredondo Parra, R; Moreno Quicios, R; Ploeckl, B; Birkenmeier, G; Herrmann, A; Kocsis, G; Laggner, F M; Lang, P T; Lunt, T; Macian-Juan, R; Rohde, V; Sellmair, G; Szepesi, T; Wolfrum, E; Zeidner, W; Neu, R

    2016-02-01

    Experiments have been performed at ASDEX Upgrade, aiming to investigate the impact of lithium in an all-metal-wall tokamak and attempting to enhance the pedestal operational space. For this purpose, a lithium pellet injector has been developed, capable of injecting pellets carrying a particle content ranging from 1.82 × 10(19) atoms (0.21 mg) to 1.64 × 10(20) atoms (1.89 mg). The maximum repetition rate is about 2 Hz. Free flight launch from the torus outboard side without a guiding tube was realized. In such a configuration, angular dispersion and speed scatter are low, and a transfer efficiency exceeding 90% was achieved in the test bed. Pellets are accelerated in a gas gun; hence special care was taken to avoid deleterious effects by the propellant gas pulse. Therefore, the main plasma gas species was applied as propellant gas, leading to speeds ranging from 420 m/s to 700 m/s. In order to minimize the residual amount of gas to be introduced into the plasma vessel, a large expansion volume equipped with a cryopump was added into the flight path. In view of the experiments, an optimal propellant gas pressure of 50 bars was chosen for operation, since at this pressure maximum efficiency and low propellant gas flux coincide. This led to pellet speeds of 585 m/s ± 32 m/s. Lithium injection has been achieved at ASDEX Upgrade, showing deep pellet penetration into the plasma, though pedestal broadening has not been observed yet.

  2. Competing atomic processes in Ba and Sr injection critical velocity experiments

    NASA Technical Reports Server (NTRS)

    Newell, P. T.; Torbert, R. B.

    1985-01-01

    The critical ionization velocity effect requires a superthermal electron population to ionize through collisional impact. Such superthermal electrons can however lose energy to competing atomic processes, as well as to ionization, thus limiting the efficiency of the effect. Considering Ba and Sr magnetospheric injection experiments designed to test the CIV theory, it is found that in both cases roughly 60 percent of the superthermal electron energy is lost on exciting line radiation. Moreover, energy loss to background neutral oxygen places a strict limit on the injected cloud densities for which critical velocity effects are possible; a finding which explains the consistently negative results in radial injection experiments.

  3. Current drive experiments in the Helicity Injected Torus - II

    NASA Astrophysics Data System (ADS)

    Hamp, W. T.; Redd, A. J.; Jarboe, T. R.; Nelson, B. A.; O'Neill, R. G.; Raman, R.; Sieck, P. E.; Smith, R. J.; Mueller, D.

    2006-10-01

    The HIT-II spherical torus (ST) device has demonstrated four toroidal plasma current drive configurations to form and sustain a tokamak: 1) inductive (ohmic) current drive, 2) coaxial helicity injection (CHI) current drive, 3) CHI initiated plasmas with ohmic sustainment (CHI+OH), and 4) ohmically initiated plasmas with CHI edge current drive (OH+ECD). CHI discharges with a sufficiently high ratio of injector current to toroidal field current form a closed flux core, and amplify the injector poloidal flux through magnetic reconnection. CHI+OH plasmas are more robust than unassisted ohmic discharges, with a wider operating space and more efficient use of the transformer Volt-seconds. Finally, edge CHI can enhance the plasma current of an ohmic discharge without significantly degrading the quality of the discharge. Results will be presented for each HIT-II operating regime, including empirical performance scalings, applicable parametric operating spaces, and requirements to produce these discharges. Thomson scattering measurements and EFIT simulations are used to evaluate confinement in several representative plasmas. Finally, we outline extensions to the HIT-II CHI studies that could be performed with NSTX, SUNIST, or other ST devices.

  4. Active experiments in space in conjunction with Skylab. [barium plasma injection experiment and magnetic storm of March 7, 1972

    NASA Technical Reports Server (NTRS)

    Wescott, E. M.

    1974-01-01

    Two papers are presented which relate to the Skylab barium shaped charge experiments. The first describes the L=6.6 OOSIK barium plasma injection experiment and magnetic storm of March 7, 1972. Rocket payload, instrumentation, data reduction methods, geophysical environment at the time of the experiment, and results are given. The second paper presents the observation of an auroral Birkeland current which developed from the distortion of a barium plasma jet during the above experiment.

  5. Permeability of wood pellets in the presence of fines.

    PubMed

    Yazdanpanah, F; Sokhansanj, S; Lau, A K; Lim, C J; Bi, X; Melin, S; Afzal, M

    2010-07-01

    Broken pellets and fines are produced when pellets are handled. The resistance to air flow was measured for clean pellets and for pellets mixed with 1-20% broken pellets (fines). A pellet diameter was 6mm. The lengths ranged from 6 to 12 mm. Clean pellets were defined as particles that remained on a 4mm screen. A typical sieve analysis showed 30% of the mass of particles that passed through the 4mm screen was smaller than 1mm. The airflow rates used in the experiment ranged from 0.004 to 0.357 ms(-1). The corresponding pressure drop ranged from 1.9 to 271 Pam(-1) for clean pellets, from 4.8 to 1100 Pam(-1) for 10% fines content, and from 7.9 to 1800 Pam(-1) for 20% fines content. Coefficients of Hukill and Ives' equation were estimated for clean pellets and a multiplier was defined to calculate pressure drop for pellets mixed with fines.

  6. Transport and MHD simulations of intrinsic and pellet induced ELMs

    NASA Astrophysics Data System (ADS)

    Kim, Ki Min; Na, Yong-Su; Yi, Sumin; Kim, Hyunseok; Kim, Jin Yong

    2010-11-01

    Verification of ELM mechanism and demonstration of ELM control are important issues in current fusion researches targeting ITER and DEMO. This work investigates the physics and operational characteristics of intrinsic and pellet induced ELMs throughout transport simulations using 1.5 D transport codes (C1.5/ASTRA) and MHD simulations using M3D code. Transport simulations are focused on prediction of the global parameters such as ELM energy loss in the type-I ELMy H-mode discharges with and without pellet pace making to examine an applicability of pellet injection for ELM mitigation in KSTAR and ITER. On the other hand, MHD simulations are conducted to explore the physics of intrinsic and pellet induced ELMs by applying the artificial free energy sources of velocity stream and density perturbations on the marginally stable equilibrium, respectively. Similarities and differences of triggering phenomena between intrinsic and pellet induced ELMs are discussed from the MHD approach.

  7. Production of zinc pellets

    SciTech Connect

    Cooper, J.F.

    1996-11-26

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries. 6 figs.

  8. Production of zinc pellets

    SciTech Connect

    Cooper, John F.

    1996-01-01

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries.

  9. Injecting learning experience into geoethics for human and natural sustainability

    NASA Astrophysics Data System (ADS)

    Crookall, David

    2016-04-01

    Our early life experience has a strong influence on our actions in later life. Humans today are just starting to re-learn, collectively, how to treat Earth with the respect that it deserves and that is needed for our offspring to inherit a decent home. However, we still have a long way to go to instill in people at large the ethics, knowledge and skills necessary to ensure a healthy journey for humanity on spaceship. The experience of early upbringing, of schooling and of everyday life is probably the only path strong enough to develop in people a strong desire for ethical behaviour towards their environment. The problem is that the measures taken today to ensure the development of ethical behaviours in the population at large are woefully inadequate. At best, western school programmes contain a few lessons devoted to the environment, and even then they usually just pay lip service to the basics of the environment; they rarely aim to instill skills and knowledge in order to understand and care deeply for the environment. My presentation will suggest some practical ways to help communities build ethical frameworks and strategies to guide and generate tools, methods and activities that guide young people (pupils, students, scholars, researchers) to toward more ethical behaviours regarding their environment and their communities. Examples might include: - Developing geoethical dimensions of internships, in all areas; - Designing, testing and running simulation/games+debriefing providing a rich affective-cognitive context for grappling with geoethical problems- eg, FISH BANKS, KEEP COOL. - Pressuring governments to make geoethics, environmental care and climate change understanding central components of (almost) all educational programmes (in, eg, history, language, business, law, medicine, etc). - Subsidizing environmental-care summer schools for families and teachers at all levels. - Etc. One of my actions is founding a academic journal in the area, maybe with the

  10. Settling behaviour of pellet flocs in pelleting flocculation process: analysis through operational conditions.

    PubMed

    Gang, Zhang; Ting-lin, Huang; Chi, Tan; Zhan-peng, Li; Wen-jie, He; Hong-da, Han; Chen, Li

    2010-01-01

    Pellet flocs' settling velocity is an important parameter in the pelleting flocculation blanket (PFB) process, hence, it is necessary to investigate flocs' settling behaviour to achieve the optimum operation parameters of the process. To investigate the settling behaviour of pellets under different operational conditions, a dynamic experiment was carried out to concentrate ferric flocs sludge by pelleting flocculation blanket (PFB) process with the scale of 0.5-1.2 m3/h. Under different operating conditions such as raw water concentration, polyacrylamide (PAM) dosage, up-flow rate, and agitation speed, pellet particles were sampled from different locations of the blanket in various operating stages to analyze pellet size, setting velocity, and porosity. Experimental results indicated that, when the PAM dosage increased from 0.59 mg/L to 1.18 mg/L, pellets size would flocculated from 2.25 mm to 3.52 mm with the settling velocity accelerated from 3.28 mm/s to 7.37 mm/s, while under the same up-flow rate, agitation intensity and PAM dosage, accompany with the raw water concentration increased from 216 mg/L to 840 mg/L, pellets settling velocity would improved from 6.03 mm/s to 13.6 mm/s. Under the experimental condition, along with the up-flow rate increased from 13.3 m/h to 40 m/h, pellets settling velocity would decreased from 4.39 mm/s to 3.42 mm/s due to its lower density.

  11. External-injection Experiment at SPARC_LAB

    NASA Astrophysics Data System (ADS)

    Rossi, A. R.; Bacci, A.; Belleveglia, M.; Chiadroni, E.; Cianchi, A.; Di Pirro, G.; Ferrario, M.; Gallo, A.; Gatti, G.; Maroli, C.; Mostacci, A.; Petrillo, V.; Serafini, L.; Tomassini, P.; Vaccarezza, C.

    At the SPARC_LAB facility of INFN-LNF we are installing two transport lines for ultra-short electron bunches and an ultra- intense laser pulses, generated by the SPARC photo-injector and by the FLAME laser in a synchronized fashion at the tens of f s level, to co-propagate inside a hydrogen filled glass capillary, in order to perform acceleration of the electron bunch by a plasma wave driven by the laser pulse. The main aim of this experiment is to demonstrate that a high brightness electron beam can be accelerated by a plasma wave without any significant degradation of its quality. Motivations of the technical choices made and expected performances are reported.

  12. An Ion-Selective Electrode/Flow-Injection Analysis Experiment: Determination of Potassium in Serum.

    ERIC Educational Resources Information Center

    Meyerhoff, Mark E.; Kovach, Paul M.

    1983-01-01

    Describes a low-cost, senior-level, instrumental analysis experiment in which a home-made potassium tubular flow-through electrode is constructed and incorporated into a flow injection analysis system (FIA). Also describes experiments for evaluating the electrode's response properties, examining basic FIA concepts, and determining potassium in…

  13. An enhancement of plasma density by neutral gas injection observed in SEPAC Spacelab-1 experiment

    NASA Technical Reports Server (NTRS)

    Sasaki, S.; Kawashima, N.; Kuriki, K.; Yanagisawa, M.; Obayashi, T.; Kubota, S.; Roberts, W. T.; Reasoner, D. L.; Taylor, W. W. L.; Williamson, P. R.

    1985-01-01

    An enhancement of plasma density observed during a neutral gas injection in Space Experiments with Particle Accelerators by the Space Shuttle/Spacelab-1 is presented. When a plume of nitrogen gas was injected from the orbiter into space, a large amount of plasma was detected by an onboard plasma probe. The observed density often increased beyond the background plasma density and was strongly dependent on the attitude of the orbiter with respect to the velocity vector. This effect has been explained by a collisional interaction between the injected gas molecules and the ionospheric ions relatively drifting at the orbital speed.

  14. Fast Imaging of Intact and Shattered Cryogenic Neon Pellets

    SciTech Connect

    Wang, Zhehui; Combs, Stephen Kirk; Baylor, Larry R; Foust, Charles R; Lyttle, Mark S; Meitner, Steven J; Rasmussen, David A

    2014-01-01

    Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100- m- and sub- s-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of m to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.

  15. Fast imaging of intact and shattered cryogenic neon pellets

    SciTech Connect

    Wang, Zhehui; Combs, S. K.; Baylor, L. R.; Foust, C. R.; Lyttle, M. S.; Meitner, S. J.; Rasmussen, D. A.

    2014-11-15

    Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100-µm- and sub-µs-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of µm to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.

  16. Fast imaging of intact and shattered cryogenic neon pellets.

    PubMed

    Wang, Zhehui; Combs, S K; Baylor, L R; Foust, C R; Lyttle, M S; Meitner, S J; Rasmussen, D A

    2014-11-01

    Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100-µm- and sub-µs-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of µm to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.

  17. Owl Pellet Paleontology

    ERIC Educational Resources Information Center

    McAlpine, Lisa K.

    2013-01-01

    In this activity for the beginning of a high school Biology 1 evolution unit, students are challenged to reconstruct organisms found in an owl pellet as a model for fossil reconstruction. They work in groups to develop hypotheses about what animal they have found, what environment it inhabited, and what niche it filled. At the end of the activity,…

  18. From serpentinization to carbonation: New insights from a CO2 injection experiment

    NASA Astrophysics Data System (ADS)

    Klein, Frieder; McCollom, Thomas M.

    2013-10-01

    We injected a CO2-rich hydrous fluid of seawater chlorinity into an ongoing, mildly reducing (H2(aq)≈3 mmol/kg) serpentinization experiment at 230 °C and 35 MPa to examine the changes in fluid chemistry and mineralogy during mineral carbonation. The chemistry of 11 fluid samples was measured, speciated, and compared with MgO-SiO2-H2O-CO2 (MSHC) phase equilibria to approximate the reaction pathway from serpentinization to carbonation. Although the overall system was in apparent disequilibrium, the speciated activities of dissolved silica (aSiO2(aq)) and carbon dioxide (aCO2(aq)) evolved roughly along MSHC equilibrium phase boundaries, indicative of 4 distinct mineral assemblages over time: (1) serpentine-brucite (± magnesite) before the injection, to (2) serpentine-talc-magnesite 2 h after the injection, to (3) quartz-magnesite (48 h after injection), and (4) metastable olivine-magnesite (623 h after injection) until the experiment was terminated. Inspection of the solid reaction products revealed the presence of serpentine, magnesite, minor talc, and magnetite, in addition to relict olivine. Although quartz was saturated over a short segment of the experiment, it was not found in the solid reaction products. A marked and rapid change in fluid chemistry suggests that serpentinization ceased and precipitation of magnesite initiated immediately after the injection. A sharp decrease in pH after the injection promoted the dissolution of brucite and olivine, which liberated SiO2(aq) and dissolved Mg. Dissolved Mg was efficiently removed from the solution via magnesite precipitation, whereas the formation of talc was relatively sluggish. This process accounts for an increase in aSiO2(aq) to quartz saturation shortly after the injection of the CO2-rich fluid. Molecular dihydrogen (H2(aq)) was generated during serpentinization of olivine by oxidation of ferrous iron before the injection; however, no additional H2(aq) was generated after the injection. Speciation

  19. Formation of particulate matter monitoring during combustion of wood pellete with additives

    NASA Astrophysics Data System (ADS)

    Palacka, Matej; Holubčík, Michal; Vician, Peter; Jandačka, Jozef

    2016-06-01

    Application additives into the material for the production of wood pellets achieve an improvement in some properties such as pellets ash flow temperature and abrasion resistance. Additives their properties influence the course of combustion, and have an impact on the results of issuance. The experiment were selected additives corn starch and dolomite. Wood pellets were produced in the pelleting press and pelletizing with the additives. Selected samples were tested for the production of particulate matter (PM) during their direct burn. The paper analyzing a process of producing wood pellets and his effect on the final properties.

  20. Impacts of Humic Injection Experiments on the South Oyster Field Research Site

    SciTech Connect

    John F. McCarthy

    2004-04-27

    A closure plan for the South Oyster Focus Area (SOFA) is being implemented to assess the impacts of a series of experimental injections of microorganisms, tracers and chemical amendments on the chemical and physical properties of the aquifer. The proposed research addresses environmental monitoring of humic substances injected into the aquifer, as described in the Site Closure Plan for the South Oyster Field Research Site. The goal of the research is to demonstrate that the dissolved organic matter (DOM) in the groundwater at and downgradient from the injection site has returned to a pre-injection �baseline� conditions with respect to either the concentration or chemical composition of the DOM. For clarity, the humic solution injected during the experiment will be referred to as �humic injectate.� The term �DOM� will refer to the organic material recovered in the groundwater, which includes the autochthonous groundwater DOM as well as any of the humic injectate remaining in the groundwater. Specific objectives include: � Estimate the amount of humic material remaining in the aquifer at the completion of the push-pull experiment and the potential for environmental impacts due to release of humics retained on the sediments. � Monitor the DOM concentrations in groundwater over time at the injection well and at sampling locations within the potential downgradient plume of the injected tracers. � Evaluate the chemical composition of the DOM to determine whether the injection experiment had an impact of the chemical properties of the aquifer. The product of this research will be a contribution to the Site Closure Report documenting the impact of the humic experiments on the aquifer. Return of the aquifer to a �baseline� conditions will be achieved if the DOM concentrations in the groundwater are determined over the course of the research to have decreased to the pre-injection level, or if the chemical properties of

  1. Three-dimensional spiral injection scheme for the g-2/EDM experiment at J-PARC

    NASA Astrophysics Data System (ADS)

    Iinuma, Hiromi; Nakayama, Hisayoshi; Oide, Katsunobu; Sasaki, Ken-ichi; Saito, Naohito; Mibe, Tsutomu; Abe, Mitsushi

    2016-10-01

    A newly developed three-dimensional spiral injection scheme for beam insertion into a solenoidal storage ring is reported. A new planned muon g-2/EDM experiment at J-PARC aims to measure g - 2 to a factor of 5 better statistical precision and a factor of 100 better sensitivity for the electric dipole moment (EDM) measurement compared to previous experiments. The J-PARC experiment will use a 3-T MRI solenoid magnet as the muon storage ring with a 0.66 m diameter to achieve a 1-ppm level of local uniformity. The previous g - 2 injection scheme is not applicable for beam injection into a small ring. The new scheme provides a smooth injection utilizing a radial solenoidal fringe field, without causing an error field in the storage volume. The expected storage efficiency is 80% and over, which is to be compared to 3.5% for the previous g - 2 experiment. In addition, the ability to control the storage plane is important for the EDM measurement. In this paper, we introduce the conceptual design and required beam parameters in terms of Twiss functions and the expected injection efficiency.

  2. Results and analysis of the TMX electron-beam injection experiments

    SciTech Connect

    Poulsen, P.; Grubb, D.P.

    1980-08-01

    Electron beams (e-beams) were injected into the Tandem Mirror Experiment (TMX) plasma in order to investigate the effect on the ion cyclotron fluctuations of the plasma. The power level of the e-beams was comparable to that of the injected neutral beams. It was found that injection of the e-beams produced no significant effect on the ion cyclotron fluctuations, the measured plasma parameters, or the particle and power flow of the plasma. The increase in bulk electron temperature and the production of mirror-confined electrons found in previous experiments in which e-beams were injected into a mirror-confined plasma were not observed in this experiment. Analysis of the regions and frequencies of wave creation and absorption within the plasma shows that the plasma density and magnetic field profiles through the plasma strongly affect the resonances encountered by the waves. The steep axial density profiles produced by neutral-beam injection in the TMX experiment are not conducive to efficient coupling of the e-beam energy to the plasma.

  3. Designing Fault-Injection Experiments for the Reliability of Embedded Systems

    NASA Technical Reports Server (NTRS)

    White, Allan L.

    2012-01-01

    This paper considers the long-standing problem of conducting fault-injections experiments to establish the ultra-reliability of embedded systems. There have been extensive efforts in fault injection, and this paper offers a partial summary of the efforts, but these previous efforts have focused on realism and efficiency. Fault injections have been used to examine diagnostics and to test algorithms, but the literature does not contain any framework that says how to conduct fault-injection experiments to establish ultra-reliability. A solution to this problem integrates field-data, arguments-from-design, and fault-injection into a seamless whole. The solution in this paper is to derive a model reduction theorem for a class of semi-Markov models suitable for describing ultra-reliable embedded systems. The derivation shows that a tight upper bound on the probability of system failure can be obtained using only the means of system-recovery times, thus reducing the experimental effort to estimating a reasonable number of easily-observed parameters. The paper includes an example of a system subject to both permanent and transient faults. There is a discussion of integrating fault-injection with field-data and arguments-from-design.

  4. Pellet impact drilling operational parameters: experimental research

    NASA Astrophysics Data System (ADS)

    Kovalyov, A. V.; Ryabchikov, S. Ya; Isaev, Ye D.; Aliev, F. R.; Gorbenko, M. V.; Baranova, A. V.

    2015-02-01

    The article deals with the study of particle-impact drilling that is designed to enhance the rate-of-penetration function in hard and tough drilling environments. It contains the experimental results on relation between drilling parameters and drilling efficiency, the experiments being conducted by means of a specially designed laboratory model. To interpret the results properly a high-speed camera was used to capture the pellet motion. These results can be used to choose optimal parameters, as well as to develop enhanced design of ejector pellet impact drill bits.

  5. Tritium pellet injector for the Tokamak Fusion Test Reactor

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foust, C.R.; Milora, S.L.

    1992-01-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) plasma phase. An existing deuterium pellet injector (DPI) was modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed for frozen pellets ranging in size from 3 to 4 mm in diameter in arbitrarily programmable firing sequences at tritium pellet speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller (PLC). The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were also made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed and the TPI was tested at ORNL with deuterium pellets. Results of the testing program at ORNL are described. The TPI has been installed and operated on TFTR in support of the CY-92 deuterium plasma run period. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and tritium gloveboxes and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  6. Tritium pellet injector for the Tokamak Fusion Test Reactor

    SciTech Connect

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foust, C.R.; Milora, S.L.

    1992-11-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) plasma phase. An existing deuterium pellet injector (DPI) was modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed for frozen pellets ranging in size from 3 to 4 mm in diameter in arbitrarily programmable firing sequences at tritium pellet speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller (PLC). The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were also made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed and the TPI was tested at ORNL with deuterium pellets. Results of the testing program at ORNL are described. The TPI has been installed and operated on TFTR in support of the CY-92 deuterium plasma run period. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and tritium gloveboxes and integrated into TFTR tritium processing systems to provide full tritium pellet capability.

  7. Pellet imaging techniques on ASDEX

    SciTech Connect

    Wurden, G.A. ); Buechl, K.; Hofmann, J.; Lang, R.; Loch, R.; Rudyj, A.; Sandmann, W. )

    1990-01-01

    As part of a USDOE/ASDEX collaboration, a detailed examination of pellet ablation in ASDEX with a variety of diagnostics has allowed a better understanding of a number of features of hydrogen ice pellet ablation in a plasma. In particular, fast gated photos with an intensified Xybion CCD video camera allow in-situ velocity measurements of the pellet as it penetrates the plasma. With time resolution of typically 100 nanoseconds and exposures every 50 microseconds, the evolution of each pellet in a multi-pellet ASDEX tokamak plasma discharge can be followed. When the pellet cloud track has striations, the light intensity profile through the cloud is hollow (dark near the pellet), whereas at the beginning or near the end of the pellet trajectory the track is typically smooth (without striations) and has a gaussian-peaked light emission profile. New, single pellet Stark broadened D{sub {alpha}}D{sub {beta}}, and D{sub {gamma}} spectra, obtained with a tangentially viewing scanning mirror/spectrometer with Reticon array readout, are consistent with cloud densities of 2 {times} 10{sup 17}cm{sup {minus}3} or higher in the regions of strongest light emission. A spatially resolved array of D{sub {alpha}} detectors shows that the light variations during the pellet ablation are not caused solely by a modulation of the incoming energy flux as the pellet crosses rational q-surfaces, but instead are a result of a dynamic, non-stationary, ablation process. 20 refs., 4 figs.

  8. Simulation and experiment research on the proportional pressure control of water-assisted injection molding

    NASA Astrophysics Data System (ADS)

    Zhou, Hua; Chen, Yinglong; Zhang, Zengmeng; Yang, Huayong

    2012-05-01

    Water-assisted injection molding (WAIM), a newly developed fluid-assisted injection molding technology has drawn more and more attentions for the energy saving, short cooling circle time and high quality of products. Existing research for the process of WAIM has shown that the pressure control of the injecting water is mostly important for the WAIM. However, the proportional pressure control for the WAIM system is quite complex due to the existence of nonlinearities in the water hydraulic system. In order to achieve better pressure control performance of the injecting water to meet the requirements of the WAIM, the proportional pressure control of the WAIM system is investigated both numerically and experimentally. A newly designed water hydraulic system for WAIM is first modeled in AMEsim environment, the load characteristics and the nonlinearities of water hydraulic system are both considered, then the main factors affecting the injecting pressure and load flow rate are extensively studied. Meanwhile, an open-loop model-based compensation control strategy is employed to regulate the water injection pressure and a feedback proportional integrator controller is further adopted to achieve better control performance. In order to verify the AMEsim simulation results WAIM experiment for particular Acrylonitrile Butadiene Styrene (ABS) parts is implemented and the measured experimental data including injecting pressure and flow rate results are compared with the simulation. The good coincidence between experiment and simulation shows that the AMEsim model is accurate, and the tracking performance of the load pressure indicates that the proposed control strategy is effective for the proportional pressure control of the nonlinear WAIM system. The proposed proportional pressure control strategy and the conclusions drawn from simulation and experiment contribute to the application of water hydraulic proportional control and WAIM technology.

  9. Design and operation of the pellet charge exchange diagnostic for measurement of energetic confined alphas and tritons on TFTR

    SciTech Connect

    Medley, S.S.; Duong, H.H.; Fisher, R.K.

    1996-05-01

    Radially-resolved energy and density distributions of the energetic confined alpha particles in D-T experiments on TFTR are being measured by active neutral particle analysis using low-Z impurity pellet injection. When injected into a high temperature plasma, an impurity pellet (e.g. Lithium or Boron) rapidly ablates forming an elongated cloud which is aligned with the magnetic field and moves with the pellet. This ablation cloud provides a dense target with which the alpha particles produced in D-T fusion reactions can charge exchange. A small fraction of the alpha particles incident on the pellet ablation cloud will be converted to helium neutrals whose energy is essentially unchanged by the charge transfer process. By measuring the resultant helium neutrals escaping from the plasma using a mass and energy resolving charge exchange analyzer, this technique offers a direct measurement of the energy distribution of the incident high-energy alpha particles. Other energetic ion species can be detected as well, such as tritons generated in D-D plasmas and H or He{sup 3} RF-driven minority ion tails. The diagnostic technique and its application on TFTR are described in detail.

  10. In situ water and gas injection experiments performed in the Hades Underground Research Facility

    SciTech Connect

    Volckaert, G.; Ortiz, L.; Put, M.

    1995-12-31

    The movement of water and gas through plastic clay is an important subject in the research at SCK-CEN on the possible disposal of high level radioactive waste in the Boom clay layer at Mol. Since the construction of the Hades underground research facility in 1983, SCK-CEN has developed and installed numerous piezometers for the geohydrologic characterization and for in situ radionuclide migration experiments. In situ gas and water injection experiments have been performed at two different locations in the underground laboratory. The first location is a multi filter piezometer installed vertically at the bottom of the shaft in 1986. The second location is a three dimensional configuration of four horizontal multi piezometers installed from the gallery. This piezometer configuration was designed for the MEGAS (Modelling and Experiments on GAS migration through argillaceous rocks) project and installed in 1992. It contains 29 filters at distances between 10 m and 15 m from the gallery in the clay. Gas injection experiments show that gas breakthrough occurs at a gas overpressure of about 0.6 MPa. The breakthrough occurs by the creation of gas pathways along the direction of lowest resistance i.e. the zone of low effective stress resulting from the drilling of the borehole. The water injections performed in a filter -- not used for gas injection -- show that the flow of water is also influenced by the mechanical stress conditions. Low effective stress leads to higher hydraulic conductivity. However, water overpressures up to 1.3 MPa did not cause hydrofracturing. Water injections performed in a filter previously used for gas injections, show that the occluded gas hinders the water flow and reduces the hydraulic conductivity by a factor two.

  11. Sequential-Injection Analysis: Principles, Instrument Construction, and Demonstration by a Simple Experiment

    ERIC Educational Resources Information Center

    Economou, A.; Tzanavaras, P. D.; Themelis, D. G.

    2005-01-01

    The sequential-injection analysis (SIA) is an approach to sample handling that enables the automation of manual wet-chemistry procedures in a rapid, precise and efficient manner. The experiments using SIA fits well in the course of Instrumental Chemical Analysis and especially in the section of Automatic Methods of analysis provided by chemistry…

  12. SAG injection in a North Sea stratified reservoir: Flow experiment and simulation

    SciTech Connect

    Hanssen, J.E.; Surguchev, L.M.; Svorstoel, I.

    1994-12-31

    This paper is a study of a novel recovery process for stratified reservoirs with large permeability contrasts. A slug of foaming surfactant is injected alternately with gas, thus by analogy with WAG making this a SAG injection process. A combined experimental and numerical evaluation demonstrating effective diversion by foam and significant recovery potential over WAG of the method is reported. An experiment with the new process was performed in a visual 2-D porous medium flow model approximately scaled to the conditions of a North Sea reservoir that is characterized by high permeability contrast and limited interlayer communication. The experiment showed poor performance of conventional WAG, which swept mainly the high-permeable layer. Placement of a surfactant slug and later foam generation in the swept layer was successfully demonstrated and gave efficient injectant diversion into the other layers, resulting in complete sweep of the reservoir model by continued WAG. In summary the results of this paper show experimentally and by simulation on the same system that SAG injection as implemented here is superior to WAG injection and that the rich observations made in the experimental ca be matched with reasonable accuracy using a commercial simulator with only empirical parameters.

  13. Electron beam injection experiments - Replication of flight observations in a laboratory beam plasma discharge

    NASA Technical Reports Server (NTRS)

    Bernstein, W.; Mcgarity, J. O.; Konradi, A.

    1983-01-01

    Recent electron beam injection experiments in the lower ionosphere have produced two perplexing results: (1) At altitudes from 140 km to 220 km, the beam associated 391.4 nm intensity is relatively independent of altitude despite the decreasing N2 abundance. (2) The radial extent of the perturbed region populated by beam associated energetic electrons significantly exceeds the nominal gyrodiameter for 90 deg injection. A series of laboratory measurements is described in which both of these flight results appear to have been closely reproduced. The laboratory results are reasonably consistent with the transition from a collision dominated to collisionless beam-plasma discharge configuration.

  14. Simulation experiments to generate broadband chaos using dual-wavelength optically injected Fabry-Perot laser

    NASA Astrophysics Data System (ADS)

    Obaid, Hafiz Muhammad; Khawar Islam, Muhammad; Obaid Ullah, Muhammad

    2016-08-01

    Broadband chaos can be generated by beating two wavelengths in a hybrid arrangement of Fabry-Perot (FP) Laser and Fiber ring cavity by injecting dual wavelengths. The bandwidth of generated chaos can be controlled by detuning different modes of FP Laser for beating. The bandwidth of generated chaos increased to many folds depending upon the injected strength and wavelength spacing matched to FP laser modes. The bandwidth enhancement in different simulation experiments conducted is optimized by varying different parameters of FP laser and cavity. The waveforms are analyzed and Lyapunov exponents are calculated in order to validate the existence of high bandwidth non-pulsating chaos.

  15. Fabrication of very high density fuel pellets of thorium dioxide

    NASA Astrophysics Data System (ADS)

    Shiratori, Tetsuo; Fukuda, Kosaku

    1993-06-01

    Very high density ThO 2 pellets were prepared without binders and lubricants from the ThO 2 powder originated by the thorium oxalate, which was aimed to simplify the fabrication process by skipping a preheat treatment. The as-received ThO 2 powder with a surface area of 4.56 m 2/g was ball-milled up to about 9 m 2/g in order to increase the green pellet density as high as possible. Both of the single-sided and the double-sided pressing were tested in the range from 2 to 5 t/cm 2 in the green pellet formation. Sintering temperature was such low as 1550°C. The pellet prepared in this experiment had a very high density in the range from about 96 to 98% TD without any cracks, in which a difference of the pellet density was not recognized in the single-sided pressing methods.

  16. Re-evaluation of a subsurface injection experiment for testing flow and transport models

    SciTech Connect

    Fayer, M.J.; Lewis, R.E.; Engelman, R.E.; Pearson, A.L.; Murray, C.J.; Smoot, J.L. Lu, A.H.; Randall, P.R.; Wegener, W.H.

    1995-12-01

    The current preferred method for disposal of low-level radioactive waste (LLW) at the Hanford Site is to vitrify the wastes so they can be stored in a near-surface, shallow-land burial facility (Shord 1995). Pacific Northwest Laboratory (PNL) managed the PNL Vitrification Technology Development (PVTD) Project to assist Westinghouse Hanford Company (WHC) in designing and assessing the performance of a disposal facility for the vitrified LLW. Vadose zone flow and transport models are recognized as necessary tools for baseline risk assessments of stored waste forms. The objective of the Controlled Field Testing task of the PVTD Project is to perform and analyze field experiments to demonstrate the appropriateness of conceptual models for the performance assessment. The most convincing way to demonstrate appropriateness is to show that the model can reproduce the movement of water and contaminants in the field. Before expensive new experiments are initiated, an injection experiment conducted at the Hanford Site in 1980 (designated the ``Sisson and the Lu experiment``) should be completely analyzed and understood. Briefly, in that test, a solution containing multiple tracers was injected at a single point into the subsurface sediments. The resulting spread of the water and tracers was monitored in wells surrounding the injection point. Given the advances in knowledge, computational capabilities, and models over the last 15 years, it is important to re-analyze the data before proceeding to other experiments and history-matching exercises.

  17. Injection molded nanofluidic chips: fabrication method and functional tests using single-molecule DNA experiments.

    PubMed

    Utko, Pawel; Persson, Fredrik; Kristensen, Anders; Larsen, Niels B

    2011-01-21

    We demonstrate that fabrication of well-defined nanofluidic systems can be greatly simplified by injection molding of thermoplastic polymers. Chips featuring nanochannel arrays, microchannels and integrated interconnects are produced in a single processing step by injection molding. The resulting open channel structures are subsequently sealed by facile plasma-enhanced thermal bonding of a polymer film. This fast, inexpensive and industry-compatible method thus provides a single-use all-polymer platform for nanofluidic lab-on-a-chip applications. Its applicability for nanofluidics is demonstrated by DNA stretching experiments performed on individual double-stranded DNA molecules confined in the injection molded nanochannels. The obtained results are consistent with measurements performed in costly state-of-the-art silica nanochannels, for both straight and tapered channel geometries.

  18. Thomson Scattering Measurements During Local Helicity Injection in the Pegasus Toroidal Experiment

    NASA Astrophysics Data System (ADS)

    Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Reusch, J. A.; Rodriguez Sanchez, C.; Schlossberg, D. J.

    2016-10-01

    Local helicity injection (LHI) is a non-solenoidal startup technique currently being developed at the Pegasus Toroidal Experiment. In LHI, helicity is injected by compact, high-power current sources located in the plasma scrape off layer that drive bulk plasma current through magnetic reconnection. Investigations of the electron temperature and density evolution in LHI plasmas are being pursued using the multi-point Thomson scattering diagnostic on Pegasus. It has been expanded to provide a total of 24 spatial channels using a set of three high-throughput transmission gratings and intensified CCD cameras. Measurements have been made in two separate helicity injector configurations: a low-field-side (outboard midplane) configuration; and a high-field-side (lower divertor) configuration. Initial observations during injection showed 50 injection methods yield peaked temperature profiles in the core; however, a more rapid rise in Te from the edge to the core was observed in the case of outboard injection. Further analysis of electron temperature and density profiles is required to understand the electron confinement scaling associated with LHI. These initial results suggest this startup technique is scalable to MA-class devices with relatively modest injector requirements. Work supported by US DOE Grant DE-FG02-96ER54375.

  19. Influence of pellet size on rat's hoarding behavior.

    PubMed

    Charron, I; Cabanac, M

    2004-09-15

    The body weight threshold for hoarding behavior of rats is routinely used as a means to discern an animal's body weight regulation. We explored whether the size of food pellets would modify hoarding and the hoarding threshold. In Experiment 1, we offered the rats either large (ca. 5 g) or small (ca. 2 g) food pellets on alternate days while keeping their body weights within a narrow range when they were not in the hoarding sessions. The hoarding threshold was not influenced, by food size (312+/-32 g small and 298+/-13 g large pellets, N.S.). On the other hand, the relationship between hoarded food and body mass significantly differed between small and large pellets (ratio of 2.7). Because such a ratio was similar to that of the respective pellet weights, this suggests that the more the rat is deprived of food, the more willing it is, in a predetermined manner, to move about in search of food. Experiment 2 verified this hypothesis: instead of weighing the food hoarded, we counted the number of pellets hoarded. The slopes of the regression lines were similar in both cases, when the pellets were counted and when the hoarded food was weighed. Results showed no significant differences between these two approaches, suggesting that the weight of hoarded food is a good indicator of the number of trips from home to food in the hoarding experiment.

  20. Part weight verification between simulation and experiment of plastic part in injection moulding process

    NASA Astrophysics Data System (ADS)

    Amran, M. A. M.; Idayu, N.; Faizal, K. M.; Sanusi, M.; Izamshah, R.; Shahir, M.

    2016-11-01

    In this study, the main objective is to determine the percentage difference of part weight between experimental and simulation work. The effect of process parameters on weight of plastic part is also investigated. The process parameters involved were mould temperature, melt temperature, injection time and cooling time. Autodesk Simulation Moldflow software was used to run the simulation of the plastic part. Taguchi method was selected as Design of Experiment to conduct the experiment. Then, the simulation result was validated with the experimental result. It was found that the minimum and maximum percentage of differential of part weight between simulation and experimental work are 0.35 % and 1.43 % respectively. In addition, the most significant parameter that affected part weight is the mould temperature, followed by melt temperature, injection time and cooling time.

  1. EXPERIMENTS ON THE EFFECTS OF INJECTION OF EGG-ALBUMEN AND SOME OTHER PROTEIDS

    PubMed Central

    Sollmann, Torald; Brown, E. D.

    1902-01-01

    degeneration of the hepatic epithelium, which are so acute as to be fully developed when death occurs in 1½ hours after injection. Doses of 0.35 grm. per kilo. do not produce this change. Chloretone did not cause the degeneration, but is followed by congestion of the abdominal viscera. 18. Native egg-albumen, injected into the femoral vein of a dog, was followed in one case by a fatal ending with convulsions and coma, after several intervening cases of good health. Further experiments demonstrated that there is no toxicity inherent in fresh egg-albumen, nor can it be developed by breeding the eggs in the shell. The cause of the above fatal issue must therefore be sought in some extraneous toxic agent which contaminated the solution. Muscle-extracts were also devoid of toxicity. Alkali-albumin produces no changes beyond those which may be attributed to the free alkali contained therein. PMID:19866971

  2. Imaging polychromator for density measurements of polystyrene pellet cloud on the Large Helical Device

    SciTech Connect

    Sharov, I. A. Sergeev, V. Yu.; Miroshnikov, I. V.; Tamura, N.; Sudo, S.; Kuteev, B. V.

    2015-04-15

    Experimental data on spatial distributions of a pellet cloud electron density are necessary for the development of many applications of pellet injection, namely, plasma fuelling, discharge control, and plasma diagnostics. An improved approach of electron density measurements inside the cloud of a polystyrene pellet ablating in hot plasma of the large helical device is described. Density values of (1-30) × 10{sup 16} cm{sup −3} depending on the background plasma parameters and distance from the solid pellet were measured.

  3. Discriminative and reinforcing properties of two types of food pellets1

    PubMed Central

    Cruse, Daniel B.; Vitulli, William; Dertke, Max

    1966-01-01

    In Experiment I some discriminative functions of food pellets were studied by developing a multiple schedule of reinforcement (mult FR 30 FI 3) in which the delivery of a standard laboratory food pellet as a reinforcer set the occasion for reinforcement on every 30th response (FR 30), and the delivery of a sucrose food pellet as a reinforcer set the occasion for reinforcement after a 3-min interval (FI 3). Discriminative stimulus control by the type of pellet was also demonstrated by reversing the operant discrimination and having the standard pellet control the FI 3 and the sucrose pellet control the FR 30. In Experiment II a mult FR 30 FR 30 with two bars was developed; a standard food pellet was followed by an FR 30 on Bar 1 and extinction (ext) on Bar 2, while a sucrose pellet was followed by an FR 30 on Bar 2 and ext on Bar 1. A control rat was placed, for comparison, on a mixed (mix) FR 30 FR 30 schedule with two bars, but neither bar correlated with the type of food pellet. In Experiments I and II the similarity between pellet controlled multiple schedules and multiple primed schedules was discussed, as was the comparability of transitions and effectiveness of control between pellet controlled multiple schedules and multiple schedules providing continuous exteroceptive stimuli. PMID:16811298

  4. Owl Pellets and Crisis Management.

    ERIC Educational Resources Information Center

    Anderson, Tom

    2002-01-01

    Describes a press conference that was used as a "teachable moment" when owl pellets being used for instructional purposes were found to be contaminated with Salmonella. The incident highlighted the need for safe handling of owl pellets, having a crisis management plan, and the importance of conveying accurate information to concerned parents.…

  5. Interpretation of injection-withdrawal tracer experiments conducted between two wells in a large single fracture.

    PubMed

    Novakowski, K S; Bickerton, G; Lapcevic, P

    2004-09-01

    Tracer experiments conducted using a flow field established by injecting water into one borehole and withdrawing water from another are often used to establish connections and investigate dispersion in fractured rock. As a result of uncertainty in the uniqueness of existing models used for interpretation, this method has not been widely used to investigate more general transport processes including matrix diffusion or advective solute exchange between mobile and immobile zones of fluid. To explore the utility of the injection-withdrawal method as a general investigative tool and with the intent to resolve the transport processes in a discrete fracture, two tracer experiments were conducted using the injection-withdrawal configuration. The experiments were conducted in a fracture which has a large aperture (>500 microm) and horizontally pervades a dolostone formation. One experiment was conducted in the direction of the hydraulic gradient and the other in the direction opposite to the natural gradient. Two tracers having significantly different values of the free-water diffusion coefficient were used. To interpret the experiments, a hybrid numerical-analytical model was developed which accounts for the arcuate shape of the flow field, advection-dispersion in the fracture, diffusion into the matrix adjacent to the fracture, and the presence of natural flow in the fracture. The model was verified by comparison to a fully analytical solution and to a well-known finite-element model. Interpretation of the tracer experiments showed that when only one tracer, advection-dispersion, and matrix diffusion are considered, non-unique results were obtained. However, by using multiple tracers and by accounting for the presence of natural flow in the fracture, unique interpretations were obtained in which a single value of matrix porosity was estimated from the results of both experiments. The estimate of porosity agrees well with independent measurements of porosity obtained from

  6. Modeling Dynamic Fracture of Cryogenic Pellets

    SciTech Connect

    Parks, Paul

    2016-06-30

    This work is part of an investigation with the long-range objective of predicting the size distribution function and velocity dispersion of shattered pellet fragments after a large cryogenic pellet impacts a solid surface at high velocity. The study is vitally important for the shattered pellet injection (SPI) technique, one of the leading technologies being implemented at ORNL for the mitigation of disruption damage on current tokamaks and ITER. The report contains three parts that are somewhat interwoven. In Part I we formulated a self-similar model for the expansion dynamics and velocity dispersion of the debris cloud following pellet impact against a thick (rigid) target plate. Also presented in Part I is an analytical fracture model that predicts the nominal or mean size of the fragments in the debris cloud and agrees well with known SPI data. The aim of Part II is to gain an understanding of the pellet fracturing process when a pellet is shattered inside a miter tube with a sharp bend. Because miter tubes have a thin stainless steel (SS) wall a permanent deformation (dishing) of the wall is produced at the site of the impact. A review of the literature indicates that most projectile impact on thin plates are those for which the target is deformed and the projectile is perfectly rigid. Such impacts result in “projectile embedding” where the projectile speed is reduced to zero during the interaction so that all the kinetic energy (KE) of the projectile goes into the energy stored in plastic deformation. Much of the literature deals with perforation of the target. The problem here is quite different; the softer pellet easily undergoes complete material failure causing only a small transfer of KE to stored energy of wall deformation. For the real miter tube, we derived a strain energy function for the wall deflection using a non-linear (plastic) stress-strain relation for 304 SS. Using a dishing profile identical to the linear Kirchkoff-Love profile (for lack

  7. Analysis of cavity pressure and warpage of polyoxymethylene thin walled injection molded parts: Experiments and simulations

    NASA Astrophysics Data System (ADS)

    Guerrier, P.; Tosello, G.; Hattel, J. H.

    2015-05-01

    Process analysis and simulations on molding experiments of 3D thin shell parts have been conducted. Moldings were carried out with polyoxymethylene (POM). The moldings were performed with cavity pressure sensors in order to compare experimental process results with simulations. The warpage was characterized by measuring distances using a tactile coordinate measuring machine (CMM). Molding simulations have been executed taking into account actual processing conditions. Various aspects have been considered in the simulation: machine barrel geometry, injection speed profiles, cavity injection pressure, melt and mold temperatures, material rheological and pvT characterization. Factors investigated for comparisons were: injection pressure profile, short shots length, flow pattern, and warpage. A reliable molding experimental database was obtained, accurate simulations were conducted and a number of conclusions concerning improvements to simulation accuracy are presented regarding: pvT data, mesh, short shots, cavity pressure for process control validation as well as molding machine geometry modelling. Eventually, a methodology for improved molding simulations of cavity injection pressure, filling pattern and warpage was established.

  8. Field-scale gas tracing experiment in unsaturated fractured media: from deep injection to surface monitoring

    NASA Astrophysics Data System (ADS)

    Guillon, S.; Pili, E.; Sabroux, J.; Sestier-Carlin, R.; Adler, P. M.

    2011-12-01

    For CO2 sequestration as for other applications, it is important to understand transfer mechanisms of gases in unsaturated fractured rocks from experiment and to develop modeling capabilities. We carried out a field-scale tracing experiment using SF6 with the aim to serve for a forthcoming experiment using CO2. The experimental site was well characterized (mineralogy and fracturation). Transport parameters were estimated from the field, especially permeability and dilution factor. We also evaluated methods to monitor tracer breakthrough at the surface. At the Roselend Natural Laboratory (French Alps), a tunnel provides access to the heart of unsaturated fractured crystalline rocks, at 55 m depth below ground surface. This underground research facility allows studying gas exchange between a 60 m3 chamber isolated at the dead-end of the tunnel and the surface. At the topographic surface, ten 10 meter-long vertical boreholes and one 60 meter-long subhorizontal borehole were used to monitor tracer breakthrough. Stereological analysis of fractures in the tunnel previously led to permeability estimation. Similar analysis of drilled cores (density and orientation of fractures) gave additional permeability estimates in the subsurface. Gas permeability was also determined from pneumatic injection tests in both the injection chamber and subsurface boreholes. Steady-state and transient experiments were analyzed by modeling in real geometry. Long-term continuous pressure monitoring in the isolated chamber and the packed-off boreholes were also used for permeability estimation. We found equivalent air permeability of the order of 10-12 m2 which compares well with previous estimations. Following baseline determination, SF6 was injected at 1000 ppmV in the isolated chamber that was then pressurized to 150 mbar above atmospheric pressure during 2 hours. During all the experiment SF6 concentration was continuously monitored inside the isolated chamber and in front of the isolation

  9. Nuclear fuel pellet transfer escalator

    SciTech Connect

    Huggins, T.B. Sr.; Roberts, E.; Edmunds, M.O.

    1991-09-17

    This patent describes a nuclear fuel pellet escalator for loading nuclear fuel pellets into a sintering boat. It comprises a generally horizontally-disposed pellet transfer conveyor for moving pellets in single file fashion from a receiving end to a discharge end thereof, the conveyor being mounted about an axis at its receiving end for pivotal movement to generally vertically move its discharge end toward and away from a sintering boat when placed below the discharge end of the conveyor, the conveyor including an elongated arm swingable vertically about the axis and having an elongated channel recessed below an upper side of the arm and extending between the receiving and discharge ends of the conveyor; a pellet dispensing chute mounted to the arm of the conveyor at the discharge end thereof and extending therebelow such that the chute is carried at the discharge end of the conveyor for generally vertical movement therewith toward and away from the sintering boat.

  10. Hydroclast and Peperite generation: Experimental Results produced using the Silicate Melt Injection Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    Downey, W. S.; Mastin, L. G.; Spieler, O.; Kunzmann, T.; Shaw, C. S.; Dingwell, D. B.

    2008-12-01

    The Silicate Melt Injection Laboratory Experiment (SMILE) allows for the effusive and explosive injection of molten glass into a variety of media - air, water, water spray, and wet sediments. Experiments have been preformed using the SMILE apparatus to evaluate the mechanisms of "turbulent shedding" during shallow submarine volcanic eruptions and magma/wet-sediment interactions. In these experiments, approximately 0.5 kg of basaltic melt with 5 wt.% Spectromelt (dilithium tetraborate) is produced in an internally heated autoclave at 1150° C and ambient pressure. The molten charge is ejected via the bursting of a rupture disc at 3.5 MPa into the reaction media, situated within the low pressure tank (atmospheric conditions). Preliminary experiments ejecting melt into a standing water column have yielded hydroclasts of basalt. SEM images of the clasts show ubiquitous discontinuous skins ("rinds") that are flaked, peeled, or smeared away in strips. Adhering to the clast surfaces are flakes, blocks, and blobs of detached material, up to 10 μm in size. The presence of partially detached rinds and rind debris likely reflects repeated bending, scraping, impact, and other disruption through turbulent velocity fluctuations. These textures are comparable to littoral explosive deposits at Kilauea Volcano, Hawaii, where lava tubes are torn apart by wave action, the lava is quenched, and thrown back on the beach as loose fragments (hyaloclastite). Preliminary experiments injecting melt into wet sediments show evidence of sediment ingestion and fluidal textures. These results support the interpretation that peperite generation can be driven by hydrodynamic mixing of a fuel and a coolant.

  11. Electrons precipitation stimulated by plasma jets injection in FLUXUS and NORTH STAR active rocket experiments

    NASA Astrophysics Data System (ADS)

    Gavrilov, B.; Erlandson, R.; Lynch, K.; Meng, C.; Podgorny, I.; Pfaff, R.; Stenbaek-Nielsen, H.; Sobyanin, D.; Zetzer, J.

    In Russian-American active rocket experiments FLUXUS (49? N, 47? E, 1997) and NORTH STAR (70? N, 148? W, 1999) high-velocity plasma jets were injected along and across the geomagnetic field respectively. In the both experiments high- density plasma jets pushed out the magnetic field. Later, when the magnetic field penetrated into the plasma jet, plasma was polarized and E=-VxB/c electric field was registered. As a result, Alfvén waves, carrying the field-aligned currents, propagate along the magnetic field lines. If the current density is rather high, the field-aligned electric fields can appear, and electrons would be accelerated along the magnetic field lines. Electron fluxes with energy from several eV to 2 keV were revealed in the both experiments. During NORTH STAR experiment electron fluxes caused by auroral precipitation were also registered

  12. Optimization of Porous Pellets for Phosphate Recovery ...

    EPA Pesticide Factsheets

    The poster presents the preliminary adsorption experiment showing that phosphate concentration is decreasing over time as well as presenting the kinetics models that best fit the data collected over 25 days. The purpose of this project is to find a better material for adsorption of phosphate from water treatment facilities. The material is made into pellets which allow for adsorption and are easier to remove from the system when capacity is reached.

  13. Microorganisms as tracers in groundwater injection and recovery experiments: A review

    USGS Publications Warehouse

    Harvey, R.W.

    1997-01-01

    Modern day injection and recovery techniques designed to examine the transport behavior of microorganisms in groundwater have evolved from experiments conducted in the late 1800s, in which bacteria that form red or yellow pigments were used to trace flow paths through karst and fractured- rock aquifers. A number of subsequent groundwater hydrology studies employed bacteriophage that can be injected into aquifers at very high concentrations (e g., 1013 phage ml-1) and monitored through many log units of dilution to follow groundwater flow paths for great distances, particularly in karst terrain. Starting in the 1930s, microbial indicators of fecal contamination (particularly coliform bacteria and their coliphages) were employed as tracers to determine potential migration of pathogens in groundwater. Several injection and recovery experiments performed in the 1990s employed indigenous groundwater microorganisms (both cultured and uncultured) that are better able to survive under in situ conditions. Better methods for labeling native bacteria (e.g by stable isotope labeling or inserting genetic markers; such as the ability to cause ice nucleation) are being developed that will not compromise the organisms' viability during the experimental time course.

  14. Numerical analysis of experiments with gas injection into liquid metal coolant

    NASA Astrophysics Data System (ADS)

    Usov, E. V.; Lobanov, P. D.; Pribaturin, N. A.; Mosunova, N. A.; Chuhno, V. I.; Kutlimetov, A. E.

    2016-10-01

    Presented paper contains results of a numerical analysis of experiments with gas injection in water and liquid metal which have been performed at the Institute of Thermophysics Russian Academy of Science (IT RAS). Obtained experimental data are very important to predict processes that take place in the BREST-type reactor during the hypothetical accident with damage of the steam generator tubes, and may be used as a benchmark to validate thermo-hydraulic codes. Detailed description of models to simulate transport of gas phase in a vertical liquid column is presented in a current paper. Two-fluid model with closing relation for wall friction and interface friction coefficients was used to simulate processes which take place in a liquid during injection of gaseous phase. It has being shown that proposed models allow obtaining a good agreement between experimental data and calculation results.

  15. H.F. emission related to the Li+ ion beam injected into ionosphere - ``PLAZMA'' rocket experiment

    NASA Astrophysics Data System (ADS)

    Klos, Z.; Zbyszynski, Z.; Agafonov, U. F.; Managadze, G. G.; Mayorov, A. D.

    1993-10-01

    The H.F. emission generated by artificial ion beam injected into ionosphere was observed either with a wave detector and ion gun attached to the rocket through out the flight, or when the gun was deployed on subpayload. Generally the observations show unstructured shape of the H.F. spectrum. In the PLAZMA active rocket experiment - when ionospheric plasma was perturbed by the operation of impulse ion gun, which injected 300 A, 8.3 eV Li+ions - the waves in the 0.1 - 10 MHz frequency range were observed. The results have shown, that when the wave detector and the ion gun are attached to the rocket the emission enhances in the lower as well as in the upper parts of the spectrum. On the other hand only the lower increase is maintained when ion gun is removing away on the subpayload. The observed sequence of H.F. spectra is presented.

  16. Prompt Loss of Energetic Ions during Early Neutral Beam Injection in the National Spherical Torus Experiment

    SciTech Connect

    S.S. Medley; D.S. Darrow; D. Liu; A.L. Roquemore

    2005-03-25

    Early neutral-beam injection is used in the National Spherical Torus Experiment (NSTX) to heat the electrons and slow current penetration which keeps q(0) elevated to avoid deleterious MHD activity and at the same time reduces Ohmic flux consumption, all of which aids long-pulse operation. However, the low plasma current (I{sub p} {approx} 0.5 MA) and electron density (n{sub e} {approx} 1 x 10{sup 13} cm{sup -3}) attending early injection lead to elevated orbit and shine through losses. The inherent orbit losses are aggravated by large excursions in the outer gap width during current ramp-up. An investigation of this behavior using various energetic particle diagnostics on NSTX and TRANSP code analysis is presented.

  17. Single-Well Injection-Withdrawal Experiments for Ground Flow Estimation

    NASA Astrophysics Data System (ADS)

    Holzbecher, E.; Maier, F.

    2012-04-01

    We present a closer look on the Single-Well Injection-Withdrawal Experiment (SWIW) also known as Push-Pull Experiments and its ability to determine the groundwater velocity, as one of the major parameters concerning reservoir management. SWIW are tripartite. One starts with the tracer injection, followed by a quiescence period, where the tracer transport is dominated by the ambient flow field in the reservoir. The last phase is the withdrawal where the tracer break trough curve (BTC) is recorded. From the shape of the BTC, we are able to determine the groundwater velocity. The problem is numerically modeled using COMSOL Multiphysics. We compare with an advanced inversion scheme, based on analytical solutions and implemented in MATLAB. The results show that the BTC of a SWIW experiment is highly dependent on interaction between the parameters for groundwater velocity, pumping rates and the duration of the quiescence phase as well as the reservoir geometry. For the specific tracer applied in the model a minor influence is given by diffusion, dispersion and sorption processes. In dependence of the quiescence time and the groundwater velocity one can distinguish between three characteristic BTC types for the single tracer SWIW. These are given for tracers around the well, tracer between well and stagnation point and tracer beyond the stagnation point. The transition between these different cases is also discussed. The COMSOL Multiphysics model is used to investigate observations from a SWIW experiment performed recently in Japan. The latter is performed in cooperation with Technical University Berlin. Acknowledgements: Gebo, Logro

  18. Studies of energetic confined alphas using the pellet charge exchange diadgnostic on TFTR

    SciTech Connect

    Petrov, M.P.; Budny, R.V.; Duong, H.H.

    1995-07-01

    Results from recent DT experiments on TFIR to measure the energy distribution and radial density profile of fast confined alphas with the use of Li pellets and neutral particle analysis are presented. When a pellet is injected into the plasma, a toroidally extended ablation cloud is formed that travels with the pellet. A small fraction of the fusion alphas incident on the cloud are converted to helium neutrals as a result of electron capture processes. The escaping energetic helium neutrals are analyzed and detected by the neutral particle analyzer. Radially resolved energy spectra of trapped confined alphas in 0.5-2 MeV range and radial alpha density profiles are presented in this paper. The experimental data are compared with modeling results obtained with the TRANSP Monte-Carlo Code and with a specially developed Fokker-Planck Post Processor (FPP) that uses the alpha source distribution produced by TRANSP. Comparison of the experimental data with TRANSP and FPP show that the alphas in the plasma core of sawtooth free discharges in TFIR are well confined and slow down classically. The energy and radial profiles distributions outside the plasma core show the influence of stochastic ripple losses on alphas. Measurements for sawtoothing plasmas show a significant outward radial transport of trapped alphas.

  19. A Cross-Hole, Multi-Year Tracer Injection Experiment in the Volcanic Ocean Crust

    NASA Astrophysics Data System (ADS)

    Fisher, A. T.; Neira, N. M.; Wheat, C. G.; Clark, J. F.; Becker, K.; Hsieh, C. C.; Rappe, M. S.

    2014-12-01

    We present preliminary results from the first cross-hole tracer injection experiment in the volcanic ocean crust. The test site is on 3.5 to 3.6 M.y. old seafloor on the eastern flank of the Juan de Fuca Ridge. Six borehole subseafloor observatories (CORKs) were installed during three scientific ocean drilling expeditions, five arrayed along a 1 km profile aligned with the strike of underlying abyssal hills (Holes 1026B, 1301A/B, and 1362A/B), and one offset 2.4 km to the east (1027C). Before installing the sixth CORK in Hole 1362B, in 2010, we injected a mixture of tracers (dissolved gas, metal salts, particles) during 24 hours into the upper ocean crust. Seafloor samplers connected CORKs, sampling from different locations in the crust, were recovered during servicing expeditions in 2011 and 2013; downhole samplers that contain records from the full four years following tracer injection will be recovered in Summer 2014. Analyses of dissolved gas tracers collected with wellhead samplers through 2013 suggest that the dominant flow direction in upper basement is south to north, as inferred from regional thermal data and the chemistry of geochemical (pore fluid and borehole) samples. The apparent tracer flow rate in upper basement is on the order of meters/day, but calculations are complicated by an incomplete CORK seal in Hole 1301A, which resulted in discharge from this system that also "pulled" water and tracer to the south. Samples were collected from the tracer injection borehole, Hole 1362B, and a sampling site 200 m to the north, Hole 1362A, beginning one year after tracer injection, after opening a large-diameter ball valve on the wellhead of Hole 1362B to initiate a long-term free flow experiment. Analyses of these samples suggest that much of the tracer injected in 2010 remained close to Hole 1362B rather than being advected and dispersed into the formation. It also appears that much of the tracer transport to Hole 1362A occurred within one or more

  20. Development Of A Methodology For The Application Of Synthetic DNA In Stream Tracer Injection Experiments

    NASA Astrophysics Data System (ADS)

    Foppen, J.; Bogaard, T.

    2013-12-01

    Stream tracer injection experiments are useful for characterizing hydrological and biogeochemical processes in streams. We used non-conservative synthetic DNA and conservative NaCl in six instantaneous tracer injection experiments in streams in the Benelux. The main aim was to compare the performance of injected synthetic DNA tracer 'T23' with NaCl. In all experiments, the shapes of the T23 and NaCl breakthrough curves (BTCs) were similar. Recovered T23 mass ranged from 2.9-52.6%, while recovered NaCl tracer mass ranged from 66.7% to complete mass recovery. In batch experiments, T23 decay was not detected. However, in those batches, we observed an unexplained initial T23 mass loss of 40-97%. In batches with sediment, T23 attachment rate coefficients ranged from close to zero to 0.2 hr-1. Advective and dispersive transport parameters of both NaCl and T23 fitted with STAMMT-L were similar. However, compared to T23, fitted storage zone areas of NaCl were 2-5 times larger, while storage zone exchange coefficients were two times larger. Fitted mass dilution factors of T23 ranged from 1.6-34.8. Together, these results pointed towards the disappearance of a part of the T23 mass due to both initial losses and attachment or sorption of T23 mass in those storage zone(s), while decay was not important. Our research demonstrated that artificial DNA can be a valuable tool to determine advective and dispersive transport in brooks, but not to assess solute mass exchange processes related to surface transient storage or hyporheic exchange.

  1. Short-interval multi-laser Thomson scattering measurements of hydrogen pellet ablation in LHD

    SciTech Connect

    Yasuhara, R. Sakamoto, R.; Yamada, I.; Motojima, G.; Hayashi, H.

    2014-11-15

    Thomson scattering forms an important aspect of measuring the electron density and temperature profiles of plasmas. In this study, we demonstrate Thomson scattering measurements obtained over a short interval (<1 ms) by using an event triggering system with a multi-laser configuration. We attempt to use our system to obtain the electron temperature and density profiles before and immediately after pellet injection into the large helical device. The obtained profiles exhibit dramatic changes after pellet injection as per our shot-by-shot measurements. We believe that this measurement technique will contribute towards a better understanding of the physics of the pellet deposition.

  2. A self-injection acceleration test experiment for the FLAME laser

    NASA Astrophysics Data System (ADS)

    Labate, L.; Anelli, F.; Bacci, A.; Batani, D.; Bellaveglia, M.; Benedetti, C.; Benocci, R.; Cacciotti, L.; Cecchetti, C. A.; Ciricosta, O.; Clozza, A.; Cultrera, L.; Di Pirro, G.; Drenska, N.; Faccini, R.; Ferrario, M.; Filippetto, D.; Gallo, S.; Fioravanti, S.; Gamucci, A.; Gatti, G.; Ghigo, A.; Giulietti, A.; Giulietti, D.; Köster, P.; Levato, T.; Lollo, V.; Pace, E.; Pathak, N.; Rossi, A.; Serafini, L.; Turchetti, G.; Vaccarezza, C.; Valente, P.; Vicario, C.; Gizzi, L. A.

    2010-10-01

    A 250-TW laser system (FLAME - Frascati laser for acceleration and multidisciplinary experiments) is now in its commissioning phase in a new laboratory at LNF-INFN in the framework of the PLASMONX (Plasma acceleration and monochromatic X-ray generation) project. The laser will deliver<25 fs duration pulses with an energy up to 6 J, at a 10 Hz repetition rate. An ad hoc target area has also been designed and is currently being set up, allowing the first test experiments of electron laser wakefield acceleration to be carried out over the next few months in a safe, radiation-protected environment. An overview of the main features of the laser system and target area is given, along with a survey of the design and set-up of the self-injection test experiment, which is expected to reach the production of sub-GeV electron bunches.

  3. Probing RFP Density Limits and the Interaction of Pellet Fueling and NBI Heating on MST

    NASA Astrophysics Data System (ADS)

    Caspary, K. J.; Chapman, B. E.; Anderson, J. K.; Limbach, S. T.; Oliva, S. P.; Sarff, J. S.; Waksman, J.; Combs, S. K.; Foust, C. R.

    2013-10-01

    Pellet fueling on MST has previously achieved Greenwald fractions of up to 1.5 in 200 kA improved confinement discharges. Additionally, pellet fueling to densities above the Greenwald limit in 200 kA standard discharges resulted in early termination of the plasma, but pellet size was insufficient to exceed the limit for higher current discharges. To this end, the pellet injector on MST has been upgraded to increase the maximum fueling capability by increasing the size of the pellet guide tubes, which constrain the lateral motion of the pellet in flight, to accommodate pellets of up to 4.0 mm in diameter. These 4.0 mm pellets are capable of triggering density limit terminations for MST's peak current of 600 kA. An unexpected improvement in the pellet speed and mass control was also observed compared to the smaller diameter pellets. Exploring the effect of increased density on NBI particle and heat deposition shows that for MST's 1 MW tangential NBI, core deposition of 25 keV neutrals is optimized for densities of 2-3 × 1019 m-3. This is key for beta limit studies in pellet fueled discharges with improved confinement where maximum NBI heating is desired. An observed toroidal deflection of pellets injected into NBI heated discharges is consistent with asymmetric ablation due to the fast ion population. In 200 kA improved confinement plasmas with NBI heating, pellet fueling has achieved a Greenwald fraction of 2.0. Work supported by US DoE.

  4. The potential of active, in-situ, relativistic electron injection experiments for geospace research

    NASA Astrophysics Data System (ADS)

    Nicolls, M. J.; Marshall, R. A.; Sanchez, E. R.

    2012-12-01

    Active, space-based particle injection experiments have enabled scientific investigations of space plasmas since at least the 1950s. However, these controlled experiments were mainly based on comparatively low energy electron beams (<40 keV) and higher energy experiments have not been undertaken, presumably due in major part to technological unfeasibility. It is now possible to generate relativistic electron beams (500 keV to ~10 MeV) with compact linear accelerators efficiently (~20% wall to beam efficiency is achievable) and with small devices (significant advances in high gradient acceleration have been achieved). We outline the scientific need and technological feasibility of controlled, relativistic, space-based electron beams. Potential scientific investigations include: (a) Atmospheric interactions, involving investigations of ionization and recombination processes, optical and x-ray emissions, modification of the atmosphere potential structure, and discharges; (b) Beam-plasma interactions, which include the interaction of injected relativistic electron beams with whistler waves and the potential generation of VLF signatures via cyclotron and Landau resonances; and (c) Magnetic mapping, including using electron beams as tracers of magnetic field geometry during variable geomagnetic conditions and the wave-particle interactions triggered by the propagation of relativistic electron beams along magnetic field lines.

  5. Effects of Water Injection into Fractured Geothermal Reservoirs: A Summary of Experience Worldwide

    SciTech Connect

    Horne, Roland N.

    1982-06-01

    Reinjection of water into fractured geothermal reservoirs holds potential both for improvement and degradation of total energy recovery. The replacement of reservoir fluid can mean support of placement of reservoir pressures and also more efficient thermal energy recovery, but at the same time the premature invasion of reinjected water back into production wells through high permeability fractures can reduce discharge enthalpy and hence deliverability and useful energy output. Increases in reservoir pressure and maintenance of field output have been observed in operating fields, but unfortunately so too have premature thermal breakthroughs. The design of reinjection schemes, therefore, requires careful investigation into the likely effects, using field experimentation. This paper summarizes field experience with reinjection around the world, with the intention of elucidating characteristics of possible problems. The results summarized in this paper fall into three categories of interest: permeability changes dye to injection (both increases and decreases); the path followed by injected water (as indicated by tracer tests); and the thermal and hydraulic influences of injection on the reinjection well itself and on surrounding producers. [DJE-2005

  6. I am just a 'maae' (mother): experiences of mothers injecting drugs in Thailand.

    PubMed

    Haritavorn, Niphattra

    2016-09-01

    Mothers who use drugs face much discriminatory action as society in general finds female drug users' modes of caring for their children unacceptable. In this article, I explore the ways in which Thai women's injecting practices revolve around the role of mother 'maae' and the ways they employ tactics to challenge the motherhood discourse. This article draws on in-depth interviews with 30 Thai mothers injecting drugs. Thai mothers injecting drugs struggled with stigma and self-blame. They internalise the values of the mother 'maae', that is, what the mother is supposed to be; attempting to combine their drug use with their parental responsibilities. Having a child is treated as a means for many women to manage the hostile social impacts of being an addict mother as well as anxieties about the future of their children. To maintain identity as a mother, as gender norms dictates, the mothers employ several tactics to defend that identity from the threats. In conclusion, the findings have implications for harm reduction and reproductive services for women using drugs in Thailand; health care providers need to appreciate the ramifications of the lived experiences of the women who take drugs.

  7. Vas deferens occlusion by percutaneous injection of polyurethane elastomer plugs: clinical experience and reversibility.

    PubMed

    Zhao, S C

    1990-05-01

    A non-incision method of vas occlusion based on the percutaneous injection of polyurethane elastomer solution to form plugs is described. The results are based on clinical experience in 12,000 men in which only 56 cases of minor complications were recorded. Follow-up of 500 men for up to 3 years demonstrated an azoospermia rate of 98%. Plugs have been removed from 86 men and, to date, 51 have made their wives pregnant. In those from which the plugs have been removed for more than 1 year (n = 31), the pregnancy rate is 100%.

  8. Pelletization of fine coals. Technical progress report, March 1, 1992--May 31, 1992

    SciTech Connect

    Sastry, K.V.S.

    1992-09-01

    The first step consisted of producing a batch of seed pellets (in the size range {minus}4.75+4.00 mm) by pelletizing of 200 g of ground coal with desired additives (surface active agents and binders) and moisture content for 800 revolutions. The seed pellets are obtained by sieving the output from the batch drum. The second step involved the production of finished size pellets by layering the seed pellets with stepwise addition of moist feed which is again produced with desired additives and moisture content. Specifically, 25 g of the {minus}4.75+4.00 mm seed pellets are placed in the drum and 20 g of moist fluffy feed is added every 80 revolutions for five times. After 400 revolutions the pellets are sieved on the 4.75 mm screen and the screen undersize which corresponds to new seeds generated during the layering cycles is discarded. Now, 30 g of moist fluffy feed is added every 50 revolutions for five more cycles. These layered pellets are sieved again and the {minus}9.5+8.00 mm pellets. Coal agglomerates produced by the above described technique are nice and spherical. With our past experience with iron ore pelletization we learnt that as long as sufficient fluffy feed is available for the consumption by the seed pellets, they generally grow by forming layers consuming the feed rather than grow by coalescence. This is found to be true in the case of coal also. Growth by coalescence of coal pellets is found to yield raspberry type uneven agglomerates. After ascertaining the possibility of producing nice spherical pellets, several experiments have been conducted to develop the above standard procedure for making pellets in a reproducible way and testing them for their quality.

  9. Injection Moulding of Wood Powder with Low Binder Content

    NASA Astrophysics Data System (ADS)

    Miki, Tsunehisa; Takakura, Norio; Iizuka, Takashi; Yamaguchi, Katsuhiko; Imanishi, Hiroshi; Kanayama, Kouzou

    This study is aimed at exploring possibilities to improve the injectability of wood powder and the mechanical properties of the injected product while keeping the amount of binder to its minimum. In the preliminary experiment, injection moulding of Japanese cedar wood powder was conducted. The effects of binder content (PE; pellet-size) and nozzle temperature on the tensile strength and strain at break of the product were investigated. Results showed that under such conditions, injection moulding of wood powder only was not possible due to insufficient fluidity. Increasing the binder content and the nozzle temperature resulted to a decrease in the maximum injection pressure and improvement in the fluidity of the powder. Using the same PE content, increasing the temperature resulted to an increase in tensile strength of the injected product. However, the strain at break was decreased. Moreover, at PE content below 50%, the strength and strain decreased considerably.

  10. High pressure jet injection of viscous solutions for endoscopic submucosal dissection (ESD): first clinical experience

    PubMed Central

    Pioche, Mathieu; Lépilliez, Vincent; Déprez, Pierre; Giovannini, Marc; Caillol, Fabrice; Piessevaux, Hubert; Rivory, Jérôme; Guillaud, Olivier; Ciocîrlan, Mihai; Salmon, Damien; Lienhart, Isabelle; Lafon, Cyril; Saurin, Jean-Christophe; Ponchon, Thierry

    2015-01-01

    Background: Long lasting elevation is a key factor during endoscopic submucosal dissection (ESD) and can be obtained by water jet injection of saline solution or by viscous macromolecular solutions. In a previous animal study, we assessed the Nestis Enki II system to combine jet injection and viscous solutions. In the present work, we used this combination in humans in different sites of the digestive tract. Methods: We retrospectively report all of the consecutive ESD procedures performed with jet injection of viscous solutions in four centers. Information was collected about the lesion, the procedure, the histological result, and the outcomes for the patient. Results: In total, 45 resections were completed by six operators: five experts and one beginner with only one previous experience in human ESD. Lesions were located in the esophagus (10), the stomach (11), the duodenum (1), the colon (1) and the rectum (22). Average maximal lesion diameter was 4.8 cm (SD 2.4, range 2 – 11 cm), average lesion surface area was 19.8 cm2 (SD 17.7, range 2.2 – 72 cm2), and average duration of procedure was 79.9 min (SD 50.3 min, range 19 – 225 min). ESD could be conducted while the endoscope was retroflexed at its maximum in 26 cases. Four adverse events were observed: two diminutive perforations and two delayed bleeding occurrences treated conservatively. The R0 resection rate was 91.1 %. The catheter was obstructed in six occurrences of bleeding. Conclusion: Endoscopic submucosal dissection using high pressure injection of viscous macromolecular solutions is safe and effective in different parts of the digestive tract. It does not impede working with the endoscope in the maximal retroflexed position. PMID:26356488

  11. Quantitative effects of pelleting on performance, gastrointestinal tract and behaviour of meat-type chickens.

    PubMed

    Nir, I; Twina, Y; Grossman, E; Nitsan, Z

    1994-09-01

    1. In an attempt to quantify the effects of "degree" of pelleting, two experiments were conducted. Diets were prepared by mixing together a mash composed mainly of maize (experiment 1) or sorghum (experiment 2) with soft pellets, or soft pellets mixed with hard pellets. 2. The pelleting degrees (PDs) were as follows: 0 mash; 0.5 mixture of soft pellets and mash 1 to 1; 1 soft pellets pelleted once; 1.5 mixture of soft and hard pellets 1 to 1; 2 hard pellets pelleted twice. 3. In experiment 2, the weight and length of the digestive organs were determined as well as digestive enzyme activities. In both experiments, the behaviour recorded was eating, standing, sitting and drinking. 4. Food intake and body weight gain were related to the degree of pelleting in a curvilinear manner. PD had a positive effect up to a peak (1 to 1.5 PD), after which its effect decreased. Food efficiency was not related to PD. In experiment 1, food efficiency of PDs 1 to 2 were superior to PDs 0 to 0.5 and in experiment 2, PDs 1.5 to 2 were superior to PD 0. 5. The relative weight of the gizzard was reduced by pelleting, whereas pelleting increased the relative weight of abdominal fat. The content of the crop was not affected by PD, whereas that of the proventriculus was lowest in the PD 2 group. Gizzard content was inversely related to PD. Pelleting reduced the length of the jejunum and ileum: which were shortened by about 15% with PDs 1 to 2, as compared to PD 0. The weight/length ratio of the jejunum and ileum tended to increase with increasing PD to a peak at PD 1.5, and to decrease thereafter. 6. Trypsin activity in the pancreas and amylase activity in the intestinal content were reduced by pelleting. 7. Chicks fed pelleted diets were less active: they 'sat' more and spent less time eating than their mash-fed counterparts.

  12. Simulation of Pellet Ablation

    NASA Astrophysics Data System (ADS)

    Parks, P. B.; Ishizaki, Ryuichi

    2000-10-01

    In order to clarify the structure of the ablation flow, 2D simulation is carried out with a fluid code solving temporal evolution of MHD equations. The code includes electrostatic sheath effect at the cloud interface.(P.B. Parks et al.), Plasma Phys. Contr. Fusion 38, 571 (1996). An Eulerian cylindrical coordinate system (r,z) is used with z in a spherical pellet. The code uses the Cubic-Interpolated Psudoparticle (CIP) method(H. Takewaki and T. Yabe, J. Comput. Phys. 70), 355 (1987). that divides the fluid equations into non-advection and advection phases. The most essential element of the CIP method is in calculation of the advection phase. In this phase, a cubic interpolated spatial profile is shifted in space according to the total derivative equations, similarly to a particle scheme. Since the profile is interpolated by using the value and the spatial derivative value at each grid point, there is no numerical oscillation in space, that often appears in conventional spline interpolation. A free boundary condition is used in the code. The possibility of a stationary shock will also be shown in the presentation because the supersonic ablation flow across the magnetic field is impeded.

  13. Transient Changes in Shallow Groundwater Chemistry During the MSU-ZERT CO2 Injection Experiment

    NASA Astrophysics Data System (ADS)

    Zheng, L.; Apps, J. A.; Spycher, N.; Birkholzer, J. T.; Kharaka, Y. K.; Thordsen, J. J.; Kakouros, E.; Trautz, R. C.

    2009-12-01

    The Montana State University Zero Emission Research and Technology (MSU-ZERT) field experiment at Bozeman, Montana, is designed to evaluate atmospheric and near-surface monitoring and detection techniques applicable to the potential leakage of CO2 from deep storage reservoirs. However, the experiment also affords an excellent opportunity to investigate the transient changes in groundwater chemical composition in response to increasing CO2 partial pressures. Between July 9 and August 7, 2008, 300 kg/day of food-grade CO2 was injected into shallow groundwater through a horizontal perforated pipe about 2-2.3 m below the ground surface. Changes in groundwater quality were investigated through comprehensive chemical analyses of 80 water samples taken before, during and following CO2 injection from 10 shallow observation wells located 1-6 m from the injection pipe, and from two distant monitoring wells. Field and laboratory analyses suggest rapid and systematic changes in pH, alkalinity, and conductance, as well as increases in the aqueous concentrations of both major and trace element species. A principal component analysis and independent thermodynamic interpretation of the water quality analyses were conducted. Results were interpreted in conjunction with a mineralogical characterization of the shallow sediments and a review of historical records of the chemical composition of rainfall at neighboring monitoring sites. The interpretation permitted tentative identification of a complex array of adsorption/desorption, ion exchange, precipitation/dissolution, oxidation/reduction and infiltration processes that were operative during the test. Geochemical modeling was conducted using TOUGHREACT to test whether the observed water quality changes were consistent with the hypothesized processes, and very good agreement was obtained with respect to the behavior of both major and trace elements.

  14. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  15. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  16. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  17. 46 CFR 148.325 - Wood chips; wood pellets; wood pulp pellets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Wood chips; wood pellets; wood pulp pellets. 148.325... § 148.325 Wood chips; wood pellets; wood pulp pellets. (a) This part applies to wood chips and wood pulp... cargo hold. (b) No person may enter a cargo hold containing wood chips, wood pellets, or wood...

  18. The electric field structure of auroral arcs as determined from barium plasma injection experiments

    NASA Technical Reports Server (NTRS)

    Wescott, E. M.

    1981-01-01

    Barium plasma injection experiments have revealed a number of features of electric fields in and near auroral forms extending from a few hundred to many thousands of km in altitude. There is evidence for V-type potential structures over some auroras, but not in others. For some auroral arcs, large E fields are found at ionospheric altitudes outside the arc but the E field inside the arc is near zero. In a few other auroras, most recently one investigated in an experiment conducted from Poker Flat on March 22, 1980, large, rapidly fluctuating E fields were detected by barium plasma near 600 km altitude. These E fields suggest that the motion of auroral rays can be an effect of low-altitude electric fields, or that V-type potential structures may be found at low altitudes.

  19. Investigation of oil injection into brine for the strategic petroleum reserve : hydrodynamics experiments with simulant liquids.

    SciTech Connect

    Castaneda, Jaime N.; Shollenberger, Kim Ann; Torczynski, John Robert; Cote, Raymond O.; Barney, Jeremy; O'Hern, Timothy John

    2003-10-01

    An experimental program is being conducted to study a proposed approach for oil reintroduction in the Strategic Petroleum Reserve (SPR). The goal is to assess whether useful oil is rendered unusable through formation of a stable oil-brine emulsion during reintroduction of degassed oil into the brine layer in storage caverns. This report documents the first stage of the program, in which simulant liquids are used to characterize the buoyant plume that is produced when a jet of crude oil is injected downward from a tube into brine. The experiment consists of a large transparent vessel that is a scale model of the proposed oil injection process at the SPR. An oil layer is floated on top of a brine layer. Silicon oil (Dow Corning 200{reg_sign} Fluid, 5 cSt) is used as the simulant for crude oil to allow visualization of the flow and to avoid flammability and related concerns. Sodium nitrate solution is used as the simulant for brine because it is not corrosive and it can match the density ratio between brine and crude oil. The oil is injected downward through a tube into the brine at a prescribed depth below the oil-brine interface. Flow rates are determined by scaling to match the ratio of buoyancy to momentum between the experiment and the SPR. Initially, the momentum of the flow produces a downward jet of oil below the tube end. Subsequently, the oil breaks up into droplets due to shear forces, buoyancy dominates the flow, and a plume of oil droplets rises to the interface. The interface is deflected upward by the impinging oil-brine plume. Two different diameter injection tubes were used (1/2-inch and 1-inch OD) to vary the scaling. Use of the 1-inch injection tube also assured that turbulent pipe flow was achieved, which was questionable for lower flow rates in the 1/2-inch tube. In addition, a 1/2-inch J-tube was used to direct the buoyant jet upwards rather than downwards to determine whether flow redirection could substantially reduce the oil-plume size and the

  20. Electrical resistivity tomography as a tool for monitoring CO2 injection: Demonstration of leakage detection during bench-scale experiments

    NASA Astrophysics Data System (ADS)

    Breen, S. J.; Carrigan, C. R.; LaBrecque, D. J.; Detwiler, R. L.

    2011-12-01

    Field-scale studies have shown Electrical Resistivity Tomography (ERT) to be an effective tool for imaging resistivity anomalies and monitoring infiltration events in the near subsurface. ERT also shows potential for monitoring CO2 injections, despite deployment challenges in the deep subsurface. We present results from analog bench-scale experiments aimed at evaluating the ability of ERT to quantify the volume and spatial distribution of a gas injected into a brine-saturated porous medium. We injected measured volumes of gas into translucent chambers filled with quartz sand, lined with electrodes, and saturated with a low resistivity salt solution. Between injections, a CCD camera captured high-resolution images, and an ERT data acquisition system scanned the chamber. Using the CCD images, quantitative visualization techniques resulted in high-resolution measurements of the spatial distribution and saturation of the injected gas. Direct comparison to inverted resistivity fields then provided a quantitative measure of the ability of ERT to estimate the total volume of injected gas and its spatial distribution within the chamber. We present results from two experiments designed to represent different injection scenarios: (A) low injection rate and strong capillary barrier, and (B) high injection rate and weaker capillary barrier. Results show that ERT provides good estimates of the shape, size and location of the primary gas plume, but underestimates gas content and does not detect thin pathways of gas from the injection port or within the overlying capillary barrier. However, ERT measurements did detect a change in saturation within the primary plume caused by leakage through the capillary barrier in (B), demonstrating the potential utility of ERT as a leakage-monitoring tool. Repeated ERT scans during our experiments led to degradation in data quality that corresponded with an increase in measured contact resistance. Decreased data quality over time is clearly a

  1. Is peer injecting a form of intimate partner abuse? A qualitative study of the experiences of women drug users.

    PubMed

    Wright, Nat M J; Tompkins, Charlotte N E; Sheard, Laura

    2007-09-01

    Women are over-represented as the recipients of injections of illicit drugs and are often injected by their intimate partners. This study used qualitative research to explore women drug users' experiences of abuse from intimate partners when being injected with illicit drugs. In-depth interviews were conducted with 45 women drug users in the city of Leeds and the area of North Nottinghamshire, UK. The practice of peer injecting illicit drugs places women recipients at risk of physical, economic and emotional abuse from their male intimate partner injectors. However, this was not a universal feature. In trusting, supportive intimate partner relationships peer injecting took place through reciprocal arrangements. Moving away from peer injecting was technically and emotionally difficult for women and rarely straightforward. The implications of the work are discussed as clinicians and wider drug service staff should be aware of the possibility of abuse and enquire about peer injecting when consulting with women injecting drug users. However, clinicians should avoid working within a simplistic clinical framework that views all peer injecting as intrinsically abusive. More research is needed to provide evidence for best practice. Until then, generic principles of best practice management of intimate partner abuse could apply, including enhancing women's motivation to effect change in an abusive situation.

  2. The Psychosocial Consequences of BOTOX Injections for Spasmodic Dysphonia: A Qualitative Study of Patients’ Experiences

    PubMed Central

    Baylor, Carolyn R.; Yorkston, Kathryn M.; Eadie, Tanya L.; Maronian, Nicole C.

    2009-01-01

    Summary Objectives/Hypothesis The purpose of this study is to examine the psychosocial consequences of BOTOX® (Allergan, Inc. Irvine, CA) treatment for spasmodic dysphonia (SD). This article also explores how patients judge the success of treatment and make decisions about future treatment based on psychosocial issues relevant to them. Study Design This study follows the phenomenological tradition of qualitative inquiry in which the objective is to explore the lived experiences of a group of persons who share a common phenomenon, in this case receiving BOTOX injections for SD. Methods Six adults with SD who had been receiving BOTOX injections on a long-term basis participated in face-to-face interviews. The interviews were recorded, transcribed, and analyzed according to phenomenological guidelines to identify consistent themes as well as differences among participants’ experiences. Results The results are summarized in three primary themes that suggest (1) participants’ experiences vary over time based on changes in factors such as lifestyle and personal priorities; (2) BOTOX has multidimensional psychosocial implications in physical, personal, and social domains; and (3) participants individualize their treatment regimens, taking into consideration the burden of treatment, scheduling priorities, and other strategies to maximize the benefits of BOTOX. Conclusions Based on this study, suggestions are provided for future research into a psychosocial outcome measurement, including longitudinal evaluations that accommodate changing patient priorities over time; multidimensional evaluations that incorporate physical, personal, and social issues; evaluations that include a measure of the burden of treatment; and evaluations that support a shared decision-making model with the voice clinicians. PMID:16564675

  3. Complementary effects of torrefaction and co-pelletization: Energy consumption and characteristics of pellets.

    PubMed

    Cao, Liang; Yuan, Xingzhong; Li, Hui; Li, Changzhu; Xiao, Zhihua; Jiang, Longbo; Huang, Binbin; Xiao, Zhihong; Chen, Xiaohong; Wang, Hou; Zeng, Guangming

    2015-06-01

    In this study, complementary of torrefaction and co-pelletization for biomass pellets production was investigated. Two kinds of biomass materials were torrefied and mixed with oil cake for co-pelletization. The energy consumption during pelletization and pellet characteristics including moisture absorption, pellet density, pellet strength and combustion characteristic, were evaluated. It was shown that torrefaction improved the characteristics of pellets with high heating values, low moisture absorption and well combustion characteristic. Furthermore, co-pelletization between torrefied biomass and cater bean cake can reduce several negative effects of torrefaction such as high energy consumption, low pellet density and strength. The optimal conditions for energy consumption and pellet strength were torrefied at 270°C and a blending with 15% castor bean cake for both biomass materials. The present study indicated that compelmentary performances of the torrefaction and co-pelletization with castor bean cake provide a promising alternative for fuel production from biomass and oil cake.

  4. Comparison of Subjective Experiences and Effectiveness of First-Generation Long-Acting Injectable Antipsychotics and Risperidone Long-Acting Injectables in Patients With Schizophrenia.

    PubMed

    Chen, Wen-Yin; Lin, Shih-Ku

    2016-10-01

    We conducted a cross-sectional study to compare the subjective experiences and clinical effects of first-generation long-acting injectable (FGA-LAI) antipsychotics with those of risperidone long-acting injectables (RIS-LAIs) in 434 schizophrenia patients. Compared with the RIS-LAI group, the patients treated with FGA-LAIs had a significantly longer duration of illness and LAI treatment and were older. Our results suggest that patients treated with FGA-LAI have more satisfactory subjective experiences compared with patients treated with RIS-LAI and that both FGA-LAI and RIS-LAI treatments can prevent relapses and hospitalization. Additional longitudinal studies determining the long-term benefits of RIS-LAI are warranted.

  5. Can adult and juvenile European rabbits be differentiated by their pellet sizes?

    NASA Astrophysics Data System (ADS)

    Delibes-Mateos, Miguel; Rouco, Carlos; Villafuerte, Rafael

    2009-03-01

    Recently, a new method for differentiating juvenile and adult rabbits based on faecal pellet size was published. According to this method, pellets >6 mm diameter are inferred to be deposited by adults, while those <6 mm are inferred to be from juveniles or kittens. In this study, we designed a simple experiment to test the accuracy of this methodology. Twelve adult rabbits were housed in individual outdoor cages and their pellets were removed every day for 10 consecutive days. Pellets were separated using a sieve according to their size and counted. Results showed that adult rabbits produce pellets >6 mm diameter in the same proportion as those <6 mm. We also observed a strong influence of the individual rabbit on pellet size; some rabbits produce a high proportion of pellets >6 mm, whereas others deposit mostly pellets <6 mm in size. Our findings demonstrate that pellet size is unsuitable for aging wild rabbits. Field biologists should therefore be cautious when employing the pellet size method of age determination in other wild animals in the absence of validating studies.

  6. Transport simulations of the pre-thermal-quench phase in ASDEX Upgrade massive gas injection experiments

    NASA Astrophysics Data System (ADS)

    Fable, E.; Pautasso, G.; Lehnen, M.; Dux, R.; Bernert, M.; Mlynek, A.; the ASDEX Upgrade Team

    2016-02-01

    The pre-thermal-quench (PTQ) phase of the massive gas injection (MGI) scenario to terminate the tokamak plasma discharge is studied by means of one-dimensional (1D) transport simulations. This phase is characterized by the cold-front penetration in the hot plasma after the gas has been released from the valves, and before the actual thermal quench takes place, with consequent plasma disruption at lower stored energy. The comparison between the simulations and the ASDEX Upgrade (AUG) experiments allows to gain insight in the observed dependencies and time scales. Despite the genuine three-dimensional structure of the problem, it is shown that the 1D simulations are already giving experimentally relevant answers, the reason for which will be discussed in detail. Influence of unknown parameters and simplifying assumptions are also discussed.

  7. Laser Blow-Off Impurity Injection Experiments at the HSX Stellarator

    NASA Astrophysics Data System (ADS)

    Clark, C.; Anderson, D. T.; Anderson, F. S. B.; Likin, K. M.; Talmadge, J. N.; Zhai, K.; Lore, J.

    2011-10-01

    Experiments are under way to measure impurity transport in a quasisymmetric stellarator for the first time. A laser blow-off impurity injection system, which is capable of rapidly depositing a small, controlled quantity of a wide variety of solid impurities into the confinement volume, has been installed and successfully tested. AXUV photodiode arrays equipped with optional soft x-ray filters have also been installed on the machine. The arrays will take time-resolved measurements of the impurity radiation, which will be inverted into radial profile and then interpreted using the transport code, STRAHL and atomic data from ADAS to determine the transport coefficients within the paradigm of a diffusivity and convective velocity. Details of the system and first results will be presented along with PENTA calculations of the neoclassical predicted impurity transport Work supported by US DOE contracts DE-FG02-01ER54615 and DE-FG02-93ER54222.

  8. Changes in permeability of the Nojima fault damage zone inferred from repeated water injection experiments

    NASA Astrophysics Data System (ADS)

    Kitagawa, Yuichi; Kano, Yasuyuki

    2016-11-01

    In 1995, the Hyogoken-Nanbu earthquake ( M 7.3) ruptured the Nojima fault, Awaji Island, central Japan. To investigate the recovery process of a fault zone after a large earthquake, repeated water injection experiments have been conducted every few years in an 1800-m-long borehole near the Nojima fault since 1997. In addition, the groundwater discharge rate and pressure have been observed in an 800-m borehole. From the resulting data, the macroscopic permeability of the fault fracture zone was estimated to range roughly from 1 × 10-6 to 2 × 10-6 m/s. The macroscopic permeability of the fault fracture zone decreased until 2003, and then, it stabilized or increased slightly through 2006. These changes in permeability indicate that the fault fracture zone stabilized within 8 years after the occurrence of the earthquake.[Figure not available: see fulltext.

  9. Object-based inversion of crosswell radar tomography data to monitor vegetable oil injection experiments

    USGS Publications Warehouse

    Lane, Jr., John W.; Day-Lewis, Frederick D.; Versteeg, Roelof J.; Casey, Clifton C.

    2004-01-01

    Crosswell radar methods can be used to dynamically image ground-water flow and mass transport associated with tracer tests, hydraulic tests, and natural physical processes, for improved characterization of preferential flow paths and complex aquifer heterogeneity. Unfortunately, because the raypath coverage of the interwell region is limited by the borehole geometry, the tomographic inverse problem is typically underdetermined, and tomograms may contain artifacts such as spurious blurring or streaking that confuse interpretation.We implement object-based inversion (using a constrained, non-linear, least-squares algorithm) to improve results from pixel-based inversion approaches that utilize regularization criteria, such as damping or smoothness. Our approach requires pre- and post-injection travel-time data. Parameterization of the image plane comprises a small number of objects rather than a large number of pixels, resulting in an overdetermined problem that reduces the need for prior information. The nature and geometry of the objects are based on hydrologic insight into aquifer characteristics, the nature of the experiment, and the planned use of the geophysical results.The object-based inversion is demonstrated using synthetic and crosswell radar field data acquired during vegetable-oil injection experiments at a site in Fridley, Minnesota. The region where oil has displaced ground water is discretized as a stack of rectangles of variable horizontal extents. The inversion provides the geometry of the affected region and an estimate of the radar slowness change for each rectangle. Applying petrophysical models to these results and porosity from neutron logs, we estimate the vegetable-oil emulsion saturation in various layers.Using synthetic- and field-data examples, object-based inversion is shown to be an effective strategy for inverting crosswell radar tomography data acquired to monitor the emplacement of vegetable-oil emulsions. A principal advantage of

  10. One, Two, and Three Dimensional Simulations of Laboratory Beam-Injection Experiments

    NASA Astrophysics Data System (ADS)

    Goldman, M. V.; Newman, D. L.; Oppenheim, M. M.; Wong, A. Y.; Cheung, P. Y.

    2000-10-01

    We present the results of three-dimensional fully kinetic simulations of UCLA laboratory experiments,(A. Y. Wong and P. Y. Cheung, Phys. Rev. Lett.), 52, 1222 (1984) which were the first experiments to show Langmuir-wave collapse in a beam-driven plasma. Our massively-parallel particle-in-cell (PIC) simulations model the continuous injection of a fast (v_b=20v_e), cold (Δ vb = Δ v_e), and weak (n_b/n_0=0.005) beam, which is comparable to that used in the laboratory experiments. By comparing the results of 1-D, 2-D, and 3-D simulations with one another and with laboratory measurements, we address the role of dimensionality on key phases of the evolution of beam-driven Langmuir turbulence. Of particular interest are the localization of intense Langmuir wave packets and the subsequent deepening of quasineutral density depressions due to the hydrodynamic response of ions to the ponderomotive force of the localized Langmuir waves. A variety of visualization tools will be employed in the analysis of the three-dimensional turbulence.

  11. A mathematical model to predict the size of the pellets formed in freeze pelletization techniques: parameters affecting pellet size.

    PubMed

    Cheboyina, Sreekhar; O'Haver, John; Wyandt, Christy M

    2006-01-01

    A mathematical model was developed based on the theory of drop formation to predict the size of the pellets formed in the freeze pelletization process. Further the model was validated by studying the effect of various parameters on the pellet size such as viscosity of the pellet forming and column liquids, surface/interfacial tension, density difference between pellet forming and column liquids; size, shape, and material of construction of the needle tips and temperatures maintained in the columns. In this study, pellets were prepared from different matrices including polyethylene glycols and waxes. The column liquids studied were silicone oils and aqueous glycerol solutions. The surface/interfacial tension, density difference between pellet forming and column liquids and needle tip size were found to be the most important factors affecting pellet size. The viscosity of the column liquid was not found to significantly affect the size of the pellets. The size of the pellets was also not affected by the pellet forming liquids of low viscosities. An increase in the initial column temperature slightly decreased the pellet size. The mathematical model developed was found to successfully predict the size of the pellets with an average error of 3.32% for different matrices that were studied.

  12. An analysis of the SCEX 3 ionospheric electron beam injection experiment

    SciTech Connect

    Goerke, R.T.

    1992-01-01

    The SCEX 3 experiment (Several Compatible EXperiments using a rocket-borne accelerator) was carried to ionospheric altitudes (375 km) by a Black Brant 11 rocket on February 1, 1990. The experiment was launched from Poker Flat Research Range (65.1 degree N, 147.5 degree W) at 1207 UT. The payload split into two parts (hereafter forward and aft payloads) 116 seconds after launch. The aft payload carried two electron accelerators as well as several diagnostic instruments. The forward payload was ejected at an angle of 6 degree with the magnetic field in a northwesterly direction. This payload carried a multiband plasma wave receiver and various particle detectors to make in situ measurements of the Beam Plasma Interaction (BPI) region. Two Throw Away Detectors (TAD's 1 and 2) were also ejected from the aft payload in the east and west directions respectively. TAD 1 also carried a multiband plasma wave receiver. Preceding the launch an auroral arch along the southern boundary of a diffuse auroral patch suddenly brightened, split into two separate arcs and moved to a position north of the rocket's trajectory. SCEX 3 was launched into an active breakup aurora consisting of tall rays and diffuse patches. The purpose of this experiment were (1) to observe injected electrons reflected from the naturally occurring parallel electric field structures which are thought to accelerate the auroral electron, (2) to observe a variety of plasma effects caused by the artificial electron beam and the associated spacecraft charging, and (3) study the natural phenomena associated with auroral activity. This work is a summary of the interesting observations made by the SCEX 3 experiment. These observations include VHF emissions produced by the electron beam via the Beam Plasma Discharge (BPD), Diffuse resonance emissions by the hot plasma region surrounding the electron beam and auroral Z-mode emissions.

  13. Transport and micro-instability analysis of JET H-mode plasma during pellet fueling

    NASA Astrophysics Data System (ADS)

    Klaywittaphat, P.; Onjun, T.

    2017-02-01

    Transport and micro-instability analysis in a JET H-mode plasma discharge 53212 during the pellet fueling operation is carried out using the BALDUR integrated predictive modeling code with a combination of the NCLASS neoclassical transport model and an anomalous core transport model (either Mixed B/gB or MMM95 model). In this work, the evolution of plasma current, plasma density and temperature profiles is carried out and, consequently, the plasma’s behaviors during the pellet operation can be observed. The NGS pellet model with the Grad-B drift effect included is used to describe pellet ablation and its behaviors when a pellet is launched into hot plasma. The simulation shows that after each pellet enters the plasma, there is a strong perturbation on the plasma causing a sudden change of both thermal and particle profiles, as well as the thermal and particle transports. For the simulation using MMM95 transport model, the change of both thermal and particle transports during pellet injection are found to be dominated by the transport due to the resistive ballooning modes due to the increase of collisionality and resistivity near the plasma edge. For the simulation based on mixed B/gB transport model, it is found that the change of transport during the pellet injection is dominated by the Bohm term. Micro-instability analysis of the plasma during the time of pellet operation is also carried out for the simulations based on MMM95 transport model. It is found that the ion temperature gradient mode is destabilized due to an increase of temperature gradient in the pellet effective region, while the trapped electron mode is stabilized due to an increase of collisionality in that region.

  14. Formation and sustainment of a very low aspect ratio tokamak using coaxial helicity injection (the Helicity Injected Torus (HIT) experiment)

    SciTech Connect

    Jarboe, T.R.; Nelson, B.A.

    1992-01-01

    In the paper we will detail the progress of the HIT experiment construction, including the following components: preliminary data and interpretation; diagnostic systems; vacuum vessel and pumping system; helicity source and power supplies; toroidal field coil and power supply; data acquisition system; collaboration with general atomics, with a brief summary given on each.

  15. High density operation in H mode discharges by inboard launch pellet refuelling

    NASA Astrophysics Data System (ADS)

    Lang, P. T.; Gafert, J.; Gruber, O.; Kaufmann, M.; Lorenz, A.; Maraschek, M.; Mertens, V.; Neuhauser, J.; Salzmann, H.; ASDEX Upgrade Team

    2000-02-01

    Operating a tokamak at plasma densities near the empirical Greenwald limit bar neGw in H mode could yield significant advantages for a fusion reactor. Trying to avoid the strong confinement degradation observed with gas puff refuelling, pellet injection from the magnetic high field side was applied. Sufficient pellet particle flux was supplied to achieve persistent density rampup and to enable density control in H mode at a level beyond bar neGw for the first time. The pellet induced density increase decays in a fast phase with τ = 10 ms until about half of the latest pellet inventory remains, and decays thereafter to the base density on the particle confinement timescale with τ = 120 ms. The fast decay is the result of strong ELM events following each injected pellet, accompanied by a loss of energy, causing a transient reduction of the plasma energy content by convective heat flux. Recovery of the plasma energy after the ELM sequence takes place with τ = 25 ms, enabling transient operation at appropriately high densities without significant confinement degradation. To reach this scenario, however, confinement degradation caused by other factors must be inhibited. Other factors causing confinement degradation were found to be the increase of neutral gas pressure by pellet born gas puff at insufficient pumping speed or the occurrence of neoclassical tearing modes triggered by pellets when the temperatures close to rational surfaces were reduced too strongly.

  16. Experiments and analysis of drainage displacement processes relevant to carbon dioxide injection.

    PubMed

    Aryana, Saman A; Kovscek, Anthony R

    2012-12-01

    The motivation for this work is a dramatically improved understanding of the fluid mechanics of drainage processes with applications such as CO_{2} storage in saline aquifers and water-alternating-gas injection as an enhanced oil recovery method. In this paper we present in situ distributions of wetting and nonwetting fluids obtained during core-scale two-phase immiscible drainage experiments. The ratio of the viscosity of the resident fluid to that of the invading fluid varies across a range of 0.43 to 150. Saturation distributions observed during dynamic displacement experiments are surprisingly smooth and do not display only one or a few dominant fingers, contrary to the indications of the current literature. The analysis of the saturation distribution using the fractal dimensions of the dynamic three-dimensional saturation distributions suggests that the constitutive relationships for porous media, namely, the relative permeability functions, are history dependent. Accordingly, it is suggested that the nonlinear, unstable flow regime is the regime where efforts to improve physical understanding must be focused.

  17. In Silico and In Vivo Experiments Reveal M-CSF Injections Accelerate Regeneration Following Muscle Laceration.

    PubMed

    Martin, Kyle S; Kegelman, Christopher D; Virgilio, Kelley M; Passipieri, Julianna A; Christ, George J; Blemker, Silvia S; Peirce, Shayn M

    2017-03-01

    Numerous studies have pharmacologically modulated the muscle milieu in the hopes of promoting muscle regeneration; however, the timing and duration of these interventions are difficult to determine. This study utilized a combination of in silico and in vivo experiments to investigate how inflammation manipulation improves muscle recovery following injury. First, we measured macrophage populations following laceration injury in the rat tibialis anterior (TA). Then we calibrated an agent-based model (ABM) of muscle injury to mimic the observed inflammation profiles. The calibrated ABM was used to simulate macrophage and satellite stem cell (SC) dynamics, and suggested that delivering macrophage colony stimulating factor (M-CSF) prior to injury would promote SC-mediated injury recovery. Next, we performed an experiment wherein 1 day prior to injury, we injected M-CSF into the rat TA muscle. M-CSF increased the number of macrophages during the first 4 days post-injury. Furthermore, treated muscles experienced a swifter increase in the appearance of PAX7(+) SCs and regenerating muscle fibers. Our study suggests that computational models of muscle injury provide novel insights into cellular dynamics during regeneration, and further, that pharmacologically altering inflammation dynamics prior to injury can accelerate the muscle regeneration process.

  18. Confinement of high-density pellet-fueled discharges in TFTR

    SciTech Connect

    Milora, S.L.; Schmidt, G.L.; Bell, M.G.; Bitter, M.; Bush, C.E.; Combs, S.K.; England, A.; Fredrickson, E.; Goldston, R.J.; Grek, B.

    1986-01-01

    TFTR pellet injection results reported by Schmidt have been extended to higher density and ntau in plasmas limited by a graphite inner-wall belt limiter. Increased pellet penetration and larger density increases were achieved by operation at reduced plasma current (1.6 MA), minor radius (70 cm), and major radius (235 cm). Under these conditions, beam heating results have been extended to 7 MW.

  19. Particle simulation of runaway electrons in rippled tokamaks with pellet suppression effects

    NASA Astrophysics Data System (ADS)

    Spong, D. A.; Carbajal Gomez, L.; Del-Castillo-Negrete, D.; Baylor, L.; Seal, S.

    2016-10-01

    Runaway electrons are of significant concern for large tokamak devices both due to gradual acceleration by the Ohmic heating field and the more rapid acceleration and avalanche production that can occur during major disruptions. We have developed a simulation model (KORCGC) that follows large number of runaway guiding center (GC) orbits, taking into account Coulomb collisions, impurities, synchrotron radiation, rippled (3D) fields, and electric field acceleration, including inductive effects. Applications to pellet suppression experiments have been made and show similar effects (current/energy decay rates) as the observations. The model uses a hybrid (MPI/OpenMP) design and shows excellent parallel scaling. The energy parameters of runaway pellet suppression and formation fit within the limits of the GC approximation and the longer timesteps allowed by GC facilitate modeling over relevant timescales. Simulations of impurity injection dissipation experiments on DIIID and ITER will be discussed. Research sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U. S. Department of Energy and by U.S. Department of Energy, Office of Science Contract No. DE-AC05-00OR2.

  20. Recent high-speed ballistics experiments at ORNL

    SciTech Connect

    Combs, S.K.; Gouge, M.J.; Baylor, L.R.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Milora, S.L.; Qualls, A.L.

    1994-12-31

    Oak Ridge National Laboratory (ORNL) has been developing pellet injectors for plasma fueling experiments on magnetic confinement devices for almost 20 years. With these devices, pellets (1 to 8 mm in diameter) composed of hydrogen isotopes are formed (at temperatures <20 K) and typically accelerated to speeds of {approximately} 1.0 to 2.0 km/s for injection into plasmas of experimental fusion devices. A variety of pellet injector designs have been developed at ORNL, including repeating pneumatic injectors (single- and multiple-barrel light gas guns) that can inject up to hundreds of pellets for long-pulse plasma operation. The repeating pneumatic injectors are of particular importance because long-pulse fueling is required for present large experimental fusion devices, with steady-state operation the objective for future fusion reactors. In this paper, recent advancements in the development of repeating pneumatic injectors are described, including (1) a small-bore (1.8-mm), high-firing-rate (10-Hz) version of a single-stage light gas gun; (2) a repeating single-stage light gas gun for 8-mm-diam tritium pellets; (3) a repeating two-stage light gas gun for operation at higher pellet velocities; and (4) a steady-state hydrogen extruder feed system.

  1. Treatment readiness, attitudes toward, and experiences with methadone and buprenorphine maintenance therapy among people who inject drugs in Malaysia

    PubMed Central

    Vijay, Aishwarya; Bazazi, Alexander R.; Yee, Ilias; Kamarulzaman, Adeeba; Altice, Frederick L.

    2016-01-01

    Background Little is known about attitudes toward and experiences with opioid maintenance therapy (OMT) among people who inject drugs in Malaysia, a country where people who inject drugs comprise 1.3% of the adult population. Methods In 2010, 460 people who inject drugs in Greater Kuala Lumpur, Malaysia were surveyed to evaluate attitudes toward and experience with OMT and treatment readiness. Attitudes towards OMT with both methadone and buprenorphine were assessed using an opinions scale. Multivariable linear regression was used to assess correlates of treatment readiness, measured with the 19-item Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES). Results All 460 participants used opioids and nearly all (99.1%) met criteria for opioid dependence. Few had had previous experience with methadone (9.3%) or buprenorphine (12.6%) maintenance therapy, yet many had used methadone (55.2%) or buprenorphine (51.7%) outside of treatment settings. Fifteen percent had injected buprenorphine in the past month, and of the few that were currently receiving buprenorphine maintenance therapy, almost all were injecting it. The majority of subjects exhibited a moderate level of treatment readiness and a preference for methadone over buprenorphine. Those with low treatment readiness scores were more likely to have previous experience with compulsory drug detention centers (p<0.01), needle/syringe exchange programs (p<0.005), or be of Indian ethnicity (p<0.001). Past use of methadone (p<0.01), older age (p<0.001), stress symptom severity (p<0.001), and sharing of needles or syringes (p<0.05) were associated with higher treatment readiness scores. Conclusion There are suboptimal levels of OMT experience among people who inject drugs that may be improved by addressing factors that influence patient attitudes. Those individuals with moderate treatment readiness may be targeted by brief motivational and cognitive interventions in primary care, prisons or OMT clinics

  2. Phosphorus recovery using pelletized adsorptive materials ...

    EPA Pesticide Factsheets

    Phosphorous (P) is one of the essential nutrients for growth and is generally the most limiting nutrient since, it cannot be fixed from the atmosphere. Methods for recovering phosphorous from water systems already exist, but advances are being made to find a more economic, efficient, effective and easy to use method that can allow for reuse of the recovered P. One area of study is in adsorption, which involves finding the best material for adsorption of phosphorous from water and for releasing it back into the environment through desorption or leaching. The goal of this research was to first optimize the capacity for a pelletized adsorptive material that was synthesized with varying amounts of a binder material from 0-20 % and then to study recovering the phosphate for reuse. The pelletized materials were studied through kinetics experiments as well as isotherm experiments to gain insight into the adsorption capacity and mechanism. Following successful adsorption, a simple leaching study was conducted to see how much phosphate would be released back into water without any added desorption aid. Desorption was then studied by changing the pH of solution. Presenting my thesis work with a poster at ACS.

  3. Ultrasound-guided injection for the biceps brachii tendinitis: results and experience.

    PubMed

    Zhang, Jingwei; Ebraheim, Nabil; Lause, Gregory E

    2011-05-01

    The purpose of this study was to identify the results of ultrasound-guided injection of corticosteroid for biceps brachii tendinitis. In this randomized and prospective study, we evaluated 45 patients who were treated by free-hand injection without ultrasound guidance (group A) and 53 patients who were treated by ultrasound-guided injection (group B). The mean age was 47 y (range, 28 to 72). The average follow-up was 33 weeks (range, 24 to 56). The visual analog scale score decreased from 7.1 ± 2.3 before injection to 4.2 ± 3.1 at follow-up in group A and from 6.9 ± 2.6 to 2.1 ± 1.9 in group B (p < 0.05). The Constant-Murley score improved from 31.4 ± 11.6 before injection to 73.5 ± 19.2 at follow-up in group A and from 32.5 ± 14.7 to 85.5 ± 10.3 (p < 0.01). The ultrasound-guided injection therefore demonstrated a statistically significantly greater degree of pain relief. However, the outcome of injection was not satisfactory for the patients who demonstrated severely frayed tendons at arthroscopy. There were no complications related to the injection in both groups. Corticosteroid injection under ultrasound guidance is a safe and well-tolerated procedure with a satisfactory rate of symptom relief in patients with biceps brachii tendinitis.

  4. Method for producing pellets for use in a cryoblasting process

    DOEpatents

    Foster, Christopher A.; Fisher, Paul W.

    1997-01-01

    A cryoblasting process having a centrifugal accelerator for accelerating frozen pellets of argon or carbon dioxide toward a target area utilizes an accelerator throw wheel designed to induce, during operation, the creation of a low-friction gas bearing within internal passages of the wheel which would otherwise retard acceleration of the pellets as they move through the passages. An associated system and method for removing paint from a surface with cryoblasting techniques involves the treating, such as a preheating, of the painted surface to soften the paint prior to the impacting of frozen pellets thereagainst to increase the rate of paint removal. A system and method for producing large quantities of frozen pellets from a liquid material, such as liquid argon or carbon dioxide, for use in a cryoblasting process utilizes a chamber into which the liquid material is introduced in the form of a jet which disintegrates into droplets. A non-condensible gas, such as inert helium or air, is injected into the chamber at a controlled rate so that the droplets freeze into bodies of relatively high density.

  5. Electron beam injection experiments - The beam-plasma discharge at low pressures and magnetic field strengths

    NASA Technical Reports Server (NTRS)

    Bernstein, W.; Leinbach, H.; Kellogg, P.; Monson, S.; Hallinan, T.; Garriott, O. K.; Konradi, A.; Mccoy, J.; Daly, P.; Baker, B.

    1978-01-01

    The paper describes electron beam injection experiments which clarify observational results obtained in rocket flights. A column of enhanced density plasma, exceeding the density expected from ionization by primary beam electrons, was observed in a large vacuum system at low magnetic fields (1 to 1.5 G) and low ambient pressures (10 to the minus 6 to 10 to the minus 5 torr). The peak luminosity of the discharge was about 10 times that of the beam alone, and the radius increased by a factor of three. In the absence of the discharge, RF emission is observed at 1.1 to 1.2 times the cyclotron frequency, and a strong band of RF noise with upper frequency cutoff at about the cyclotron frequency is observed in the discharge mode, along with higher frequency noise at or near the plasma frequency. The onset of the plasma discharge is critically dependent on beam current. The described results agree with observations obtained at much higher densities and magnetic fields in fusion research studies.

  6. Neutral Beam Injection System for the C-2W Field Reversed Configuration Experiment

    NASA Astrophysics Data System (ADS)

    Dunaevsky, Alexander; Ivanov, Alexander; Kolmogorov, Vyacheslav; Smirnov, Artem; Korepanov, Sergey; Binderbauer, Michl; TAE Team; BINP Team

    2016-10-01

    C-2U Field-Reversed Configuration (FRC) experiment proved substantial reduction in turbulence-driven losses via tangential neutral beam injection (NBI) coupled with electrically biased plasma guns at the plasma ends. Under such conditions, highly reproducible, advanced beam-driven FRCs were produced and sustained for times significantly longer (more than 5 ms) than all characteristic plasma decay times without beams. To further improve FRC sustainment and demonstrate the FRC ramp-up, the C-2U experimental device is undergoing a major upgrade. The upgrade, C-2W, will have a new NBI system producing a record total hydrogen beam power of 20 + MW in a 30ms pulse. The NBI system consists of eight positive-ion based injectors featuring flexible, modular design. Four out of eight NBI injectors have a capability to switch the beam energy during a shot from the initial 15 keV to 40 keV at a constant beam current. This feature allows to increase the beam energy and thereby optimize the beam-plasma coupling during the magnetic field ramp up. This presentation provides an overview of the C-2W NBI system, including the design of the switchable energy injectors, layout of the power supply system, and results of the prototype testing.

  7. Laboratory experiments in the argon plasma perturbed by injections of the electronegative gases

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao; Cao, Jin-xiang; Liu, Yu; Yu, Peng-cheng; Zhang, Zhong-kai

    2016-07-01

    In this study, laboratory observations of the perturbations of the magnetic field are reported due to the injection of attachment chemicals (CF4, SF6, and CO2) into argon plasmas. Besides the well-known electron density reduction, we also observed magnetic field perturbation in the experiment. The measured induced voltage B ˙ , which is taken as a proxy of the time-changing electromagnetic field, fluctuates in the boundary layer between the ambient plasmas and negative ions plasmas. Perturbations of the magnetic field were investigated by changing the ambient pressure and ratio of attachment chemicals. The measured B ˙ keeps increasing in these lower pressures; but it no longer increases as the ambient pressure higher than a threshold, e.g., for CF4, SF6, and CO2, the transition pressure is 6Pa, 5Pa and 4Pa, respectively. The magnitude of the B ˙ increase with the change of the ratio of release flow until at higher ratios, e.g., 40%. We transformed these time-sampled data into the frequency domain and found coherent modes with fundamental frequencies lying in the lower hybrid range. In addition, these coherent frequencies show a frequency drift with the increase of the contents of the negative ions. These modes were suggested as the magnetic component of electron-ion hybrid mode. This work has an important application in the study of artificially-created ionospheric depletion which is usually generated by releasing of attachment chemicals in the upper atmosphere.

  8. Experiences with Policing among People Who Inject Drugs in Bangkok, Thailand: A Qualitative Study

    PubMed Central

    Hayashi, Kanna; Small, Will; Csete, Joanne; Hattirat, Sattara; Kerr, Thomas

    2013-01-01

    Background Despite Thailand's commitment to treating people who use drugs as “patients” not “criminals,” Thai authorities continue to emphasize criminal law enforcement for drug control. In 2003, Thailand's drug war received international criticism due to extensive human rights violations. However, few studies have since investigated the impact of policing on drug-using populations. Therefore, we sought to examine experiences with policing among people who inject drugs (PWID) in Bangkok, Thailand, between 2008 and 2012. Methods and Findings Between July 2011 and June 2012, semi-structured, in-depth interviews were conducted with 42 community-recruited PWID participating in the Mitsampan Community Research Project in Bangkok. Interviews explored PWID's encounters with police during the past three years. Audio-recorded interviews were transcribed verbatim, and a thematic analysis was conducted to document the character of PWID's experiences with police. Respondents indicated that policing activities had noticeably intensified since rapid urine toxicology screening became available to police. Respondents reported various forms of police misconduct, including false accusations, coercion of confessions, excessive use of force, and extortion of money. However, respondents were reluctant to report misconduct to the authorities in the face of social and structural barriers to seeking justice. Respondents' strategies to avoid police impeded access to health care and facilitated transitions towards the misuse of prescribed pharmaceuticals. The study's limitations relate to the transferability of the findings, including the potential biases associated with the small convenience sample. Conclusions This study suggests that policing in Bangkok has involved injustices, human rights abuses, and corruption, and policing practices in this setting appeared to have increased PWID's vulnerability to poor health through various pathways. Novel to this study are findings

  9. Solidification and Acceleration of Large Cryogenic Pellets Relevant for Plasma Disruption Mitigation

    SciTech Connect

    Combs, Stephen Kirk; Meitner, S. J.; Gebhart, T. E.; Baylor, Larry R.; Caughman, John B.; Fehling, Dan T.; Foust, Charles R.; Ha, Tam T.; Lyttle, Mark S.; Fisher, J. T.; Younkin, T. R.

    2016-01-01

    The technology for producing, accelerating, and shattering large pellets (before injection into plasmas) for disruption mitigation has been under development at the Oak Ridge National Laboratory for several years, including a system on DIII-D that has been used to provide some significant experimental results. The original proof-of-principle testing was carried out using a pipe gun injector cooled by a cryogenic refrig- erator (temperatures ~8-20 K) and equipped with a stainless steel tube to produce 16.5-mm pellets composed of either pure D2, pure Ne, or a dual layer with a thin outer shell of D2 and core of Ne. Recently, significant progress has been made in the laboratory using that same pipe gun and a new injector that is an ITER test apparatus cooled with liquid helium. The new injector operates at ~5-8 K, which is similar to temperatures expected with cooling provided by the flow of supercritical helium on ITER. An alternative technique for producing/solidifying large pellets directly from a premixed gas has now been successfully tested in the laboratory. Also, two additional pellet sizes have been tested recently (nominal 24.4 and 34.0 mm diameters). With larger pellets, the number of injectors required for ITER disruption mitigation can be reduced, resulting in less cost and a smaller footprint for the hardware. An attractive option is longer pellets, and 24.4-mm pellets with a length/diameter ratio of ~3 have been successfully tested. Since pellet speed is the key parameter in determining the response time of a shattered pellet system to a plasma disruption event, recent tests have concentrated on documenting the speeds with different hardware configurations and operating parameters; speeds of ~100-800 m/s have been recorded. The data and results from laboratory testing are presented and discussed, and a simple model for the pellet solidification process is described.

  10. Solidification and Acceleration of Large Cryogenic Pellets Relevant for Plasma Disruption Mitigation

    DOE PAGES

    Combs, Stephen Kirk; Meitner, S. J.; Gebhart, T. E.; ...

    2016-01-01

    The technology for producing, accelerating, and shattering large pellets (before injection into plasmas) for disruption mitigation has been under development at the Oak Ridge National Laboratory for several years, including a system on DIII-D that has been used to provide some significant experimental results. The original proof-of-principle testing was carried out using a pipe gun injector cooled by a cryogenic refrig- erator (temperatures ~8-20 K) and equipped with a stainless steel tube to produce 16.5-mm pellets composed of either pure D2, pure Ne, or a dual layer with a thin outer shell of D2 and core of Ne. Recently, significantmore » progress has been made in the laboratory using that same pipe gun and a new injector that is an ITER test apparatus cooled with liquid helium. The new injector operates at ~5-8 K, which is similar to temperatures expected with cooling provided by the flow of supercritical helium on ITER. An alternative technique for producing/solidifying large pellets directly from a premixed gas has now been successfully tested in the laboratory. Also, two additional pellet sizes have been tested recently (nominal 24.4 and 34.0 mm diameters). With larger pellets, the number of injectors required for ITER disruption mitigation can be reduced, resulting in less cost and a smaller footprint for the hardware. An attractive option is longer pellets, and 24.4-mm pellets with a length/diameter ratio of ~3 have been successfully tested. Since pellet speed is the key parameter in determining the response time of a shattered pellet system to a plasma disruption event, recent tests have concentrated on documenting the speeds with different hardware configurations and operating parameters; speeds of ~100-800 m/s have been recorded. The data and results from laboratory testing are presented and discussed, and a simple model for the pellet solidification process is described.« less

  11. Validating An Analytic Completeness Model for Kepler Target Stars Based on Flux-level Transit Injection Experiments

    NASA Astrophysics Data System (ADS)

    Catanzarite, Joseph; Burke, Christopher J.; Li, Jie; Seader, Shawn; Haas, Michael R.; Batalha, Natalie; Henze, Christopher; Christiansen, Jessie; Kepler Project, NASA Advanced Supercomputing Division

    2016-06-01

    The Kepler Mission is developing an Analytic Completeness Model (ACM) to estimate detection completeness contours as a function of exoplanet radius and period for each target star. Accurate completeness contours are necessary for robust estimation of exoplanet occurrence rates.The main components of the ACM for a target star are: detection efficiency as a function of SNR, the window function (WF) and the one-sigma depth function (OSDF). (Ref. Burke et al. 2015). The WF captures the falloff in transit detection probability at long periods that is determined by the observation window (the duration over which the target star has been observed). The OSDF is the transit depth (in parts per million) that yields SNR of unity for the full transit train. It is a function of period, and accounts for the time-varying properties of the noise and for missing or deweighted data.We are performing flux-level transit injection (FLTI) experiments on selected Kepler target stars with the goal of refining and validating the ACM. “Flux-level” injection machinery inserts exoplanet transit signatures directly into the flux time series, as opposed to “pixel-level” injection, which inserts transit signatures into the individual pixels using the pixel response function. See Jie Li's poster: ID #2493668, "Flux-level transit injection experiments with the NASA Pleiades Supercomputer" for details, including performance statistics.Since FLTI is affordable for only a small subset of the Kepler targets, the ACM is designed to apply to most Kepler target stars. We validate this model using “deep” FLTI experiments, with ~500,000 injection realizations on each of a small number of targets and “shallow” FLTI experiments with ~2000 injection realizations on each of many targets. From the results of these experiments, we identify anomalous targets, model their behavior and refine the ACM accordingly.In this presentation, we discuss progress in validating and refining the ACM, and we

  12. Thermionic plasma injection for the Lockheed Martin T4 Compact Fusion Reactor experiment

    NASA Astrophysics Data System (ADS)

    Heinrich, Jonathon

    2015-11-01

    Lockheed Martin's Compact Fusion Reactor (CFR) concept relies on diamagnetic confinement in a magnetically encapsulated linear ring cusp geometry. Plasma injection into cusp field configurations requires careful deliberation. Previous work has shown that axial injection via a plasma gun is capable of achieving high-beta conditions in cusp configurations. We present a pulsed, high power thermionic plasma source and the associated magnetic field topology for plasma injection into the caulked-cusp magnetic field. The resulting plasma fueling and cross-field diffusion is discussed.

  13. Pitch angle scattering by triggered emissions from the Siple Station wave injection experiment

    NASA Astrophysics Data System (ADS)

    Harid, V.; Golkowski, M.; Bell, T. F.; Cohen, M.; Inan, U. S.

    2012-12-01

    Nonlinear amplification of whistler mode waves in the Earth's magnetosphere , due to gyroresonance with energetic electrons, also known as the phenomena of VLF triggered emissions, has been investigated extensively with analytical formulations, experimental observations and computer simulations. However, the pitch angle scattering of typical triggered emission waveforms has not been specifically considered. Most authors consider particle scattering either in the presence of a monochromatic constant amplitude wave or a broadband incoherent but time-frequency homogenous emission. Although investigation of these two limiting cases has provided valuable insight into radiation belt dynamics, a large class of waves including triggered emissions and chorus do not fall under either of the two descriptions. The inherent symmetry of a constant amplitude monochromatic wave around the equator results in non-cumulative pitch angle change for a large population of electrons. Wave amplification generated during linear and nonlinear growth result in wave gradients that can have a more significant effect on particle pitch angle and energy. In addition, coherent frequency changing signals are capable of shifting the cyclotron resonance condition and significantly perturbing particle trajectories from their adiabatic motion. The wave-injection experiment at Siple Station, Antarctica was designed to study wave growth and triggering processes in the magnetosphere. Amplified signals from Siple Station often show both wave gradients as well advances in phase and frequency. Using a numerical test-particle simulation, we model the effect of typical Siple Station signals on pitch angle scattering and particle precipitation. Results show that triggered emission type wave forms are more efficient in producing large pitch angle changes in resonant particles.

  14. Design of a field experiment for injection of natural colloids in a sandy coastal plain aquifer, Belle W. Baruch Forest Science Institute, Georgetown, South Carolina

    SciTech Connect

    Toran, L.E.; McCarthy, J.F. ); Williams, T.M. . Belle W. Baruch Forest Science Inst.)

    1990-06-01

    This report summarizes the design of field injection experiments that constitute one task in the larger project described in the report Experiments Using Natural Organics.'' In the experiment, we plan to inject a large volume of colloidal organic matter (COM) into a sandy, unconsolidated coastal aquifer and observe the migration of COM into the groundwater flow system. The report provides a brief overview of the research project, including hypotheses to be tested; describes the purpose of the field injection experiments; summarizes the site characterization preliminary to the experiments; and explains the design of the experiments. 11 figs., 5 tabs.

  15. Recent experience with and future directions of contraceptive implants and injectable contraceptives.

    PubMed

    Alvarez-Sanchez, F; Brache, V; Faundes, A

    1993-12-01

    Subdermal implantable contraception has been the most important addition to contraceptive technology in the past 2 decades. The Norplant system is only the first of a new family of long acting methods of high effectiveness, high acceptability, and prompt reversibility. The main advantage of the second generation implant systems, to be available soon, is the reduction in the number of implants, which greatly facilitates insertion and removal. However, great improvement in bleeding control is not to be expected. Large and carefully designed epidemiological studies have contributed to clear the main objections to the US Food and Drug Administration (FDA) approval of depot medroxyprogesterone acetate (DMPA) as an injectable contraceptive. New progestin-only, long acting injectables are being tested, but significant improvements over existing methods are difficult to foresee, although every alternative is welcome. Monthly combined injectables have been in great demand, at least in China and Latin America, because of better bleeding control. Improved combined monthly injectables, less estrogenic and more progestin dominated, have been developed and are being introduced in several countries and should soon replace the old monthly injectables. Contraceptive implants and injectables have shown to be an important addition to the contraceptive options available to women throughout both the developing and developed world.

  16. Clinical experience with repository corticotropin injection in patients with multiple sclerosis experiencing mood changes with intravenous methylprednisolone: a case series

    PubMed Central

    Murray, Stacey; Woo, Andrew

    2015-01-01

    The elevated prevalence of neuropsychiatric symptoms and disorders among patients with multiple sclerosis (MS) is well recognized, as are potential neuropsychiatric side effects of treatment with corticosteroids. Both methylprednisolone (MP) and repository corticotropin injection (HP Acthar® gel) have demonstrated efficacy in reducing short-term disability after exacerbations of MS. Although historical data are limited, repository corticotropin injection has not generally been associated with detrimental neuropsychiatric effects. We describe six cases of patients with relapsing-remitting MS who had previously experienced detrimental mood changes with MP treatment. Some of these patients had previous histories of mood disorders or other neuropsychiatric symptoms prior to MS diagnosis. All six patients were subsequently treated with repository corticotropin injection for MS exacerbations and each demonstrated improvements in MS symptoms. This clinical experience suggests that repository corticotropin injection should be considered as an alternative for patients who do not tolerate corticosteroids or have difficulties associated with intravenous medication. Furthermore, the rate of neuropsychiatric side effects observed in these patients was low. These observations support repository corticotropin injection as a viable alternative for the treatment of acute exacerbations of MS, particularly in patients who have a history of neuropsychiatric disorders or symptoms either independently or in response to MP treatment. In reviewing both the published data and our own clinical experience regarding potential neuropsychiatric adverse events with treatment for MS exacerbations, we hope to stimulate further research into the potential efficacy and safety of repository corticotropin injection among patients with some form of neuropsychiatric complications that must be considered when establishing a treatment plan for MS. PMID:27134674

  17. Prediction of the mechanical properties of zeolite pellets for aerospace molecular decontamination applications

    PubMed Central

    Rioland, Guillaume; Faye, Delphine; Patarin, Joël

    2016-01-01

    Zeolite pellets containing 5 wt % of binder (methylcellulose or sodium metasilicate) were formed with a hydraulic press. This paper describes a mathematical model to predict the mechanical properties (uniaxial and diametric compression) of these pellets for arbitrary dimensions (height and diameter) using a design of experiments (DOE) methodology. A second-degree polynomial equation including interactions was used to approximate the experimental results. This leads to an empirical model for the estimation of the mechanical properties of zeolite pellets with 5 wt % of binder. The model was verified by additional experimental tests including pellets of different dimensions created with different applied pressures. The optimum dimensions were found to be a diameter of 10–23 mm, a height of 1–3.5 mm and an applied pressure higher than 200 MPa. These pellets are promising for technological uses in molecular decontamination for aerospace-based applications. PMID:28144526

  18. Prediction of the mechanical properties of zeolite pellets for aerospace molecular decontamination applications.

    PubMed

    Rioland, Guillaume; Dutournié, Patrick; Faye, Delphine; Daou, T Jean; Patarin, Joël

    2016-01-01

    Zeolite pellets containing 5 wt % of binder (methylcellulose or sodium metasilicate) were formed with a hydraulic press. This paper describes a mathematical model to predict the mechanical properties (uniaxial and diametric compression) of these pellets for arbitrary dimensions (height and diameter) using a design of experiments (DOE) methodology. A second-degree polynomial equation including interactions was used to approximate the experimental results. This leads to an empirical model for the estimation of the mechanical properties of zeolite pellets with 5 wt % of binder. The model was verified by additional experimental tests including pellets of different dimensions created with different applied pressures. The optimum dimensions were found to be a diameter of 10-23 mm, a height of 1-3.5 mm and an applied pressure higher than 200 MPa. These pellets are promising for technological uses in molecular decontamination for aerospace-based applications.

  19. Effects of pellet diameter during and after lactation on feed intake of piglets pre- and postweaning.

    PubMed

    van den Brand, H; Wamsteeker, D; Oostindjer, M; van Enckevort, L C M; van der Poel, A F B; Kemp, B; Bolhuis, J E

    2014-09-01

    Effects of 2 pellet diameters for piglets pre- and postweaning on feed intake, BW, and feed-related behavior were studied in 3 experiments. In Exp. 1, 19 litters were provided with pellets of 2 and 12 mm in diameter in a choice-feeding setup from d 4 of lactation onward. From d 4 to 18, piglets preferred the 12-mm diameter pellet over the 2-mm diameter pellet (519 vs. 168 g/pen; P < 0.001). In Exp. 2, 39 litters were provided with creep feed of either 2- or 10-mm diameter pellets. Feed intake from d 3 to 17 was higher in litters provided the 10-mm diameter pellet than the 2-mm diameter pellet (1,752 vs. 1,101 g/pen; P < 0.001). Piglet BW at weaning did not differ between treatments. Treatment × day of lactation interactions were found for time spent eating, interest in eating, and time spent suckling. Time spent eating and interest in eating increased with time. This increase was lower in the litters provided with the 10-mm diameter pellet. Time spent suckling remained the same in litters provided with 2-mm diameter pellets but decreased in time in litters provided the 10-mm diameter pellets. Experiment 3 was set up as a 2 × 2 factorial design with pellet diameter both pre- and postweaning as factors. During lactation, 18 litters were provided creep feed of either 2 or 12 mm in pellet diameter. At weaning, each litter was split into 2 comparable half litters and each half litter was provided with feed of 2 or 12 mm in diameter. Feed intake was higher in the 12-mm diameter pellet litters than in the 2-mm ones from d 4 to 11 of lactation (P < 0.01). Pellet diameter provided after weaning did not affect BW gain or feed intake. Piglets provided the 12-mm diameter pellet before weaning, however, had a higher BW gain (2,060 vs. 2,606 g/pig; P = 0.003) and feed intake (2,772 vs. 3,173 g/pig; P = 0.04) and a lower feed conversion ratio (P = 0.03) between d 0 and 10 after weaning than piglets provided the 2-mm diameter pellet before weaning. Postweaning pellet diameter

  20. Pre-clinical results with Clariscan (NC100150 Injection); experience from different disease models.

    PubMed

    Bjørnerud, A; Johansson, L O; Ahlström, H K

    2001-05-01

    A superparamagnetic nanoparticle (NC100150 Injection) was investigated in two different animal models; renal perfusion in pigs and tumour imaging in mice. In the pig model, qualitative first-pass perfusion maps following a bolus injection of NC100150 Injection enabled good visualisation of hypoperfused regions of the renal cortex following partial ligation of the renal artery. High temporal resolution was found to be essential to accurately capture the first passage of the contrast agent through the kidney due to the very rapid blood flow in normal renal cortex. In the tumour model (LS174T cells implanted in nude mice), NC100150 Injection was found to cause a gradual (over 60 min) signal increase on T1-w images in part of the tumours which was attributed to contrast agent leakage from the vascular space to the extravascular space in areas of increased capillary permeability. This observation is consistent with previous reports on the molecular cut-off size for vascular extraction for this tumour cell line. The specific enhancement of tumour tissue suggest potential utility of NC100150 Injection as an angiogenesis marker.

  1. Active Flow Separation Control of a Stator Vane Using Surface Injection in a Multistage Compressor Experiment

    NASA Technical Reports Server (NTRS)

    Culley, Dennis E.; Bright, Michelle M.; Prahst, Patricia S.; Strazisar, Anthony J.

    2003-01-01

    Micro-flow control actuation embedded in a stator vane was used to successfully control separation and improve near stall performance in a multistage compressor rig at NASA Glenn. Using specially designed stator vanes configured with internal actuation to deliver pulsating air through slots along the suction surface, a research study was performed to identify performance benefits using this microflow control approach. Pressure profiles and unsteady pressure measurements along the blade surface and at the shroud provided a dynamic look at the compressor during microflow air injection. These pressure measurements lead to a tracking algorithm to identify the onset of separation. The testing included steady air injection at various slot locations along the vane. The research also examined the benefit of pulsed injection and actively controlled air injection along the stator vane. Two types of actuation schemes were studied, including an embedded actuator for on-blade control. Successful application of an online detection and flow control scheme will be discussed. Testing showed dramatic performance benefit for flow reattachment and subsequent improvement in diffusion through the use of pulsed controlled injection. The paper will discuss the experimental setup, the blade configurations, and preliminary CFD results which guided the slot location along the blade. The paper will also show the pressure profiles and unsteady pressure measurements used to track flow control enhancement, and will conclude with the tracking algorithm for adjusting the control.

  2. Incarceration, addiction and harm reduction: inmates experience injecting drugs in prison.

    PubMed

    Small, Will; Kain, S; Laliberte, Nancy; Schechter, Martin T; O'Shaughnessy, Michael V; Spittal, Patricia M

    2005-01-01

    Within Canadian prisons HIV/AIDS is becoming more common among inmates. While injection drug use in correctional facilities is documented to be a problem, qualitative research into the HIV risks faced by inmates is lacking. The goal of this research was to qualitatively examine HIV risk associated with injecting inside British Columbia prisons. A sample of 26 former male inmates who had recently used drugs within correctional facilities were recruited from a ongoing cohort study of injection drug users in Vancouver, Canada. Data for this study were collected through in-depth interviews conducted in 2001/2002. Analysis of these data involved identifying emergent themes and then exploring these central concepts in further interviews to confirm the accuracy of interpretation. The harms normally associated with drug addiction, and injection drug use are exacerbated in prison. Interpersonal relationships and the possession of exchangeable resources determine access to scarce syringes. The scarcity of syringes has resulted in patterns of sharing amongst large numbers of persons. Continual reuse of scarce syringes poses serious health hazards and bleach distribution is an inadequate solution. The findings of this study emphasize the need for effective harm reduction programs that provide an appropriate response to the problem of injection drug use among inmates.

  3. Heating system of pellet samples integrated with terahertz spectrometer

    NASA Astrophysics Data System (ADS)

    Sterczewski, L. A.; Grzelczak, M. P.; Plinski, E. F.

    2016-01-01

    This article describes automation of temperature-dependent terahertz spectroscopic experiments. The proposed dual-heater temperature controller based on a cascade proportional-integral-derivative algorithm provides smooth temperature changes in the polyethylene-based pharmaceutical pellet samples. The device has been integrated with a terahertz time-domain spectrometer. Thermodynamic experiments can now be performed without any probe inserted into the measured sample. Selected results of temperature-induced evolution in terahertz spectra are presented.

  4. Heating system of pellet samples integrated with terahertz spectrometer

    SciTech Connect

    Sterczewski, L. A. Grzelczak, M. P.; Plinski, E. F.

    2016-01-15

    This article describes automation of temperature-dependent terahertz spectroscopic experiments. The proposed dual-heater temperature controller based on a cascade proportional-integral-derivative algorithm provides smooth temperature changes in the polyethylene-based pharmaceutical pellet samples. The device has been integrated with a terahertz time-domain spectrometer. Thermodynamic experiments can now be performed without any probe inserted into the measured sample. Selected results of temperature-induced evolution in terahertz spectra are presented.

  5. Assessment of nitrification potential in ground water using short term, single-well injection experiments

    USGS Publications Warehouse

    Smith, R.L.; Baumgartner, L.K.; Miller, D.N.; Repert, D.A.; Böhlke, J.K.

    2006-01-01

    Nitrification was measured within a sand and gravel aquifer on Cape Cod, MA, using a series of single-well injection tests. The aquifer contained a wastewater-derived contaminant plume, the core of which was anoxic and contained ammonium. The study was conducted near the downgradient end of the ammonium zone, which was characterized by inversely trending vertical gradients of oxygen (270 to 0 ??M) and ammonium (19 to 625 ??M) and appeared to be a potentially active zone for nitrification. The tests were conducted by injecting a tracer solution (ambient ground water + added constituents) into selected locations within the gradients using multilevel samplers. After injection, the tracers moved by natural ground water flow and were sampled with time from the injection port. Rates of nitrification were determined from changes in nitrate and nitrite concentration relative to bromide. Initial tests were conducted with 15N-enriched ammonium; subsequent tests examined the effect of adding ammonium, nitrite, or oxygen above background concentrations and of adding difluoromethane, a nitrification inhibitor. In situ net nitrate production exceeded net nitrite production by 3- to 6- fold and production rates of both decreased in the presence of difluoromethane. Nitrification rates were 0.02-0.28 ??mol (L aquifer)-1 h-1 with in situ oxygen concentrations and up to 0.81 ??mol (L aquifer)-1 h-1 with non-limiting substrate concentrations. Geochemical considerations indicate that the rates derived from single-well injection tests yielded overestimates of in situ rates, possibly because the injections promoted small-scale mixing within a transport-limited reaction zone. Nonetheless, these tests were useful for characterizing ground water nitrification in situ and for comparing potential rates of activity when the tracer cloud included non-limiting ammonium and oxygen concentrations. ?? Springer Science+Business Media, Inc. 2005.

  6. New Experiences With Steam Injection From The MÜhlacker Field Site

    NASA Astrophysics Data System (ADS)

    Theurer, T.; Koschitzky, H.-P.; Färber, A.

    A thermally enhanced remediation scheme employing steam injection has been used at a former hazardous waste disposal site near the City of Mühlacker, Germany, to remove chlorinated solvents. Finding SVE (soil vapour extraction) to be ineffective in the unsaturated soil zone, a pilot-scale project was initiated in 1999 to employ steam injection in the highly contaminated unsaturated low permeable zone 7-15 meters be- low ground surface, limited on top and bottom by very low permeable layers. After completion of the project in September 2001, approximately 2.8 tons of chlorinated hydrocarbons had been removed from the 2500 m3 target area. This project served as a pilot site in the State of Baden-Württemberg EPA (Landesanstalt für Umweltschutz, LfU) site cleanup program, which was funded through the State's "Kommunaler Alt- lastenfonds". Detailed evaluation of SVE technology had indicated that the low permeability in this soil served as a limiting factor for "cold" SVE. As a result, alternative technologies were considered and thermally enhanced SVE by steam injection was selected in 1998 to address the unsaturated zone contaminants. A 20-meter diameter, egg-shaped test- ing area was constructed at the site for pilot-scale demonstration of the steam injection process. The testing area comprised one central injection well surrounded by six ex- traction wells that could be used simultaneously for vapor and liquid extraction. Ten monitoring lances with a total of 100 temperature sensors measured subsurface tem- peratures through the soil horizon. Using a gas-fired 100 kW generator, steam was injected at a rate of up to 100 kg/hour and a pressure of up to 2.5 bars. After ten months of steam injection, nearly complete heating of the target zone had been achieved. of the 2800 kg of TCE removed, approximately 95% was extracted in the gaseous phase and the remaining part as solute in condensed water from the capillary barrier on bottom of the soil horizon. This condensed

  7. Omacetaxine Injection

    MedlinePlus

    ... or cannot take these medications due to side effects. Omacetaxine injection is in a class of medications ... a treatment cycle if you experience serious side effects of the medication or if blood tests show ...

  8. Docetaxel Injection

    MedlinePlus

    ... allergic to docetaxel injection or drugs made with polysorbate 80, an ingredient found in some medications. Ask ... if a medication you are allergic to contains polysorbate 80. If you experience any of the following ...

  9. Oklahoma experiences largest earthquake during ongoing regional wastewater injection hazard mitigation efforts

    NASA Astrophysics Data System (ADS)

    Yeck, W. L.; Hayes, G. P.; McNamara, D. E.; Rubinstein, J. L.; Barnhart, W. D.; Earle, P. S.; Benz, H. M.

    2017-01-01

    The 3 September 2016, Mw 5.8 Pawnee earthquake was the largest recorded earthquake in the state of Oklahoma. Seismic and geodetic observations of the Pawnee sequence, including precise hypocenter locations and moment tensor modeling, shows that the Pawnee earthquake occurred on a previously unknown left-lateral strike-slip basement fault that intersects the mapped right-lateral Labette fault zone. The Pawnee earthquake is part of an unprecedented increase in the earthquake rate in Oklahoma that is largely considered the result of the deep injection of waste fluids from oil and gas production. If this is, indeed, the case for the M5.8 Pawnee earthquake, then this would be the largest event to have been induced by fluid injection. Since 2015, Oklahoma has undergone wide-scale mitigation efforts primarily aimed at reducing injection volumes. Thus far in 2016, the rate of M3 and greater earthquakes has decreased as compared to 2015, while the cumulative moment—or energy released from earthquakes—has increased. This highlights the difficulty in earthquake hazard mitigation efforts given the poorly understood long-term diffusive effects of wastewater injection and their connection to seismicity.

  10. Assessment of electrical conductivity as a surrogate measurement for water samples in a tracer injection experiment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The transport behavior of solutes in streams depends on chemical, physical, biological, and hydrodynamic processes. Although it is a very complex system, it is known that this behavior is greatly influenced by surface and subsurface flows. For this reason, tracer injection in the water flows is one ...

  11. The influence of fish feed pellets on the stability of seabed sediment: A laboratory flume investigation

    NASA Astrophysics Data System (ADS)

    Neumeier, Urs; Friend, Patrick L.; Gangelhof, Uffe; Lunding, Jens; Lundkvist, Morten; Bergamasco, Alessandro; Amos, Carl L.; Flindt, Mogens

    2007-11-01

    Superfluous fish food settling below fish farms can have a negative impact on the seabed. To aid in the assessment of this impact a series of flume experiments, designed to mimic seabed conditions below a fish farm, was conducted with the aim of examining the effects of fish pellets on the stability of fine sediments. Artificial beds, with varying quantities of fish pellets incorporated both within the sediment matrix and lying on the sediment surface, were allowed to consolidate for different periods of time ranging from 1 to 10 days, and then subjected to erosion experiments. In flume experiments containing fish pellets, a bacterial biofilm developed at the sediment-water interface after a few days. In the control experiments (no fish pellets), a diatom biofilm caused extensive stabilisation of the surface sediment. The erosion experiments showed that the addition of fish pellets reduced the surface erosion threshold by more than 50%. The stability decrease was more pronounced in the experiments with greater amounts of pellets. Evidence of drag reduction due to high suspended sediment concentration was also observed. This phenomenon is discussed and a correction formula is proposed for the effective shear stress experienced by the bed.

  12. The design and performance of a twenty barrel hydrogen pellet injector for Alcator C-Mod

    SciTech Connect

    Urbahn, John A.

    1994-05-01

    A twenty barrel hydrogen pellet injector has been designed, built and tested both in the laboratory and on the Alcator C-Mod Tokamak at MIT. The injector functions by firing pellets of frozen hydrogen or deuterium deep into the plasma discharge for the purpose of fueling the plasma, modifying the density profile and increasing the global energy confinement time. The design goals of the injector are: (1) Operational flexibility, (2) High reliability, (3) Remote operation with minimal maintenance. These requirements have lead to a single stage, pipe gun design with twenty barrels. Pellets are formed by in- situ condensation of the fuel gas, thus avoiding moving parts at cryogenic temperatures. The injector is the first to dispense with the need for cryogenic fluids and instead uses a closed cycle refrigerator to cool the thermal system components. The twenty barrels of the injector produce pellets of four different size groups and allow for a high degree of flexibility in fueling experiments. Operation of the injector is under PLC control allowing for remote operation, interlocked safety features and automated pellet manufacturing. The injector has been extrusively tested and shown to produce pellets reliably with velocities up to 1400 m/sec. During the period from September to November of 1993, the injector was successfully used to fire pellets into over fifty plasma discharges. Experimental results include data on the pellet penetration into the plasma using an advanced pellet tracking diagnostic with improved time and spatial response. Data from the tracker indicates pellet penetrations were between 30 and 86 percent of the plasma minor radius.

  13. Ion heating during magnetic relaxation in the helicity injected torus-II experiment

    SciTech Connect

    O'Neill, R.G.; Redd, A.J.; Hamp, W.T.; Smith, R.J.; Jarboe, T.R.

    2005-12-15

    Ion doppler spectroscopy (IDS) is applied to the helicity injected torus (HIT-II) spherical torus to measure impurity ion temperature and flows. [A. J. Redd et al., Phys. Plasmas 9, 2006 (2002)] The IDS instrument employs a 16-channel photomultiplier and can track temperature and velocity continuously through a discharge. Data for the coaxial helicity injection (CHI), transformer, and combined current drive configurations are presented. Ion temperatures for transformer-driven discharges are typically equal to or somewhat lower than electron temperatures measured by Thomson scattering. Internal reconnection events in transformer-driven discharges cause rapid ion heating. The CHI discharges exhibit anomalously high ion temperatures >250 eV, which are an order of magnitude higher than Thomson measurements, indicating ion heating through magnetic relaxation. The CHI discharges that exhibit current and poloidal flux buildup after bubble burst show sustained ion heating during current drive.

  14. Overview of the HL-1M Tokamak Experiments

    SciTech Connect

    Liu Yong; Wang Enyao; Ding Xuantong; Yan Longwen; Qian Shangjie; Yan Jiancheng

    2002-07-15

    Experimental progress with the HL-1M tokamak has been made in many areas including confinement improvement, auxiliary heating, plasma fueling, and wall conditionings. An H-mode induced by a biased electrode was obtained with the formation of an internal transport barrier at the region of r/a {approx} 0.4 to 0.5. Confinement improvement by lower-hybrid current drive (LHCD) was extensively investigated. Confinement improvement seems to be related to the production of the radial electron field during LHCD. In off-axis electron cyclotron resonance heating (ECRH), double sawteeth in soft X-ray radiation were observed, which implies that reversed magnetic shear could be formed during ECRH. At higher ECRH power, when the resonance position is near the q = 1 surface, fishbone instability was observed and investigated. An eight-shot pellet injector was used for the experiments. The pellet ablation process was investigated with a charge-coupled device (CCD) camera and an H{sub {alpha}} emission detector array. Clearly, asymmetry in the pellet cloud was observed in both the toroidal and poloidal directions. It has been found that the pellet velocity slows down clearly after the pellet enters the plasma. The density limit has been investigated on HL-1M at different wall conditionings with three kinds of fueling methods. It was found that a higher density limit could be achieved under the following conditions: (a) a strong reduction of the impurity content after siliconization and (b) a peaked density profile with pellet injection and/or supersonic molecular beam injection. With a neutral beam injection (NBI) system of 1 MW, preliminary results of NBI experiments were obtained with an increase of ion temperature from 450 to 700 eV.

  15. Road Maintenance Experience Using Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization as Ground Rehabilitation

    NASA Astrophysics Data System (ADS)

    Fakhar, A. M. M.; Asmaniza, A.

    2016-07-01

    There are many types of ground rehabilation and improvement that can be consider and implement in engineering construction works for soil improvement in order to prevent road profile deformation in later stage. However, when comes to road maintenance especially on operated expressways, not all method can be apply directly as it must comply to opreation's working window and lane closure basis. Key factors that considering ideal proposal for ground rehabilitation are time, cost, quality and most importantly practicality. It should provide long lifespan structure in order to reduce continuous cycle of maintenance. Thus, this paper will present two approaches for ground rehabilitation, namely Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization. The first approach is an injection system which consists two-parts chemical grout of Isocynate and Polyol when mixed together within soil structure through injection will polymerized with volume expansion. The strong expansion of grouting causes significant compression and compacting of the surrounding soil and subsequently improve ground properties and uplift sunken structure. The later is a cold in-place recyclying whereby mixture process that combines in-situ soil materials, cement, white powder (alkaline) additive and water to produce hard yet flexible and durable ground layer that act as solid foundation with improved bearing capacity. The improvement of the mechanical behaviour of soil through these two systems is investigated by an extensive testing programme which includes in-situ and laboratory test in determining properties such as strength, stiffness, compressibility, bearing capacity, differential settlement and etc.

  16. Electron Temperature Evolution During Local Helicity Injection on the Pegasus Toroidal Experiment

    NASA Astrophysics Data System (ADS)

    Schlossberg, D. J.; Barr, J. L.; Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Perry, J. M.; Reusch, J. A.; Rodriguez Sanchez, C.

    2016-10-01

    Understanding the electron temperature (Te) evolution during local helicity injection (LHI) is critical for scaling up this non-solenoidal startup technique to MA-class devices. The first comprehensive Te measurements during LHI reveal centrally-peaked profiles with Te > 100 eV for plasma current Ip > 120 kA, toroidal field 0.15 T, and electron density ne 1019 m-3. Te rises and is sustained from just after magnetic relaxation through the plasma decoupling from edge-localized injectors. Results are presented for two injector edge locations: outboard midplane and inboard divertor. Outboard midplane injection couples LHI with inductive drive from poloidal field ramps and radial compression during inward plasma growth. Comparisons of Te at different LHI-to-inductive drive ratios show some profile flattening for higher LHI drive fraction. The latter, constant-shape discharges were necessarily lower performance, with Ip 50 kA and reduced Te , max. Inboard divertor injection achieves higher Ip using minimal inductive drive and thus isolates effects of LHI drive on Te. Initial results in this configuration show Te rising rapidly at the injector location as the discharge grows, settling to a roughly flat profile 100 eV. Thus far, both scenarios provide relatively stable discharges with moderate ne and high-Te, suitable for coupling to auxiliary current drive. Detailed studies of confinement dynamics and discharge optimization are planned for the near future. Work supported by US DOE Grant DE-FG02-96ER54375.

  17. Looking West at Line Two Pelletizing Line, Centering Furnaces and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking West at Line Two Pelletizing Line, Centering Furnaces and Dewaxers of First Floor of Pellet Plant - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  18. Estimating shot distance from limited pellets pattern.

    PubMed

    Plebe, Alessio; Compagnini, Domenico

    2012-10-10

    Several methods are available for shooting range estimation based on pellets pattern on the target that have a remarkable degree of accuracy. The task is usually approached working under the assumption that the entire distribution of pellets is available for examination. These methods fail, however, when the victim has been hit by a portion of the pattern only. The problem can be solved with reasonable accuracy when there are areas of void in the victim that are adjacent to the area struck by pellets. This study presents a method that can be used in precisely this type of situation, allowing the estimation of shot distance in cases of partial pellet patterns. It is based on collecting distributions in test shots at several distances, and taking samples in the targets, constrained by the shape of the void and the pellet hit areas. Statistical descriptors of patterns are extracted from such samples, and fed into a neural network classifier, estimating shot ranges of distance.

  19. Radiation analysis of the CIT (Compact Ignition Tokamak) pellet injector system and its impact on personnel access

    SciTech Connect

    Selcow, E.C.; Stevens, P.N.; Gomes, I.C.; Gomes, L.M.

    1988-08-01

    The conceptual design of the Compact Ignition Tokamak (CIT) is nearing completion. The CIT is a short-pulse ignition experiment, which is planned to follow the operations of the Tokamak Fusion Test Reactor (TFTR) at the Princeton Plasma Physics Laboratory (PPPL). The high neutron wall loadings, 4--5 MW/m/sup 2/, associated with the operation of this device require that neutronics-related issues be considered in the overall system design. Radiation shielding is required for the protection of device components as well as personnel. A close-in igloo shield has been designed around the periphery of the tokamak structure, and the entire experiment is housed in a circular test cell facility that has a radius of 12 m. The most critical radiation concerns in the CIT design process relate to the numerous penetrations in the device. This report discusses the impact of a major penetration on the design and operation of the pellet injection system in the CIT. The pellet injector is a major component, and it has a line-of-sight penetration through the igloo and test cell wall. All current options for maintenance of the injector require hands-on-access. A nuclear analysis has been performed to establish the feasibility of hands-on-access. A coupled Monte Carlo/discrete-ordinates methodology was used to perform the analysis. This problem is characterized by deep penetration and streaming with very large length-to-diameter ratios. Results from this study indicate that personnel access to the pellet injector glovebox is possible. 14 refs., 3 figs., 3 tabs.

  20. Bilateral shotgun pellet pulmonary emboli

    PubMed Central

    Huebner, Stephen; Ali, Sayed

    2012-01-01

    Intravascular migration of bullets and other foreign bodies is a rare but known complication of penetrating trauma. Missile embolization can represent a diagnostic challenge because it may present in various and unexpected ways. We present the case of a 54-year-old female who sustained shotgun pellet emboli to the pulmonary arteries following a left upper extremity gunshot wound and related vascular surgery. The case illustrates bilateral embolization, and the embolic events occurred following surgery. Embolization should be considered in evaluating patients with gunshot wounds, particularly if there are anomalous symptoms or the projectile is not found in the original, or expected, location. Close attention to the location of the foreign bodies on serial radiographs may reveal the diagnosis of intravascular embolization. PMID:22690290

  1. Looking Northeast Along Hallway between Pellet Plant and Oxide Building, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Northeast Along Hallway between Pellet Plant and Oxide Building, including Virgin Hopper Bins - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  2. Musculoskeletal Injection

    PubMed Central

    Wittich, Christopher M.; Ficalora, Robert D.; Mason, Thomas G.; Beckman, Thomas J.

    2009-01-01

    Patients commonly present to primary care physicians with musculoskeletal symptoms. Clinicians certified in internal medicine must be knowledgeable about the diagnosis and management of musculoskeletal diseases, yet they often receive inadequate postgraduate training on this topic. The musculoskeletal problems most frequently encountered in our busy injection practice involve, in decreasing order, the knees, trochanteric bursae, and glenohumeral joints. This article reviews the clinical presentations of these problems. It also discusses musculoskeletal injections for these problems in terms of medications, indications, injection technique, and supporting evidence from the literature. Experience with joint injection and the pharmacological principles described in this article should allow primary care physicians to become comfortable and proficient with musculoskeletal injections. PMID:19720781

  3. Transient changes in shallow groundwater chemistry during the MSU ZERT CO2 injection experiment

    USGS Publications Warehouse

    Apps, J.A.; Zheng, Lingyun; Spycher, N.; Birkholzer, J.T.; Kharaka, Y.; Thordsen, J.; Kakouros, E.; Trautz, R.

    2011-01-01

    Food-grade CO2 was injected into a shallow aquifer through a perforated pipe placed horizontally 1-2 m below the water table at the Montana State University Zero Emission Research and Technology (MSU-ZERT) field site at Bozeman, Montana. The possible impact of elevated CO2 levels on groundwater quality was investigated by analyzing 80 water samples taken before, during, and following CO2 injection. Field determinations and laboratory analyses showed rapid and systematic changes in pH, alkalinity, and conductance, as well as increases in the aqueous concentrations of trace element species. The geochemical data were first evaluated using principal component analysis (PCA) in order to identify correlations between aqueous species. The PCA findings were then used in formulating a geochemical model to simulate the processes likely to be responsible for the observed increases in the concentrations of dissolved constituents. Modeling was conducted taking into account aqueous and surface complexation, cation exchange, and mineral precipitation and dissolution. Reasonable matches between measured data and model results suggest that: (1) CO2 dissolution in the groundwater causes calcite to dissolve. (2) Observed increases in the concentration of dissolved trace metals result likely from Ca+2-driven ion exchange with clays (smectites) and sorption/desorption reactions likely involving Fe (hydr)oxides. (3) Bicarbonate from CO2 dissolution appears to compete for sorption with anionic species such as HAsO4-2, potentially increasing dissolved As levels in groundwater. ?? 2011 Published by Elsevier Ltd.

  4. Preferential heating of light ions during an ionospheric AR(+) injection experiment

    NASA Technical Reports Server (NTRS)

    Pollock, C. J.; Moore, T. E.; Arnoldy, R. L.; Kintner, P. M.; Cahill, L. J., Jr.

    1994-01-01

    The ARCS 4 sounding rocket was launched northward into high altitude from Poker Flat Research Range on February 23, 1990. The vehicle crossed geomagnetic field lines containing discrete auroral activity. An instrumented subpayload released 100 ev and 200 ev Ar(+) ion beams sequentially, in a direction largely perpendicular to both the local geomagnetic field and the subpayload spin axis. The instrumented main payload was separated along field lines from the beam emitting subpayload by a distance which increased at a steady rate of approx. 2.4 m/s. Three-dimensional mass spectrometric ion observations of ambient H(+) and O(+) ions, obtained onboard the main payload, are presented. Main payload electric field observations in the frequency range 0-16 kHz, are also presented. These observations are presented to demonstrate the operation of transverse ion acceleration, that was differential with respect to ion mass, primarily during 100-ev beam operations. The preferential transverse acceleration of ambient H(+) ions, as compared with ambient O(+) ions during the second, third, fourth, and fifth 100-ev beam operations, is attributed to a resonance at the injected the beam drift velocity among the thermal H(+) ions and plasma waves generated by the injected beam and propagating at the beam drift speed. This work provides experimental support of processes predicted by previously published theory and simulations.

  5. [Experiences with pain control during piglet castration in Switzerland Part 2: Injection anesthesia].

    PubMed

    Enz, A; Schüpbach-Regula, G; Bettschart, R; Fuschini, E; Bürgi, E; Sidler, X

    2013-12-01

    The aim of this study was to describe the practical implementation of the painless castration under injection anaesthesia in Switzerland. 30 swine farms were visited and 60 farmers answered a questionnaire. 34 % of the piglets showed movements during castration under injection anaesthesia and 17 % had excitations during recovery from anaesthesia. After 48 minutes half of the piglets were in sternal position and after 112 minutes half of them showed coordinated movements. The body temperature decreased by 3.1 °C until 60 minutes after castration, especially small piglets reached critical temperature levels. 38 % of the piglets showed strong bleeding after castration. The healing of the wound was good according to 82 % of the farmers. 83 % of the farmers reported piglet losses, especially at the beginning of the anaesthesia period. The anaesthesia may be improved by using butorphanol in addition to the combination of ketamine and azaperone. The recovery of the piglets should be in a warm place without any risk of injury by obstacles or the sow. Increased bleeding can be controlled by using an emasculator.

  6. Bulk and Surface Molecular Orientation Distribution in Injection-molded Liquid Crystalline Polymers: Experiment and Simulation

    SciTech Connect

    Fang, J.; Burghardt, W; Bubeck, R; Burgard, S; Fischer, D

    2010-01-01

    Bulk and surface distributions of molecular orientation in injection-molded plaques of thermotropic liquid crystalline polymers (TLCPs) have been studied using a combination of techniques, coordinated with process simulations using the Larson-Doi 'polydomain' model. Wide-angle X-ray scattering was used to map out the bulk orientation distribution. Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR) and Near-Edge X-ray Absorption Fine Structure (NEXAFS) were utilized to probe the molecular orientation states to within about {approx}5 {micro}m and {approx}2 nm, respectively, of the sample surface. These noninvasive, surface-sensitive techniques yield reasonable self-consistency, providing complementary validation of the robustness of these methods. An analogy between Larson-Doi and fiber orientation models has allowed the first simulations of TLCP injection molding. The simulations capture many fine details in the bulk orientation distribution across the sample plaque. Direct simulation of surface orientation at the level probed by FTIR-ATR and NEXAFS was not possible due to the limited spatial resolution of the simulations. However, simulation results extracted from the shear-dominant skin region are found to provide a qualitatively accurate indicator of surface orientation. Finally, simulations capture the relation between bulk and surface orientation states across the different regions of the sample plaque.

  7. Automated fabrication, characterization and transport of ICF pellets. Final report, March 1, 1979-October 31, 1980

    SciTech Connect

    Clifford, D W; Boyd, B A; Lilienkamp, R H

    1980-12-01

    The near-term objectives of the contract were threefold: (1) evaluate techniques for the production of frozen hydrogen microspheres and demonstrate concepts for coating them; (2) develop and demonstrate an optical characterization system which could lead to automated pellet inspection; and (3) develop and demonstrate a preliminary electrostatic pellet transport control system. This report describes the equipment assembled for these experiments and the results obtained.

  8. New Electron Temperature Measurements During Local Helicity Injection and H-mode Plasmas at the Pegasus Toroidal Experiment

    NASA Astrophysics Data System (ADS)

    Schlossberg, D. J.; Bodner, G. M.; Fonck, R. J.; Reusch, J. A.; Winz, G. R.

    2015-11-01

    Extrapolation of non-solenoidal startup via local helicity injection (LHI) to larger devices depends critically on confinement during the injection process. To begin quantifying confinement regimes, the Thomson scattering diagnostic on the Pegasus ST was upgraded to include 12 radial positions and high temperature (0.1 Experiments are underway to verify these unexpectedly high electron temperatures. If verified, these temperatures may reflect the dominance of high-energy electrons via fueling with LHI current streams with average energy ~1 keV. Further investigations will explore the dependence of the inferred electron distribution on fueling source, density, and electron injection potential. The upgraded Thomson scattering diagnostic will also be applied to Ohmic H-mode plasmas in Pegasus. Work supported by US DOE grant DE-FG02-96ER54375.

  9. Pelletization of fine coals. Final report

    SciTech Connect

    Sastry, K.V.S.

    1995-12-31

    Coal is one of the most abundant energy resources in the US with nearly 800 million tons of it being mined annually. Process and environmental demands for low-ash, low-sulfur coals and economic constraints for high productivity are leading the coal industry to use such modern mining methods as longwall mining and such newer coal processing techniques as froth flotation, oil agglomeration, chemical cleaning and synthetic fuel production. All these processes are faced with one common problem area--fine coals. Dealing effectively with these fine coals during handling, storage, transportation, and/or processing continues to be a challenge facing the industry. Agglomeration by the unit operation of pelletization consists of tumbling moist fines in drums or discs. Past experimental work and limited commercial practice have shown that pelletization can alleviate the problems associated with fine coals. However, it was recognized that there exists a serious need for delineating the fundamental principles of fine coal pelletization. Accordingly, a research program has been carried involving four specific topics: (i) experimental investigation of coal pelletization kinetics, (ii) understanding the surface principles of coal pelletization, (iii) modeling of coal pelletization processes, and (iv) simulation of fine coal pelletization circuits. This report summarizes the major findings and provides relevant details of the research effort.

  10. A centrifuge CO2 pellet cleaning system

    NASA Technical Reports Server (NTRS)

    Foster, C. A.; Fisher, P. W.; Nelson, W. D.; Schechter, D. E.

    1995-01-01

    An advanced turbine/CO2 pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory (ORNL). The program, sponsored by Warner Robins Air Logistics Center (ALC), Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air 'sandblast' pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting and by combining the use of environmentally benign solvents with the pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies.

  11. Experience of direct percutaneous sac injection in type II endoleak using cone beam computed tomography.

    PubMed

    Park, Yoong-Seok; Do, Young Soo; Park, Hong Suk; Park, Kwang Bo; Kim, Dong-Ik

    2015-04-01

    Cone beam CT, usually used in dental area, could easily obtain 3-dimensional images using cone beam shaped ionized radiation. Cone beam CT is very useful for direct percutaneous sac injection (DPSI) which needs very precise measurement to avoid puncture of inferior vena cava or vessel around sac or stent graft. Here we describe two cases of DPSI using cone beam CT. In case 1, a 79-year-old male had widening of preexisted type II endoleak after endovascular aneurysm repair (EVAR). However, transarterial embolization failed due to tortuous collateral branches of lumbar arteries. In case 2, a 72-year-old female had symptomatic sac enlargement by type II endoleak after EVAR. However, there was no route to approach the lumbar arteries. Therefore, we performed DPSI assisted by cone beam CT in cases 1, 2. Six-month CT follow-up revealed no sign of sac enlargement by type II endoleak.

  12. Estimation of Sintering Kinetics of Oxidized Magnetite Pellet Using Optical Dilatometer

    NASA Astrophysics Data System (ADS)

    Sandeep Kumar, T. K.; Viswanathan, Neelakantan Nurni; Ahmed, Hesham M.; Andersson, Charlotte; Björkman, Bo

    2015-04-01

    The quality of magnetite pellet is primarily determined by the physico-chemical changes the pellet undergoes as it makes excursion through the gaseous and thermal environment in the induration furnace. Among these physico-chemical processes, the oxidation of magnetite phase and the sintering of oxidized magnetite (hematite) and magnetite (non-oxidized) phases are vital. Rates of these processes not only depend on the thermal and gaseous environment the pellet gets exposed in the induration reactor but also interdependent on each other. Therefore, a systematic study should involve understanding these processes in isolation to the extent possible and quantify them seeking the physics. With this motivation, the present paper focusses on investigating the sintering kinetics of oxidized magnetite pellet. For the current investigation, sintering experiments were carried out on pellets containing more than 95 pct magnetite concentrate from LKAB's mine, dried and oxidized to completion at sufficiently low temperature to avoid sintering. The sintering behavior of this oxidized pellet is quantified through shrinkage captured by Optical Dilatometer. The extent of sintering characterized by sintering ratio found to follow a power law with time i.e., Kt n . The rate constant K for sintering was determined for different temperatures from isothermal experiments. The rate constant, K, varies with temperature as and the activation energy ( Q) and reaction rate constant ( K') are estimated. Further, the sintering kinetic equation was also extended to a non-isothermal environment and validated using laboratory experiments.

  13. Initial Thomson Scattering Survey of Local Helicity Injection and Ohmic Plasmas at the Pegasus Toroidal Experiment

    NASA Astrophysics Data System (ADS)

    Schlossberg, D. J.; Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Winz, G. R.

    2014-10-01

    A multipoint Thomson scattering diagnostic has recently been installed on the Pegasus ST. The system utilizes a frequency-doubled Nd:YAG laser (λ0 ~ 532 nm), spectrometers with volume phase holographic gratings, and a gated, intensified CCD camera. It provides measurements of Te and ne at 8 spatial locations for each spectrometer once per discharge. A new multiple aperture and beam dump system has been implemented to mitigate interference from stray light. This system has provided initial measurements in the core region of plasmas initiated by local helicity injection (LHI), as well as conventional Ohmic L- and H-mode discharges. Multi-shot averages of low-density (ne ~ 3 ×1018 m-3) , Ip ~ 0 . 1 MA LHI discharges show central Te ~ 75 eV at the end of the helicity injection phase. Ip ~ 0 . 13 MA Ohmic plasmas at moderate densities (ne ~ 2 ×1019 m-3) have core Te ~ 150 eV in L-mode. Generally, these plasmas do not reach transport equilibrium in the short 25 ms pulse length available. After an L-H transition, strong spectral broadening indicates increasing Te, to values above the range of the present spectrometer system with a high-dispersion VPH grating. Near-term system upgrades will focus on deploying a second spectrometer, with a lower-dispersion grating capable of measuring the 0.1-1.0 keV range. The second spectrometer system will also increase the available number of spatial channels, enabling study of H-mode pedestal structure. Work supported by US DOE Grant DE-FG02-96ER54375.

  14. Asymptotic analysis soot model and experiment for a directed injection engine

    NASA Astrophysics Data System (ADS)

    Liu, Yongfeng; Pei, Pucheng; Xiong, Qinghui; Lu, Yong

    2012-09-01

    The existing soot models are either too complex and can not be applied to the internal combustion engine, or too simple to make calculation errors. Exploring the soot model becomes the pursuit of the goal of many researchers within the error range in the current computer speed. On the basis of the latest experimental results, TP (temperature phases) model is presented as a new soot model to carry out optimization calculation for a high-pressure common rail diesel engine. Temperature and excess air factor are the most important two parameters in this model. When zone temperature T<1 500 K and excess air factor Φ>0.6, only the soot precursors—polycyclic aromatic hydrocarbons(PAH) is created and there is no soot emission. When zone temperature T ⩾ 1 500 K and excess air factor Φ<0.6, PAHs and soot source terms (particle inception, surface growth, oxidation, coagulation) are calculated. The TP model is then implemented in KIVA code instead of original model to carry out optimizing. KIVA standard model and experimental data are analyzed for the results of cylinder pressures, the corresponding heat release rates, and soot with variation of injection time, variation of rail pressure and variation of speed among TP models. The experimental results indicate that the TP model can carry out optimization and computational fluid dynamics can be a tool to calculate for a high-pressure common rail directed injection diesel engine. The TP model result is closer than the use of the original KIVA-3V results of soot model accuracy by about 50% and TP model gives a new method for engine researchers.

  15. [Experience of using injectable formulation of buprenorphine for the detoxification treatment of heroin dependence patients].

    PubMed

    Aso, Katsuro

    2009-06-01

    Forty-four heroin dependence patients took detoxification treatment in Fukko-kai Tarumi Hospital from October 1998 to April 2008 (total of 80 admissions). Injectable formulation of buprenorphine (0.2 mg) was used intramuscularly to relieve withdrawal symptoms from October 2002. In the initial phase, small dosage of buprenorphine (0.4 mg per day) was dispensed but obvious effects were not confirmed. Therefore, the dosage was increased to 0.6 mg (3 ampoules), possibly more for 27 patients (total of 53 admissions) from October 2005. While treatment was interrupted by various reasons in 6 patients (total of 10 admissions), the rest completed detoxification. Dosage of buprenorphine given to the patients varied from 0.6 mg (3 ampoules) to 1.6 mg (8 ampoules) per day, and only 4 patients required over 1.0 mg. While duration of administration ranged from 5 days to 15 days, it was between 7 days and 10 days in over the half cases. When sufficient amount of buprenorphine was administered, severity and duration of heroin withdrawal symptoms was distinctly reduced. Since the introduction of heroin detoxification with buprenorphine, number of patients who request the treatment voluntarily increased including those who relapsed, but the length of hospital stay was shortened. One patient rejected buprenorphine injection for unknown reason and one patient left the hospital because of insufficient effect due to insufficient amount of buprenorphine dose, serious adverse effect was not observed. Detoxification treatment with buprenorphine cannot ensure sustained abstinence but can motivate heroin-using patients to receive treatment and strive for abstinence.

  16. Decomposition of oak leaf litter and millipede faecal pellets in soil under temperate mixed oak forest

    NASA Astrophysics Data System (ADS)

    Tajovský, Karel; Šimek, Miloslav; Háněl, Ladislav; Šantrůčková, Hana; Frouz, Jan

    2015-04-01

    The millipedes Glomeris hexasticha (Diplopoda, Glomerida) were maintained under laboratory conditions and fed on oak leaf litter collected from a mixed oak forest (Abieto-Quercetum) in South Bohemia, Czech Republic. Every fourth day litter was changed and produced faecal pellets were separated and afterwards analysed. Content of organic carbon and C:N ratio lowered in faecal pellets as compared with consumed litter. Changes in content of chemical elements (P, K, Ca, Mg, Na) were recognised as those characteristic for the first stage of degradation of plant material. Samples of faecal pellets and oak leaf litter were then exposed in mesh bags between the F and H layers of forest soil for up to one year, subsequently harvested and analysed. A higher rate of decomposition of exposed litter than that of faecal pellets was found during the first two weeks. After 1-year exposure, the weight of litter was reduced to 51%, while that of pellets to 58% only, although the observed activity of present biotic components (algae, protozoans, nematodes; CO2 production, nitrogenase activity) in faecal pellets was higher as compared with litter. Different micro-morphological changes were observed in exposed litter and in pellets although these materials originated from the same initial sources. Comparing to intact leaf litter, another structural and functional processes occurred in pellets due to the fragmentation of plant material by millipedes. Both laboratory and field experiments showed that the millipede faecal pellets are not only a focal point of biodegradation activity in upper soil layers, but also confirmed that millipede feces undergo a slower decomposition than original leaf litter.

  17. Parameters of the luminous region surrounding deuterium pellets in the PLT tokamak

    SciTech Connect

    McNeill, D.H.; Greene, G.J.; Schuresko, D.D.

    1985-08-01

    The luminous region of the plasma cloud surrounding deuterium pellets injected into a tokamak is studied spectroscopically. At the time of peak luminosity the average electron density is 2.4 x 10/sup 17/ cm/sup -3/ to within 30% and the temperature is at most 2.0 eV. The intensity ratio of the Balmer alpha and beta light from the pellets, the total number of emitted photons, and the apparent size of the radiating region are consistent with local thermodynamic equilibrium at this temperature and density.

  18. Microbiological survey of birds of prey pellets.

    PubMed

    Dipineto, Ludovico; Bossa, Luigi Maria De Luca; Pace, Antonino; Russo, Tamara Pasqualina; Gargiulo, Antonio; Ciccarelli, Francesca; Raia, Pasquale; Caputo, Vincenzo; Fioretti, Alessandro

    2015-08-01

    A microbiological survey of 73 pellets collected from different birds of prey species housed at the Wildlife Rescue and Rehabilitation Center of Napoli (southern Italy) was performed. Pellets were analyzed by culture and biochemical methods as well as by serotyping and polymerase chain reaction. We isolated a wide range of bacteria some of them also pathogens for humans (i.e. Salmonella enterica serotype Typhimurium, Campylobacter coli, Escherichia coli O serogroups). This study highlights the potential role of birds of prey as asymptomatic carriers of pathogenic bacteria which could be disseminated in the environment not only through the birds of prey feces but also through their pellets.

  19. Laboratory simulations of the Viking Labeled Release experiment - Kinetics following second nutrient injection and the nature of the gaseous end product

    NASA Technical Reports Server (NTRS)

    Levin, G. V.; Straat, P. A.

    1979-01-01

    Injection of (C-14)-labeled nutrient onto Mars soil produced an evolution of C-14 gas in the Viking Labeled Release (LR) experiment. However, a second injection of nutrient seven days later was followed by an abrupt diminution of the amount of radioactive gas in the test cell. Simulation experiments performed in the LR Test Standards Module (TSM) have yielded a plausible explanation for this diminution. Radioactive carbon gases were injected into the TSM test cell in the presence and absence of two Mars analog soils. After equilibration, water was injected and its effect observed. The results indicate that the flight data following second nutrient injection can be explained on a physico-chemical basis involving a carbon dioxide/water/soil equilibrium in the test cell. The results also suggest that the gaseous end product of the Labeled Release reaction on Mars is more likely carbon dioxide than carbon monoxide.

  20. EMC3-EIRENE modelling of toroidally-localized divertor gas injection experiments on Alcator C-Mod

    SciTech Connect

    Lore, Jeremy D.; Reinke, M. L.; LaBombard, Brian; Lipschultz, B.; Churchill, R. M.; Pitts, R. A.; Feng, Y.

    2014-09-30

    Experiments on Alcator C-Mod with toroidally and poloidally localized divertor nitrogen injection have been modeled using the three-dimensional edge transport code EMC3-EIRENE to elucidate the mechanisms driving measured toroidal asymmetries. In these experiments five toroidally distributed gas injectors in the private flux region were sequentially activated in separate discharges resulting in clear evidence of toroidal asymmetries in radiated power and nitrogen line emission as well as a ~50% toroidal modulation in electron pressure at the divertor target. The pressure modulation is qualitatively reproduced by the modelling, with the simulation yielding a toroidal asymmetry in the heat flow to the outer strike point. Finally, toroidal variation in impurity line emission is qualitatively matched in the scrape-off layer above the strike point, however kinetic corrections and cross-field drifts are likely required to quantitatively reproduce impurity behavior in the private flux region and electron temperatures and densities directly in front of the target.

  1. Geophysical monitoring of near surface CO2 injection at Svelvik - Learnings from the CO2FieldLab experiments.

    NASA Astrophysics Data System (ADS)

    Querendez, Etor; Romdhane, Anouar; Jordan, Michael; Eliasson, Peder; Grimstad, Alv-Arne

    2014-05-01

    A CO2 migration field laboratory for testing monitoring methods and tools has been established in the glaciofluvial-glaciomarine Holocene deposits of the Svelvik ridge, near Oslo (Norway). At the site, feasibility, sensitivity, acquisition geometry and usefulness of various surface and subsurface monitoring tools are investigated during controlled CO2 injection experiments. In a first stage, a shallow CO2 injection experiment was conducted in September 2011. Approximately 1700 kg of CO2 was injected at 18 m depth below surface in an unconsolidated sand formation. The objectives of this experiment were to (i) detect and, where possible, quantify migrated CO2 concentrations at the surface and very shallow subsurface, (ii) evaluate the sensitivity of the monitoring tools and (iii) study the impact of the vadose zone on observed measurements. Results showed that all deployed monitoring tools (for surface and near-surface gas monitoring, subsurface water monitoring and subsurface geophysical monitoring) where able to detect the presence of CO2 even though the CO2 plume did not migrate vertically as expected in what was thought to be an homogeneous unconsolidated sand structure. The upper part of the site revealed to be more heterogeneous than expected, mainly due to the highly variable lamination and channelling of the morainic sediments and to the presence of pebble and cobble beds sporadically showing throughout the deposits. Building on the learnings from the 18m depth injection experiment, a second experiment is being planned for a deeper injection, at a depth of 65m. Re-processing of the appraisal 2D multi-channel seismic with state-of-the-art processing techniques, like Linear Radon coherent and random noise attenuation and Full Waveform Inversion followed by pre-stack depth migration, corroborate the presence of heterogeneities at the near surface. Based on the re-interpreted seismic sections, a more realistic 3D geomodel, where the complex topography of the site

  2. Study on the Structures of Two Booster Pellets Having High Initiation Capacity

    NASA Astrophysics Data System (ADS)

    Shuang-Qi, Hu; Hong-Rong, Liu; Li-shuang, Hu; Xiong, Cao; Xiang-Chao, Mi; Hai-Xia, Zhao

    2014-05-01

    Insensitive munitions (IM) improve the survivability of both weapons and their associated platforms, which can lead to a reduction in casualties, mission losses, and whole life costs. All weapon systems contain an explosive train that needs to meet IM criteria but reliably initiate a main charge explosive. To ensure that these diametrically opposed requirements can be achieved, new highly effective booster charge structures were designed. The initiation capacity of the two booster pellets was studied using varied composition and axial-steel-dent methods. The results showed that the two new booster pellets can initiate standard main charge pellets with less explosive mass than the ordinary cylindrical booster pellet. The numerical simulation results were in good agreement with the experiment results.

  3. Biological improvement on combined mycelial pellet for aniline treatment by tourmaline in SBR process.

    PubMed

    Zhang, Si; Li, Ang; Cui, Di; Duan, Shuyue; Yang, Jixian; Ma, Fang; Shi, Shengnan; Ren, Nanqi

    2011-10-01

    As a biomass carrier, mycelial pellet of Aspergillus niger Y3 was used to immobilize the aniline-degrading bacterium Acinetobacter calcoaceticus JH-9 and the mix culture of the COD rapid degrading bacteria in this study. Tourmaline was added to this system in order to improve the aniline removal performance using combined mycelial pellet. Flask experiments were performed to investigate the promotion mechanism. The results showed that the start-up time was shorted from 7 cycles to only 1 cycle. The aniline and COD concentration in effluent were much lower in the tourmaline-adding system. It was suggested that tourmaline could enhance the number and activity of the aniline-degrading bacteria immobilized on the mycelial pellet. Therefore, the performance of mycelial pellet as a biomass carrier could be improved by tourmaline.

  4. Preferential heating of light ions during an ionospheric Ar(+) injection experiment

    SciTech Connect

    Pollock, C.J.; Chandler, M.O.; Moore, T.E.; Arnoldy, R.L.; Kintner, P.M.; Chesney, S.; Cahill, L.J. Jr.

    1995-08-01

    The Argon Release for Controlled Studies (ARCS) 4 sounding rocket was launched northward into high altitude from Poker Flat Research Range on February 23, 1990. The vehicle crossed geomagnetic field lines containing discrete auroral activity. An instrumented subpayload released 100-eV and 200-eV Ar(+) ion beams sequentially, in a direction largely perpendicular to both the local geomagnetic field and the subpayload spin axis. The instrumented main payload was separated along field lines from the beam emitting subpayload by a distance which increased at a steady rate of approximately 2.4 m/s. Three dimensional mass spectrometric ion observations of ambient H(+) and O(+) ions, obtained on board the main payload, are presented. Main payload electric field observations in the frequency range 0-16 kHz, are also presented. These observations are presented to demonstrate the operation of transverse ion acceleration, which was differential with respect to ion mass, primarily during 100-eV beam operations. The preferential transverse acceleration of ambient H(+) ions, as compared with ambient O(+) ions, during the second, third, fourth, and fifth 100-eV beam operations, is attributed to a resonance among the injected Ar(+) ions, beam-generated lower hybrid waves, and H(+) ions in the tail of the ambient thermal distribution. This work provides experimental support of processes predicted by previously published theory and simulations.

  5. Preferential heating of light ions during an ionospheric Ar(+) injection experiment

    NASA Technical Reports Server (NTRS)

    Pollock, C. J.; Chandler, M. O.; Moore, T. E.; Arnoldy, R. L.; Kintner, P. M.; Chesney, S.; Cahill, L. J., Jr.

    1995-01-01

    The Argon Release for Controlled Studies (ARCS) 4 sounding rocket was launched northward into high altitude from Poker Flat Research Range on February 23, 1990. The vehicle crossed geomagnetic field lines containing discrete auroral activity. An instrumented subpayload released 100-eV and 200-eV Ar(+) ion beams sequentially, in a direction largely perpendicular to both the local geomagnetic field and the subpayload spin axis. The instrumented main payload was separated along field lines from the beam emitting subpayload by a distance which increased at a steady rate of approximately 2.4 m/s. Three dimensional mass spectrometric ion observations of ambient H(+) and O(+) ions, obtained on board the main payload, are presented. Main payload electric field observations in the frequency range 0-16 kHz, are also presented. These observations are presented to demonstrate the operation of transverse ion acceleration, which was differential with respect to ion mass, primarily during 100-eV beam operations. The preferential transverse acceleration of ambient H(+) ions, as compared with ambient O(+) ions, during the second, third, fourth, and fifth 100-eV beam operations, is attributed to a resonance among the injected Ar(+) ions, beam-generated lower hybrid waves, and H(+) ions in the tail of the ambient thermal distribution. This work provides experimental support of processes predicted by previously published theory and simulations.

  6. Semi-continuous treatment of recalcitrant anaerobic effluent from pulp and paper industry using hybrid pellets of Trametes versicolor.

    PubMed

    Ortega-Clemente, A; Ponce-Noyola, M T; Montes-Horcasitas, M C; Vicent, M T; Barrera-Cortés, J; Poggi-Varaldo, H M

    2007-01-01

    The objective of this work was to evaluate the semi-continuous post-treatment of anaerobically-pre-treated weak black liquor (anaerobic effluent, AnE) by aerobic post-treatment using hybrid pellets of Trametes versicolor. The latter consisted of fungus immobilized onto holm oak sawdust (mixed or double pellets) or a mixture of holm oak sawdust and powdered activated carbon (triple pellets). First, a semicontinuous experiment was run to compare the effectiveness of triple and mixed pellets in agitated flasks for 15 cycles of 7 days each. A second extended batch test was implemented with 500 mL AnE and triple pellets to give 400 mg fungal biomass; some units were spiked with protease inhibitor. In the first experiment, triple pellets displayed consistently higher removal efficiencies of pollutant parameters than double pellets (10 to 15% higher), although overall averages were moderate and no statistical significance to the difference could be set because of the noise of fluctuations. Periodic fluctuations of removal were characterized by three periods of approximately six cycles each with maximum removals occurring at cycles 3-4, 7-9, 13, and 14. Evaluating pooled removals of the latter cycles showed that triple pellets were significantly more effective than double pellets, with removal efficiencies as high as 47% of COD, colour, and absorbance at 254 nm (A254). In general, protease activity seemed to increase in the third period (last six cycles), whereas activities of MnP, LiP and Lac significantly decreased. In the second experiment, pollutant removals and enzymatic activities of triple pellets with protease inhibitor were significantly higher than those of units without added protease inhibitor. These results indicate that protease could be the main cause of periodic falls of pollutant removal efficiencies found in the first experiment.

  7. Effect of calcium sulfate-chitosan composite: pellet on bone formation in bone defect.

    PubMed

    Cho, Byung Chae; Kim, Tae Gyu; Yang, Jung Duk; Chung, Ho Yun; Park, Jae Woo; Kwon, Ick Chan; Roh, Kyung Ho; Chung, Hye Sun; Lee, Dong Sin; Park, Nang Un; Kim, In San

    2005-03-01

    The purpose of this experiment was to study the effects of chitosan, calcium sulfate, and calcium sulfate-chitosan composite pellet on the osteogenesis of defective tibia in rabbits. Eighty New Zealand white rabbits, each weighing approximately 3 to 3.5 kg, were used for this study. A 1-cm ostectomy was made on the middle of the tibia of each rabbit with the periosteum preserved. Nothing was implanted in the control group (group 1), and five chitosan pellets (60 mg/pellet) were implanted in group 1, three OsteoSet pellets (100 mg/pellet) in group 3, and four calcium sulfate-chitosan composite pellets (1 pellet, 80 mg; calcium sulfate 40 mg/pellet, chitosan 40 mg/pellet) in group 4. For each group, a radiographic study, bone mineral density test, three-point bending test, and histologic examination were performed in the second, fourth, and sixth weeks. In the radiologic study, in group 1, cortical bone was not formed even at 6 weeks. In group 2, it was observed at 6 weeks. In groups 3 and 4, cortical bone was partially seen around the fourth week. At 6 weeks, it was clearly observed on both sides, and the projection of the marrow cavity became distinctive, so bone consolidation was considered to be much progressed. The bone mineral density test and three-point bending test results appeared to be highly similar in groups 3 and 4 and in groups 2 and 1. Particularly at 6 weeks, the measures for groups 3 and 4 were statistically significant compared with those for groups 1 and 2 (P < 0.05). In histologic examination, new bone formation began to be seen at 2 weeks in all groups, but it was more active and faster in groups 3 and 4. At 6 weeks, fibrous connective tissue still remained at the center in groups 1 and 2; however, the fibrous connective tissue at the center was replaced with callus, the bony bridge was obvious, and lamellation of callus was observed more in groups 3 and 4. The results indicate that chitosan pellets, OsteoSet, and chitosan-calcium sulfate

  8. Modeling of a Hydrogenic Pellet Production System

    NASA Astrophysics Data System (ADS)

    Leachman, J. W.; Pfotenhauer, J. M.; Nellis, G. F.

    2010-04-01

    Solid hydrogenic pellets are used as fuel for fusion energy machines like the ITER device. This paper discusses the numerical modeling of a Pellet Production System (PPS) that is used to generate these pellets. The PPS utilizes a source of supercritical helium to provide the cooling that is necessary to precool, liquefy, and solidify hydrogenic material that is ultimately extruded and cut into fuel pellets. The specific components within the PPS include a pre-cooling heat exchanger, a liquefier, and a twin-screw solidifying extruder. This paper presents numerical models of each component. These numerical models are used as design tools to predict the performance of the respective devices. The performance of the PPS is dominated by the heat transfer coefficient and viscous dissipation associated with the solidifying hydrogenic fluid in the twin-screw extruder. This observation motivates experimental efforts aimed at precise measurement of these quantities.

  9. Hydrogen Uptake of DPB Getter Pellets

    SciTech Connect

    Dinh, L N; Schildbach, M A; Herberg, J L; Saab, A P; Weigle, J; Chinn, S C; Maxwell, R S; McLean II, W

    2008-05-30

    The physical and chemical properties of 1,4-diphenylbutadiyne (DPB) blended with carbon-supported Pd (DPB-Pd/C) in the form of pellets during hydrogenation were investigated. A thermogravimetric analyzer (TGA) was employed to measure the kinetics of the hydrogen uptake by the DPB getter pellets. The kinetics obtained were then used to develop a semi-empirical model, based on gas diffusion into solids, to predict the performance of the getter pellets under various conditions. The accuracy of the prediction model was established by comparing the prediction models with independent experimental data on hydrogen pressure buildup in sealed systems containing DPB getter pellets and subjected to known rates of hydrogen input. The volatility of the hydrogenated DPB products and its effects on the hydrogen uptake kinetics were also analyzed.

  10. Apparatus for feeding nuclear fuel pellets to a loading tray

    SciTech Connect

    Huggins, T.B.

    1981-12-08

    Apparatus for feeding nuclear fuel pellets at a uniform, predetermined rate between pellet centering and grinding apparatus and a tray used for loading pellets into a nuclear fuel rod are described. Pellets discharged from the grinder are conveyed by a woven wire belt to a drive wheel which develops a force available to be applied to pellets preceding it on the belt. The pellets pass under the drive wheel which adds additional weight acting vertically on each pellet. This total weight of pellet and drive wheel coupled with wire belt linear movement acts to push a line of about 36 pellets onto a pellet dumping mechanism. As the dumping mechanism is actuated to dump the pellets on to a loading tray, the pellets moving toward the mechanism are clamped in a stationary position and the drive wheel simultaneously is lifted from its pellet contacting position until the pellet dumping process is completed. The clamping device is then lifted from its pellet and the drive wheel simultaneously is lowered into a pellet contacting position.

  11. The effect of polycarbophil on the gastric emptying of pellets.

    PubMed

    Khosla, R; Davis, S S

    1987-01-01

    The influence of the putative bioadhesive, polycarbophil, on the gastric emptying of a pellet formulation, has been investigated in three fasted subjects. The pellets were radiolabelled with technetium-99m. Gastric emptying was measured using the technique of gamma scintigraphy. The pellets emptied from the stomach rapidly and in an exponential manner. Polycarbophil did not retard the gastric emptying of the pellets.

  12. Effect of pellet coatings on PETN porosity and slapper detonator efficacy

    NASA Astrophysics Data System (ADS)

    Brown, Kathryn E.; Monroe, Deirdre C.; Brown, Geoffrey W.

    2017-01-01

    Pentaerythritol tetranitrate (PETN) is well known to have a high vapor pressure and to sublime and decompose when heated. Preliminary experiments conducted in 2014 suggest that at 80°C for 6 days, a 1.65 g/cm3 PETN pellet will develop crystals and a layer of increased porosity on the pellet surface, due to sublimation and re-deposition of PETN crystals in an equilibrium environment. This phenomenon may decrease the pressed PETN pellet's sensitivity to shock initiation in a slapper detonator. In this report, we detail preliminary attempts to mitigate sublimation and recrystallization by coating the flyer impact surface of pressed PETN pellets with 200 nm of gold. No crystallization occurred on the surface of the coated, heated surface, and firing thresholds for the coated pellets did not appreciably change with heating. Recent attempts to replicate the effects of heating bare PETN pellets contradict the 2014 experiments, and potential explanations include different PETN batches and different heating schemes. Current and future research directions, including coating with Parylene C, are also presented.

  13. Study of the influence of alkalizing components on matrix pellets prepared by extrusion/spheronization.

    PubMed

    Hamedelniel, Elnazeer I; Bajdik, János; Kása, Péter; Pintye-Hódi, Klára

    2012-01-01

    The aim of this study was to investigate the effects of alkalizing components and the nature of the wetting liquid on the properties of matrix pellets prepared by extrusion and spheronization. Atenolol was used as an active pharmaceutical ingredient, ethylcellulose as a matrix former, microcrystalline cellulose as a filler and disodium phosphate anhydrous and trisodium phosphate dodecahydrate as alkalizing materials. Water and a water-ethanol mixture served as granulation liquids. Pellet formation was evaluated via mechanical, dissolution and morphological studies. In order to enhance the dissolution of Atenolol from the pellets, alkalizing components were used and the influence of these components on the pH was tested. Investigations of the breaking hardness, the morphology and the dissolution revealed that the pellets containing trisodium phosphate dodecahydrate and prepared with a higher amount of water as binding liquid displayed the best physico-chemical parameters and uniform dissolution. In in vitro experiments, the dissolution release complied with the texture of the pellets and the effect of pH. The pellets have suitable shape and very good hardness for the coating process and are appropriate for subsequent in vivo experiments.

  14. Pelletized Asphalt for Airfield Damage Repair

    DTIC Science & Technology

    2009-08-01

    HD) design is based on the 75-blow Marshall Hammer and utilizes air voids (Va) and voids filled with asphalt (VFA) as criteria for establishing... flowable ); however, these additives pose their own unique problems. For instance, when sulfur is used to stiffen the binder, it has a tendency to...pellets during the manufacturing process. These fines fill the interstices between the pellets and eliminate the point contact thus creating a

  15. Single pellet crush strength testing of catalysts

    SciTech Connect

    Brienza, P.K. )

    1988-09-01

    ASTM D-32 Committee on Catalysts has developed a standard test method for single pellet crush strength for formed catalyst shapes. This standard was issued under the fixed designation D 4179. The method is applicable to regular catalyst shapes such as tablets and spheres. Extrudates, granular materials, and other irregular shapes are excluded. The committee continues to work on the development of a method for the single pellet crush testing of extrudates.

  16. Pelletization process of postproduction plant waste

    NASA Astrophysics Data System (ADS)

    Obidziński, S.

    2012-07-01

    The results of investigations on the influence of material, process, and construction parameters on the densification process and density of pellets received from different mixtures of tobacco and fine-grained waste of lemon balm are presented. The conducted research makes it possible to conclude that postproduction waste eg tobacco and lemon balm wastes can be successfully pelletized and used as an ecological, solid fuels.

  17. Gas adsorption capacity of wood pellets

    DOE PAGES

    Yazdanpanah, F.; Sokhansanj, Shahabaddine; Lim, C. Jim; ...

    2016-02-03

    In this paper, temperature-programmed desorption (TPD) analysis was used to measure and analyze the adsorption of off-gases and oxygen by wood pellets during storage. Such information on how these gases interact with the material helps in the understanding of the purging/stripping behavior of off-gases to develop effective ventilation strategies for wood pellets. Steam-exploded pellets showed the lowest carbon dioxide (CO2) uptake compared to the regular and torrefied pellets. The high CO2 adsorption capacity of the torrefied pellets could be attributed to their porous structure and therefore greater available surface area. Quantifying the uptake of carbon monoxide by pellets was challengingmore » due to chemical adsorption, which formed a strong bond between the material and carbon monoxide. The estimated energy of desorption for CO (97.8 kJ/mol) was very high relative to that for CO2 (7.24 kJ/mol), demonstrating the mechanism of chemical adsorption and physical adsorption for CO and CO2, respectively. As for oxygen, the strong bonds that formed between the material and oxygen verified the existence of chemical adsorption and formation of an intermediate material.« less

  18. Gas adsorption capacity of wood pellets

    SciTech Connect

    Yazdanpanah, F.; Sokhansanj, Shahabaddine; Lim, C. Jim; Lau, A.; Bi, X. T.

    2016-02-03

    In this paper, temperature-programmed desorption (TPD) analysis was used to measure and analyze the adsorption of off-gases and oxygen by wood pellets during storage. Such information on how these gases interact with the material helps in the understanding of the purging/stripping behavior of off-gases to develop effective ventilation strategies for wood pellets. Steam-exploded pellets showed the lowest carbon dioxide (CO2) uptake compared to the regular and torrefied pellets. The high CO2 adsorption capacity of the torrefied pellets could be attributed to their porous structure and therefore greater available surface area. Quantifying the uptake of carbon monoxide by pellets was challenging due to chemical adsorption, which formed a strong bond between the material and carbon monoxide. The estimated energy of desorption for CO (97.8 kJ/mol) was very high relative to that for CO2 (7.24 kJ/mol), demonstrating the mechanism of chemical adsorption and physical adsorption for CO and CO2, respectively. As for oxygen, the strong bonds that formed between the material and oxygen verified the existence of chemical adsorption and formation of an intermediate material.

  19. Simulation of reduction of iron-oxide-carbon composite pellets in a rotary hearth furnace

    NASA Astrophysics Data System (ADS)

    Halder, Sabuj

    The primary motivation of this work is to evaluate a new alternative ironmaking process which involves the combination of a Rotary Hearth Furnace (RHF) with an iron bath smelter. This work is concerned primarily, with the productivity of the RHF. It is known that the reduction in the RHF is controlled by chemical kinetics of the carbon oxidation and wustite reduction reactions as well as by heat transfer to the pellet surface and within the pellet. It is heat transfer to the pellet which limits the number of layers of pellets in the pellet bed in the RHF and thus, the overall productivity. Different types of carbon like graphite, coal-char and wood charcoal were examined. Part of the research was to investigate the chemical kinetics by de-coupling it from the influence of heat and mass transfer. This was accomplished by carrying out reduction experiments using small iron-oxide-carbon powder composite mixtures. The reaction rate constants were determined by fitting the experimental mass loss with a mixed reaction model. This model accounts for the carbon oxidation by CO2 and wustite reduction by CO, which are the primary rate controlling surface-chemical reactions in the composite system. The reaction rate constants have been obtained using wustite-coal-char powder mixtures and wustite-wood-charcoal mixtures. The wustite for these mixtures was obtained from two iron-oxide sources: artificial porous analytical hematite (PAH) and hematite ore tailings. In the next phase of this study, larger scale experiments were conducted in a RHF simulator using spherical composite pellets. Measurement of the reaction rates was accomplished using off-gas analysis. Different combinations of raw materials for the pellets were investigated. These included artificial ferric oxide as well as naturally existing hematite and taconite ores. Graphite, coal-char and wood-charcoal were the reductants. Experiments were conducted using a single layer, a double layer and a triple layer of

  20. Injection of CO2-saturated water through a siliceous sandstone plug from the Hontomin test site (Spain): experiment and modeling.

    PubMed

    Canal, J; Delgado, J; Falcón, I; Yang, Q; Juncosa, R; Barrientos, V

    2013-01-02

    Massive chemical reactions are not expected when injecting CO(2) in siliceous sandstone reservoirs, but their performance can be challenged by small-scale reactions and other processes affecting their transport properties. We have conducted a core flooding test with a quartzarenite plug of Lower Cretaceous age representative of the secondary reservoir of the Hontomín test site. The sample, confined at high pressure, was successively injected with DIW and CO(2)-saturated DIW for 49 days while monitoring geophysical, chemical, and hydrodynamic parameters. The plug experienced little change, without evidence of secondary carbonation. However, permeability increased by a factor of 4 (0.022-0.085 mD), and the V(P)/V(S) ratio, whose change is related with microcracking, rose from ~1.68 to ~1.8. Porosity also increased (7.33-8.1%) from the beginning to the end of the experiment. Fluid/rock reactions were modeled with PHREEQC-2, and they are dominated by the dissolution of Mg-calcite. Mass balances show that ~4% of the initial carbonate was consumed. The results suggest that mineral dissolution and microcracking may have acted in a synergistic way at the beginning of the acidic flooding. However, dissolution processes concentrated in pore throats can better explain the permeability enhancement observed over longer periods of time.

  1. Paper 58714 - Exploring activated faults hydromechanical processes from semi-controled field injection experiments

    NASA Astrophysics Data System (ADS)

    Guglielmi, Y.; Cappa, F.; Nussbaum, C.

    2015-12-01

    The appreciation of the sensitivity of fractures and fault zones to fluid-induced-deformations in the subsurface is a key question in predicting the reservoir/caprock system integrity around fluid manipulations with applications to reservoir leakage and induced seismicity. It is also a question of interest in understanding earthquakes source, and recently the hydraulic behavior of clay faults under a potential reactivation around nuclear underground depository sites. Fault and fractures dynamics studies face two key problems (1) the up-scaling of laboratory determined properties and constitutive laws to the reservoir scale which is not straightforward when considering faults and fractures heterogeneities, (2) the difficulties to control both the induced seismicity and the stimulated zone geometry when a fault is reactivated. Using instruments dedicated to measuring coupled pore pressures and deformations downhole, we conducted field academic experiments to characterize fractures and fault zones hydromechanical properties as a function of their multi-scale architecture, and to monitor their dynamic behavior during the earthquake nucleation process. We show experiments on reservoir or cover rocks analogues in underground research laboratories where experimental conditions can be optimized. Key result of these experiments is to highlight how important the aseismic fault activation is compared to the induced seismicity. We show that about 80% of the fault kinematic moment is aseismic and discuss the complex associated fault friction coefficient variations. We identify that the slip stability and the slip velocity are mainly controlled by the rate of the permeability/porosity increase, and discuss the conditions for slip nucleation leading to seismic instability.

  2. Impact of lithium pellets on plasma performance in the ASDEX Upgrade all-metal-wall tokamak

    NASA Astrophysics Data System (ADS)

    Lang, P. T.; Maingi, R.; Mansfield, D. K.; McDermott, R. M.; Neu, R.; Wolfrum, E.; Arredondo Parra, R.; Bernert, M.; Birkenmeier, G.; Diallo, A.; Dunne, M.; Fable, E.; Fischer, R.; Geiger, B.; Hakola, A.; Nikolaeva, V.; Kappatou, A.; Laggner, F.; Oberkofler, M.; Ploeckl, B.; Potzel, S.; Pütterich, T.; Sieglin, B.; Szepesi, T.; ASDEX Upgrade Team

    2017-01-01

    The impact of lithium (Li) on plasma performance was investigated at the ASDEX Upgrade tokamak, which features a full tungsten wall. Li pellets containing 1.6  ×  1020 Li atoms were launched with a speed of 600 m s-1 to achieve deep penetration into the plasma and minimize the impact on the first wall. Homogeneous transient Li concentrations in the plasma of up to 15% were established. The Li sustainment time in the plasma decreased with an increasing heating power from 150 to 40 ms. Due to the pellet rate being restricted to 2 Hz, no Li pile-up could take place. No significant positive impact on plasma properties, as reported from other tokamak devices, could be found; the Li pellets rather caused a small reduction in plasma energy, mainly due to enhanced radiation. Due to pellet injection, a short-lived Li layer was formed on the plasma-facing components, which lasted a few discharges and led to moderately beneficial effects during plasma start-up. Most pellets were found to trigger type-I ELMs, either by their direct local perturbation or indirectly by the altered edge conditions; however, reliability was less than 100%.

  3. Properties of melt extruded enteric matrix pellets.

    PubMed

    Schilling, Sandra U; Shah, Navnit H; Waseem Malick, A; McGinity, James W

    2010-02-01

    The objective of this study was to investigate the properties of enteric matrix pellets that were prepared by hot-melt extrusion in a one-step, continuous process. Five polymers (Eudragit) L100-55, L100 and S100, Aqoat grades LF and HF) were investigated as possible matrix formers, and pellets prepared with Eudragit S100 demonstrated superior gastric protection and acceptable processibility. Extruded pellets containing Eudragit S100 and up to 40% theophylline released less than 10% drug over 2h in acid, however, the processibility and yields were compromised by the high amounts of the non-melting drug material in the formulation. Efficient plasticization of Eudragit S100 was necessary to reduce the polymer's glass transition temperature and melt viscosity. Five compounds including triethyl citrate, methylparaben, polyethylene glycol 8000, citric acid monohydrate and acetyltributyl citrate were investigated in terms of plasticization efficiency and preservation of the delayed drug release properties. The aqueous solubility of the plasticizer and its plasticization efficiency impacted the drug release rate from the matrix pellets. The use of water-soluble plasticizers resulted in a loss of gastric protection, whereas low drug release rates in acid were found for pellets containing insoluble plasticizers or no plasticizer, independent of the extent of Eudragit S100 plasticization. The release rate of theophylline in buffer pH 7.4 was faster for pellets that were prepared with efficient plasticizers. The microstructure and solid-state properties of plasticized pellets were further investigated by scanning electron microscopy and powder X-ray diffraction. Pellets prepared with efficient plasticizers (TEC, methylparaben, PEG 8000) exhibited matrices of low porosity, and the drug was homogeneously dispersed in its original polymorphic form. Pellets containing ATBC or citric acid monohydrate had to be extruded at elevated temperature and showed physical instabilities in

  4. Ultrasonic vibration-assisted (UV-A) pelleting of wheat straw: a constitutive model for pellet density.

    PubMed

    Song, Xiaoxu; Zhang, Meng; Pei, Z J; Wang, Donghai

    2015-07-01

    Ultrasonic vibration-assisted (UV-A) pelleting can increase cellulosic biomass density and reduce biomass handling and transportation costs in cellulosic biofuel manufacturing. Effects of input variables on pellet density in UV-A pelleting have been studied experimentally. However, there are no reports on modeling of pellet density in UV-A pelleting. Furthermore, in the literature, most reported density models in other pelleting methods of biomass are empirical. This paper presents a constitutive model to predict pellet density in UV-A pelleting. With the predictive model, relations between input variables (ultrasonic power and pelleting pressure) and pellet density are predicted. The predicted relations are compared with those determined experimentally in the literature. Model predictions agree well with reported experimental results.

  5. Experiments on opposed lateral jets injected into swirling crossflow. M.S. Thesis Final Report

    NASA Technical Reports Server (NTRS)

    Mcmurry, C. B.; Lilley, D. G.

    1986-01-01

    Experiments have been conducted to obtain the time-mean and turbulent quantities of opposed lateral jets in a low speed, nonreacting flowfield. A jet-to-crossflow velocity ratio of R = v sub J/u sub 0 = 4 was used throughout the experiments, with swirl vane angles of d = 0 (swirler removed), 45 and 70 deg used with the crossflow. Flow visualization techniques used were neutrally-buoyant helium-filled soap bubbles and multispark photography in order to obtain the gross flowfield characteristics. Measurements of time-mean and turbulent quantities were obtained utilizing a six-orientation single hot-wire technique. For the nonswirling case, the jets were found not to penetrate past the test-section centerline, in contrast to the single lateral jet with the same jet-to-crossflow velocity ratio. In the swirling cases, the crossflow remains in a narrow region near the wall of the test section. The opposed jets are swept from their vertical courses into spiral trajectories close to the confining walls. Extensive results are presented in r-x plane plots.

  6. Polarization Issues with High Power Injection and Low Power Emission in Fusion Experiments

    SciTech Connect

    Goodman, T. P.; Felici, F.; Udintsev, V. S.

    2009-11-26

    All tokamak experiments using ECCD require setting of the beam elliptical polarization for proper coupling to the plasma. This is done either in the matching optics unit (MOU) at the output of the gyrotron, or in a couple of miter bends of the transmission line. Similarly, oblique ECE receivers require selection of the correct elliptical polarization to provide localized measurements. For the TCV tokamak at the CRPP, gyrotron and oblique-ECE polarizers are characterized during either high- or low- power testing of equipment: for the gyrotrons the behaviour is determined at a single frequency, but for the oblique-ECE the broadband response is needed. These characteristics are included in the calibration database and used during subsequent analysis of the power coupling to, or from, the sources (gyrotron, plasma, or low power transmitting antenna). A more detailed characterization has been carried out (at low power) with the MOU for the EU, 170 GHz, 2 MW, gyrotron prototype for ITER. This paper discusses the methodology and results of these measurements, as well as a review of nearly a decade's worth of experimental data from the 6 gyrotron, 3 MW, 82.6 GHz TCV system. In particular, the consistency between the calibrations and the subsequent data from tokamak experiments is analysed.

  7. Demonstration of Tokamak ohmic flux saving by transient coaxial helicity injection in the national spherical torus experiment.

    PubMed

    Raman, R; Mueller, D; Nelson, B A; Jarboe, T R; Gerhardt, S; Kugel, H W; Leblanc, B; Maingi, R; Menard, J; Ono, M; Paul, S; Roquemore, L; Sabbagh, S; Soukhanovskii, V

    2010-03-05

    Transient coaxial helicity injection (CHI) started discharges in the National Spherical Torus Experiment (NSTX) have attained peak currents up to 300 kA and when coupled to induction, it has produced up to 200 kA additional current over inductive-only operation. CHI in NSTX has shown to be energetically quite efficient, producing a plasma current of about 10 A/J of capacitor bank energy. In addition, for the first time, the CHI-produced toroidal current that couples to induction continues to increase with the energy supplied by the CHI power supply at otherwise similar values of the injector flux, indicating the potential for substantial current generation capability by CHI in NSTX and in future toroidal devices.

  8. The AGS new fast extraction system for the g-2 experiment and RHIC injection

    SciTech Connect

    Tanaka, M.; Lee, Y.Y.

    1991-01-01

    The AGS requires a new fast extraction beam (NewFEB) system for the muon g-2 experiment and the Relativistic Heavy Ion Collider (RHIC). The proposed NewFEB system will consist of a new fast multi-pulsing kicker placed at straight section G10 and an ejector septum magnet at H10, together will local orbit bumps generated by powering backleg windings on the AGS main magnets. The new system is capable of performing single bunch multiple extraction as often as every 8 ms up to 12 times per AGS cycle, in addition to the standard single turn fast extraction. The conceptual design of the NewFEB system will be discussed. 3 refs., 3 figs., 1 tab.

  9. The External-Injection experiment at the SPARC_LAB facility

    NASA Astrophysics Data System (ADS)

    Rossi, Andrea R.; Bacci, Alberto; Belleveglia, Marco; Chiadroni, Enrica; Cianchi, Alessandro; Di Pirro, Giampiero; Ferrario, Massimo; Gallo, Alessandro; Gatti, Giancarlo; Maroli, Cesare; Mostacci, Andrea; Petrillo, Vittoria; Serafini, Luca; Tomassini, Paolo; Vaccarezza, Cristina

    2014-03-01

    At the SPARC_LAB facility of INFN-LNF we are installing a transport lines for ultra-short electron bunches and another for ultra-intense laser pulses, generated by the SPARC photo-injector and by the FLAME laser in a synchronized fashion at the tens of fs level, to co-propagate inside a hydrogen filled glass capillary, in order to perform acceleration of the electron bunch by a plasma wave driven by the laser pulse. The main aim of this experiment is to demonstrate that a high brightness electron beam can be accelerated by a plasma wave without any significant degradation of its quality. Motivations of the technical choices are made and expected performances are reported.

  10. A 400-pellet feed system for the ORNL centrifuge pellet injector

    SciTech Connect

    Foster, C.A.; Qualls, A.L.; Baylor, L.R.; Schechter, D.E.; Dyer, G.R.; Milora, S.L.

    1993-11-01

    An improved and extended pellet fabrication and feed mechanism is being developed for the Oak Ridge National Laboratory (ORNL) centrifuge pellet injector that is presently installed on Tore Supra. This upgrade will extend the number of pellets available for a single-plasma discharge from 100 to 400. In addition, a new pusher and delivery system is expected to improve the performance of the device. As in the original system, deuterium ice is deposited from the gas phase on a liquid-helium-cooled rotating disk, forming a rim of solid deuterium. The rim of ice is machined to a parabolic profile from which pellets are pushed. In the new device, a stack of four ice rims are formed simultaneously, thereby increasing the capacity from 100 to 400 pellets. An improved method of ice formation has also been developed that produces clear ice. The pellet pusher and delivery system utilizes a four-axis, brushless dc servo system to precisely cut and deliver the pellets from the ice rim to the entrance of the centrifuge wheel. Pellets can be formed with sizes ranging from 2.5- to 4-mm diam at a rate of up to 8 per second. The operation of the injector is fully automated by a computer control system. The design and test results of the device are reported.

  11. The influence of formulation variables on the properties of pellets containing a self-emulsifying mixture.

    PubMed

    Newton, M; Petersson, J; Podczeck, F; Clarke, A; Booth, S

    2001-08-01

    A method of converting self-emulsifying drug delivery systems to a pellet form has been studied. Formulations with varied relative quantities of an oil/surfactant mixture, water, microcrystalline cellulose (MCC), and lactose were chosen in a statistical design after preliminary ranging experiments. Pellets were produced by extrusion/spheronization. The characteristics of the pellets were studied by sieving, disintegration testing, diametral compression, image analysis, non-contact laser profilometry, and scanning electron microscopy. The effects of the formulation variables on pellet properties were evaluated by analysis of variance. It was possible to relate the formulation variables to all the quantified pellet properties except the shape. The relative quantities of oil/surfactant and water had an effect on the amount of liquid and oil/surfactant that could be incorporated into the powder, extrusion force, median diameter, size spread, disintegration time, tensile strength, and surface roughness. The relative quantities of lactose and MCC had an effect on the amount of liquid and oil/surfactant that could be incorporated into the powder, tensile strength, and roughness only. Water was an essential element of the formulations. The maximum quantity of the specific oil/surfactant combination studied that can be incorporated was 42% of the dry pellet weight.

  12. Uranium silicide pellet fabrication by powder metallurgy for accident tolerant fuel evaluation and irradiation

    SciTech Connect

    Harp, Jason Michael; Lessing, Paul Alan; Hoggan, Rita Elaine

    2015-06-21

    In collaboration with industry, Idaho National Laboratory is investigating uranium silicide for use in future light water reactor fuels as a more accident resistant alternative to uranium oxide base fuels. Specifically this project was focused on producing uranium silicide (U3Si2) pellets by conventional powder metallurgy with a density greater than 94% of the theoretical density. This work has produced a process to consistently produce pellets with the desired density through careful optimization of the process. Milling of the U3Si2 has been optimized and high phase purity U3Si2 has been successfully produced. Results are presented from sintering studies and microstructural examinations that illustrate the need for a finely ground reproducible particle size distribution in the source powder. The optimized process was used to produce pellets for the Accident Tolerant Fuel-1 irradiation experiment. The average density of these pellets was 11.54 ±0.06 g/cm3. Additional characterization of the pellets by scaning electron microscopy and X-ray diffraction has also been performed. As a result, pellets produced in this work have been encapsulated for irradiation, and irradiation in the Advanced Test Reactor is expected soon.

  13. Uranium silicide pellet fabrication by powder metallurgy for accident tolerant fuel evaluation and irradiation

    NASA Astrophysics Data System (ADS)

    Harp, Jason M.; Lessing, Paul A.; Hoggan, Rita E.

    2015-11-01

    In collaboration with industry, Idaho National Laboratory is investigating uranium silicide for use in future light water reactor fuels as a more accident resistant alternative to uranium oxide base fuels. Specifically this project was focused on producing uranium silicide (U3Si2) pellets by conventional powder metallurgy with a density greater than 94% of the theoretical density. This work has produced a process to consistently produce pellets with the desired density through careful optimization of the process. Milling of the U3Si2 has been optimized and high phase purity U3Si2 has been successfully produced. Results are presented from sintering studies and microstructural examinations that illustrate the need for a finely ground reproducible particle size distribution in the source powder. The optimized process was used to produce pellets for the Accident Tolerant Fuel-1 irradiation experiment. The average density of these pellets was 11.54 ± 0.06 g/cm3. Additional characterization of the pellets by scanning electron microscopy and X-ray diffraction has also been performed. Pellets produced in this work have been encapsulated for irradiation, and irradiation in the Advanced Test Reactor is expected soon.

  14. Uranium silicide pellet fabrication by powder metallurgy for accident tolerant fuel evaluation and irradiation

    DOE PAGES

    Harp, Jason Michael; Lessing, Paul Alan; Hoggan, Rita Elaine

    2015-06-21

    In collaboration with industry, Idaho National Laboratory is investigating uranium silicide for use in future light water reactor fuels as a more accident resistant alternative to uranium oxide base fuels. Specifically this project was focused on producing uranium silicide (U3Si2) pellets by conventional powder metallurgy with a density greater than 94% of the theoretical density. This work has produced a process to consistently produce pellets with the desired density through careful optimization of the process. Milling of the U3Si2 has been optimized and high phase purity U3Si2 has been successfully produced. Results are presented from sintering studies and microstructural examinationsmore » that illustrate the need for a finely ground reproducible particle size distribution in the source powder. The optimized process was used to produce pellets for the Accident Tolerant Fuel-1 irradiation experiment. The average density of these pellets was 11.54 ±0.06 g/cm3. Additional characterization of the pellets by scaning electron microscopy and X-ray diffraction has also been performed. As a result, pellets produced in this work have been encapsulated for irradiation, and irradiation in the Advanced Test Reactor is expected soon.« less

  15. Injection device-related risk management toward safe administration of medications: experience in a university teaching hospital in The People’s Republic of China

    PubMed Central

    Zhu, Ling-ling; Li, Wei; Song, Ping; Zhou, Quan

    2014-01-01

    The use of injection devices to administer intravenous or subcutaneous medications is common practice throughout a variety of health care settings. Studies suggest that one-half of all harmful medication errors originate during drug administration; of those errors, about two-thirds involve injectables. Therefore, injection device management is pivotal to safe administration of medications. In this article, the authors summarize the relevant experiences by retrospective analysis of injection device-related near misses and adverse events in the Second Affiliated Hospital of Zhejiang University, School of Medicine, Zhejiang University, People’s Republic of China. Injection device-related near misses and adverse events comprised the following: 1) improper selection of needle diameter for subcutaneous injection, material of infusion sets, and pore size of in-line filter; 2) complications associated with vascular access; 3) incidents induced by absence of efficient electronic pump management and infusion tube management; and 4) liquid leakage of chemotherapeutic infusion around the syringe needle. Safe injection drug use was enhanced by multidisciplinary collaboration, especially among pharmacists and nurses; drafting of clinical pathways in selection of vascular access; application of approaches such as root cause analysis using a fishbone diagram; plan–do–check–act and quality control circle; and construction of a culture of spontaneous reporting of near misses and adverse events. Pharmacists must be professional in regards to medication management and use. The depth, breadth, and efficiency of cooperation between nurses and pharmacists are pivotal to injection safety. PMID:24669192

  16. Injection device-related risk management toward safe administration of medications: experience in a university teaching hospital in The People's Republic of China.

    PubMed

    Zhu, Ling-Ling; Li, Wei; Song, Ping; Zhou, Quan

    2014-01-01

    The use of injection devices to administer intravenous or subcutaneous medications is common practice throughout a variety of health care settings. Studies suggest that one-half of all harmful medication errors originate during drug administration; of those errors, about two-thirds involve injectables. Therefore, injection device management is pivotal to safe administration of medications. In this article, the authors summarize the relevant experiences by retrospective analysis of injection device-related near misses and adverse events in the Second Affiliated Hospital of Zhejiang University, School of Medicine, Zhejiang University, People's Republic of China. Injection device-related near misses and adverse events comprised the following: 1) improper selection of needle diameter for subcutaneous injection, material of infusion sets, and pore size of in-line filter; 2) complications associated with vascular access; 3) incidents induced by absence of efficient electronic pump management and infusion tube management; and 4) liquid leakage of chemotherapeutic infusion around the syringe needle. Safe injection drug use was enhanced by multidisciplinary collaboration, especially among pharmacists and nurses; drafting of clinical pathways in selection of vascular access; application of approaches such as root cause analysis using a fishbone diagram; plan-do-check-act and quality control circle; and construction of a culture of spontaneous reporting of near misses and adverse events. Pharmacists must be professional in regards to medication management and use. The depth, breadth, and efficiency of cooperation between nurses and pharmacists are pivotal to injection safety.

  17. Intrathecal Injections in Children With Spinal Muscular Atrophy: Nusinersen Clinical Trial Experience.

    PubMed

    Haché, Manon; Swoboda, Kathryn J; Sethna, Navil; Farrow-Gillespie, Alan; Khandji, Alexander; Xia, Shuting; Bishop, Kathie M

    2016-06-01

    Nusinersen (ISIS-SMNRx or ISIS 396443) is an antisense oligonucleotide drug administered intrathecally to treat spinal muscular atrophy. We summarize lumbar puncture experience in children with spinal muscular atrophy during a phase 1 open-label study of nusinersen and its extension. During the studies, 73 lumbar punctures were performed in 28 patients 2 to 14 years of age with type 2/3 spinal muscular atrophy. No complications occurred in 50 (68%) lumbar punctures; in 23 (32%) procedures, adverse events were attributed to lumbar puncture. Most common adverse events were headache (n = 9), back pain (n = 9), and post-lumbar puncture syndrome (n = 8). In a subgroup analysis, adverse events were more frequent in older children, children with type 3 spinal muscular atrophy, and with a 21- or 22-gauge needle compared to a 24-gauge needle or smaller. Lumbar punctures were successfully performed in children with spinal muscular atrophy; lumbar puncture-related adverse event frequency was similar to that previously reported in children.

  18. Problems Caused by Microbes and Treatment Strategies The Effect of Nitrate Injection in Oil Reservoirs - Experience with Nitrate Injection in the Halfdan Oilfield

    NASA Astrophysics Data System (ADS)

    Larsen, Jan; Skovhus, Torben Lund

    This chapter deals with the use of nitrate injection for reservoir souring mitigation in an oilfield with seawater injection in the Danish sector of the North Sea. Nitrate impacts on the activity of sulphate-reducing bacteria (SRB) and biofilm redox potential (Larsen et al., 2007), as a result of which corrosion due to SRB activity will be reduced, souring inhibited and previously formed sulphide removed (Larsen, 2002). One important aspect is that the microbiological reduction of nitrate provides approximately three times more energy to SRB than the reduction of sulphate. Therefore, when both nitrate and sulphate are present, nitrate becomes the preferred electron acceptor and SRB capable of growing on nitrate will dominate. Nitrate provides a competitive advantage to nitrate-utilising bacteria (indicated by the general acronym NUB) during competition for available carbon sources as the NUB are capable of much faster growth than SRB.

  19. EMC3-EIRENE modelling of toroidally-localized divertor gas injection experiments on Alcator C-Mod

    DOE PAGES

    Lore, Jeremy D.; Reinke, M. L.; LaBombard, Brian; ...

    2014-09-30

    Experiments on Alcator C-Mod with toroidally and poloidally localized divertor nitrogen injection have been modeled using the three-dimensional edge transport code EMC3-EIRENE to elucidate the mechanisms driving measured toroidal asymmetries. In these experiments five toroidally distributed gas injectors in the private flux region were sequentially activated in separate discharges resulting in clear evidence of toroidal asymmetries in radiated power and nitrogen line emission as well as a ~50% toroidal modulation in electron pressure at the divertor target. The pressure modulation is qualitatively reproduced by the modelling, with the simulation yielding a toroidal asymmetry in the heat flow to the outermore » strike point. Finally, toroidal variation in impurity line emission is qualitatively matched in the scrape-off layer above the strike point, however kinetic corrections and cross-field drifts are likely required to quantitatively reproduce impurity behavior in the private flux region and electron temperatures and densities directly in front of the target.« less

  20. Extended Magnetohydrodynamic Simulations of the Helicity Injected Torus (HIT-SI) Spheromak Experiment with the NIMROD Code

    NASA Astrophysics Data System (ADS)

    Akcay, Cihan

    A comparative study of 3-D pressureless resistive (single-fluid) magnetohydrodynamic (rMHD) and 3-D pressureless two-fluid magnetohydrodynamic (2fl-MHD) models of the Helicity Injected Torus experiment (HIT-SI) is presented. HIT-SI is a spheromak current-drive experiment that uses two geometrically asymmetric helicity injectors to generate and sustain toroidal plasmas. The goal of the experiment is to demonstrate that steady inductive helicity injection (SIHI) is a viable method for driving and sustaining a magnetized plasma for the eventual purpose of electricity production with magnetic fusion power. The experiment has achieved sustainment of nearly 100 kA of plasma current for ˜1~ms. Fusion power plants are expected to sustain a burning plasma for many minutes to hours with more than 10~MA of plasma current. The purpose of project is to determine the validity of the single-fluid and two-fluid MHD models of HIT-SI. The comparable size of the collisionless ion skin depth to the diameter of the injectors and resistive skin depth predicates the importance of two-fluid effects. The simulations are run with NIMROD (non-ideal magnetohydrodynamics code with rotation-open discussion), an initial-value, 3-D extended MHD code. A constant and uniform plasma density and temperature are assumed. The helicity injectors are modeled as oscillating normal magnetic and parallel electric field boundary conditions. The simulations use parameters that closely match those of the experiment. The simulation output is compared to the formation time, plasma current, and internal and surface magnetic fields. Results of the study indicate 2fl-MHD shows quantitative agreement with the experiment while rMHD only captures the qualitative features. The validity of each model is assessed based on how accurately it reproduces the global quantities as well as the temporal and spatial dependence of the measured magnetic fields. 2fl-MHD produces the current amplification and formation time

  1. Tritium pellet injector design for tokamak fusion test reactor

    SciTech Connect

    Fisher, P.W.; Baylor, L.R.; Bryan, W.E.; Combs, S.K.; Easterly, C.E.; Lunsford, R.V.; Milora, S.L.; Schuresko, D.D.; White, J.A.; Williamson, D.H.

    1985-01-01

    A tritium pellet injector (TPI) system has been designed for the Tokamak Fusion Test Reactor (TFTR) Q approx. 1 phase of operation. The injector gun utilizes a radial design with eight independent barrels and a common extruder to minimize tritium inventory. The injection line contains guide tubes with intermediate vacuum pumping stations and fast valves to minimize propellant leakage to the torus. The vacuum system is designed for tritium compatibility. The entire injector system is contained in a glove box for secondary containment protection against tritium release. Failure modes and effects have been analyzed, and structural analysis has been performed for most intense predicted earthquake conditions. Details of the design and operation of this system are presented in this paper.

  2. National Steel Pellet Company`s secondary grinding circuit modifications

    SciTech Connect

    Wennen, J.E.; Nordstrom, W.J.; Murr, D.L.

    1996-12-31

    National Steel Pellet Company (NSPC) conducted pilot scale testing and computer simulation studies which indicates that the capacity of the secondary grinding mill could be increased and that concentrate grade improvement could be expected with improved classification in the grinding circuit. Based on these studies, a decision was made to modify one secondary ball mill line at NSPC to include both cyclone and screen classification with magnetic separation applied to the circulating load. This paper will briefly discuss the studies leading to the decision to modify the circuit, the design of the modified circuit and the initial start-up and operating experience.

  3. Pellet ablation and ablation model development

    SciTech Connect

    Houlberg, W.A.

    1989-01-01

    A broad survey of pellet ablation is given, based primarily on information presented at this meeting. The implications of various experimental observations for ablation theory are derived from qualitative arguments of the physics involved. The major elements of a more complete ablation theory are then outlined in terms of these observations. This is followed by a few suggestions on improving the connections between theory and experimental results through examination of ablation data. Although this is a rather aggressive undertaking for such a brief (and undoubtedly incomplete) assessment, some of the discussion may help us advance the understanding of pellet ablation. 17 refs.

  4. CO{sub 2} pellet blasting studies

    SciTech Connect

    Archibald, K.E.

    1997-01-01

    Initial tests with CO{sub 2} pellet blasting as a decontamination technique were completed in 1993 at the Idaho Chemical Processing Plant (ICPP) at the Idaho National Engineering Laboratory (INEL). During 1996, a number of additional CO{sub 2} pellet blasting studies with Alpheus Cleaning Technologies, Oak Ridge National Laboratory, and Pennsylvania State University were conducted. After the testing with Alpheus was complete, an SDI-5 shaved CO{sub 2} blasting unit was purchased by the ICPP to test and determine its capabilities before using in ICPP decontamination efforts. Results of the 1996 testing will be presented in this report.

  5. International Trade of Wood Pellets (Brochure)

    SciTech Connect

    Not Available

    2013-05-01

    The production of wood pellets has increased dramatically in recent years due in large part to aggressive emissions policy in the European Union; the main markets that currently supply the European market are North America and Russia. However, current market circumstances and trade dynamics could change depending on the development of emerging markets, foreign exchange rates, and the evolution of carbon policies. This fact sheet outlines the existing and potential participants in the wood pellets market, along with historical data on production, trade, and prices.

  6. Feeding soywaste or pellet on performance and carcass characteristics of post-weaning kids.

    PubMed

    Rahman, Mohammad Mijanur; Khadijah, Wan Embong Wan; Abdullah, Ramli Bin

    2016-08-01

    Twelve Jermasia kids were individually housed in pens to study the effects of soywaste on growth performance and carcass characteristics and to compare such effects with commercial pellet. Kids were divided into a pellet group and a soywaste group, including six kids (3 males and 3 females) in each group. Pellet or soywaste was offered to kids at a rate of 2.0 % dry matter (DM) of body weight/day in addition to Napier grass ad libitum. In last 10 days of experiment, kids were housed in metabolism crates for faeces collection. At the end of the experiment, three males from each group were slaughtered. Kids fed soywaste diet consumed more grass and neutral detergent fibre (NDF) than those fed pellet. The same trend was found for the digestibilities of DM, organic matter (OM) and NDF. Conversely, kids fed soywaste diet consumed less soywaste supplement than kids fed pellet. No treatment effects were observed on total intakes of DM, OM and crude protein (CP) including CP digestibility. Similarly, no effects were found on carcass and non-carcass components, except for lean, lean to fat ratio and kidney weight which were higher for kids fed soywaste diet. Results indicate that soywaste is effective as a feed for growing kids.

  7. Effects of pelleting, extrusion, or extrusion and pelleting on energy and nutrient digestibility in diets containing different levels of fiber and fed to growing pigs.

    PubMed

    Rojas, O J; Vinyeta, E; Stein, H H

    2016-05-01

    An experiment was conducted to determine effects of pelleting, extrusion, and extrusion and pelleting on energy and nutrient digestibility in diets containing low, medium, or high concentrations of fiber. Three diets were formulated: 1) the low-fiber diet contained corn and soybean meal; 2) the medium-fiber diet contained corn, soybean meal, and 25% distillers dried grains with solubles (DDGS); and 3) the high-fiber diet contained corn, soybean meal, 25% DDGS, and 20% soybean hulls. Each diet was divided into 4 batches after mixing. One batch was not further processed and was fed in a meal form, one batch was pelleted at 85°C, one batch was extruded at 115°C using a single-screw extruder, and one batch was extruded at 115°C and then pelleted at 85°C. Thus, 12 different diets were produced. Twenty-four growing pigs (26.5 ± 1.5 kg initial BW) had a T-cannula installed in the distal ileum and were allotted to the 12 diets in a split-plot design with 8 pigs allotted to the low-fiber diets, the medium-fiber diets, and the high-fiber diets, respectively. Diets were fed to the pigs during four 14-d periods. Within each type of diet, the 8 pigs were fed the diets produced using the 4 processing technologies. Therefore, there were 8 replicate pigs per diet. Pigs were adjusted to their diets for 14 d before the experiment was initiated. Each of the four 14-d periods consisted of 5 d for adaptation, 5 d of fecal collection according to the marker to marker approach, and ileal digesta were collected on d 13 and 14. Results indicated that pelleting, extrusion, or extrusion and pelleting improved ( < 0.05) the apparent ileal digestibility of starch and most indispensable AA. In most cases, there were no differences between the pelleted, the extruded, and the extruded and pelleted diets. The apparent total tract digestibility of GE was also improved ( < 0.05) by pelleting and by the combination of extrusion and pelleting. The ME of pelleted diets was greater ( < 0.05) than

  8. Looking East on Third Floor of Pellet Plant Including Tops ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking East on Third Floor of Pellet Plant Including Tops of Line One and Blenders One, Two, and Three - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  9. Looking Southeast from Second Floor Mezzanine of Pellet Plant to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southeast from Second Floor Mezzanine of Pellet Plant to Erbia Mixing Area and Poreformer and Acrawax Mixing Station - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  10. The global build-up to intrinsic ELM bursts and comparison with pellet triggered ELMs seen in JET

    NASA Astrophysics Data System (ADS)

    Chapman, S. C.; Dendy, R. O.; Lang, P. T.; Watkins, N. W.; Calderon, F. A.; Romanelli, M.; Todd, T. N.; Contributors, JET

    2017-02-01

    We focus on JET plasmas in which ELMs are triggered by pellets in the presence of ELMs which occur naturally. We perform direct time domain analysis of signals from fast radial field coils and toroidal full flux azimuthal loops. These toroidally integrating signals provide simultaneous high time resolution measurements of global plasma dynamics and its coupling to the control system. We examine the time dynamics of these signals in plasmas where pellet injection is used to trigger ELMs in the presence of naturally occurring ELMs. Pellets whose size and speed are intended to provide maximum local perturbation for ELM triggering are launched at pre-programmed times, without correlation to the occurrence times of intrinsic ELMs. Pellet rates were sufficiently low to prevent sustained changes of the underlying plasma conditions and natural ELM behaviour. We find a global signature of the build-up to natural ELMs in the temporal analytic phase of both the full flux loops and fast radial field coil signals. Before a natural ELM, the signal phases align to the same value on a ˜ 2-5 ms timescale. This global build up to a natural ELM occurs whilst the amplitude of the full flux loop and fast radial field coil signals are at their background value: it precedes the response seen in these signals to the onset of ELMing. In contrast these signals do not clearly phase align before the ELM for ELMs which are the first to occur following pellet injection. This provides a direct test that can distinguish when an ELM is triggered by a pellet as opposed to occurring naturally. It further supports the idea [1-4] of a global build up phase that precedes natural ELMs; pellets can trigger ELMs even when the signal phase is at a value when a natural ELM is unlikely to occur.

  11. Behavioural adaptation of laying hens to dilution of diets under mash and pellet form.

    PubMed

    Vilariño, M; Picard, M L; Melcion, J P; Faure, J M

    1996-12-01

    1. Two laying diets, control (A) and a low-energy (B) diet diluted by adding 450 g/kg wheat bran, were fed to semi-heavy hens in three different forms: mash, small pellets and large pellets. The behavioural adaptations and the production characteristics for these six regimens were studied on 72 individually caged hens, between 19 and 29 weeks of age, subjected to a lighting pattern of 14 h light/24 h. 2. Diet B, as mash, showed a lower apparent physical density than the others. The hardness and durability of the pelleted diets were similar. 3. Hens fed the mash diet B could not completely adjust their food intake to compensate for the dilution and showed reduced egg output and body weight gain compared to the other groups. 4. Video observation of each hen for 14 consecutive hours showed that mash-fed hens ate for longer periods than pellet-fed hens during the first 11 h (proportion of time spent eating: 41.3% mash B, 32.5% mash A and 20% to 25% for all the pelleted diets). These differences were less pronounced during the last 3 h of the photoperiod. 5. Trough-oriented stereotypies were noted in 14 out of 22 mash-fed hens and in 12 out of 47 pellet-fed hens. Dilution of the diet did not appear to exacerbate stereotyped behaviours under the conditions of the study. 6. This experiment demonstrates that the feeding behaviour of laying hens is affected by the physical characteristics of the diet and that this may lower their productivity. 7. Low-energy pelleted diets might be used to feed hens efficiently in tropical countries where cereal by-products are abundant.

  12. Dielectric Properties of Peanut-hull Pellets at Microwave Frequencies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut-hull pellets are obtained from a waste product, peanut-hulls, which after pelleting can have several uses, namely as a renewable fuel. Rapid and nondestructive characterization of peanut-hull pellets is important for industrial utilization of this resource. Properties such as water content an...

  13. Owl Pellet Analysis--A Useful Tool in Field Studies

    ERIC Educational Resources Information Center

    Medlin, G. C.

    1977-01-01

    Describes a technique by which the density and hunting habits of owls can be inferred from their pellets. Owl pellets--usually small, cylindrical packages of undigested bone, hair, etc.--are regurgitated by a roosting bird. A series of activities based on owl pellets are provided. (CP)

  14. Citizen Science International Pellet Watch

    ERIC Educational Resources Information Center

    Dohrenwend, Peter

    2012-01-01

    Like Tokyo, other cities, both small and large, typically have numerous universities with dedicated faculties of scientists. By using portals such as Citizen Science and SciStarter, teachers can reach beyond the four walls of their classroom. The incredible experience of forging a relationship with a local scientist can easily begin via a cordial…

  15. Compositions of volatile organic compounds emitted from melted virgin and waste plastic pellets.

    PubMed

    Yamashita, Kyoko; Yamamoto, Naomichi; Mizukoshi, Atsushi; Noguchi, Miyuki; Ni, Yueyong; Yanagisawa, Yukio

    2009-03-01

    To characterize potential air pollution issues related to recycling facilities of waste plastics, volatile organic compounds (VOCs) emitted from melted virgin and waste plastics pellets were analyzed. In this study, laboratory experiments were performed to melt virgin and waste plastic pellets under various temperatures (150, 200, and 250 degrees C) and atmospheres (air and nitrogen [N2]). In the study presented here, low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS) and the recycled waste plastic pellets were used. The VOCs generated from each plastic pellets were collected by Tenax/Carboxen adsorbent tubes and analyzed by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). The result showed the higher temperatures generated larger amounts of total VOCs (TVOCs). The VOCs emitted from the virgin plastic pellets likely originated from polymer degradation. Smaller TVOC emissions were observed in N2 atmosphere than in air atmosphere. In particular, larger amounts of the oxygenated compounds, which are generally hazardous and malodorous, were detected in air than in N2. In addition to the compounds originating from polymer degradation, the compounds originating from the plastic additives were also detected from LDPE and PS. Furthermore, various species of VOCs likely originating from contaminant inseparate polyvinyl chloride (PVC), food residues, cleaning agents, degreasers, and so on were detected from the waste plastic. Thus, melting waste plastics, as is conducted in recycling facilities, might generate larger amounts of potentially toxic compounds than producing virgin plastics.

  16. Preparation, characterisation and out-of-pile property evaluation of (U,Pu)N fuel pellets

    NASA Astrophysics Data System (ADS)

    Ganguly, C.; Hegde, P. V.; Sengupta, A. K.

    1991-02-01

    (U 0.45Pu 0.55)N and (U 0.8Pu 0.2)N are being considered in India as advanced alternative fuels for the operating fast breeder test reactor (FBTR) and the forthcoming prototype fast breeder reactor (PFBR). Mixed nitride fuel pellets containing <0.1 wt% each of oxygen and carbon impurities were fabricated by the conventional "powder-pellet" (POP) and the advanced "sol-gel microsphere pelletisation" (SGMP) processes, involving two major steps. First, carbothermic reduction of an oxide-graphite powder mixture (in the form of tablets) or gel-microspheres at 1773-1823 K in N 2 followed by N2 + H2 and Ar+ H2 atmospheres. The nitride microspheres could be directly pelletised and sintered to pellets of relatively low density (≤ 85% TD) with an "open" pore structure desirable for LMFBR application. Thermal conductivity and hot hardness of nitride pellets were evaluated up to 1800 and 1500 K respectively. The out-of-pile chemical compatibility experiments of mixed nitride fuel pellets for FBTR with SS 316 cladding at 973 K for 1000 h did not reveal any significant fuel-cladding chemical interaction.

  17. Production of three-dimensional tissue-engineered cartilage through mutual fusion of chondrocyte pellets.

    PubMed

    Hoshi, K; Fujihara, Y; Mori, Y; Asawa, Y; Kanazawa, S; Nishizawa, S; Misawa, M; Numano, T; Inoue, H; Sakamoto, T; Watanabe, M; Komura, M; Takato, T

    2016-09-01

    In this study, the mutual fusion of chondrocyte pellets was promoted in order to produce large-sized tissue-engineered cartilage with a three-dimensional (3D) shape. Five pellets of human auricular chondrocytes were first prepared, which were then incubated in an agarose mold. After 3 weeks of culture in matrix production-promoting medium under 5.78g/cm(2) compression, the tissue-engineered cartilage showed a sufficient mechanical strength. To confirm the usefulness of these methods, a transplantation experiment was performed using beagles. Tissue-engineered cartilage prepared with 50 pellets of beagle chondrocytes was transplanted subcutaneously into the cell-donor dog for 2 months. The tissue-engineered cartilage of the beagles maintained a rod-like shape, even after harvest. Histology showed fair cartilage regeneration. Furthermore, 20 pellets were made and placed on a beta-tricalcium phosphate prism, and this was then incubated within the agarose mold for 3 weeks. The construct was transplanted into a bone/cartilage defect in the cell-donor beagle. After 2 months, bone and cartilage regeneration was identified on micro-computed tomography and magnetic resonance imaging. This approach involving the fusion of small pellets into a large structure enabled the production of 3D tissue-engineered cartilage that was close to physiological cartilage tissue in property, without conventional polyper scaffolds.

  18. Effect of Pellet Coatings on PETN Porosity and Slapper Detonator Efficacy

    NASA Astrophysics Data System (ADS)

    Brown, Kathryn; Haroz, Erik; Brown, Geoff; Monroe, Deirdre

    2015-06-01

    PETN is well known to have a high vapor pressure and tends to sublime when heated. Preliminary experiments suggest that this phenomenon results in increased porosity and may decrease sensitivity to shock initiation by a chip slapper detonator. In this study, PETN pellets were coated on the flyer impact surface with various materials. The pellets were subjected to heating over several days, and the surfaces were analyzed for porosity and recrystallization. We attempted to shock initiate each using a chip slapper detonator, and the timing and voltages required were noted.

  19. Pharmacokinetics and correlation between in vitro release and in vivo absorption of bio-adhesive pellets of panax notoginseng saponins.

    PubMed

    Li, Ying; Zhang, Yun; Zhu, Chun-Yan

    2017-02-01

    The present study was designed to prepare and compare bio-adhesive pellets of panax notoginseng saponins (PNS) with hydroxy propyl methyl cellulose (HPMC), chitosan, and chitosan : carbomer, explore the influence of different bio-adhesive materials on pharmacokinetics behaviors of PNSbio-adhesive pellets, and evaluate the correlation between in vivo absorption and in vitro release (IVIVC). In order to predict the in vivo concentration-time profile by the in vitro release data of bio-adhesive pellets, the release experiment was performed using the rotating basket method in pH 6.8 phosphate buffer. The PNS concentrations in rat plasma were analyzed by HPLC-MS-MS method and the relative bioavailability and other pharmacokinetic parameters were estimated using Kinetica4.4 pharmacokinetic software. Numerical deconvolution method was used to evaluate IVIVC. Our results indicated that, compared with ordinary pellets, PNS bio-adhesive pellets showed increased oral bioavailability by 1.45 to 3.20 times, increased Cmax, and extended MRT. What's more, the release behavior of drug in HPMC pellets was shown to follow a Fickian diffusion mechanism, a synergetic function of diffusion and skeleton corrosion. The in vitro release and the in vivo biological activity had a good correlation, demonstrating that the PNS bio-adhesive pellets had a better sustained release. Numerical deconvolution technique showed the advantage in evaluation of IVIVC for self-designed bio-adhesive pellets with HPMC. In conclusion, the in vitro release data of bio-adhesive pellets with HPMC can predict its concentration-time profile in vivo.

  20. Lethal carbon monoxide poisoning in wood pellet storerooms--two cases and a review of the literature.

    PubMed

    Gauthier, Saskia; Grass, Hildegard; Lory, Martin; Krämer, Thomas; Thali, Michael; Bartsch, Christine

    2012-08-01

    The installation of wood pellet heating as a cost-effective and climatically neutral source of energy for private households has increased steadily in recent years. We report two deaths that occurred within the space of about a year in wood pellet storerooms of private households in German-speaking countries and were investigated by forensic medical teams. This is the first report of fatalities in this special context as is shown in the literature review. Both victims died of carbon monoxide (CO) poisoning; one of the victims was a woman who was 4 months pregnant. Measurements at the scene detected life-threatening CO concentrations (7500 ppm, >500 ppm), which were not significantly reduced after ventilation of the storerooms as required by regulations. We carried out a series of experiments in order to confirm CO production by wood pellets. Thirty kilograms of freshly produced pellets from two different manufacturers were stored for 16 days in airtight containers at 26°C with different relative humidities. CO concentrations between 3100 and 4700 ppm were measured in all containers. There were no notable differences between the wood pellet products or storage at different humidities. Emission of CO from wood pellets has already been described, but fatal accidents have previously been reported only in association with pellet transport on cargo ships or storage in silos. It is therefore a new finding that fatal accidents may also occur in the wood pellet storerooms of private households. We show that significant CO concentrations can build up even when these rooms are ventilated in accordance with the regulations and that such levels may cause the death of healthy persons, as described in the following. As the safety recommendations from the wood pellet industry are inadequate, we consider that further fatal accidents are likely to occur and recommend urgent revision of the safety regulations.

  1. Zirconium carbonitride pellets by internal sol gel and spark plasma sintering as inert matrix fuel material

    NASA Astrophysics Data System (ADS)

    Hedberg, Marcus; Cologna, Marco; Cambriani, Andrea; Somers, Joseph; Ekberg, Christian

    2016-10-01

    Inert matrix fuel is a fuel type where the fissile material is blended with a solid diluent material. In this work zirconium carbonitride microspheres have been produced by internal sol gel technique, followed by carbothermal reduction. Material nitride purities in the produced materials ranged from Zr(N0.45C0.55) to Zr(N0.74C0.26) as determined by X-ray diffraction and application of Vegard's law. The zirconium carbonitride microspheres have been pelletized by spark plasma sintering (SPS) and by conventional cold pressing and sintering. In all SPS experiments cohesive pellets were formed. Maximum final density reached by SPS at 1700 °C was 87% theoretical density (TD) compared to 53% TD in conventional sintering at 1700 °C. Pore sizes in all the produced pellets were in the μm scale and no density gradients could be observed by computer tomography.

  2. CO2 spray mini-injector for digital subtraction angiography versus PC-controlled injection system: experiments in dogs.

    PubMed

    Schmitz-Rode, T; Alzen, G; Günther, R W; Pott, H

    1993-01-01

    A personal computer (PC)-controlled CO2 injector (consisting of a pneumatic unit, electric/electronic system, and calculator) and a spray mini-injector (consisting of a CO2 spray can and a dosage chamber) were used in 10 dogs to determine their efficacy regarding imaging quality and ease of handling. CO2 was injected into the abdominal aorta, renal artery, and femoral artery. The vessel diameter was determined on each CO2 arteriogram and compared with that determined on a reference arteriogram obtained using an iodinated contrast agent. The filling ratio (CO2/iodine) was calculated for each set of injection parameters. Both injection systems provided good visualization (filling ratio > 0.9) of large and small arteries within a range of injection parameters. In terms of practicality, the spray mini-injector is more appealing, because it is easier to handle and does not require any preparation.

  3. Effect of disintegrants on the properties of multiparticulate tablets comprising starch pellets and excipient granules.

    PubMed

    Mehta, Samata; De Beer, Thomas; Remon, Jean Paul; Vervaet, Chris

    2012-01-17

    A design of experiments (DOE) approach (2-level full factorial design) was used to investigate the effect of several formulation and process variables on the properties of fast disintegrating tablets comprising starch-based pellets and excipient granules and to optimize and validate the design space. The percentage of starch pellets (30-50%, w/w), type of disintegrants (Ac-di-sol, Explotab, Polyplasdone), percentage of external disintegrant (4-8%, w/w) and compression force (5-15 kN) were the evaluated factors (24 runs+9 centre points=33 experiments), while tablet hardness, friability and disintegration time were the studied tablet properties (responses). Starch pellets were prepared by extrusion-spheronisation. Excipient granules containing microcrystalline cellulose, lactose, internal disintegrant (8%) and polyvinylpyrrolidone K-30 (4%) were prepared by wet granulation. Pellets, granules (700-1000 μm) and external disintegrant were mixed and compressed into oblong tablets (17.1mm long, 8.2mm wide). Evaluation of the effects calculated from the DOE results showed that a lower concentration of starch pellets and higher compression force were required to yield tablets with a high hardness, a low friability (<1%) and short disintegration time (<3 min). Polyplasdone granules had the lowest porosity and friability which was reflected in the DOE study, where the Polyplasdone-containing tablets were harder, less friable and disintegrated faster compared to Ac-di-sol and Explotab-containing tablets. Monte carlo simulations at the optimal factor settings (30% starch pellets, 4% Polyplasdone and 10 kN compression force) indicated that a robust system was formed as the probability to exceed the limits was low for all responses. Validation of the design space (at optimal settings) showed that the results predicted via the DOE models correlated well with the observed experimental data.

  4. “We don't need services. We have no problems”: exploring the experiences of young people who inject drugs in accessing harm reduction services

    PubMed Central

    Krug, Anita; Hildebrand, Mikaela; Sun, Nina

    2015-01-01

    Introduction Evidence suggests that people who inject drugs often begin their drug use and injecting practices in adolescence, yet there are limited data available on the HIV epidemic and the responses for this population. The comprehensive package of interventions for the prevention, treatment and care of HIV infection among people who inject drugs first laid out in 2009 (revised in 2012) by World Health Organization, United Nations Office of Drugs and Crime and Joint United Nations Programme on HIV/AIDS, does not consider the unique needs of adolescent and young people. In order to better understand the values and preferences of young people who inject drugs in accessing harm reduction services and support, we undertook a series of community consultations with young people with experience of injecting drugs during adolescence. Methods Community consultations (4–14 persons) were held in 14 countries. Participants were recruited using a combined criterion and maximum variation sampling strategy. Data were analyzed using collaborative qualitative data analysis. Frequency analysis of themes was conducted. Results Nineteen community consultations were organized with a total of 132 participants. All participants had experienced injecting drugs before the age of 18. They had the following age distribution: 18–20 (37%), 21–25 (48%) and 26–30 (15%). Of the participants, 73.5% were male while 25.7% were female, with one transgender participant. Barriers to accessing the comprehensive package included: lack of information and knowledge of services, age restrictions on services, belief that services were not needed, fear of law enforcement, fear of stigma, lack of concern, high cost, lack of outreach, lack of knowledge of HCV/TB and lack of youth friendly services. Conclusions The consultations provide a rare insight into the lived experiences of adolescents who inject drugs and highlight the dissonance between their reality and current policy and programmatic

  5. Production of sintered porous metal fluoride pellets

    DOEpatents

    Anderson, L.W.; Stephenson, M.J.

    1973-12-25

    Porous pellets characterized by a moderately reactive crust and a softer core of higher reactivity are produced by forming agglomerates containing a metal fluoride powder and a selected amount ofwater. The metal fluoride is selected to be sinterable and essentially non-reactive with gaseous fluorinating agents. The agglomerates are contacted with a gaseous fluorinating agent under controlled conditions whereby the heat generated by localized reaction of the agent and water is limited to values effccting bonding by localized sintering. Porous pellets composed of cryolite (Na/sub 3/AlF/sub 6/) can be used to selectively remove trace quantities of niobium pentafluoride from a feed gas consisting predominantly of uranium hexafluoride. (Official Gazette)

  6. Design and operation of the pellet charge exchange diagnostic for measurement of energetic confined α particles and tritons on the Tokamak Fusion Test Reactor

    NASA Astrophysics Data System (ADS)

    Medley, S. S.; Mansfield, D. K.; Roquemore, A. L.; Fisher, R. K.; Duong, H. H.; McChesney, J. M.; Parks, P. B.; Petrov, M. P.; Khudoleev, A. V.; Gorelenkov, N. N.

    1996-09-01

    Radially resolved energy and density distributions of the confined α particles in D-T experiments on the Tokamak Fusion Test Reactor (TFTR) are being measured with the pellet charge exchange (PCX) diagnostic. Other energetic ion species can be detected as well, such as tritons produced in D-D plasmas and H, He3, or tritium rf-driven minority ion tails. The ablation cloud formed by injected low-Z impurity pellets provides the neutralization target for this active charge exchange technique. Because the cloud neutralization efficiency is uncertain, the PCX diagnostic is not absolutely calibrated so only relative density profiles are obtained. A mass and energy resolving E∥B neutral particle analyzer (NPA) is used which has eight energy channels covering the energy range of 0.3-3.7 MeV for α particles with energy resolution ranging from 5.8% to 11.3% and a spatial resolution of ˜5 cm. The PCX diagnostic views deeply trapped ions in a narrow pitch angle range around a mean value of v∥/v=-0.048±10-3. For D-T operation, the NPA was shielded by a polyethylene-lead enclosure providing 100× attenuation of ambient γ radiation and 14 MeV neutrons. The PCX diagnostic technique and its application on TFTR are described in detail.

  7. On the Ablation Models of Fuel Pellets

    SciTech Connect

    Rozhansky, V.A.; Senichenkov, I.Yu.

    2005-12-15

    The neutral gas shielding model and neutral-gas-plasma shielding model are analyzed qualitatively. The main physical processes that govern the formation of the shielding gas cloud and, consequently, the ablation rate are considered. For the neutral gas shielding model, simple formulas relating the ablation rate and cloud parameters to the parameters of the pellet and the background plasma are presented. The estimates of the efficiency of neutral gas shielding and plasma shielding are compared. It is shown that the main portion of the energy flux of the background electrons is released in the plasma cloud. Formulas for the ablation rate and plasma parameters are derived in the neutral-gas-plasma shielding model. The question is discussed as to why the neutral gas shielding model describes well the ablation rate of the pellet material, although it does not take into account the ionization effects and the effects associated with the interaction of ionized particles with the magnetic field. The reason is that the ablation rate depends weakly on the energy flux of hot electrons; as a result, the attenuation of this flux by the electrostatic shielding and plasma shielding has little effect on the ablation rate. This justifies the use of the neutral gas shielding model to estimate the ablation rate (to within a factor of about 2) over a wide range of parameters of the pellet and the background plasma.

  8. Fabrication of high exposure nuclear fuel pellets

    DOEpatents

    Frederickson, James R.

    1987-01-01

    A method is disclosed for making a fuel pellet for a nuclear reactor. A mixture is prepared of PuO.sub.2 and UO.sub.2 powders, where the mixture contains at least about 30% PuO.sub.2, and where at least about 12% of the Pu is the Pu.sup.240 isotope. To this mixture is added about 0.3 to about 5% of a binder having a melting point of at least about 250.degree. F. The mixture is pressed to form a slug and the slug is granulated. Up to about 4.7% of a lubricant having a melting point of at least about 330.degree. F. is added to the granulated slug. Both the binder and the lubricant are selected from a group consisting of polyvinyl carboxylate, polyvinyl alcohol, naturally occurring high molecular weight cellulosic polymers, chemically modified high molecular weight cellulosic polymers, and mixtures thereof. The mixture is pressed to form a pellet and the pellet is sintered.

  9. Robotic thermal battery pellet fabrication

    NASA Astrophysics Data System (ADS)

    Kimbler, D. L.; Townsend, A. S.; Walton, R. D.; Jones, C. W.

    1985-03-01

    Thermal battery manufacturing at the General Electric Neutron Devices Department (GEND) is a sequence of operations involving materials processing, component manufacture, and assembly. These operations, for the most part, were manually performed although some operation were computer or fixture assisted. The high labor intensity and the need for process consistency in these operations made the conversion to a robotic work cell appealing in that it could increase productivity while allowing the reassignment of highly trained workers to other duties. An Alpha robot (Microbot, Inc.) was coupled with a Hewlett-Packard HP-9816 microcomputer, and custom software was developed to control the thermal battery manufacturing process. The software provided a menu driven main program with feedback at virtually every step to allow technicians with little or no computer experience to operate the system. Previously, one or two workers were assigned to each of several industrial presses used in the manufacture of thermal batteries. With the introduction of a robotic operator and a microcomputer process control, one worker alone could support two to three presses.

  10. Effects of intra-prelimbic prefrontal cortex injection of cannabidiol on anxiety-like behavior: involvement of 5HT1A receptors and previous stressful experience.

    PubMed

    Fogaça, M V; Reis, F M C V; Campos, A C; Guimarães, F S

    2014-03-01

    The prelimbic medial prefrontal cortex (PL) is an important encephalic structure involved in the expression of emotional states. In a previous study, intra-PL injection of cannabidiol (CBD), a major non-psychotomimetic cannabinoid present in the Cannabis sativa plant, reduced the expression of fear conditioning response. Although its mechanism remains unclear, CBD can facilitate 5HT1A receptor-mediated neurotransmission when injected into several brain structures. This study was aimed at verifying if intra-PL CBD could also induce anxiolytic-like effect in a conceptually distinct animal model, the elevated plus maze (EPM). We also verified if CBD effects in the EPM and contextual fear conditioning test (CFC) depend on 5HT1A receptors and previous stressful experience. CBD induced opposite effects in the CFC and EPM, being anxiolytic and anxiogenic, respectively. Both responses were prevented by WAY100,635, a 5HT1A receptor antagonist. In animals that had been previously (24h) submitted to a stressful event (2h-restraint) CBD caused an anxiolytic, rather than anxiogenic, effect in the EPM. This anxiolytic response was abolished by previous injection of metyrapone, a glucocorticoid synthesis blocker. Moreover, restraint stress increased 5HT1A receptors expression in the dorsal raphe nucleus, an effect that was attenuated by injection of metyrapone before the restraint procedure. Taken together, these results suggest that CBD modulation of anxiety in the PL depend on 5HT1A-mediated neurotransmission and previous stressful experience.

  11. Effects of pellet characteristics on L-lactic acid fermentation by R. oryzae: pellet morphology, diameter, density, and interior structure.

    PubMed

    Fu, Yong-Qian; Yin, Long-Fei; Zhu, Hua-Yue; Jiang, Ru; Li, Shuang; Xu, Qing

    2014-11-01

    The effects of pellet morphology, diameter, density, and interior structure on L-lactic acid fermentation by Rhizopus oryzae were characterized for different inoculum sizes and concentrations of peptone and CaCO3. Inoculum size was the most important factor determining pellet formation and diameter. The diameter decreased with increasing inoculum size, and larger pellets were observed for lower inoculum sizes. Peptone concentration had the greatest effect on pellet density, which increased with increasing peptone concentration. L-lactic acid production depended heavily on pellet density but not on pellet diameter. Low-density pellets formed easily under conditions of low peptone concentration and often had a relatively hollow structure, with a thin condensed layer surrounding the pellet and an extraordinarily loose biomass or hollow center. As expected, this structure greatly decreased production. The production of L-lactic acid increased until the density reached a certain level (50-60 kg/m(3)), in which the compact part was distributed homogeneously in the thick outer layer of the pellet and loose in the central layer. Homogeneously structured, denser pellets had limited mass transfer, causing a lower overall turnover rate. However, the interior structure remained nearly constant throughout all fermentation phases for pellets with the same density. CaCO3 concentration only had a slight influence on pellet diameter and density, probably because it increases spore germination and filamentous hypha extension. This work also provides a new analysis method to quantify the interior structure of pellets, thus giving insight into pellet structure and its relationship with productivity.

  12. Progress in modeling long glass and carbon fiber breakage during injection molding

    NASA Astrophysics Data System (ADS)

    Chen, Hongyu; Cieslinski, Mark; Baird, Donald G.

    2015-05-01

    This work is concerned with the modeling of in-machine fiber breakage during injection molding. A lab-scale single screw extruder is used to evaluate fiber breakage in the screw. Our experiments show that as the initial glass fiber pellets length is reduced relative to the channel width, the overall percent of breakage is reduced. We believe that the ratio of initial pellet length to the screw channel width, or diameter, is an important parameter determining the percent of fiber breakage. Data have been fit using an exponential decay model with a kinetic decay constant and a critical length value. This empirical model has been tested on an injection molding machine with a screw 1.6 times larger than that of our single screw extruder. The predicted average fiber length leaving the nozzle shows reasonable agreement with the measured value. For the injection molded end-gated-plaque produced by the same machine, additional fiber breakage has been observed in the runner. A hydrodynamic force based breakage model is combined with mold filling simulation to simulate the fiber breakage in the runner. For carbon fibers, similar breakage trends were observed in the single screw extruder indicating the applicability of our empirical model to carbon fiber.

  13. Isolation and identification of Clostridium spp. from infections associated with the injection of drugs: experiences of a microbiological investigation team.

    PubMed

    Brazier, J S; Duerden, B I; Hall, V; Salmon, J E; Hood, J; Brett, M M; McLauchlin, J; George, R C

    2002-11-01

    Pathogenic species of the genus Clostridium may contaminate the materials used in the injection of drugs and under the right conditions may cause serious or life-threatening disease. C. novyi type A was implicated in an outbreak of severe infection with high mortality in injecting drug users who injected heroin extravascularly. The isolation of such highly oxygen-sensitive clostridia from clinical material may require adherence to enhanced methods and, once isolated, commercially available anaerobe identification kits alone may not give an accurate identification. Additional phenotypic tests that are useful in recognising the main pathogenic species are described. Differentiation of C. novyi type A from C. botulinum type C in reference laboratories was based on 16S rDNA sequence data and specific neutralisation of cytopathic effects in tissue culture.

  14. Influences on particle shape in underwater pelletizing processes

    SciTech Connect

    Kast, O. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Musialek, M. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Geiger, K. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C. E-mail: matthias.musialek@ikt.uni-stuttgart.de E-mail: christian.bonten@ikt.uni-stuttgart.de

    2014-05-15

    Underwater pelletizing has gained high importance within the last years among the different pelletizing technologies, due to its advantages in terms of throughput, automation, pellet quality and applicability to a large variety of thermoplastics. The resulting shape and quality of pellets, however, differ widely, depending on material characteristics and effects not fully understood yet. In an experimental set-up, pellets of different volumes and shapes were produced and the medium pellet mass, the pellet surface and the bulk density were analyzed in order to identify the influence of material properties and process parameters. Additionally, the shaping kinetics at the die opening were watched with a specially developed camera system. It was found that rheological material properties correlate with process parameters and resulting particle form in a complex way. Higher cutting speeds were shown to have a deforming influence on the pellets, leading to less spherical s and lower bulk densities. More viscous materials, however, showed a better resistance against this. Generally, the viscous properties of polypropylene proofed to be dominant over the elastic ones in regard to their influence on pellet shape. It was also shown that the shapes filmed at the die opening and the actual form of the pellets after a cooling track do not always correlate, indicating a significant influence of thermodynamic properties during the cooling.

  15. Novel-shaped catalyst pellets for packed-bed reactors

    SciTech Connect

    Punuru, A.R.

    1987-01-01

    The effect of the shape of a catalyst pellet, on the performance of a packed bed reactor, is determined by evaluating the effectiveness factor and dimensionless overall rates of the catalyst pellet. Depending upon the values of Thiele modulus and Prater number the use of Novel-shaped catalyst pellets, such as Lessing ring type pellets or partition ring type pellets or spoked wheel type pellets, which improve the overall rate of the pellet, were suggested. The novel-shaped pellets were sectioned into a hollow cylinder and slabs. The dimensionless rates and effectiveness factors were determined for hollow cylinders and slabs separately and the total dimensionless overall rate for the pellet is obtained by adding, the individual rates for slabs and hollow cylinder. The catalyst shape effects were studied on the steam-methane reformer. It was found that using traditional catalyst, a hollow cylindrical pellet with R/sub i//R/sub p/ ratio of 0.39, the dimensionless overall rate decreased from 0.75 at the top, to 0.27 at the bottom of the reformer. Upon using Lessing rings at the top, partition rings at the center, and spoked wheel pellets at the bottom of the reformer, the reaction rate can be improved to 0.9 at the top and to 0.73 at the bottom of the reformer. Though benzene-hydrogenation is exothermic reaction, use of solid cylindrical pellet was suggested, because of the low Thiele modulus. Two-dimensional pseudo homogeneous and heterogeneous reactor models were solved for a first order nonisothermal reaction, considering isothermal pellets. The inclusion of nonisothermal effectiveness factor that consider shape effects was left for future work.

  16. Cabazitaxel Injection

    MedlinePlus

    ... injection is used along with prednisone to treat prostate cancer (cancer of a male reproductive organ) that has ... cabazitaxel injection is usually used in men with prostate cancer. If used by pregnant women, cabazitaxel injection can ...

  17. Fondaparinux Injection

    MedlinePlus

    ... fondaparinux injection.Talk to your doctor about the risk of using fondaparinux injection. ... Fondaparinux injection is used to prevent deep vein thrombosis (DVT; a blood ... Xa inhibitors. It works by decreasing the clotting ability of the blood.

  18. Morphine Injection

    MedlinePlus

    Morphine injection is used to relieve moderate to severe pain. Morphine is in a class of medications called opiate ( ... Morphine injection comes as a solution (liquid) to inject intramuscularly (into a muscle) or intravenously (into a ...

  19. Dexamethasone Injection

    MedlinePlus

    Dexamethasone injection is used to treat severe allergic reactions. It is used in the management of certain types of ... gastrointestinal disease, and certain types of arthritis. Dexamethasone injection is also used for diagnostic testing. Dexamethasone injection ...

  20. Romidepsin Injection

    MedlinePlus

    Romidepsin injection is used to treat cutaneous T-cell lymphoma (CTCL; a group of cancers of the immune system ... one other medication given by mouth or by injection. Romidepsin injection is in a class of medications ...

  1. Ondansetron Injection

    MedlinePlus

    Zofran® Injection ... Ondansetron injection is used to prevent nausea and vomiting caused by cancer chemotherapy and surgery. Ondansetron is in a ... medications: or any of the ingredients in ondansetron injection. Ask your pharmacist for a list of the ...

  2. Dynamic investigation of nutrient consumption and injection strategy in microbial enhanced oil recovery (MEOR) by means of large-scale experiments.

    PubMed

    Song, Zhiyong; Zhu, Weiyao; Sun, Gangzheng; Blanckaert, Koen

    2015-08-01

    Microbial enhanced oil recovery (MEOR) depends on the in situ microbial activity to release trapped oil in reservoirs. In practice, undesired consumption is a universal phenomenon but cannot be observed effectively in small-scale physical simulations due to the scale effect. The present paper investigates the dynamics of oil recovery, biomass and nutrient consumption in a series of flooding experiments in a dedicated large-scale sand-pack column. First, control experiments of nutrient transportation with and without microbial consumption were conducted, which characterized the nutrient loss during transportation. Then, a standard microbial flooding experiment was performed recovering additional oil (4.9 % Original Oil in Place, OOIP), during which microbial activity mostly occurred upstream, where oil saturation declined earlier and steeper than downstream in the column. Subsequently, more oil remained downstream due to nutrient shortage. Finally, further research was conducted to enhance the ultimate recovery by optimizing the injection strategy. An extra 3.5 % OOIP was recovered when the nutrients were injected in the middle of the column, and another additional 11.9 % OOIP were recovered by altering the timing of nutrient injection.

  3. Exploring Liquid Sequential Injection Chromatography to Teach Fundamentals of Separation Methods: A Very Fast Analytical Chemistry Experiment

    ERIC Educational Resources Information Center

    Penteado, Jose C.; Masini, Jorge Cesar

    2011-01-01

    Influence of the solvent strength determined by the addition of a mobile-phase organic modifier and pH on chromatographic separation of sorbic acid and vanillin has been investigated by the relatively new technique, liquid sequential injection chromatography (SIC). This technique uses reversed-phase monolithic stationary phase to execute fast…

  4. Colliding pulse injection experiments in non-collinear geometry for controlled laser plasma wakefield acceleration of electrons

    NASA Astrophysics Data System (ADS)

    Toth, Csaba; Nakamura, K.; Geddes, C.; Michel, P.; Schroeder, C.; Esarey, E.; Leemans, W.

    2006-10-01

    A method for controlled injection of electrons into a plasma wakefield relying on colliding laser pulses [1] has been proposed a decade ago to produce high quality relativistic electron beams with energy spread below 1% and normalized emittances < 1 micron from a laser wakefield accelerator (LWFA). The original idea uses three pulses in which one pulse excites the plasma wake and a trailing laser pulse collides with a counterpropagating one to form a beat pattern that boosts background electrons to catch the plasma wave. Another, two-beam off-axis injection method [2] with crossing angles varying from 180 to 90 degrees avoids having optical elements on the path of the electron beam and has been studied at the LOASIS facility of LBNL as a viable method for laser triggered injection. It allows low dark current operation with controllable final beam energy and low energy spread. Here, we report on progress of electron optical injection via the two-beam non-collinear colliding pulse scheme using multi-terawatt Ti:Sapphire laser beams (45 fs, 100s of mJ) focused onto a Hydrogen gas plume. Experimental results indicate that electron beam properties are affected by the second beam. *This work is supported by DoE under contract DE-AC02-05CH11231. [1] E. Esarey, et al, Phys. Rev. Lett 79, 2682 (1997) [2] G. Fubiani, Phys. Rev. E 70, 016402 (2004)

  5. Manufacture of Regularly Shaped Sol-Gel Pellets

    NASA Technical Reports Server (NTRS)

    Leventis, Nicholas; Johnston, James C.; Kinder, James D.

    2006-01-01

    An extrusion batch process for manufacturing regularly shaped sol-gel pellets has been devised as an improved alternative to a spray process that yields irregularly shaped pellets. The aspect ratio of regularly shaped pellets can be controlled more easily, while regularly shaped pellets pack more efficiently. In the extrusion process, a wet gel is pushed out of a mold and chopped repetitively into short, cylindrical pieces as it emerges from the mold. The pieces are collected and can be either (1) dried at ambient pressure to xerogel, (2) solvent exchanged and dried under ambient pressure to ambigels, or (3) supercritically dried to aerogel. Advantageously, the extruded pellets can be dropped directly in a cross-linking bath, where they develop a conformal polymer coating around the skeletal framework of the wet gel via reaction with the cross linker. These pellets can be dried to mechanically robust X-Aerogel.

  6. A curious pellet from a great horned owl (Bubo virginianus)

    USGS Publications Warehouse

    Woodman, N.; Dove, C.J.; Peurach, S.C.

    2005-01-01

    One of the traditional methods of determining the dietary preferences of owls relies upon the identification of bony remains of prey contained in regurgitated pellets. Discovery of a pellet containing a large, complete primary feather from an adult, male Ring-necked Pheasant (Phasianus colchicus) prompted us to examine in detail a small sample of pellets from a Great Horned Owl (Bubo virginianus). Our analyses of feather and hair remains in these pellets documented the presence of three species of birds and two species of mammals, whereas bones in the pellets represented only mammals. This finding indicates an important bias that challenges the reliability of owl pellet studies making use of only osteological remains.

  7. Modeling of MOX Fuel Pellet-Clad Interaction Using ABAQUS

    SciTech Connect

    Ambrosek, Richard G.; Pedersen, Robert C.; Maple, Amanda

    2002-07-01

    Post-irradiation examination (PIE) has indicated an increase in the outer diameter of fuel pins being irradiated in the Advanced Test Reactor (ATR) for the MOX irradiation program. The diameter increase is the largest in the region between fuel pellets. The fuel pellet was modeled using PATRAN and the model was evaluated using ABAQUS, version 6.2. The results from the analysis indicate the non-uniform clad diameter is caused by interaction between the fuel pellet and the clad. The results also demonstrate that the interaction is not uniform over the pellet axial length, with the largest interaction occurring in the region of the pellet-pellet interface. Results were obtained for an axisymmetric model and for a 1/8 pie shaped segment, using the coupled temperature-displacement solution technique. (authors)

  8. Microstructure of bentonite in iron ore green pellets.

    PubMed

    Bhuiyan, Iftekhar U; Mouzon, Johanne; Schröppel, Birgit; Kaech, Andres; Dobryden, Illia; Forsmo, Seija P E; Hedlund, Jonas

    2014-02-01

    Sodium-activated calcium bentonite is used as a binder in iron ore pellets and is known to increase strength of both wet and dry iron ore green pellets. In this article, the microstructure of bentonite in magnetite pellets is revealed for the first time using scanning electron microscopy. The microstructure of bentonite in wet and dry iron ore pellets, as well as in distilled water, was imaged by various imaging techniques (e.g., imaging at low voltage with monochromatic and decelerated beam or low loss backscattered electrons) and cryogenic methods (i.e., high pressure freezing and plunge freezing in liquid ethane). In wet iron ore green pellets, clay tactoids (stacks of parallel primary clay platelets) were very well dispersed and formed a voluminous network occupying the space available between mineral particles. When the pellet was dried, bentonite was drawn to the contact points between the particles and formed solid bridges, which impart strength to the solid compact.

  9. Effect of process variables on the density and durability of the pellets made from high moisture corn stover

    SciTech Connect

    Jaya Shankar Tumuluru

    2014-03-01

    A flat die pellet mill was used to understand the effect of high levels of feedstock moisture content in the range of 28–38% (w.b.), with die rotational speeds of 40–60 Hz, and preheating temperatures of 30–110 °C on the pelleting characteristics of 4.8 mm screen size ground corn stover using an 8 mm pellet die. The physical properties of the pelletised biomass studied are: (a) pellet moisture content, (b) unit, bulk and tapped density, and (c) durability. Pelletisation experiments were conducted based on central composite design. Analysis of variance (ANOVA) indicated that feedstock moisture content influenced all of the physical properties at P < 0.001. Pellet moisture content decreased with increase in preheating temperature to about 110 °C and decreasing the feedstock moisture content to about 28% (w.b.). Response surface models developed for quality attributes with respect to process variables has adequately described the process with coefficient of determination (R2) values of >0.88. The other pellet quality attributes such as unit, bulk, tapped density, were maximised at feedstock moisture content of 30–33% (w.b.), die speeds of >50 Hz and preheating temperature of >90 °C. In case of durability a medium moisture content of 33–34% (w.b.) and preheating temperatures of >70 °C and higher die speeds >50 Hz resulted in high durable pellets. It can be concluded from the present study that feedstock moisture content, followed by preheating, and die rotational speed are the interacting process variables influencing pellet moisture content, unit, bulk and tapped density and durability.

  10. Gemcitabine adsorbed onto carbon particles increases drug concentrations at the injection site and in the regional lymph nodes in an animal experiment and a clinical study.

    PubMed

    Guo, F; Mao, X; Wang, J; Luo, F; Wang, Z

    2011-01-01

    This study investigated whether gemcitabine, adsorbed onto activated carbon particles (GEM-AC), increased the concentration of gemcitabine at the injection site and in the regional lymph nodes in an experimental animal model and a clinical study. The adsorption isotherm for GEM-AC was defined, and the concentration and distribution of gemcitabine in rats (n = 50) and in patients with pancreatic cancer (n = 8) was investigated. Drug concentrations in plasma, tumour samples, lymph nodes and at the injection site were measured after GEM-AC or gemcitabine solution (GEM-Sol) were subcutaneously injected into the left hind foot pad in rats, or into pancreatic tumours in patients. These experiments showed that GEM-AC was selectively delivered to the regional lymph nodes and the injection site, from which it slowly released greater amounts of gemcitabine to maintain the free concentration of gemcitabine at a relatively high level for a long period of time. The administration of GEM-AC might enhance the anticancer effects of gemcitabine.

  11. Numerical investigation on lithium transport in the edge plasma of EAST real-time- Li-injection experiments in the frame of BOUT + +

    NASA Astrophysics Data System (ADS)

    Li, N. M.; Sun, J. Z.; Wang, Z. H.; Xu, X. Q.; Sun, Z.; Wang, L.; Hu, J. S.; Wang, D. Z.

    2016-10-01

    Experimental observations on applications of Lithium (Li) have indicated that Li could benefit plasma performance. But all these call for further investigation on lithium transport. A simple model has been developed by reducing Braginskii's equations with assumed quasi-neutral condition for transport of Li species in the edge plasma in the EAST experiments of real-time Li aerosol injection and implemented in the frame of BOUT + + . The simulation results show that Li atoms propagate inwards continuously during the Li injection, and the propagating depth of Li atoms depends on both the local plasma conditions along its path and the Li injection velocity. It is also found that Li ions accumulate rapidly in the edge, and only a small fraction of Li species can transport cross the magnetic field into the core. In the poloidal direction, Li ions drift swiftly downwards along the field lines, and transport much faster at the high field side than at the low field side. The strong interaction between background plasma and Li ions plays a critical role in determining the edge plasma profile. It is found that real-time Li injection raises the plasma density in the pedestal region and reduces the plasma temperature, just as has been observed experimentally National Magnetic Confinement Fusion Science Program of China No. 2013GB107003, National Natural Science Foundation of China No. 11575039.

  12. Durable zinc ferrite sorbent pellets for hot coal gas desulfurization

    DOEpatents

    Jha, Mahesh C.; Blandon, Antonio E.; Hepworth, Malcolm T.

    1988-01-01

    Durable, porous sulfur sorbents useful in removing hydrogen sulfide from hot coal gas are prepared by water pelletizing a mixture of fine zinc oxide and fine iron oxide with inorganic and organic binders and small amounts of activators such as sodium carbonate and molybdenite; the pellets are dried and then indurated at a high temperature, e.g., 1800.degree. C., for a time sufficient to produce crush-resistant pellets.

  13. Pellet acceleration using an ablation-controlled electrothermal launcher

    SciTech Connect

    Kincaid, R.W.; Bourham, M.A.; Gilligan, J.G.

    1995-12-31

    The NCSU ablation-controlled electrothermal launcher SIRENS has been used to accelerate plastic (Lexan polycarbonate) pellets to investigate the possibility of using electrothermal launchers as frozen pellet injectors for tokamak fueling. Successful installation of such a device would include a protective shell (sabot) to shield the hydrogenic pellet from ablation and allow it to maintain its integrity throughout the acceleration. The SIRENS device has been modified to include specially designed barrel sections equipped with diagnostic ports.

  14. Revealing accumulation zones of plastic pellets in sandy beaches.

    PubMed

    Moreira, Fabiana T; Balthazar-Silva, Danilo; Barbosa, Lucas; Turra, Alexander

    2016-11-01

    Microplastics such as pellets are reported worldwide on sandy beaches, and have possible direct and indirect impacts on the biota and physical characteristics of the habitats where they accumulate. Evaluations of their standing stock at different spatial scales generate data on levels of contamination. This information is needed to identify accumulation zones and the specific beach habitats and communities that are likely to be most affected. Standing stocks of plastic pellets were evaluated in 13 sandy beaches in São Paulo state, Brazil. The sampling strategy incorporated across-shore transects from coastal dunes and backshores, and vertical profiles of the accumulated pellets down to 1 m depth below the sediment surface. Accumulation zones were identified at regional (among beaches) and local (between compartments) scales. At the regional scale pellet density tended to increase at beaches on the central and southwestern coast, near ports and factories that produce and transport the largest amounts of pellets in the country. At the local scale coastal dunes showed larger accumulations of pellets than backshores. For both compartments pellets tended to occur deeper in areas where standing stocks were larger. Most of the pellets were concentrated from the surface down to 0.4 m depth, suggesting that organisms inhabiting this part of the sediment column are more exposed to the risks associated with the presence of pellets. Our findings shed light on the local and regional scales of spatial variability of microplastics and their consequences for assessment and monitoring schemes in coastal compartments.

  15. Pellet fueling development at Oak Ridge National Laboratory

    SciTech Connect

    Foster, C.A.; Milora, S.L.; Schuresko, D.D.; Combs, S.K.; Lunsford, R.V.

    1982-01-01

    A pellet injector development program has been under way at the Oak Ridge National Laboratory (ORNL) since 1976 with the goals of developing D/sub 2/, T/sub 2/ pellet fuel injectors capable of reliable repetitive fueling of reactors and of continued experimentation on contemporary plasma devices. The development has focused primarily on two types of injectors that show promise. One of these injectors is the centrifuge-type injector, which accelerates pellets in a high speed rotating track. The other is the gas or pneumatic gun, which accelerates pellets in a gun barrel using compressed helium of H/sub 2/ gas.

  16. Fecal pellets: role in sedimentation of pelagic diatoms.

    PubMed

    Schrader, H J

    1971-10-01

    Membrane-enclosed fecal pellets of planktonic herbivores were sampled at several depths in the Baltic Sea (459 meters deep) and off Portugal (4000 meters deep) by means of a Simonsen multinet. Pellets contained mainly empty shells of planktonic diatoms and silicoflagellates. Two kinds of fecal pellets were found, those with the remains of one species (for example, Thalassiosira baltica) and those with the remains of several species (for example, Chaetoceros, Achnanthes, and Thalassiosira). Siliceous skeletons were protected from dissolution during settling by a membrane around the pellet.

  17. Preparation of (U,Pu)O 2 pellets through sol-gel microsphere pelletization technique

    NASA Astrophysics Data System (ADS)

    Kumar, N.; Pai, Rajesh V.; Joshi, J. K.; Mukerjee, S. K.; Vaidya, V. N.; Venugopal, V.

    2006-12-01

    Mixed uranium-plutonium oxide microspheres were prepared by internal gelation process using feed solution of optimized composition. In the feed, total metal concentration was maintained at 1.5 M and hexamethylenetetramine (HMTA)-urea to metal mole ratio ( R) was kept at 1.0. The gel particles obtained from each batch were dried and heated at 250 °C in air and then calcined in O 2 at 800 °C followed by reduction in 8%H 2/92%N 2 at 600 °C for 1 h to obtain soft (U,Pu)O 2 microspheres containing 4 mol% Pu. The soft (U,Pu)O 2 microspheres were directly taken for the preparation of pellets. The microspheres were characterized with respect to surface area, tap density, crush strength and O/M ratio. X-ray diffraction analysis of the mixed oxide microspheres was carried out to identify the phases. The mixed oxide pellets were characterized for their density and micro-homogeneity. The sintering behaviour was studied by dilatometric investigations. The green pellets were sintered in 8%H 2/92%N 2 at 1600 °C for 2 h. The density of the sintered pellet was found to be 10.40 ± 0.05 g/cm 3 with grains in the size range of 3-6 μm with an excellent micro-homogeneity.

  18. Intratumor photosensitizer injection for photodynamic therapy: Pre-clinical experience with methylene blue, Pc 4, and Photofrin

    NASA Astrophysics Data System (ADS)

    Baran, Timothy M.; Foster, Thomas H.

    2016-03-01

    Intravenous administration of some photosensitizers, including the FDA-approved Photofrin, results in significant systemic photosensitivity and a 2-3-day drug-light interval. Direct intratumor injection of photosensitizer could potentially eliminate these negative aspects of photodynamic therapy (PDT), while requiring a lower photosensitizer dose to achieve comparable drug concentration in the target tissue. We performed PDT using intratumor injection of 3 photosensitizers, methylene blue (MB), Pc 4, and Photofrin, in mouse tumor models. After a 0-15 minute drug-light interval, illumination was delivered by appropriate diode lasers. For animals receiving MB or Pc 4, surface illumination was delivered using a microlens-terminated fiber. For animals receiving Photofrin, interstitial illumination was delivered by a 1 cm diffuser. In animals receiving MB or Pc 4, tumor dimensions were measured daily post-PDT, with a cure being defined as no palpable tumor 90 days post-treatment. For Photofrin, animals were sacrificed 24 hours post-PDT and tumors were excised, with samples HE stained to assess PDT-induced necrosis. 55% of tumors were cured with MB-PDT, and significant tumor growth delay (p=0.002) was observed for Pc 4. For Photofrin PDT, the mean necrosis radius was 3.4+/-0.8 mm, compared to 2.9+/-1.3 mm for systemic administration, which was not a significant difference (p=0.58). Intratumoral injection of the photosensitizers methylene blue, Pc 4, and Photofrin is feasible, and results in appreciable tumor response. Further investigation is necessary to optimize treatment protocols and assess the systemic photosensitivity induced by intratumor injection.

  19. Cell bricks-enriched platelet-rich plasma gel for injectable cartilage engineering - an in vivo experiment in nude mice.

    PubMed

    Zhu, Jun; Cai, Bolei; Ma, Qin; Chen, Fulin; Wu, Wei

    2013-10-01

    Clinical application of platelet-rich plasma (PRP)-based injectable tissue engineering is limited by weak mechanical properties and a rapid fibrinolytic rate. We proposed a new strategy, a cell bricks-stabilized PRP injectable system, to engineer and regenerate cartilage with stable morphology and structure in vivo. Chondrocytes from the auricular cartilage of rabbits were isolated and cultured to form cell bricks (fragmented cell sheet) or cell expansions. Fifteen nude mice were divided evenly (n = 5) into cells-PRP (C-P), cell bricks-PRP (CB-P) and cell bricks-cells-PRP (CB-C-P) groups. Cells, cell bricks or a cell bricks/cells mixture were suspended in PRP and were injected subcutaneously in animals. After 8 weeks, all the constructs were replaced by white resilient tissue; however, specimens from the CB-P and CB-C-P groups were well maintained in shape, while the C-P group appeared distorted, with a compressed outline. Histologically, all groups presented lacuna-like structures, glycosaminoglycan-enriched matrices and positive immunostaining of collagen type II. Different from the uniform structure presented in CB-C-P samples, CB-P presented interrupted, island-like chondrogenesis and contracted structure; fibrous interruption was shown in the C-P group. The highest percentage of matrix was presented in CB-C-P samples. Collagen and sGAG quantification confirmed that the CB-C-P constructs had statistically higher amounts than the C-P and CB-P groups; statistical differences were also found among the groups in terms of biomechanical properties and gene expression. We concluded that cell bricks-enriched PRP gel sufficiently enhanced the morphological stability of the constructs, maintained chondrocyte phenotypes and favoured chondrogenesis in vivo, which suggests that such an injectable, completely biological system is a suitable cell carrier for cell-based cartilage repair.

  20. Use of platelet-rich plasma in the care of sports injuries: our experience with ultrasound-guided injection

    PubMed Central

    Bernuzzi, Gino; Petraglia, Federica; Pedrini, Martina Francesca; De Filippo, Massimo; Pogliacomi, Francesco; Verdano, Michele Arcangelo; Costantino, Cosimo

    2014-01-01

    Background Platelet-rich plasma is being used more frequently to promote healing of muscle injuries. The growth factors contained in platelet-rich plasma accelerate physiological healing processes and the use of these factors is simple and minimally invasive. The aim of this study was to demonstrate the efficacy of ultrasound-guided injection of platelet-rich plasma in muscle strains and the absence of side effects. Materials and methods Fifty-three recreational athletes were enrolled in the study. The patients were recruited from the Emergency Room in the University Hospital at Parma according to a pre-defined protocol. Every patient was assessed by ultrasound imaging to evaluate the extent and degree of muscle injuries. Only grade II lesions were treated with three ultrasound-guided injections of autologous platelet-rich plasma every 7 days. Platelet concentrate was produced according to standard methods, with a 10% variability in platelet count. The platelet gel for clinical use was obtained by adding thrombin to the concentrates under standardised conditions. Outcomes assessed were: pain reduction, muscle function recovery and return to sports activity, ultrasound-imaging tissue healing, relapses, local infections, and any side effect during the treatment. Results In all cases muscle lesions healed fully on ultrasound-imaging, the pain disappeared, and muscle function recovery was documented with a return to sports activity. A single patient had a relapse 1 year after treatment. Discussion Platelet-rich plasma injected into the injury site is one of the most important factors rendering the treatment effective. To maximise its efficacy the preliminary ultrasound must be done accurately to localise the lesion and guide the needle into the corresponding lesion. According to the current results, which document full muscle recovery and no relapse except for one case, platelet-rich plasma ultrasound-guided injection represents a valid mini-invasive treatment for

  1. Experiences of patients undergoing repeated intravitreal anti-vascular endothelial growth factor injections for neovascular age-related macular degeneration.

    PubMed

    Boyle, Jessica; Vukicevic, Meri; Koklanis, Konstandina; Itsiopoulos, Catherine; Rees, Gwyneth

    2017-01-09

    Current therapy to slow disease progression in patients with neovascular age-related macular degeneration (AMD) entails regular intravitreal anti-vascular endothelial growth factor (VEGF) injections, often indefinitely. Little is known about the burden imposed on patients by this repetitive treatment schedule and how this can be best managed. The aim of this study was to explore the psychosocial impact of repeated intravitreal injections on patients with neovascular AMD. Forty patients (16 males, 24 females) with neovascular AMD undergoing anti-VEGF treatment were recruited using purposive sampling from a private ophthalmology practice and public hospital in Melbourne. Patients were surveyed using the Macular Disease Treatment Satisfaction Questionnaire (MacTSQ; Bradley, Health Psychology Research Unit, Surrey, England) and underwent semi-structured, one-on-one interviews. Interview topics were: treatment burden and satisfaction; tolerability; barriers to adherence; treatment motivation; and patient education. Interviews were audio recorded and thematic analysis performed using NVivo 10 (QSR International, Doncaster, Australia). Patients recognised the importance of treatment to preserve eyesight, yet experienced significant psychosocial and practical burden from the treatment schedule. Important issues included treatment-related anxiety, financial considerations and transport burden placed on relatives or carers. Many patients were restricted to sedentary activities post-injection owing to treatment side effects. Patients prioritised treatment, often sacrificing family, travel and social commitments owing to a fear of losing eyesight if treatment was not received. Whilst anti-VEGF injections represent the current mainstay of treatment for neovascular AMD, the ongoing treatment protocol imposes significant burden on patients. An understanding of the factors that contribute to the burden of treatment may help inform strategies to lessen its impact and assist

  2. Ibandronate Injection

    MedlinePlus

    Boniva® Injection ... Ibandronate injection is used to treat osteoporosis (a condition in which the bones become thin and weak and break ... Ibandronate injection comes as a solution (liquid) to be injected into a vein by a doctor or nurse in ...

  3. Leuprolide Injection

    MedlinePlus

    Leuprolide injection comes as a long-acting suspension (Lupron) that is injected intramuscularly (into a muscle) by a doctor or nurse in a medical ... Depot-4 month, Lupron Depot-6 Month). Leuprolide injection also comes as a long-acting suspension (Eligard) that is injected subcutaneously (just under ...

  4. U.S. Drug Use and Migration experiences of Mexican Female Sex Workers who are injection Drug Users

    PubMed Central

    Ojeda, Victoria D.; Burgos, José Luis; Rangel, María Gudelia; Lozada, Remedios; Vera, Alicia

    2013-01-01

    Objective To describe U.S.-based drug/sex behaviors and correlates of lifetime U.S. drug use by Mexican female sex workers who inject drugs (FSW-IDUs). Methods Between 2008–2010, 315 migrant FSW-IDUs residing in Tijuana and Ciudad Juarez, Mexico responded to questionnaires. Results Twenty-seven percent (n=85) of FSW-IDUs were U.S. migrants; of these, 46% (n=39) were deportees. One-half of U.S.-migrant FSW-IDUs consumed illicit drugs in the U.S., and two-thirds of these injected drugs in the U.S. Among U.S. injectors, over 75% ever received or shared used injection equipment. The majority (92%) of U.S.-migrant FSW-IDUs never obtained U.S. drug treatment services. HIV prevalence was 4% among U.S.-migrant and 5% among non-U.S. migrant FSW-IDUs; 100% of U.S.-migrant and 75% of non-U.S. migrant FSW-IDUs were unaware of their HIV status. Conclusions Binational coordination to improve access to substance use treatment and HIV testing services in Mexico and the U.S. among marginalized binational migrants may be critical to containing HIV transmission. PMID:23698687

  5. Simulation of injector dynamics during steady inductive helicity injection current drive in the HIT-SI experiment

    SciTech Connect

    Hansen, C.; Marklin, G.; Victor, B.; Akcay, C.; Jarboe, T.

    2015-04-15

    We present simulations of inductive helicity injection in the Helicity Injected Torus with Steady Inductive helicity injection (HIT-SI) device that treats the entire plasma volume in a single dynamic MHD model. A new fully 3D numerical tool, the PSI-center TETrahedral mesh code, was developed that provides the geometric flexibility required for this investigation. Implementation of a zero-β Hall MHD model using PSI-TET will be presented including formulation of a new self-consistent magnetic boundary condition for the wall of the HIT-SI device. Results from simulations of HIT-SI are presented focusing on injector dynamics that are investigated numerically for the first time. Asymmetries in the plasma loading between the two helicity injectors and progression of field reversal in each injector are observed. Analysis indicates cross-coupling between injectors through confinement volume structures. Injector impedance is found to scale with toroidal current at fixed density, consistent with experimental observation. Comparison to experimental data with an injector drive frequency of 14.5 kHz shows good agreement with magnetic diagnostics. Global mode structures from Bi-Orthogonal decomposition agree well with experimental data for the first four modes.

  6. Applications and Progress of Dust Injection to Fusion Energy

    SciTech Connect

    Wang Zhehui; Wurden, Glen A.; Mansfield, Dennis K.; Roquemore, Lane A.; Ticos, Catalin M.

    2008-09-07

    Three regimes of dust injection are proposed for different applications to fusion energy. In the 'low-speed' regime (<5 km/s), basic dust transport study, edge plasma diagnostics, edge-localized-mode (ELM) pacing in magnetic fusion devices can be realized by injecting dust of known properties into today's fusion experiments. ELM pacing, as an alternative to mini-pellet injection, is a promising scheme to prevent disruptions and type I ELM's that can cause catastrophic damage to fusion devices. Different schemes are available to inject dust. In the 'intermediate-speed' regime (10-200 km/s), possible applications of dust injection include fueling of the next-step fusion devices, core-diagnostics of the next-step fusion devices, and compression of plasma and solid targets to aid fusion energy production. Promising laboratory results of dust moving at 10-50 km/s do exist. Significant advance in this regime may be expected in the near term to achieve higher dust speeds. In the 'high-speed' regime (>500 km/s), dust injection can potentially be used to directly produce fusion energy through impact. Ideas on how to achieve these extremely high speeds are mostly on paper. No plan exists today to realize them in laboratory. Some experimental results, including electrostatic, electromagnetic, gas-dragged, plasma-dragged, and laser-ablation-based acceleration, are summarized and compared. Some features and limitations of the different acceleration methods will be discussed. A necessary component of all dust injectors is the dust dropper (also known as dust dispenser). A computer-controlled piezoelectric crystals has been developed to dropped dust in a systematic and reproducible manner. Particle fluxes ranges from a few tens of particles per second up to thousands of particles per second by this simple device.

  7. The influence of polymeric subcoats and pellet formulation on the release of chlorpheniramine maleate from enteric coated pellets.

    PubMed

    Bruce, L Diane; Koleng, John J; McGinity, James W

    2003-09-01

    The influences of aqueous polymeric subcoats and pellet composition on the release properties of a highly water-soluble drug, chlorpheniramine maleate (CPM), from enteric coated pellets were investigated. Three different aqueous polymeric subcoats, Eudragit RD 100, Eudragit RS 30D, and Opadry AMB, were applied to 10% w/w CPM-loaded pellets that were then enteric coated with Eudragit L 30D-55. Observed drug release from the coated pellets in acidic media correlated with water vapor transmission rates derived for the subcoat films. The influence of pellet composition on retarding the release of CPM from enteric coated pellets in 0.1 N HCl was investigated. The rate of drug release was greatest for pellets prepared with lactose, microcrystalline cellulose, or dibasic calcium phosphate compared with pellets formulated with citric acid and microcrystalline cellulose. Citric acid reduced the pellet micro-environmental pH, decreasing the amount of drug leakage in 0.1 N HCL during the first 2 hr of dissolution. Polymer flocculation was observed when CPM was added to the Eudragit L 30D-55 dispersion. An adsorption isotherm was generated for mixtures of CPM and the polymer and the data were found to fit the Freundlich model for adsorption. Adsorption of CPM to the polymer decreased with the addition of citric acid to the drug-polymer mixtures.

  8. [Stability of liensinine injection].

    PubMed

    Hu, X M; Zhou, B H; Luo, S D

    1993-06-01

    The stability of liensinine injection was studied by accelarating test with classical isothermal method. Results of the study showed that the decomposition of the injection was found to be a first-order reaction. The activation energy was 75030 J.mol-1. The shelf life at 10 degrees C and 25 degrees C was predicted to be about 15 months and 3 months respectively. This experiment provides a reference for the storage of the injection.

  9. High-throughput automated dissolution method applicable for a wide dose range of controlled release pellets.

    PubMed

    Petruševska, Marija; Horvat, Matej; Peternel, Luka; Kristan, Katja

    2016-01-01

    The aim of the present study was to demonstrate the application of an automated high-throughput (HT) dissolution method as a useful screening tool for characterization of controlled release pellets in the formulation development phase. Five controlled release pellet formulations with drug substances exhibiting high or low solubility were chosen to investigate the correlation of the automated HT dissolution method with the conventional dissolution testing. Overall, excellent correlations (R(2 )>( )0.96) between the HT and the conventional dissolution method were obtained. In one case the initial unsatisfactory correlation (R(2 )=( )0.84) and poor method agreement (SD = 12.5) was improved by optimizing the HT dissolution method with design of experiment approach. Here in comparison to initial experimental HT dissolution settings, increased amount of pellets (25% of the capsule filling mass), lower temperature (22 °C) and no shaking resulted in significantly better correlation (R(2 )=( )0.97) and method agreement (SD = 5.3). These results show that such optimization is valuable for the development of HT dissolution methods. In conclusion, the high correlation of dissolution profiles obtained from the conventional and the automated HT dissolution method combined with low within-sample and measurement system variability, justifies the utilization of the automated HT dissolution method during development phase of controlled release pellets.

  10. Development of rapidly dissolving pellets within the Quality by Design approach.

    PubMed

    Karatzas, A A; Politis, S N; Rekkas, D M

    2017-05-01

    The purpose of this study was the development of novel, fast disintegrating, effervescent pellets by employing the direct pelletization technique as a single step process. In line with the Quality by Design (QbD) regulatory framework, statistical experimental design was extensively applied to correlate significant formulation and process variables with the critical quality attributes of the product. Pellets were studied with regards to sphericity, size and size distribution. In contrast to the existing multiparticulate platforms, this development integrated only water-soluble excipients to facilitate the multifunctional use of the final dosage form. The application of a screening fractional factorial design augmented to a full factorial design set the roadmap for the rational selection of the composition and process parameters, revealing in parallel the positive contribution of the powder feeder on the CQAs, when the critical process and formulation factors were properly adjusted. The response surface methodology was exploited for the final process optimization phase, which allowed the construction of appropriate mathematical models connecting the input variables and the CQAs under study. The implementation of the desirability function, lead to the optimum formulation and process settings for the production of pellets with narrow size distribution and geometric mean diameter of approximately 800 μm. In conclusion, using a lean approach supported by design of experiments (DoE) techniques within the QbD framework, a novel multifunctional formulation platform has been developed.

  11. Effect of Experimental Conditions on Cementite Formation During Reduction of Iron Ore Pellets

    NASA Astrophysics Data System (ADS)

    Kazemi, Mania; Sichen, Du

    2016-12-01

    Experiments have been carried out to study the effect of temperature, gas composition, residence time, and type of iron ore pellets on formation of cementite during gaseous reduction of hematite. Industrial iron ore pellets have been reduced isothermally in a gas mixture with H2 and CO as main components. The presence of Fe3C in the partially reduced pellets shows that reduction and cementite formation take place at the same time. The maximum content of cementite is identified in the samples reduced by H2-CO at 1123 K (850 °C). The decrease in the carbide content due to addition of 1 pct CO2 to the initial gas mixture reveals the major influence of carbon potential in the gas atmosphere. Further increase of CO2 content increases the Fe3C. The variations of the amount of cementite with the CO2 content suggest that both the thermodynamics and kinetics of cementite formation are affected by the gas composition. Cementite decomposes to graphite and iron particles in reducing and inert atmospheres as the residence time of pellets at high temperature is increased above 60 minutes.

  12. Ceria-thoria pellet manufacturing in preparation for plutonia-thoria LWR fuel production

    NASA Astrophysics Data System (ADS)

    Drera, Saleem S.; Björk, Klara Insulander; Sobieska, Matylda

    2016-10-01

    Thorium dioxide (thoria) has potential to assist in niche roles as fuel for light water reactors (LWRs). One such application for thoria is its use as the fertile component to burn plutonium in a mixed oxide fuel (MOX). Thor Energy and an international consortium are currently irradiating plutonia-thoria (Th-MOX) fuel in an effort to produce data for its licensing basis. During fuel-manufacturing research and development (R&D), surrogate materials were utilized to highlight procedures and build experience. Cerium dioxide (ceria) provides a good surrogate platform to replicate the chemical nature of plutonium dioxide. The project's fuel manufacturing R&D focused on powder metallurgical techniques to ensure manufacturability with the current commercial MOX fuel production infrastructure. The following paper highlights basics of the ceria-thoria fuel production including powder milling, pellet pressing and pellet sintering. Green pellets and sintered pellets were manufactured with average densities of 67.0% and 95.5% that of theoretical density respectively.

  13. Managing la malilla: Exploring drug treatment experiences among injection drug users in Tijuana, Mexico, and their implications for drug law reform

    PubMed Central

    Syvertsen, Jennifer; Pollini, Robin A.; Lozada, Remedios; Vera, Alicia; Rangel, Gudelia; Strathdee, Steffanie A.

    2012-01-01

    Background In August 2009, Mexico reformed its drug laws and decriminalized small quantities of drugs for personal use; offenders caught three times will be mandated to enter drug treatment. However, little is known about the quality or effectiveness of drug treatment programs in Mexico. We examined injection drug users’ (IDUs) experiences in drug treatment in Tijuana, Mexico, with the goal of informing program planning and policy. Methods We examined qualitative and quantitative data from Proyecto El Cuete, a multi-phased research study on HIV risk among IDUs in Tijuana. Phase I consisted of 20 in-depth interviews and Phase II employed respondent-driven sampling to recruit 222 IDUs for a quantitative survey. We also reviewed national drug policy documents, surveillance data, and media reports to situate drug users’ experiences within the broader sociopolitical context. Results Participants in the qualitative study were 50% male with a mean age of 32; most injected heroin (85.0%) and methamphetamine (60.0%). The quantitative sample was 91.4% male with a mean age of 35; 98.2% injected heroin and 83.7% injected heroin and methamphetamine together. The majority of participants reported receiving treatment: residential treatment was most common, followed by methadone; other types of services were infrequently reported. Participants’ perceptions of program acceptability and effectiveness were mixed. Mistreatment emerged as a theme in the qualitative interviews and was reported by 21.6% of Phase II participants, primarily physical (72.0%) and verbal (52.0%) abuse. Conclusions Our results point to the need for political, economic, and social investment in the drug treatment system before offenders are sentenced to treatment under the revised national drug law. Resources are needed to strengthen program quality and ensure accountability. The public health impact of the new legislation that attempts to bring drug treatment to the forefront of national drug policy

  14. Ionization recombination processes and ablation cloud structure for a carbon pellet

    NASA Astrophysics Data System (ADS)

    Morozov, D. Kh.; Gervids, V. I.; Senichenkov, I. Yu.; Veselova, I. Yu.; Rozhansky, V. A.; Schneider, R.

    2004-02-01

    Modelling of carbon pellet injection into hot hydrogen plasma is performed. Models of ionization and radiation processes previously used for descriptions of the ablation clouds are discussed. It is demonstrated that the assumption made by other authors that the plasma is transparent significantly overestimated ionization lengths for carbon. The optical thickness of the cloud is estimated. With typical ablation rates, the cloud in the vicinity of the pellet is opaque for resonant radiation in lines, in contrast to the visual transparency for non-resonant photons. The ionization by incident electrons is not sufficient to provide the short experimental cloud sizes. A reduced model for the ion stripping dynamics and energy losses in optically thick plasmas is proposed. Two very important phenomena are taken into account: partial trapping of resonant photons in the cloud and ionization from the excited state. The model is included into the MHD pellet code LLP. Calculations with the new model show at least a qualitative agreement with the experimental sizes of the carbon clouds, in contrast to the models used earlier.

  15. Experiment on synchronization of semiconductor lasers by common injection of constant-amplitude random-phase light.

    PubMed

    Aida, Hiroki; Arahata, Masaya; Okumura, Haruka; Koizumi, Hayato; Uchida, Atsushi; Yoshimura, Kazuyuki; Muramatsu, Jun; Davis, Peter

    2012-05-21

    We experimentally and numerically observe the synchronization between two semiconductor lasers induced by common optical injection with constant-amplitude and random-phase modulation in configurations with and without optical feedback. Large cross correlation (~0.9) between the intensity oscillations of the two response lasers can be achieved although the correlation between the drive laser and either one of the two response lasers is very small (~0.2). High quality synchronization is achieved in the presence of optical feedback in response lasers with matched feedback phase offset. We investigate the dependence of synchronization on parameter values over wide parameter ranges.

  16. Oxidizing Roasting Performances of Coke Fines Bearing Brazilian Specularite Pellets

    NASA Astrophysics Data System (ADS)

    Chun, Tiejun; Zhu, Deqing

    2016-06-01

    Oxidized pellets, consisting of Brazilian specularite fines and coke fines, were prepared by disc pelletizer using bentonite as binder. The roasting process of pellets includes preheating stage and firing stage. The compressive strength of preheated pellets and fired pellets reached the peak value at 1.5% coke fines dosage. During the initial stage of preheating, some original Fe2O3 was reduced to Fe3O4 because of partial reduction atmosphere in pellet. During the later stage of preheating and firing stage, coke fines were burnt out, and the secondary Fe2O3 (new generation Fe2O3) was generated due to the re-oxidization of Fe3O4, which improved the recrystallization of Fe2O3. Compared with the fired pellets without adding coke fines, fired pellets with 1.5% coke fines exhibited the comparable RSI (reduction swelling index) and RDI+3.15 mm (reduction degradation index), and slightly lower RI (reducibility index).

  17. Unique neuro-ophthalmic presentation of gun pellet injury.

    PubMed

    Sharma, Reena; Sharma, Sanjay; Phuljhele, Swati; Saxena, Rohit

    2016-01-01

    We describe a unique case of orbital gunshot injury with isolated intraorbital pellets lodged symmetrically in the two apices, causing identical clinical presentation, and absence of any associated globe or cerebral injury. He developed bilateral complete third nerve palsy with bilateral traumatic optic neuropathy. The optic nerve strut prevented the pellets from going into the brain on both the sides.

  18. Unique neuro-ophthalmic presentation of gun pellet injury

    PubMed Central

    Sharma, Reena; Sharma, Sanjay; Phuljhele, Swati; Saxena, Rohit

    2016-01-01

    We describe a unique case of orbital gunshot injury with isolated intraorbital pellets lodged symmetrically in the two apices, causing identical clinical presentation, and absence of any associated globe or cerebral injury. He developed bilateral complete third nerve palsy with bilateral traumatic optic neuropathy. The optic nerve strut prevented the pellets from going into the brain on both the sides. PMID:27843239

  19. 21 CFR 520.300b - Cambendazole pellets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Cambendazole pellets. 520.300b Section 520.300b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.300b Cambendazole pellets....

  20. Use of Candida antigen injections for the treatment of verruca vulgaris: A two-year mayo clinic experience.

    PubMed

    Alikhan, Ali; Griffin, John R; Newman, Catherine C

    2016-08-01

    Common warts (verruca vulgaris) are one of the most common problems encountered in dermatology and may present a difficult treatment dilemma, as no particular therapy has demonstrated complete efficacy. Intralesional injection of purified Candida antigen has produced impressive treatment results in small prospective and retrospective studies and is thought to produce its effect through stimulation of a cell-mediated immune response. We report a retrospective study of adult and pediatric patients treated with Candida antigen therapy in clinical practice. Of the 100 patients treated, 80% responded to therapy: 39% demonstrated a complete response and 41% demonstrated a partial response. In addition, 6 out of 7 immunocompromised patients who were treated demonstrated a partial or complete response. Injections were generally well-tolerated and adverse events were minimal and short-lived. Our data indicate that intralesional Candida antigen therapy for cutaneous warts is an efficacious option in a clinical practice setting. The treatment may also be effective in immunosuppressed patients with cutaneous warts. Our results add to the literature one of the largest retrospective series reported to date and treatment outcomes are similar to previously reported studies evaluating this therapeutic modality.

  1. Using Optical Oxygen Sensors and Injection Experiments to Determine in situ Microbial Rate Constants for Methane Oxidation and Heterotrophic Respiration in a Boreal Bog and Fen

    NASA Astrophysics Data System (ADS)

    Waldo, N.; Moorberg, C.; Waldrop, M. P.; Turetsky, M. R.; Neumann, R. B.

    2015-12-01

    Wetlands are the largest natural source of methane to the atmosphere, and play a key role in feedback cycles to climate change. In recognition of this, many researchers are developing process-based models of wetland methane emissions at various scales. In these models, the three key biogeochemical reactions are methane production, methane oxidation, and heterotrophic respiration, and they are modeled using Michaelis-Menten kinetics. The majority of Michaelis-Menten rate constants used in models are based on experiments involving slurries of peat incubated in vials. While these slurries provide a highly controlled setting, they are different from in situ conditions in multiple ways; notably they lack live plants and the centimeter-scale heterogeneities that exist in the field. To determine rate constants in a system more representative of in situ conditions, we extracted peat cores intact from a bog and fen located in the Bonanza Creek Experimental Forest near Fairbanks, Alaska and part of the Alaska Peatland Experiment (APEX) research program. Into those cores we injected water with varying concentrations of methane and oxygen at multiple depths. We used planar oxygen sensors installed on the peat cores to collect high resolution, two dimensional oxygen concentration data during the injections and used oxygen consumption rates under various conditions to calculate rate constants. Results were compared to a similar but smaller set of injection experiments conducted against planar oxygen sensors installed in the bog. Results will inform parametrization of microbial processes in wetland models, improving estimates of methane emissions both under current climate conditions and in the future.

  2. Practical experience applied to the design of injection and sample manifolds to perform in-place surveillance tests according to ANSI/ASME N-510

    SciTech Connect

    Banks, E.M.; Wikoff, W.O.; Shaffer, L.L.

    1997-08-01

    At the current level of maturity and experience in the nuclear industry, regarding testing of air treatment systems, it is now possible to design and qualify injection and sample manifolds for most applications. While the qualification of sample manifolds is still in its infancy, injection manifolds have reached a mature stage that helps to eliminate the {open_quotes}hit or miss{close_quotes} type of design. During the design phase, manifolds can be adjusted to compensate for poor airflow distribution, laminar flow conditions, and to take advantage of any system attributes. Experience has shown that knowing the system attributes before the design phase begins is an essential element to a successful manifold design. The use of a spreadsheet type program commonly found on most personal computers can afford a greater flexibility and a reduction in time spent in the design phase. The experience gained from several generations of manifold design has culminated in a set of general design guidelines. Use of these guidelines, along with a good understanding of the type of testing (theoretical and practical), can result in a good manifold design requiring little or no field modification. The requirements for manifolds came about because of the use of multiple banks of components and unconventional housing inlet configurations. Multiple banks of adsorbers and pre and post HEPA`s required that each bank be tested to insure that each one does not exceed a specific allowable leakage criterion. 5 refs., 5 figs., 1 tab.

  3. ["Piggyback" shot: ballistic parameters of two simultaneously discharged airgun pellets].

    PubMed

    Frank, Matthias; Schönekess, Holger C; Grossjohann, Rico; Ekkernkamp, Axel; Bockholdt, Britta

    2014-01-01

    Green and Good reported an uncommon case of homicide committed with an air rifle in 1982 (Am. J. Forensic Med. Pathol. 3: 361-365). The fatal wound was unusual in that two airgun pellets were loaded in so-called "piggyback" fashion into a single shot air rifle. Lack of further information on the ballistic characteristics of two airgun pellets as opposed to one conventionally loaded projectile led to this investigation. The mean kinetic energy (E) of the two pellets discharged in "piggyback" fashion was E = 3.6 J and E = 3.4 J, respectively. In comparison, average kinetic energy values of E = 12.5 J were calculated for conventionally discharged single diabolo pellets. Test shots into ballistic soap confirmed the findings of a single entrance wound as reported by Green and Good. While the ballistic background of pellets discharged in "piggyback" fashion could be clarified, the reason behind this mode of shooting remains unclear.

  4. Calculation of density profiles in tandem mirrors fueled by pellets

    SciTech Connect

    Campbell, R.B.; Gilmore, J.M.

    1983-12-02

    We have modified the LLNL radial transport code TMT to model reactor regime plasmas, fueled by pellets. The source profiles arising from pellet fueling are obtained from existing pellet ablation models. Because inward radial diffusion due to inverted profiles must compete with trapping of central cell ions in the transition region for tandem mirrors, pellets must penetrate fairly far into the plasma. In fact, based on our radial calculations, a pellet with a velocity of 10 km/sec cannot sustain the central flux tubes; a velocity more like 100 km/sec will be necessary. We also find that the central cell radial diffusion must exceed classical by about a factor of 100.

  5. Straw pellets as fuel in biomass combustion units

    SciTech Connect

    Andreasen, P.; Larsen, M.G.

    1996-12-31

    In order to estimate the suitability of straw pellets as fuel in small combustion units, the Danish Technological Institute accomplished a project including a number of combustion tests in the energy laboratory. The project was part of the effort to reduce the use of fuel oil. The aim of the project was primarily to test straw pellets in small combustion units, including the following: ash/slag conditions when burning straw pellets; emission conditions; other operational consequences; and necessary work performance when using straw pellets. Five types of straw and wood pellets made with different binders and antislag agents were tested as fuel in five different types of boilers in test firings at 50% and 100% nominal boiler output.

  6. Analysis of pellet properties with use of artificial neural networks.

    PubMed

    Mendyk, Aleksander; Kleinebudde, Peter; Thommes, Markus; Yoo, Angelina; Szlęk, Jakub; Jachowicz, Renata

    2010-11-20

    The objective was to prepare neural models identifying relationships between formulation characteristics and pellet properties based on algorithmic approach of crucial variables selection and neuro-fuzzy systems application. The database consisted of information about 227 pellet formulations prepared by extrusion/spheronization method, with various model drugs and excipients. Cheminformatic description of excipients and model drugs was employed for numerical description of pellet formulations. Initial numbers of neural model inputs were up to around 3000. The inputs reduction procedure based on sensitivity analysis allowed to obtain less than 40 inputs for each model. The reduced models were subjects of fuzzy logic implementation resulting in logical rules tables providing human-readable rule sets applicable in future development of pellet formulations. Neural modeling enhanced knowledge about pelletization process and provided means for future computer-guided search for the optimal formulation.

  7. Pelletizing/reslurrying as a means of distributing and firing clean coal

    SciTech Connect

    Not Available

    1992-06-09

    This volume contains appendices for: atomization test report; cost estimation model--pelletization material balance and equipment selection; cost estimation model--pelletization capital investment estimates; cost estimation--pelletization operating cost estimates; cost estimation model--pellet-CWF formulation material balance and equipment selection; cost estimation model--pellet-CWF capital investment estimates; cost estimation model--pellet-CWF operating cost estimates; and cost estimation model--direct CWF operating cost estimates.

  8. Solar drying of yam-flour pellets

    SciTech Connect

    Oladiran, M.T.

    1987-01-01

    An experimental investigation of the heat/mass transfer characteristics of a turbulent impinging jet in cross flow in a model of a chamber used for solar drying of yam flour pellets is presented. The variables studied were the nozzle inclination, ..cap alpha.. and the jet-to-cross flow velocity ratio, M. These parameters were varied from 30/sup 0/ to 135/sup 0/ and from 5.0 to 20.9 respectively. Superimposing a cross flow onto the jet reduced the heat transfer coefficients. At low cross flows, inclining the nozzle further reduced the heat transfer coefficients. However, at higher cross flows, inclining the nozzle could be beneficial. The thin film napthalene sublimation technique was employed for the mass transfer measurements.

  9. Golimumab Injection

    MedlinePlus

    ... body and causes pain, swelling, and damage) including: rheumatoid arthritis (condition in which the body attacks its own ... doctor.If golimumab injection is used to treat rheumatoid arthritis, it may also be injected intravenously (into a ...

  10. Adalimumab Injection

    MedlinePlus

    ... causes pain, swelling, and damage) including the following: rheumatoid arthritis (a condition in which the body attacks its ... If you are using adalimumab injection to treat rheumatoid arthritis, your doctor may tell you to inject the ...

  11. Aripiprazole Injection

    MedlinePlus

    ... aripiprazole injection and aripiprazole extended-release injection developed gambling problems or other intense urges or behaviors that ... even if you do not realize that your gambling or any other intense urges or unusual behaviors ...

  12. Teduglutide Injection

    MedlinePlus

    ... mix and inject it.Teduglutide comes as a kit containing vials of teduglutide powder for injection, prefilled syringes containing diluent (liquid to be mixed with teduglutide powder), needles to attach to the diluent syringe, dosing syringes ...

  13. Degarelix Injection

    MedlinePlus

    Degarelix injection is used to treat advanced prostate cancer (cancer that begins in the prostate [a male reproductive gland]). Degarelix injection is in a class of medications called gonadotropin-releasing hormone (GnRH) ...

  14. Cyclosporine Injection

    MedlinePlus

    ... injection is used with other medications to prevent transplant rejection (attack of the transplanted organ by the ... people who have received kidney, liver, and heart transplants. Cyclosporine injection should only be used to treat ...

  15. Colistimethate Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria. Colistimethate injection is in a class of medications called antibiotics. It works by killing bacteria.Antibiotics such as colistimethate injection will not work ...

  16. Chloramphenicol Injection

    MedlinePlus

    ... treat certain types of serious infections caused by bacteria when other antibiotics cannot be used. Chloramphenicol injection ... antibiotics. It works by stopping the growth of bacteria..Antibiotics such as chloramphenicol injection will not work ...

  17. Estrogen Injection

    MedlinePlus

    ... forms of estrogen injection are used to treat hot flushes (hot flashes; sudden strong feelings of heat and sweating) ... If you are using estrogen injection to treat hot flushes, your symptoms should improve within 1 to ...

  18. Medroxyprogesterone Injection

    MedlinePlus

    ... Medroxyprogesterone injection is a very effective method of birth control but does not prevent the spread of human ... you have been using a different method of birth control and are switching to medroxyprogesterone injection, your doctor ...

  19. Etanercept Injection

    MedlinePlus

    ... areas causing pain and joint damage), chronic plaque psoriasis (a skin disease in which red, scaly patches ... etanercept injection is used to treat chronic plaque psoriasis, it may be injected twice a week during ...

  20. Levoleucovorin Injection

    MedlinePlus

    Levoleucovorin injection is used to prevent harmful effects of methotrexate (Rheumatrex, Trexall) when methotrexate is used to to treat certain types of cancer. Levoleucovorin injection is also used to treat people ...

  1. Leucovorin Injection

    MedlinePlus

    Leucovorin injection is used to prevent harmful effects of methotrexate (Rheumatrex, Trexall; cancer chemotherapy medication) when methotrexate is used to to treat certain types of cancer. Leucovorin injection is used to ...

  2. Teniposide Injection

    MedlinePlus

    ... in men. You should not become pregnant or breast-feed while you are receiving teniposide injection. If you or your partner become pregnant while receiving teniposide injection, call your doctor. Teniposide may harm the fetus.

  3. Ipilimumab Injection

    MedlinePlus

    ... are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving ipilimumab injection, call your doctor. Ipilimumab injection may cause your baby to be born too early or to die before birth.

  4. Pralatrexate Injection

    MedlinePlus

    Pralatrexate injection is used to treat peripheral T-cell lymphoma (PTCL; a form of cancer that begins in a ... come back after treatment with other medications. Pralatrexate injection has not been shown to help people who ...

  5. Cyanocobalamin Injection

    MedlinePlus

    Cyanocobalamin injection is used to treat and prevent a lack of vitamin B12 that may be caused by any ... organs) and permanent damage to the nerves. Cyanocobalamin injection also may be given as a test to ...

  6. Paclitaxel Injection

    MedlinePlus

    Paclitaxel injection manufactured with human albumin is used to treat breast cancer that has not improved or that has come back after treatment with other medications. Paclitaxel injection manufactured with polyoxyethylated castor oil is used to ...

  7. Diphenhydramine Injection

    MedlinePlus

    Diphenhydramine injection is used to treat allergic reactions, especially for people who are unable to take diphenhydramine by mouth. ... is used also to treat motion sickness. Diphenhydramine injection is also used alone or along with other ...

  8. Peramivir Injection

    MedlinePlus

    Peramivir injection is used to treat some types of influenza infection ('flu') in people who have had symptoms of ... flu for no longer than 2 days. Peramivir injection is in a class of medications called neuraminidase ...

  9. Cefotetan Injection

    MedlinePlus

    Cefotetan injection is used to treat infections of the lungs, skin, bones, joints, stomach area, blood, female reproductive organs, and urinary tract. Cefotetan injection is also used before surgery to prevent infections. ...

  10. Mipomersen Injection

    MedlinePlus

    Mipomersen injection is used to decrease levels of cholesterol and other fatty substances in the blood in people who ... that removes LDL from the blood), but mipomersen injection should not be used along with this treatment. ...

  11. Romiplostim Injection

    MedlinePlus

    Romiplostim injection is used to increase the number of platelets (cells that help the blood to clot) in order ... low number of platelets in the blood). Romiplostim injection should only be used in people who cannot ...

  12. Hydrocortisone Injection

    MedlinePlus

    Hydrocortisone injection is used to treat symptoms of low corticosteroid levels (lack of certain substances that are usually produced ... also used to treat severe allergic reactions. Hydrocortisone injection is used in the management of multiple sclerosis ( ...

  13. Palivizumab Injection

    MedlinePlus

    Palivizumab injection is used to help prevent respiratory syncytial virus (RSV; common virus that can cause serious lung infections) ... or have certain heart or lung diseases. Palivizumab injection is not used to treat the symptoms of ...

  14. Naltrexone Injection

    MedlinePlus

    Naltrexone injection is used along with counseling and social support to help people who have stopped drinking large amounts of alcohol to avoid drinking again. Naltrexone injection is also used along with counseling and social ...

  15. Tesamorelin Injection

    MedlinePlus

    Tesamorelin injection is used to decrease the amount of extra fat in the stomach area in adults with human ... fat in certain areas of the body). Tesamorelin injection is not used to help with weight loss. ...

  16. Tigecycline Injection

    MedlinePlus

    Tigecycline injection used to treat certain serious infections including community acquired pneumonia (a lung infection that developed in a ... area between the chest and the waist). Tigecycline injection should not be used to treat pneumonia that ...

  17. Eculizumab Injection

    MedlinePlus

    Eculizumab injection is used to treat paroxysmal nocturnal hemoglobinuria (PNH: a type of anemia in which too many red ... oxygen to all parts of the body). Eculizumab injection is also used to treat atypical hemolytic uremic ...

  18. Pembrolizumab Injection

    MedlinePlus

    Pembrolizumab injection is used to treat melanoma (a type of skin cancer) that cannot be treated with surgery or ... spread to other parts of the body. Pembrolizumab injection is also used to treat a certain type ...

  19. Methylprednisolone Injection

    MedlinePlus

    ... allergic reactions. Methylprednisolone injection is used in the management of multiple sclerosis (a disease in which the ... laboratory test, tell your doctor and the laboratory personnel that you are using methylprednisolone injection.If you ...

  20. Obinutuzumab Injection

    MedlinePlus

    Obinutuzumab injection is used with chlorambucil (Leukeran) to treat chronic lymphocytic leukemia (CLL; a type of cancer of the white blood cells). Obinutuzumab injection is in a class of medications called ...

  1. Iron Dextran Injection

    MedlinePlus

    ... the area where the medication was injected brown skin discoloration numbness, burning, or tingling in the arms, hands, feet, or legs sweating changes in taste Some side effects can be serious. If you experience these symptoms ...

  2. Development of Impregnated Agglomerate Pelletization (IAP) process for fabrication of (Th,U)O 2 mixed oxide pellets

    NASA Astrophysics Data System (ADS)

    Khot, P. M.; Nehete, Y. G.; Fulzele, A. K.; Baghra, Chetan; Mishra, A. K.; Afzal, Mohd.; Panakkal, J. P.; Kamath, H. S.

    2012-01-01

    Impregnated Agglomerate Pelletization (IAP) technique has been developed at Advanced Fuel Fabrication Facility (AFFF), BARC, Tarapur, for manufacturing (Th, 233U)O 2 mixed oxide fuel pellets, which are remotely fabricated in hot cell or shielded glove box facilities to reduce man-rem problem associated with 232U daughter radionuclides. This technique is being investigated to fabricate the fuel for Indian Advanced Heavy Water Reactor (AHWR). In the IAP process, ThO 2 is converted to free flowing spheroids by powder extrusion route in an unshielded facility which are then coated with uranyl nitrate solution in a shielded facility. The dried coated agglomerate is finally compacted and then sintered in oxidizing/reducing atmosphere to obtain high density (Th,U)O 2 pellets. In this study, fabrication of (Th,U)O 2 mixed oxide pellets containing 3-5 wt.% UO 2 was carried out by IAP process. The pellets obtained were characterized using optical microscopy, XRD and alpha autoradiography. The results obtained were compared with the results for the pellets fabricated by other routes such as Coated Agglomerate Pelletization (CAP) and Powder Oxide Pelletization (POP) route.

  3. Comparison of film-coated retarded release pellets manufactured by layering technique or by bed rotor pelletization.

    PubMed

    Priese, Florian; Frisch, Toni; Wolf, Bertram

    2015-06-01

    In order to investigate the influence of coatings for controlled active pharmaceutical ingredient (API) release, two types of pellets were used. Microcrystalline pellets were coated with a model API using the Wurster fluidized bed technique in laboratory scale (layered Cellets). Another type of pellets consisting of microcrystalline cellulose and model API was manufactured by fluidized bed rotor pelletization (matrix pellets (MP)). Both kinds of pellets were coated in a Wurster fluidized bed process with a polymer mixture of ethylcellulose to achieve retarded API release. With layered Cellets and an increased thickness of the ethylcellulose layer, the lag-time was increased and the release rate was decreased. In the case of MP, retardation was less pronounced probable due to inhomogeneous polymer film formation as a result of the porous particle surface. To reduce the surface roughness, the MP were coated with polyvinylpyrrolidone (PVP) as an intermediate smoothing layer, in a first trial step by step. In a second trial, pelletization and the coating steps were performed in an uninterrupted process. Intermediate PVP coating improved the ethylcellulose film formation and led to a more pronounced retardation of API release. The uninterrupted process of matrix pellet manufacturing and coating results in a product with only low retarded release.

  4. Circular economy in drinking water treatment: reuse of ground pellets as seeding material in the pellet softening process.

    PubMed

    Schetters, M J A; van der Hoek, J P; Kramer, O J I; Kors, L J; Palmen, L J; Hofs, B; Koppers, H

    2015-01-01

    Calcium carbonate pellets are produced as a by-product in the pellet softening process. In the Netherlands, these pellets are applied as a raw material in several industrial and agricultural processes. The sand grain inside the pellet hinders the application in some high-potential market segments such as paper and glass. Substitution of the sand grain with a calcite grain (100% calcium carbonate) is in principle possible, and could significantly improve the pellet quality. In this study, the grinding and sieving of pellets, and the subsequent reuse as seeding material in pellet softening were tested with two pilot reactors in parallel. In one reactor, garnet sand was used as seeding material, in the other ground calcite. Garnet sand and ground calcite performed equally well. An economic comparison and a life-cycle assessment were made as well. The results show that the reuse of ground calcite as seeding material in pellet softening is technologically possible, reduces the operational costs by €38,000 (1%) and reduces the environmental impact by 5%. Therefore, at the drinking water facility, Weesperkarspel of Waternet, the transition from garnet sand to ground calcite will be made at full scale, based on this pilot plant research.

  5. Prevalence and Characteristics of Abuse Experiences and Depression Symptoms among Injection Drug-Using Female Sex Workers in Mexico

    PubMed Central

    Ulibarri, Monica D.; Hiller, Sarah P.; Lozada, Remedios; Rangel, M. Gudelia; Stockman, Jamila K.; Silverman, Jay G.; Ojeda, Victoria D.

    2013-01-01

    This mixed methods study examined the prevalence and characteristics of physical and sexual abuse and depression symptoms among 624 injection drug-using female sex workers (FSW-IDUs) in Tijuana and Ciudad Juarez, Mexico; a subset of 47 from Tijuana also underwent qualitative interviews. Linear regressions identified correlates of current depression symptoms. In the interviews, FSW-IDUs identified drug use as a method of coping with the trauma they experienced from abuse that occurred before and after age 18 and during the course of sex work. In a multivariate linear regression model, two factors—ever experiencing forced sex and forced sex in the context of sex work—were significantly associated with higher levels of depression symptoms. Our findings suggest the need for integrated mental health and drug abuse services for FSW-IDUs addressing history of trauma as well as for further research on violence revictimization in the context of sex work in Mexico. PMID:23737808

  6. U.S. Pellet Industry Analysis

    SciTech Connect

    Corrie I. Nichol; Jacob J. Jacobsen; Richard D. Boardman

    2011-06-01

    This report is a survey of the U.S. Pellet Industry, its current capacity, economic drivers, and projected demand for biomass pellets to meet future energy consumption needs. Energy consumption in the US is projected to require an ever increasing portion of renewable energy sources including biofuels, among which are wood, and agrictulrual biomass. Goals set by federal agencies will drive an ever increasing demand for biomass. The EIA projections estimate that renewable energy produced by 2035 will be roughly 10% of all US energy consumption. Further analysis of the biofuels consumption in the US shows that of the renewable energy sources excluding biofuels, nearly 30% are wood or biomass waste. This equates to roughly 2% of the total energy consumption in the US coming from biomass in 2009, and the projections for 2035 show a strong increase in this amount. As of 2009, biomass energy production equates to roughly 2-2.5 quadrillion Btu. The EIA projections also show coal as providing 21% of energy consumed. If biomass is blended at 20% to co-fire coal plants, this will result in an additional 4 quadrillion Btu of biomass consumption. The EISA goals aim to produce 16 billion gal/year of cellulosic biofuels, and the US military has set goals for biofuels production. The Air Force has proposed to replace 50% of its domestic fuel requirements with alternative fuels from renewable sources by 2016. The Navy has likewise set a goal to provide 50% of its energy requirements from alternative sources. The Department of Energy has set similarly ambitious goals. The DOE goal is to replace 40% of 2004 gasoline use with biofuels. This equates to roughly 60 billion gal/year, of which, 45 billion gal/year would be produced from lignocellulosic resources. This would require 530 million dry tons of herbaceous and woody lignocellulosic biomass per year.

  7. In vitro release of theophylline from poly(lactic acid) sustained-release pellets prepared by direct compression.

    PubMed

    Kader, A; Jalil, R

    1998-06-01

    Poly(L-lactic acid), (L-PLA) pellets containing theophylline as a model drug were prepared with increasing bovine serum albumin (BSA) load of 10, 20, 30, 40, or 50% by direct compression. The drug release from pellets was studied in phosphate buffered saline (PBS, pH 7.4) at 37 degrees C. The annealing effect on theophylline release from pellets was also studied at 20, 30, 60, and 80 degrees C. In all cases, release kinetics followed the Higuchian mechanism with an initial burst effect followed by sustained release of theophylline during the experimental period. Increasing BSA load resulted in a linear increase in Higuchian release rates presumably because of the hydrophilic nature of BSA. Furthermore, BSA did not interact chemically with the polymer matrix and was held physically by the dense polymer matrix. However, drug release decreased with an increase in annealing temperature. Release of theophylline was higher from PLA-BSA combination pellets compared to PLA pellets at temperatures below the glass transition temperature (Tg) of the polymer and lower for temperatures above Tg. The temperature effect on drug release may be attributed to both the reduction of core solubility in the bulk phase and the lowering of diffusibility of the polymeric membrane. No drug-polymer interactions or polymer degradation was observed within the experimental setup when studied by differential scanning calorimetry (DSC), infrared (FTIR) spectroscopy, and gravimetric methods. DSC studies of pellets showed no hints of microstructural changes (crystallinity) of the polymers. In our experiments, theophylline was released primarily by leaching through channels and not by polymer degradation. The release rate was dependent on BSA loading and annealing. It may be concluded that PLA pellets can be fabricated suitably using BSA and annealing to design sustained-release preparations of water-soluble drugs.

  8. Busulfan Injection

    MedlinePlus

    Busulfex® Injection ... Busulfan injection is used to treat a certain type of chronic myelogenous leukemia (CML; a type of cancer of ... of 16 doses) before bone marrow transplant.Busulfan injection may cause seizures during therapy with the medication. ...

  9. Effects of intra-infralimbic prefrontal cortex injections of cannabidiol in the modulation of emotional behaviors in rats: contribution of 5HT₁A receptors and stressful experiences.

    PubMed

    Marinho, A L Z; Vila-Verde, C; Fogaça, M V; Guimarães, F S

    2015-06-01

    The infralimbic (IL) and prelimbic (PL) regions of the prefrontal cortex are involved in behavioral responses observed during defensive reactions. Intra-PL or IL injections of cannabidiol (CBD), a major non-psychotomimetic cannabinoid present in the Cannabis sativa plant, result in opposite behavioral effects in the contextual fear conditioning (CFC) paradigm. The intra-PL effects of CBD are mediated by 5HT1A receptors and depend on previous stressful experiences but the mechanisms and effects of intra-IL CBD injected are unknown. To this aim the present work verified the effects of intra-IL administration of CBD on two animal models of anxiety, the elevated plus maze (EPM) and CFC. We also investigated if these effects were mediated by 5HT1A receptors and depended on previous stressful experience. Male Wistar rats received bilateral microinjections of vehicle, WAY100635 (5HT1A receptor antagonist, 0.37 nmol) and/or CBD (15, 30 or 60 nmol) before being submitted to the behavioral tests. Intra-IL CBD induced anxiolytic and anxiogenic in the EPM and CFC, respectively. To verify if these effects are influenced by the previous stressful experience (footshocks) in the CFC model, we tested the animals in the EPM 24h after a 2-h restraint period. The anxiolytic-like effect of CBD in the EPM disappeared when the animals were previously stressed. Both responses, i.e., anxiolytic and anxiogenic, were prevented by WAY100635, indicating that they involve local 5HT1A-mediated neurotransmission. Together these results indicate that CBD effects in the IL depend on the nature of the animal model, being influenced by previous stressful experiences and mediated by facilitation of 5HT1A receptors-mediated neurotransmission.

  10. Pellet formation of zygomycetes and immobilization of yeast.

    PubMed

    Nyman, Jonas; Lacintra, Michael G; Westman, Johan O; Berglin, Mattias; Lundin, Magnus; Lennartsson, Patrik R; Taherzadeh, Mohammad J

    2013-06-25

    Pelleted growth provides many advantages for filamentous fungi, including decreased broth viscosity, improved aeration, stirring, and heat transfer. Thus, the factors influencing the probability of pellet formation of Rhizopus sp. in a defined medium was investigated using a multifactorial experimental design. Temperature, agitation intensity, Ca(2+)-concentration, pH, and solid cellulose particles, each had a significant effect on pelletization. Tween 80, spore concentration, and liquid volume were not found to have a significant effect. All of the effects were additive; no interactions were significant. The results were used to create a simple defined medium inducing pelletization, which was used for immobilization of a flocculating strain of Saccharomyces cerevisiae in the zygomycetes pellets. A flor-forming S. cerevisiae strain was also immobilized, while a non-flocculating strain colonized the pellets but was not immobilized. No adverse effects were detected as a result of the close proximity between the filamentous fungus and the yeast, which potentially allows for co-fermentation with S. cerevisiae immobilized in pellets of zygomycetes.

  11. Pyrolysis of ground pine chip and ground pellet particles

    SciTech Connect

    Rezaei, Hamid; Yazdanpanah, Fahimeh; Lim, C. Jim; Lau, Anthony; Sokhansanj, Shahab

    2016-08-04

    In addition to particle size, biomass density influences heat and mass transfer rates during the thermal treatment processes. In this research, thermal behaviour of ground pine chip particles and ground pine pellet particles in the range of 0.25–5 mm was investigated. A single particle from ground pellets was almost 3 to 4 times denser than a single particle from ground chips at a similar size and volume of particle. Temperature was ramped up from room temperature (~25 °C) to 600 °C with heating rates of 10, 20, 30, and 50 °C/min. Pellet particles took 25–88 % longer time to dry than the chip particles. Microscopic examination of 3 mm and larger chip particles showed cracks during drying. No cracks were observed for pellet particles. The mass loss due to treatment at temperatures higher than 200 °C was about 80% both for chip and pellet particles. It took 4 min for chip and pellet particles to lose roughly 63% of their dry mass at a heating rate of 50 °C/min. The SEM structural analysis showed enlarged pores and cracks in cell walls of the pyrolyzed wood chips. As a result, these pores were not observed in pyrolyzed pellet particles.

  12. Pyrolysis of ground pine chip and ground pellet particles

    DOE PAGES

    Rezaei, Hamid; Yazdanpanah, Fahimeh; Lim, C. Jim; ...

    2016-08-04

    In addition to particle size, biomass density influences heat and mass transfer rates during the thermal treatment processes. In this research, thermal behaviour of ground pine chip particles and ground pine pellet particles in the range of 0.25–5 mm was investigated. A single particle from ground pellets was almost 3 to 4 times denser than a single particle from ground chips at a similar size and volume of particle. Temperature was ramped up from room temperature (~25 °C) to 600 °C with heating rates of 10, 20, 30, and 50 °C/min. Pellet particles took 25–88 % longer time to drymore » than the chip particles. Microscopic examination of 3 mm and larger chip particles showed cracks during drying. No cracks were observed for pellet particles. The mass loss due to treatment at temperatures higher than 200 °C was about 80% both for chip and pellet particles. It took 4 min for chip and pellet particles to lose roughly 63% of their dry mass at a heating rate of 50 °C/min. The SEM structural analysis showed enlarged pores and cracks in cell walls of the pyrolyzed wood chips. As a result, these pores were not observed in pyrolyzed pellet particles.« less

  13. Consolidated waste forms: glass marbles and ceramic pellets

    SciTech Connect

    Treat, R.L.; Rusin, J.M.

    1982-05-01

    Glass marbles and ceramic pellets have been developed at Pacific Northwest Laboratory as part of the multibarrier concept for immobilizing high-level radioactive waste. These consolidated waste forms served as substrates for the application of various inert coatings and as ideal-sized particles for encapsulation in protective matrices. Marble and pellet formulations were based on existing defense wastes at Savannah River Plant and proposed commercial wastes. To produce marbles, glass is poured from a melter in a continuous stream into a marble-making device. Marbles were produced at PNL on a vibratory marble machine at rates as high as 60 kg/h. Other marble-making concepts were also investigated. The marble process, including a lead-encapsulation step, was judged as one of the more feasible processes for immobilizing high-level wastes. To produce ceramic pellets, a series of processing steps are required, which include: spray calcining - to dry liquid wastes to a powder; disc pelletizing - to convert waste powders to spherical pellets; sintering - to densify pellets and cause desired crystal formation. These processing steps are quite complex, and thereby render the ceramic pellet process as one of the least feasible processes for immobilizing high-level wastes.

  14. Monitoring mass transport in heterogeneously catalyzed reactions by field-gradient NMR for assessing reaction efficiency in a single pellet

    NASA Astrophysics Data System (ADS)

    Buljubasich, L.; Blümich, B.; Stapf, S.

    2011-09-01

    An important aspect in assessing the performance of a catalytically active reactor is the accessibility of the reactive sites inside the individual pellets, and the mass transfer of reactants and products to and from these sites. Optimal design often requires a suitable combination of micro- and macropores in order to facilitate mass transport inside the pellet. In an exothermic reaction, fluid exchange between the pellet and the surrounding medium is enhanced by convection, and often by the occurrence of gas bubbles. Determining mass flow in the vicinity of a pellet thus represents a parameter for quantifying the reaction efficiency and its dependence on time or external reaction conditions. Field gradient Nuclear Magnetic Resonance (NMR) methods are suggested as a tool for providing parameters sensitive to this mass flow in a contact-free and non-invasive way. For the example of bubble-forming hydrogen peroxide decomposition in an alumina pellet, the dependence of the mean-squared displacement of fluid molecules on spatial direction, observation time and reaction time is presented, and multi-pulse techniques are employed in order to separate molecular displacements from coherent and incoherent motion on the timescale of the experiment. The reaction progress is followed until the complete decomposition of H 2O 2.

  15. Response surface methodology and process optimization of sustained release pellets using Taguchi orthogonal array design and central composite design

    PubMed Central

    Singh, Gurinder; Pai, Roopa S.; Devi, V. Kusum

    2012-01-01

    Furosemide is a powerful diuretic and antihypertensive drug which has low bioavailability due to hepatic first pass metabolism and has a short half-life of 2 hours. To overcome the above drawback, the present study was carried out to formulate and evaluate sustained release (SR) pellets of furosemide for oral administration prepared by extrusion/spheronization. Drug Coat L-100 was used within the pellet core along with microcrystalline cellulose as the diluent and concentration of selected binder was optimized to be 1.2%. The formulation was prepared with drug to polymer ratio 1:3. It was optimized using Design of Experiments by employing a 32 central composite design that was used to systematically optimize the process parameters combined with response surface methodology. Dissolution studies were carried out with USP apparatus Type I (basket type) in both simulated gastric and intestinal pH. The statistical technique, i.e., the two-tailed paired t test and one-way ANOVA of in vitro data has proposed that there was very significant (P≤0.05) difference in dissolution profile of furosemide SR pellets when compared with pure drug and commercial product. Validation of the process optimization study indicated an extremely high degree of prognostic ability. The study effectively undertook the development of optimized process parameters of pelletization of furosemide pellets with tremendous SR characteristics. PMID:22470891

  16. Direct injection method for HPLC/MS/MS analysis of acrylamide in aqueous solutions: application to adsorption experiments.

    PubMed

    Mnif, Ines; Hurel, Charlotte; Marmier, Nicolas

    2015-05-01

    Polyacrylamides are polymers used in many fields and represent the main source of release of the highly toxic acrylamide in the environment. In this work, a simple, rapid, and sensitive analytical method was developed with HPLC/MS/MS and direct injection for acrylamide analysis in water and adsorption samples. AFNOR standards NF T90-210 and NF T90-220 were used for the analytical method validation and uncertainty estimation. Limit of quantification (LOQ) for acrylamide was 1 μg/L, and accuracy was checked at three acrylamide levels (1, 6, and 10 μg/L). Uncertainties were estimated at 34.2, 22, and 12.4 % for acrylamide concentrations at LOQ, 6 μg/L, and 10 μg/L, respectively. Acrylamide adsorption on clays (kaolinite, illite) and sludge was then studied as a function of pH, time, and acrylamide concentrations. Acrylamide adsorption on kaolinite, illite, and sludge was found to be very weak since adsorption percentages were inferior to 10 %, whatever the pH value and the initial acrylamide concentration. The low affinity of acrylamide for clays and sludge is likely due to its hydrophilic property, small size, and charge neutrality.

  17. An Experiment to Test Geophysical Methods For Monitoring Fluid Re-Injection at the Wairakei Geothermal Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Jiracek, G. R.; Bowles-Martinez, E.; Feucht, D. W.; Ryan, J.; Caldwell, T. G.; Bannister, S. C.; Bertrand, T.; Bennie, S.; Bourguignon, S.

    2010-12-01

    The National Science Foundation (NSF) is supporting US students to participate in GNS Science’s geothermal research program supported by the New Zealand Government. The NSF international program aims to quick-start a new generation of geothermal-oriented US geophysics students who will be poised to be active participants and leaders in US geothermal energy development. This year’s project evaluated joint passive seismic and magnetotelluric (MT) field measurements to determine three-dimensional (3-D) reservoir characteristics during fluid withdrawal and re-injection. A preliminary test of the ability to achieve repeatable MT data in high noise locations was carried out in the Wairakei geothermal field using a 14-site base-line MT survey and repeat occupations at four sites. Different data processing schemes identified MT frequency bands where impedance phase tensor data were most sensitive to known variables such as daily solar source variations, wind, and drilling operations. Other frequency bands were identified where good MT repeatability will allow further tests. A streamlined method was developed for visualizing 3-D earthquake focal mechanisms resulting from production changes in geothermal reservoirs. The computer program allows spatial sorting of seismic events and thus subsurface fracture identification.

  18. Fecal Pellet Flux in the Mesopelagic Sargasso Sea

    NASA Astrophysics Data System (ADS)

    Koweek, D.; Shatova, O.; Conte, M. H.; Weber, J. C.

    2010-12-01

    The Oceanic Flux Program (OFP), located 75km SE of Bermuda, is the longest running sediment trap time-series of its kind, continually collecting deep sea particle flux since 1978. Recent application of digital microphotography to the size-fractionated OFP sediment trap material has generated a wealth of new quantitative visual information on particle flux composition, its changes with depth, and its temporal variability. We examined the fecal pellet flux at 1500m depth using image analysis of digital archives, in conjunction with data on the overlying surface ocean from the Bermuda Testbed Mooring (BTM) and the Bermuda Atlantic Time Series (BATS) programs, to investigate the role of mesoscale physical forcing on mesopelagic particle flux variability. During 2007, a productive cyclonic eddy, a mode water eddy and an anticyclonic eddy passed over the OFP site. Fecal pellet flux was enhanced during passage of both the cyclonic and mode water eddies. Total mass flux (TMF) was also enhanced during the productive cyclonic eddy, but was not influenced by the passage of the mode water eddy. No increase in fecal pellet flux or TMF was apparent during passage of the anticyclonic eddy despite indications of increased zooplankton abundance from ADCP backscatter intensity. Fecal pellet size frequency distributions indicate the presence of two, and sometimes three, distinct size classes. No seasonal trend in mean size of fecal pellets was observed for any size class, implying that the size distribution of the zooplankton populations producing the pellets is relatively constant throughout the year. We also investigated fecal pellet flux changes with depth at 500, 1500 and 3200m. Fecal pellet flux, and the fecal pellet contribution to TMF, were greatest at 500m and decreased with depth. The use of quantitative image analysis holds great potential as a powerful analytical tool in studies of marine particulate flux.

  19. Cleaning By Blasting With Pellets Of Dry Ice

    NASA Technical Reports Server (NTRS)

    Fody, Jody

    1993-01-01

    Dry process strips protective surface coats from parts to be cleaned, without manual scrubbing. Does not involve use of flammable or toxic solvents. Used to remove coats from variety of materials, including plastics, ceramics, ferrous and nonferrous metals, and composites. Adds no chemical-pollution problem to problem of disposal of residue of coating material. Process consists of blasting solid carbon dioxide (dry ice) pellets at surface to be cleaned. Pellets sublime on impact and pass into atmosphere as carbon dioxide gas. Size, harness, velocity, and quantity of pellets adjusted to suit coating material and substrate.

  20. ECCENTRIC ROLLING OF POWDER AND BONDING AGENT INTO SPHERICAL PELLETS

    DOEpatents

    Patton, G. Jr.; Zirinsky, S.

    1961-06-01

    A machine is described for pelletizing powder and bonding agent into spherical pellets of high density and uniform size. In this device, the material to be compacted is added to a flat circular pan which is moved in a circular orbit in a horizontal plane about an axis displaced from that of the pan's central axis without rotating the pan about its central axis. This movement causes the material contained therein to roll around the outside wall of the container and build up pellets of uniform shape, size, and density.

  1. Upcoming food-pellet reinforcement alters rats' lever pressing for liquid sucrose delivered by a progressive-ratio schedule.

    PubMed

    Weatherly, Jeffrey N.; King, Brent M.; Uran, Erin L.

    2003-06-30

    The present study investigated whether rats' responding for liquid-sucrose reinforcement delivered by a progressive-ratio (PR) schedule would be altered by the addition of food-pellet reinforcement available subsequent to the PR schedule. In Experiment 1, six rats lever pressed for 1% sucrose reinforcers delivered by a PR 3 schedule. In Experiment 2, six rats lever pressed for 5% sucrose delivered by a PR 5 schedule. In both experiments, baseline sessions consisted of 40min of exposure to the PR schedule. In the first treatment condition, a 25-min period of food-pellet reinforcement, delivered by a random-interval 60-s schedule, immediately followed the initial 40min. In the second treatment condition, the 25-min period of food-pellet reinforcement became available when 10min elapsed without the subject completing a ratio on the PR schedule. Results from both experiments showed that upcoming food-pellet reinforcement increased the number of ratios subjects completed on the PR schedule. Portions of the present results represent a partial replication of results reported by Baron and Derenne [J. Exp. Anal. Behav. 73 (2000) 291], who used a similar procedure. They also augment a growing body of research on positive induction.

  2. A qualitative study of experiences with and perceptions regarding long-acting injectable antipsychotics: Part I-patient perspectives.

    PubMed

    Iyer, Srividya; Banks, Nicola; Roy, Marc-André; Tibbo, Phil; Williams, Richard; Manchanda, Rahul; Chue, Pierre; Malla, Ashok

    2013-05-01

    Objectif : Malgré le problème largement reconnu de la mauvaise observance des antipsychotiques (AP), les injectables à action prolongée (IAP) qui pourraient améliorer l’observance sont sous-utilisés au Canada. Les attitudes à l’égard des IAP chez les patients et les psychiatres peuvent contribuer à cette sous-utilisation. Notre objectif était d’enquêter sur les perceptions et les attitudes des patients à l’égard des IAP au Canada. Méthode : Des groupes de discussion ont été formés de 34 patients ayant reçu un diagnostic de psychose du spectre de la schizophrénie dans 4 provinces canadiennes. Les groupes de discussion portaient sur les expériences avec les AP IAP et les attitudes à leur égard. Les séances ont fait l’objet d’un enregistrement sonore et ont été transcrites textuellement, et ces transcriptions ont été codées à l’aide d’une combinaison de méthodes déductives et inductives. Résultats : Quatre thèmes se sont dégagés : conscience et connaissance des IAP; perceptions des IAP; considérations concernant le coût et la commodité; et les questions liées au contexte coercitif dans lequel les IAP sont souvent prescrits. Neuf patients n’avaient jamais entendu parler des IAP, et d’autres ont déclaré ne pas avoir compris lorsqu’on a discuté avec eux des IAP. Les patients avaient habituellement entendu parler des IAP dans un contexte soit de coercition, soit de non-observance des médicaments. Les patients avaient des perceptions positives et négatives à l’égard des IAP. Les perceptions positives étaient axées sur la prévention de la rechute et l’effort réduit pour maintenir l’observance, et les perceptions négatives portaient sur les coûts financiers et la complication des rendez-vous pour recevoir les injections. Conclusion : Afin d’accroître l’utilisation des IAP, il faut aborder certaines questions, notamment l’insuffisance de l’information donnée aux patients, l

  3. Low mortality but increasing incidence of Staphylococcus aureus endocarditis in people who inject drugs: Experience from a Swedish referral hospital.

    PubMed

    Asgeirsson, Hilmir; Thalme, Anders; Weiland, Ola

    2016-12-01

    Staphylococcus aureus is a leading cause of infective endocarditis in people who inject drugs (PWID). The management of S aureus endocarditis (SAE) in PWID can be problematic. The objective of this retrospective observational study was to assess the epidemiology, clinical characteristics, and mortality of S aureus endocarditis (SAE) in PWID in Stockholm, Sweden.The Department of Infectious Diseases at the Karolinska University Hospital serves as a regional referral center for drug users with severe infections. Patients with active intravenous drug use treated for SAE at the department between January 2004 and December 2013 were retrospectively identified. Clinical and microbiological data were obtained from medical records and the diagnosis verified according to the modified Duke criteria.In total, 120 SAE episodes related to intravenous drug use were identified. Its incidence in Stockholm was 0.76/100,000 adult person-years for the entire period, increasing from 0.52/100,000 person-years in 2004 to 2008 to 0.99 in 2009 to 2013 (P = 0.02). The SAE incidence among PWID specifically was 249 (range 153-649) /100,000 person-years. Forty-two (35%) episodes were left-sided, and multiple valves were involved in 26 (22%). Cardiac valve surgery was performed in 10 (8%) episodes, all left-sided. The in-hospital and 1-year mortality rates were 2.5% (3 deaths) and 8.0% (9 deaths), respectively.We noted a high and increasing incidence over time of SAE related to intravenous drug use in Stockholm. The increased incidence partly reflects a rising number of PWID during the study period. The low mortality noted, despite a substantial proportion with left-sided endocarditis, probably in part reflects the quality of care obtained at a large and specialized referral center for drug users with severe infections.

  4. Validation of single-fluid and two-fluid magnetohydrodynamic models of the helicity injected torus spheromak experiment with the NIMROD code

    SciTech Connect

    Akcay, Cihan; Victor, Brian S.; Jarboe, Thomas R.; Kim, Charlson C.

    2013-08-15

    We present a comparison study of 3-D pressureless resistive MHD (rMHD) and 3-D presureless two-fluid MHD models of the Helicity Injected Torus with Steady Inductive helicity injection (HIT-SI). HIT-SI is a current drive experiment that uses two geometrically asymmetric helicity injectors to generate and sustain toroidal plasmas. The comparable size of the collisionless ion skin depth d{sub i} to the resistive skin depth predicates the importance of the Hall term for HIT-SI. The simulations are run with NIMROD, an initial-value, 3-D extended MHD code. The modeled plasma density and temperature are assumed uniform and constant. The helicity injectors are modeled as oscillating normal magnetic and parallel electric field boundary conditions. The simulations use parameters that closely match those of the experiment. The simulation output is compared to the formation time, plasma current, and internal and surface magnetic fields. Results of the study indicate 2fl-MHD shows quantitative agreement with the experiment while rMHD only captures the qualitative features. The validity of each model is assessed based on how accurately it reproduces the global quantities as well as the temporal and spatial dependence of the measured magnetic fields. 2fl-MHD produces the current amplification (I{sub tor}/I{sub inj}) and formation time τ{sub f} demonstrated by HIT-SI with similar internal magnetic fields. rMHD underestimates (I{sub tor}/I{sub inj}) and exhibits much a longer τ{sub f}. Biorthogonal decomposition (BD), a powerful mathematical tool for reducing large data sets, is employed to quantify how well the simulations reproduce the measured surface magnetic fields without resorting to a probe-by-probe comparison. BD shows that 2fl-MHD captures the dominant surface magnetic structures and the temporal behavior of these features better than rMHD.

  5. The development of an injection-molding process for a polyanhydride implant containing gentamicin sulfate.

    PubMed

    Deng, Jone-Shin; Meisters, Marts; Li, Luk; Setesak, Jeff; Claycomb, Lee; Tian, Youqin; Stephens, Dennis; Widman, Matt

    2002-01-01

    A production-scale manufacturing process has been developed for polyanhydride/gentamicin sulfate implants for the treatment of osteomyelitis. Gentamicin sulfate was first dried to an acceptable moisture level by using a tumble vacuum dryer. Dried gentamicin sulfate powder and polyanhydride granules were separately fed into the twin-screw extruder at a pre-determined metering rate using a gravimetric feeding device. The extruded molten mixture was solidified to form strands which were subsequently cut into pellets by using a pelletizer. The pellets were characterized with respect to copolymer molecular weight and drug content uniformity. The pellets were later fed into production-scale injection-molding equipment for implant fabrication. The injection-molding cycle was developed and evaluated in terms of cycle reproducibility. Implants were tested and shown to yield an oriented skin-core structure exhibiting a desirable in-vitro drug release profile.

  6. Preliminary Results from Downhole Osmotic Samplers in a Gas Tracer Injection Experiment in the Upper Oceanic Crust on the Eastern Flank of the Juan de Fuca Ridge.

    NASA Astrophysics Data System (ADS)

    de Jong, M. T.; Clark, J. F.; Neira, N. M.; Fisher, A. T.; Wheat, C. G.

    2015-12-01

    We present results from a gas tracer injection experiment in the ocean crust on the eastern flank of the Juan de Fuca Ridge, in an area of hydrothermal circulation. Sulfur hexafluoride (SF6) tracer was injected in Hole 1362B in 2010, during IODP Expedition 327. Fluid samples were subsequently collected from a borehole observatory (CORK) installed in this hole and similar CORKs in three additional holes (1026B, 1362A, and 1301A), located 300 to 500 m away. This array of holes is located on 3.5 My old seafloor, as an array oriented subparallel to the Endeavor Segment of Juan de Fuca Ridge. Borehole fluid samples were collected in copper coils using osmotic pumps. In addition to pumps at seafloor wellheads, downhole sampling pumps were installed in the perforated casing in the upper ocean crust. These downhole samplers were intended to produce a high-resolution continuous record of tracer concentrations, including records from the first year after tracer injection in Holes 1362A and 1362B. In contrast, wellhead samplers were not installed on these CORKs holes until 2011, and wellhead records from all CORKs have a record gap of up to one year, because of a delayed expedition in 2012. The downhole samples were recovered with the submersible Alvin in August 2014. SF6 concentrations in downhole samples recovered in 2014 are generally consistent with data obtained from wellhead samples. Of particular interest are the results from Hole 1362B, where a seafloor valve was opened and closed during various recovery expeditions. High resolution tracer curves produced from the 1362B downhole samples confirm that these operations produced an SF6 breakthrough curve corresponding to a classic push-pull test used to evaluate contaminant field locations in terrestrial setting. Complete analyses of downhole samples from these CORKs are expected to produce high-resolution breakthrough curves that will allow more precise analysis and modeling of hydrothermal flow in the study area.

  7. Effects of pelletized anticoagulant rodenticides on California quail

    USGS Publications Warehouse

    Blus, L.J.; Henny, C.J.; Grove, R.A.

    1985-01-01

    A moribund, emaciated California quail (Callipepla californica) that was found in an orchard in the state of Washington had an impacted crop and gizzard. Pellets containing the anticoagulant chlorophacinone (Rozol, RO) were in the crop; the gizzard contents consisted of a pink mass of paraffin that was selectively accumulated from the paraffinized pellets. The plasma prothrombin time of 28 sec was near that determined for control quail. The signs of RO intoxication seen in the moribund wild quail were duplicated in captive quail given ad libitum diets of either RO or another paraffinized chlorophacinone pellet (Mr. Rat Guard II, MRG). This left little doubt that paraffin impaction of the gizzard was the primary problem. All captive quail fed RO or MRG pellets showed no increases in prothrombin times compared to control values, died in an emaciated condition, and had gizzards impacted with paraffin.

  8. Role of shielding in modelling cryogenic deuterium pellet ablation

    NASA Astrophysics Data System (ADS)

    Gál, K.; Belonohy, É.; Kocsis, G.; Lang, P. T.; Veres, G.; ASDEX Upgrade Team

    2008-08-01

    For the better characterization of pellet ablation, the numerical LLP code has been enhanced by combining two relevant shielding mechanisms: that of the spherically expanding neutral cloud surrounding the pellet and that of the field elongated ionized material forming a channel flow. In contrast to our expectation the presence of the channel flow can increase the ablation rate although it reduces the heat flux travelling through it. The contribution of the different shielding effect in the ablation process is analysed for several pellet and plasma parameters and an ablation rate scaling is presented based on simple regression in the ASDEX Upgrade pellet and plasma parameter range. Finally the simulated results are compared with experimental data from typical ASDEX Upgrade discharges.

  9. Solvent-free cleaning using a centrifugal cryogenic pellet accelerator

    SciTech Connect

    Haines, J.R.; Fisher, P.W.; Foster, C.A.

    1995-06-01

    An advanced centrifuge that accelerates frozen CO{sub 2} pellets to high speeds for surface cleaning and paint removal is being developed at the Oak Ridge National Laboratory. The centrifuge-based accelerator was designed, fabricated, and tested under a program sponsored by the Warner Robins Air Logistics Center, Robins Air Force Base, Georgia. In comparison to the more conventional compressed air ``sandblast`` pellet accelerators, the centrifugal accelerator system can achieve higher pellet speeds, has precise speed control, and is more than ten times as energy efficient. Furthermore, the use of frozen CO{sub 2} pellets instead of conventional metal, plastic, sand, or other abrasive materials that remain solid at room temperature, minimizes the waste stream. This apparatus has been used to demonstrate cleaning of various surfaces, including removal of paint, oxide coatings, metal coatings, organic coatings, and oil and grease coatings from a variety of surfaces. The design and operation of the apparatus is discussed.

  10. Alternative Bioenergy: Small Scale Pellet Production from Forest Residues

    NASA Astrophysics Data System (ADS)

    Cochran, Audra S.

    Forests can readily supply feedstock for alternative bioenergy production. Feedstock removal has the potential to benefit forest health and provide ecosystem services, while also generating profit for landowners, contractors and forest managers. However, many landowners are faced with the challenge of managing forest residuals to meet slash compliances and fire regulations. Currently, most residuals are burned or left on site to decompose. Every year, the north-central Idaho region produces over 16 million dry tons of unutilized forest residues. In a time where alternative energy sources are growing in demand, new approaches to utilize these residuals for bioenergy production are being examined. One approach is a portable, small-scale wood pellet mill that can be taken directly to the logging site. Utilizing forest residues for pellet production reduces residue burning and its potential negative impacts on air quality. This presentation focuses on the quality of wood pellets manufactured by a portable wood pellet mill utilizing various forms of forest residuals.

  11. Effect of sericea lespedeza leaf meal pellets on adult female Haemonchus contortus in goats.

    PubMed

    Kommuru, D S; Whitley, N C; Miller, J E; Mosjidis, J A; Burke, J M; Gujja, S; Mechineni, A; Terrill, T H

    2015-01-15

    Sericea lespedeza (SL; Lespedeza cuneata) is a perennial warm-season forage rich in condensed tannins (CT) that has been reported to have anthelmintic activity against small ruminant gastrointestinal nematodes (GIN), particularly Haemonchus contortus, a highly pathogenic blood-feeder, but the mechanism of action of CT against H. contortus is not clearly understood. An experiment with young goats was designed to study the effect of SL leaf meal pellets on (1) a mature H. contortus infection, and (2) the surface appearance of adult H. contortus female worms. Thirty-six female and castrated male Boer crossbred goats artificially infected with H. contortus larvae were fed 75% SL leaf meal pellets or alfalfa pellets (18 goats/treatment group) in a 28-day confinement feeding trial. Fecal and blood samples were collected weekly for fecal egg count (FEC) and packed cell volume (PCV) determination, respectively, and all goats were slaughtered at the end of the trial for adult GIN recovery and counting. Five adult female H. contortus were recovered from the abomasum of two goats from each treatment group and from a prior study in which 75% and 95% SL leaf meal pellets or a commercial feed pellet were group-fed to grazing goats (270 days old, Spanish males, 10/treatment group) at 0.91 kg/head/d for 11 weeks. Adult GIN collected were fixed and examined for evidence of surface damage using scanning electron microscopy. Feeding 75% SL pellets to young goats in confinement reduced (P<0.05) FEC compared with control animals, while total worm numbers and PCV were not influenced by treatment. Three out of the 5 adult H. contortus recovered from SL treatment goats in the confinement feeding trial had cuticular surface damage, while no damage was observed on worms from the control group. All five worms observed from both SL treatments in the grazing study showed a shrunken, disheveled cuticular surface, whereas this was not observed on worms from control animals. Overall, this work

  12. MREIT experiments with 200 µA injected currents: a feasibility study using two reconstruction algorithms, SMM and harmonic B(Z).

    PubMed

    Arpinar, V E; Hamamura, M J; Degirmenci, E; Muftuler, L T

    2012-07-07

    Magnetic resonance electrical impedance tomography (MREIT) is a technique that produces images of conductivity in tissues and phantoms. In this technique, electrical currents are applied to an object and the resulting magnetic flux density is measured using magnetic resonance imaging (MRI) and the conductivity distribution is reconstructed using these MRI data. Currently, the technique is used in research environments, primarily studying phantoms and animals. In order to translate MREIT to clinical applications, strict safety standards need to be established, especially for safe current limits. However, there are currently no standards for safe current limits specific to MREIT. Until such standards are established, human MREIT applications need to conform to existing electrical safety standards in medical instrumentation, such as IEC601. This protocol limits patient auxiliary currents to 100 µA for low frequencies. However, published MREIT studies have utilized currents 10-400 times larger than this limit, bringing into question whether the clinical applications of MREIT are attainable under current standards. In this study, we investigated the feasibility of MREIT to accurately reconstruct the relative conductivity of a simple agarose phantom using 200 µA total injected current and tested the performance of two MREIT reconstruction algorithms. These reconstruction algorithms used are the iterative sensitivity matrix method (SMM) by Ider and Birgul (1998 Elektrik 6 215-25) with Tikhonov regularization and the harmonic B(Z) proposed by Oh et al (2003 Magn. Reason. Med. 50 875-8). The reconstruction techniques were tested at both 200 µA and 5 mA injected currents to investigate their noise sensitivity at low and high current conditions. It should be noted that 200 µA total injected current into a cylindrical phantom generates only 14.7 µA current in imaging slice. Similarly, 5 mA total injected current results in 367 µA in imaging slice. Total

  13. QUALITY OF WOOD PELLETS PRODUCED IN BRITISH COLUMBIA FOR EXPORT

    SciTech Connect

    Tumuluru, J.S.; Sokhansanj, Shahabaddine; Lim, C. Jim; Bi, X.T.; Lau, A.K.; Melin, Staffan; Oveisi, E.; Sowlati, T.

    2010-11-01

    Wood pellet production and its use for heat and power production are increasing worldwide. The quality of export pellets has to consistently meet certain specifications as stipulated by the larger buyers, such as power utilities or as specified by the standards used for the non-industrial bag market. No specific data is available regarding the quality of export pellets to Europe. To develop a set of baseline data, wood pellets were sampled at an export terminal in Vancouver, British Columbia, Canada. The sampling period was 18 months in 2007-2008 when pellets were transferred from storage bins to the ocean vessels. The sampling frequency was once every 1.5 to 2 months for a total of 9 loading/shipping events. The physical properties of the wood pellets measured were moisture content in the range of 3.5% to 6.5%, bulk density from 728 to 808 kg/m3, durability from 97% to 99%, fines content from 0.03% to 0.87%, calorific value as is from 17 to almost 18 MJ/kg, and ash content from 0.26% to 0.93%.The diameter and length were in the range of 6.4 to 6.5 mm and 14.0 to 19.0 mm, respectively. All of these values met the published non-industrial European grades (CEN) and the grades specified by the Pellet Fuel Institute for the United States for the bag market. The measured values for wood pellet properties were consistent except the ash content values decreased over the test period.

  14. Quality of Wood Pellets Produced in British Columbia for Export

    SciTech Connect

    J. S. Tumuluru; S. Sokhansanj; C. J. Lim; T. Bi; A. Lau; S. Melin; T. Sowlati; E. Oveisi

    2010-11-01

    Wood pellet production and its use for heat and power production are increasing worldwide. The quality of export pellets has to consistently meet certain specifications as stipulated by the larger buyers, such as power utilities or as specified by the standards used for the non-industrial bag market. No specific data is available regarding the quality of export pellets to Europe. To develop a set of baseline data, wood pellets were sampled at an export terminal in Vancouver, British Columbia, Canada. The sampling period was 18 months in 2007-2008 when pellets were transferred from storage bins to the ocean vessels. The sampling frequency was once every 1.5 to 2 months for a total of 9 loading/shipping events. The physical properties of the wood pellets measured were moisture content in the range of 3.5% to 6.5%, bulk density from 728 to 808 kg/m3, durability from 97% to 99%, fines content from 0.03% to 0.87%, calorific value as is from 17 to almost 18 MJ/kg, and ash content from 0.26% to 0.93%.The diameter and length were in the range of 6.4 to 6.5 mm and 14.0 to 19.0 mm, respectively. All of these values met the published non-industrial European grades (CEN) and the grades specified by the Pellet Fuel Institute for the United States for the bag market. The measured values for wood pellet properties were consistent except the ash content values decreased over the test period.

  15. Cesium powder and pellets inner container decontamination method determination

    SciTech Connect

    Ferrell, P.C.

    1998-07-09

    The cesium powder and pellets inner container is to be performance tested per the criteria specified in Section 4.0 of HNF-2399, ``Design, Fabrication, and Assembly Criteria for Cesium Powder and Pellet Inner Container.`` The test criteria specifies that the inner container be water tight during decontamination of the exterior surface. Three prototypes will be immersed into a pool of water to simulate a water decontamination process.

  16. Measurement of persistent organic pollutants (POPs) in plastic resin pellets from remote islands: toward establishment of background concentrations for International Pellet Watch.

    PubMed

    Heskett, Marvin; Takada, Hideshige; Yamashita, Rei; Yuyama, Masaki; Ito, Maki; Geok, Yeo Bee; Ogata, Yuko; Kwan, Charita; Heckhausen, Angelika; Taylor, Heidi; Powell, Taj; Morishige, Carey; Young, Doug; Patterson, Hugh; Robertson, Bryson; Bailey, Elizabeth; Mermoz, Jorge

    2012-02-01

    Plastic resin pellets collected from remote islands in the Pacific, Atlantic, and Indian Oceans and the Caribbean Sea were analyzed for polychlorinated biphenyls (PCBs), dichloro-diphenyltrichloroethane and its degradation products (DDTs), and hexachlorocyclohexanes (HCHs). Concentrations of PCBs (sum of 13 congeners) in the pellets were 0.1-9.9 ng/g-pellet. These were 1-3 orders of magnitude smaller than those observed in pellets from industrialized coastal shores. Concentrations of DDTs in the pellets were 0.8-4.1 ng/g-pellet. HCH concentrations were 0.6-1.7 ng/g-pellet, except for 19.3 ng/g-pellet on St. Helena, where current use of lindane is likely influence. This study provides background levels of POPs (PCBs<10 ng/g-pellet, DDTs <4 ng/g-pellet, HCHs <2 ng/g-pellet) for International Pellet Watch. Sporadic large concentrations of POPs were found in some pellet samples from remote islands and should be considered in future assessments of pollutants on plastic debris.

  17. A qualitative study of experiences with and perceptions regarding long-acting injectable antipsychotics: part II-physician perspectives.

    PubMed

    Iyer, Srividya; Banks, Nicola; Roy, Marc-André; Tibbo, Phil; Williams, Richard; Manchanda, Rahul; Chue, Pierre; Malla, Ashok

    2013-05-01

    Objectif : Dans de nombreux pays, dont le Canada, seule une petite proportion de personnes souffrant de troubles psychotiques reçoit des antipsychotiques (AP) injectables à action prolongée (IAP), malgré leur efficacité démontrée et leurs avantages possibles d’améliorer les taux d’observance. Les attitudes des médecins à l’égard des IAP peuvent influencer leurs pratiques de prescription et subséquemment contribuer à la sous-utilisation des IAP. Ici, nous faisons le compte rendu d’une étude qualitative des perceptions et des attitudes à l’égard des IAP chez les médecins du Canada. Méthode : Des groupes de discussion ont été formés de 24 psychiatres dans 4 provinces canadiennes. Les groupes de discussion portaient sur les expériences avec les AP IAP et les attitudes à leur égard. Les séances ont fait l’objet d’un enregistrement sonore et ont été transcrites textuellement, et ces transcriptions ont été codées à l’aide d’une procédure hybride de méthodes déductives et inductives. Un questionnaire abrégé a été administré avant le groupe de discussion. Résultats : Les questionnaires précédant le groupe de discussion ont indiqué que les psychiatres de notre étude prescrivaient la formule orale des AP la plupart du temps, et qu’ils avaient une expérience limitée des IAP. Les groupes de discussion ont dégagé 4 principaux thèmes : une expérience et des connaissances limitées des IAP; les attitudes à l’égard des IAP (croyances que les patients ont des perceptions négatives à l’égard des IAP, préjugés personnels contre les aiguilles, et consensus à propos de certains avantages des IAP); les pratiques de prescription des IAP (généralement vus comme une option de derniers recours pour les patients ayant des antécédents de non-observance); et les obstacles pratiques (par exemple, coût, entreposage, et dotation en personnel) à l’utilisation des IAP. Conclusion : Plusieurs facteurs peuvent

  18. Advanced turbine/CO{sub 2} pellet accelerator

    SciTech Connect

    Foster, C.A.; Fisher, P.W.

    1994-09-01

    An advanced turbine/CO{sub 2} pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory. The program, sponsored by Warner Robins Air Logistics Center, Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air sandblast pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies. Applications include removal of epoxy-based points from aircraft and the cleaning of surfaces contaminated with toxic, hazardous, or radioactive substances. The lack of a secondary contaminated waste stream is of great benefit.

  19. Pelletization of biomass waste with potato pulp content

    NASA Astrophysics Data System (ADS)

    Obidziński, Sławomir

    2014-03-01

    This paper presents the results of a research on the influence of potato pulp content in a mixture with oat bran on the power demand of the pelletization process and on the quality of the produced pellets, in the context of use thereof as a heating fuel. The tests of the densification of the pulp and bran mixture were carried out on a work stand whose main element was a P-300 pellet mill with the `flat matrix-densification rolls' system. 24 h after the pellets left the working system, their kinetic durability was established with the use of a Holmen tester. The research results obtained in this way allowed concluding that increasing the potato pulp content in a mixture with oat bran from 15 to 20% caused a reduction of the power demand of the pellet mill. It was also established that as the pulp content in a mixture with oat bran increases from 15 to 25%, the value of the kinetic durability of the pellets determined using Holmen and Pfost methods decreases.

  20. Design of pellet surface grooves for fission gas plenum

    SciTech Connect

    Carter, T.J.; Jones, L.R.; Macici, N.; Miller, G.C.

    1986-01-01

    In the Canada deuterium uranium pressurized heavy water reactor, short (50-cm) Zircaloy-4 clad bundles are fueled on-power. Although internal void volume within the fuel rods is adequate for the present once-through natural uranium cycle, the authors have investigated methods for increasing the internal gas storage volume needed in high-power, high-burnup, experimental ceramic fuels. This present work sought to prove the methodology for design of gas storage volume within the fuel pellets - specifically the use of grooves pressed or machined into the relatively cool pellet/cladding interface. Preanalysis and design of pellet groove shape and volume was accomplished using the TRUMP heat transfer code. Postirradiation examination (PIE) was used to check the initial design and heat transfer assumptions. Fission gas release was found to be higher for the grooved pellet rods than for the comparison rods with hollow or unmodified pellets. This had been expected from the initial TRUMP thermal analyses. The ELESIM fuel modeling code was used to check in-reactor performance, but some modifications were necessary to accommodate the loss of heat transfer surface to the grooves. It was concluded that for plenum design purposes, circumferential pellet grooves could be adequately modeled by the codes TRUMP and ELESIM.

  1. Evaluating the ignition sensitivity of thermal battery heat pellets

    SciTech Connect

    Thomas, E.V.

    1993-09-01

    Thermal batteries are activated by the ignition of heat pellets. If the heat pellets are not sensitive enough to the ignition stimulus, the thermal battery will not activate, resulting in a dud. Thus, to assure reliable thermal batteries, it is important to demonstrate that the pellets have satisfactory ignition sensitivity by testing a number of specimens. There are a number of statistical methods for evaluating the sensitivity of a device to some stimulus. Generally, these methods are applicable to the situation in which a single test is destructive to the specimen being tested, independent of the outcome of the test. In the case of thermal battery heat pellets, however, tests that result in a nonresponse do not totally degrade the specimen. This peculiarity provides opportunities to efficiently evaluate the ignition sensitivity of heat pellets. In this paper, a simple strategy for evaluating heat pellet ignition sensitivity (including experimental design and data analysis) is described. The relatively good asymptotic and small-sample efficiencies of this strategy are demonstrated.

  2. Modeling operation mode of pellet boilers for residential heating

    NASA Astrophysics Data System (ADS)

    Petrocelli, D.; Lezzi, A. M.

    2014-11-01

    In recent years the consumption of wood pellets as energy source for residential heating lias increased, not only as fuel for stoves, but also for small-scale residential boilers that, produce hot water used for both space heating and domestic hot water. Reduction of fuel consumption and pollutant emissions (CO, dust., HC) is an obvious target of wood pellet boiler manufacturers, however they are also quite interested in producing low- maintenance appliances. The need of frequent maintenance turns in higher operating costs and inconvenience for the user, and in lower boiler efficiency and higher emissions also. The aim of this paper is to present a theoretical model able to simulate the dynamic behavior of a pellet boiler. The model takes into account many features of real pellet boilers. Furthermore, with this model, it is possible to pay more attention to the influence of the boiler control strategy. Control strategy evaluation is based not only on pellet consumption and on total emissions, but also on critical operating conditions such as start-up and stop or prolonged operation at substantially reduced power level. Results are obtained for a residential heating system based on a wood pellet boiler coupled with a thermal energy storage. Results obtained so far show a weak dependence of performance in terms of fuel consumption and total emissions on control strategy, however some control strategies present some critical issues regarding maintenance frequency.

  3. Arthroscopic Removal of Shotgun Pellet From Within the Medial Meniscus

    PubMed Central

    Lacy, Kyle; Cooke, Chris; Cooke, Pat; Tonnos, Frederick

    2016-01-01

    Arthroscopic techniques are effective for the removal of intra-articular bullet and metal fragments after gunshot wounds to the shoulder, hip, knee, and sacroiliac joints. Surgical removal of bullets retained within the synovial joints is indicated; lead is dissolved by synovial fluid over time, leading to proliferative synovitis, lead arthropathy, elevated serum lead levels, and lead toxicity. We present an arthroscopic technique for removal of a shotgun pellet retained within the medial meniscus. In this technique, diagnostic knee arthroscopy is initially performed, which allows for localization of the pellet within the medial meniscus. An up-biter is used to resect the inner rim of meniscus surrounding the pellet, and the pellet is removed with a grasper. This arthroscopic approach is advantageous because it allows for efficient visualization of the pellet within the meniscus, thorough visualization of all compartments of the knee, a reduction in blood loss, and a decrease in surgical morbidity to the surrounding cartilaginous, neurovascular, and soft-tissue structures. This technique may therefore be one option to address bullet fragments or shotgun pellets that are retained within the medial meniscus. PMID:27073774

  4. An anaerobic field injection experiment in a landfill leachate plume, Grindsted, Denmark: 2. Deduction of anaerobic (methanogenic, sulfate-, and Fe (III)-reducing) redox conditions

    NASA Astrophysics Data System (ADS)

    Albrechtsen, Hans-JøRgen; Bjerg, Poul L.; Ludvigsen, Liselotte; Rügge, Kirsten; Christensen, Thomas H.

    1999-04-01

    Redox conditions may be environmental factors which affect the fate of the xenobiotic organic compounds. Therefore the redox conditions were characterized in an anaerobic, leachate-contaminated aquifer 15-60 m downgradient from the Grindsted Landfill, Denmark, where an field injection experiment was carried out. Furthermore, the stability of the redox conditions spatially and over time were investigated, and different approaches to deduce the redox conditions were evaluated. The redox conditions were evaluated in a set of 20 sediment and groundwater samples taken from locations adjacent to the sediment samples. Samples were investigated with respect to groundwater chemistry, including hydrogen and volatile fatty acids (VFAs) and sediment geochemistry, and bioassays were performed. The groundwater chemistry, including redox sensitive species for a large number of samples, varied over time during the experimental period of 924 days owing to variations in the leachate from the landfill. However, no indication of change in the redox environment resulting from the field injection experiment or natural variation was observed in the individual sampling points. The methane, Fe(II), hydrogen, and VFA groundwater chemistry parameters strongly indicated a Fe(III)-reducing environment. This was further supported by the bioassays, although methane production and sulfate-reduction were also observed in a few samples close to the landfill. On the basis of the calculated carbon conversion, Fe(III) was the dominant electron acceptor in the region of the aquifer, which was investigated. Because of the complexity of a landfill leachate plume, several redox processes may occur simultaneously, and an array of methods must be applied for redox characterization in such multicomponent systems.

  5. Arresting and supplying apparatus for increasing pellet impact drilling speed per run

    NASA Astrophysics Data System (ADS)

    Kovalyov, A. V.; Isaev, Ye D.; Veryevkin, A. V.; Gorbenko, V. M.; Ulyanova, O. S.

    2015-11-01

    The paper describes pellet impact drilling which might be used to increase the drilling rate and the penetration rate of hard and tough rock drilling. Pellet impact drilling implies rock destruction by metal pellets having high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are recirculated in the bottom of the bore hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The arresting and supplying apparatus is supposed to increase speed per run in pellet impact drilling, as it not only replenishes the pellets but also supplies and then picks up the pellets from the bottom hole. The paper presents the design of the pellet-supplying component which ensures a portion of pellets supply to the bottom hole.

  6. Use of pelleted sericea lespedeza (Lespedeza cuneata) for natural control of coccidia and gastrointestinal nematodes in weaned goats.

    PubMed

    Kommuru, D S; Barker, T; Desai, S; Burke, J M; Ramsay, A; Mueller-Harvey, I; Miller, J E; Mosjidis, J A; Kamisetti, N; Terrill, T H

    2014-08-29

    Infection with Eimeria spp. (coccidia) can be devastating in goats, particularly for young, recently-weaned kids, resulting in diarrhea, dehydration, and even death. Feeding dried sericea lespedeza [SL; Lespedeza cuneata (Dum.-Cours.) G. Don.] to young goats has been reported to reduce the effects of internal parasites, including gastrointestinal nematodes (GIN) but there have been no reports of the effects of feeding this forage on Eimeria spp. in goats. Two confinement feeding experiments were completed on recently-weaned intact bucks (24 Kiko-cross, Exp. 1; 20 Spanish, Exp. 2) to determine effects of SL pellets on an established infection of GIN and coccidia. The bucks were assigned to 1 of 2 (Exp. 1) or 3 (Exp. 2) treatment groups based upon the number of Eimeria spp. oocysts per gram (OPG) of feces. In Exp. 1, the kids were fed 1 of 2 pelleted rations ad libitum; 90% SL leaf meal+10% of a liquid molasses/lignin binder mix and a commercial pellet with 12% crude protein (CP) and 24% acid detergent fiber (n=12/treatment group, 2 animals/pen). For Exp. 2, treatment groups were fed (1) 90% SL leaf meal pellets from leaves stored 3 years (n=7), (2) 90% SL pellets from leaf meal stored less than 6 months, (n=7), and the commercial pellets (n=6) ad libitum. For both trials, fecal and blood samples were taken from individual animals every 7 days for 28 days to determine OPG and GIN eggs per gram (EPG) and packed cell volume (PCV), respectively. In Exp. 2, feces were scored for consistency (1=solid pellets, 5=slurry) as an indicator of coccidiosis. In Exp. 1, EPG (P<0.001) and OPG (P<0.01) were reduced by 78.7% and 96.9%, respectively, 7 days after initiation of feeding in goats on the SL pellet diet compared with animals fed the control pellets. The OPG and EPG remained lower in treatment than control animals until the end of the trial. In Exp. 2, goats fed new and old SL leaf meal pellets had 66.2% and 79.2% lower (P<0.05) EPG and 92.2% and 91.2% lower (P<0.05) OPG

  7. High-Intensity Radiated Field Fault-Injection Experiment for a Fault-Tolerant Distributed Communication System

    NASA Technical Reports Server (NTRS)

    Yates, Amy M.; Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Gonzalez, Oscar R.; Gray, W. Steven

    2010-01-01

    Safety-critical distributed flight control systems require robustness in the presence of faults. In general, these systems consist of a number of input/output (I/O) and computation nodes interacting through a fault-tolerant data communication system. The communication system transfers sensor data and control commands and can handle most faults under typical operating conditions. However, the performance of the closed-loop system can be adversely affected as a result of operating in harsh environments. In particular, High-Intensity Radiated Field (HIRF) environments have the potential to cause random fault manifestations in individual avionic components and to generate simultaneous system-wide communication faults that overwhelm existing fault management mechanisms. This paper presents the design of an experiment conducted at the NASA Langley Research Center's HIRF Laboratory to statistically characterize the faults that a HIRF environment can trigger on a single node of a distributed flight control system.

  8. Testing phenanthrene distribution properties of virgin plastic pellets and plastic eroded pellets found on Lesvos island beaches (Greece).

    PubMed

    Karapanagioti, Hrissi K; Klontza, Irene

    2008-05-01

    Plastic pellets have been characterized as toxic pollutant carriers throughout the world oceans and coastal zones. However, their sorptive properties are not yet well understood. In the present study, virgin pellets and plastic eroded pellets (PEP) are used to elucidate their distribution characteristics through distribution kinetic studies. Distribution occurs through diffusion into the pellet for all materials (polyethylene, polyoxymethylene, and PEP) except polypropylene (PP). Although diffusion into the polymer happens with similar rates for both freshwater and saltwater external solutions, apparent diffusion is dependent on the solution salinity because it results in higher equilibrium distribution coefficients. Distribution coefficient into the PEP is higher and diffusion is slower than into the virgin materials. This is attributed to increased crystallinity of the PEP due to weathering. PP demonstrates diffusion rates that are increased by salinity and is apparently faster than into the other polymers suggesting a surface diffusion process.

  9. Detection and recognition of uneaten fish food pellets in aquaculture using image processing

    NASA Astrophysics Data System (ADS)

    Liu, Huanyu; Xu, Lihong; Li, Dawei

    2015-03-01

    The waste of fish food has always been a serious problem in aquaculture. On one hand, the leftover fish food spawns a big waste in the aquaculture industry because fish food accounts for a large proportion of the investment. On the other hand, the left over fish food may pollute the water and make fishes sick. In general, the reason for fish food waste is that there is no feedback about the consumption of delivered fish food after feeding. So it is extremely difficult for fish farmers to determine the amount of feedstuff that should be delivered each time and the feeding intervals. In this paper, we propose an effective method using image processing techniques to solve this problem. During feeding events, we use an underwater camera with supplementary LED lights to obtain images of uneaten fish food pellets on the tank bottom. An algorithm is then developed to figure out the number of left pellets using adaptive Otsu thresholding and a linear-time component labeling algorithm. This proposed algorithm proves to be effective in handling the non-uniform lighting and very accurate number of pellets are counted in experiments.

  10. Comparison of novel granulated pellet-containing tablets and traditional pellet-containing tablets by artificial neural networks.

    PubMed

    Huang, Ying; Yao, Qinghe; Zhu, Chune; Zhang, Xuan; Qin, Lingzhen; Wang, Qinruo; Pan, Xin; Wu, Chuanbin

    2015-01-01

    Novel granulated pellets technique was adopted to prepare granulated pellet-containing tablets (GPCT). GPCT and traditional pellet-containing tablets (PCT) were prepared according to 29 formulations devised by the Design Expert 7.0, with doxycycline hydrochloride as model drug, blends of Eudragit FS 30D and Eudragit L 30D-55 as coating materials, for the comparison study to confirm the superiority of GPCT during compaction. Eudragit FS 30D content, coating weight gain, tablet hardness and pellet size were chosen as influential factors to investigate the properties and drug release behavior of tablets. The correlation coefficients between the experimental values and the predicted values by artificial neural networks (ANNs) for PCT and GPCT were 0.9474 and 0.9843, respectively, indicating the excellent prediction of ANNs. The similarity factors (f2) for release profiles of GPCT and the corresponding original pellets were higher than those of PCT, suggesting that the excipient layer of granulated pellets absorbed the compressing force and protected the integrity of coating films during compaction.

  11. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill

    PubMed Central

    Tumuluru, Jaya Shankar; Conner, Craig C.; Hoover, Amber N.

    2016-01-01

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was <4%, whereas the reduction was about 7-8% without the binder. With 4% binder and 33% (w.b.) feedstock moisture content, the bulk density and durability values observed of the dried pellets were >510 kg/m3 and >98%, respectively, and the percent fine particles generated was reduced to <3%. PMID:27340875

  12. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill.

    PubMed

    Tumuluru, Jaya Shankar; Conner, Craig C; Hoover, Amber N

    2016-06-15

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was <4%, whereas the reduction was about 7-8% without the binder. With 4% binder and 33% (w.b.) feedstock moisture content, the bulk density and durability values observed of the dried pellets were >510 kg/m(3) and >98%, respectively, and the percent fine particles generated was reduced to <3%.

  13. Initial experience with dual-lumen balloon catheter injection for preoperative Onyx embolization of skull base paragangliomas.

    PubMed

    Ladner, Travis R; He, Lucy; Davis, Brandon J; Yang, George L; Wanna, George B; Mocco, J

    2016-06-01

    OBJECT Paragangliomas are highly vascular head and neck tumors for which preoperative embolization is often considered to facilitate resection. The authors evaluated their initial experience using a dual-lumen balloon to facilitate preoperative embolization in 5 consecutive patients who underwent preoperative transarterial Onyx embolization assisted by the Scepter dual-lumen balloon catheter between 2012 and 2014. OBJECT The authors reviewed the demographic and clinical records of 5 patients who underwent Scepter-assisted Onyx embolization of a paraganglioma followed by resection between 2012 and 2014. Descriptive statistics of clinical outcomes were assessed. RESULTS Five patients (4 with a jugular and 1 with a vagal paraganglioma) were identified. Three paragangliomas were embolized in a single session, and each of the other 2 were completed in 3 staged sessions. The mean volume of Onyx used was 14.3 ml (range 6-30 ml). Twenty-seven vessels were selectively catheterized for embolization. All patients required selective embolization via multiple vessels. Two patients required sacrifice of parent vessels (1 petrocavernous internal carotid artery and 1 vertebral artery) after successful balloon test occlusion. One patient underwent embolization with Onyx-18 alone, 2 with Onyx-34 alone, and 1 with Onyx-18 and -34. In each case, migration of Onyx was achieved within the tumor parenchyma. The mean time between embolization and resection was 3.8 days (range 1-8 days). Gross-total resection was achieved in 3 (60%) patients, and the other 2 patients had minimal residual tumor. The mean estimated blood loss during the resections was 556 ml (range 200-850 ml). The mean postoperative hematocrit level change was -17.3%. Two patients required blood transfusions. One patient, who underwent extensive tumor penetration with Onyx, developed a temporary partial cranial nerve VII palsy that resolved to House-Brackmann Grade I (out of VI) at the 6-month follow-up. One patient

  14. Apparatus and method for classifying fuel pellets for nuclear reactor

    DOEpatents

    Wilks, Robert S.; Sternheim, Eliezer; Breakey, Gerald A.; Sturges, Jr., Robert H.; Taleff, Alexander; Castner, Raymond P.

    1984-01-01

    Control for the operation of a mechanical handling and gauging system for nuclear fuel pellets. The pellets are inspected for diameters, lengths, surface flaws and weights in successive stations. The control includes, a computer for commanding the operation of the system and its electronics and for storing and processing the complex data derived at the required high rate. In measuring the diameter, the computer enables the measurement of a calibration pellet, stores that calibration data and computes and stores diameter-correction factors and their addresses along a pellet. To each diameter measurement a correction factor is applied at the appropriate address. The computer commands verification that all critical parts of the system and control are set for inspection and that each pellet is positioned for inspection. During each cycle of inspection, the measurement operation proceeds normally irrespective of whether or not a pellet is present in each station. If a pellet is not positioned in a station, a measurement is recorded, but the recorded measurement indicates maloperation. In measuring diameter and length a light pattern including successive shadows of slices transverse for diameter or longitudinal for length are projected on a photodiode array. The light pattern is scanned electronically by a train of pulses. The pulses are counted during the scan of the lighted diodes. For evaluation of diameter the maximum diameter count and the number of slices for which the diameter exceeds a predetermined minimum is determined. For acceptance, the maximum must be less than a maximum level and the minimum must exceed a set number. For evaluation of length, the maximum length is determined. For acceptance, the length must be within maximum and minimum limits.

  15. Hot-melt extrusion of sugar-starch-pellets.

    PubMed

    Yeung, Chi-Wah; Rein, Hubert

    2015-09-30

    Sugar-starch-pellets (syn. sugar spheres) are usually manufactured through fluidized bed granulation or wet extrusion techniques. This paper introduces hot-melt extrusion (HME) as an alternative method to manufacture sugar-starch-pellets. A twin-screw extruder coupled with a Leistritz Micro Pelletizer (LMP) cutting machine was utilized for the extrusion of different types (normal-, waxy-, and high-amlyose) of corn starch, blended with varying amounts of sucrose. Pellets were characterized for their physicochemical properties including crystallinity, particle size distribution, tensile strength, and swelling expansion. Furthermore, the influence of sugar content and humidity on the product was investigated. Both sucrose and water lowered the Tg of the starch system allowing a convenient extrusion process. Mechanical strength and swelling behavior could be associated with varying amylose and amylopectin. X-ray powder diffractometric (XRPD) peaks of increasing sucrose contents appeared above 30%. This signified the oversaturation of the extruded starch matrix system with sucrose. Otherwise, had the dissolved sucrose been embedded into the molten starch matrix, no crystalline peak could have been recognized. The replacement of starch with sucrose reduced the starch pellets' swelling effect, which resulted in less sectional expansion (SEI) and changed the surface appearance. Further, a nearly equal tensile strength could be detected for sugar spheres with more than 40% sucrose. This observation stands in good relation with the analyzed values of the commercial pellets. Both techniques (fluidized bed and HME) allowed a high yield of spherical pellets (less friability) for further layering processes. Thermal influence on the sugar-starch system is still an obstacle to be controlled.

  16. The influence of grinding and pelleting of feed on the microbial composition and activity in the digestive tract of broiler chickens.

    PubMed

    Engberg, R M; Hedemann, M S; Jensen, B B

    2002-09-01

    1. The influence of feed grinding (coarsely or finely ground feed) and feed form (mash or pellets) on the intestinal environment was investigated in a growth experiment with broiler chickens taking the intestinal microflora, intestinal viscosity, and the activities of pancreatic digestive enzymes into consideration. 2. As compared to mash the feeding of pellets was associated with a significantly higher body weight due to increased feed intake and improved feed utilisation. 3. Pellet-fed birds had significantly decreased gizzard weights, a higher gizzard pH and a lower intestinal pH than mash-fed birds. 4. Pellet-fed birds had significantly lower relative pancreas weights and lower activities of pancreatic digestive enzymes (amylase, lipase, chymotrypsin), which indicates the existence of a feedback mechanism, which may have been triggered by the intestinal concentration of enzymatically hydrolysed products or of the respective digestive enzymes. 5. Pellet-fed birds had larger numbers of coliform bacteria and enterococci in the ileum and a reduced number of Clostridium perfringens and lactobacilli in the distal end of the digestive tract (caeca and rectum). Microbial fermentation in terms of volatile fatty acid (VFA) concentration was found to be significantly higher in the caeca of pellet-fed birds than in mash-fed birds.

  17. An anaerobic field injection experiment in a landfill leachate plume, Grindsted, Denmark: 1. Experimental setup, tracer movement, and fate of aromatic and chlorinated compounds

    NASA Astrophysics Data System (ADS)

    Rügge, Kirsten; Bjerg, Poul L.; Pedersen, JøRn K.; MosbæK, Hans; Christensen, Thomas H.

    1999-04-01

    A continuous, natural-gradient field injection experiment, involving 18 xenobiotic compounds and bromide as tracers, was performed in the anaerobic region of a leachate plume downgradient from the Grindsted Landfill, Denmark. The injection lasted for 195 days, and within this period a continuous cloud was established. Over a period of 924 days the cloud movement was monitored in approximately 70 discrete sampling points in the central part of the cloud, and the spatial distribution was described by seven cloud snapshots involving 400-700 sampling points. The bromide cloud movement closely followed the varying flow direction predicted by the water table measurements. Moment analysis showed decreasing tracer flow velocities and reduced capture of bromide mass with time, which may be explained by varying flow conditions (direction, hydraulic gradient) and the heterogeneous geological conditions in the sandy aquifer. Naphthalene, having the highest log Kow value, was the most retarded compound, with a retardation of less than 10%. Therefore sorption was not considered to be a significant attenuation process for any of the compounds studied. Transformation under iron-reducing conditions was observed for toluene, o-xylene, TeCM, 1,1,1-TCA, PCE, and TCE, while transformation of benzene and napthalene was not detected in the aquifer within the time frame of this study. First-order transformation rates were in the range of 0.028-0.039 d-1 and 0.0014-0.0028 d-1 for the aromatic compounds toluene and o-xylene, respectively. The rates for the chlorinated aliphatic compounds, tetrachloromethane, 1,1,1- trichloroethane, tetrachloroethylene, and trichloroethylene, were >0.7 d-1, 0.0044-0.0054 d-1, 0.0012-0.0038 d-1, and 0.0003-0.001 d-1, respectively. Long lag periods and slow transformation rates were observed for some of the compounds, suggesting that lack of transformation reported in the literature may be attributable to short experimental periods in those studies.

  18. Usability of the Novel Liraglutide 3.0 mg Pen Injector Among Overweight or Obese Adult Patients With or Without Prior Injection Experience

    PubMed Central

    Fujioka, Ken; Sparre, Thomas; Sun, Lily Yong-Hui; Krogsgaard, Susanne; Kushner, Robert F.

    2015-01-01

    Background: Obesity is associated with multiple comorbidities and increased mortality, making it an important target for treatment. However, achieving and maintaining weight loss by diet and physical activity remains challenging, and may often require pharmacotherapy. Liraglutide 3.0 mg has recently been approved for weight management in the United States, Canada, and EU. The current analysis used a summative usability test to assess safety and effectiveness, ease of use, and training requirements for the novel liraglutide 3.0 mg pen injector. Methods: Of the 234 participants, half received instructions for use and video-based training and/or opportunity to handle the device. All participants (excluding pharmacists) performed 6 tasks followed by post- task interviews on task difficulty, device ease of use, and any use errors, close calls, and operational difficulties. Tasks included differentiation of correct box and pen injector, medication clarity assessment, normal, dose reversal, and end-of-content injection. Number/type of use errors, close calls, and operational difficulties were evaluated. Results: All assessed participants interpreted the instructions for use correctly. No potentially serious use errors, and low numbers of nonserious errors, were reported. Overall, participants committed 105 use errors related to handling, with no potential for harm. A total of 25 close calls and 44 operational difficulties were reported without any pattern indicative of a design flaw. Marked differences in the incidence of events were observed for trained versus untrained participants regardless of prior injection experience. Participants rated ease of use as 6.4/7. Conclusions: The liraglutide 3.0 mg pen injector is safe and easy to use for liraglutide administration. New device features allow for safe use after brief training. PMID:26183599

  19. Certolizumab Injection

    MedlinePlus

    ... has not improved when treated with other medications, rheumatoid arthritis (a condition in which the body attacks its ... continues. When certolizumab injection is used to treat rheumatoid arthritis, it is usually given every other week and ...

  20. Natalizumab Injection

    MedlinePlus

    ... prevent episodes of symptoms in people who have Crohn's disease (a condition in which the body attacks the ... If you are receiving natalizumab injection to treat Crohn's disease, your symptoms should improve during the first few ...