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Sample records for iii metal liner

  1. Corrosion of Metal Modular Cup Liners.

    PubMed

    Hothi, Harry S; Ilo, Kevin; Whittaker, Robert K; Eskelinen, Antti; Skinner, John A; Hart, Alister J

    2015-09-01

    Numerous studies have reported on corrosion at the modular head taper, however less is known about the interface between the metal shell and liner of modular cups. This study examined the backside of a series of metal modular cup liners of two designs (DePuy Pinnacle and Smith & Nephew R3), retrieved from 67 patients. Visual inspection found evidence of corrosion in virtually all liners, with the engaging rim surface significantly more corroded than the polar regions (P<0.001). EDX confirmed that black surface deposits were chromium rich corrosion debris, while SEM analysis revealed considerable pitting in the vicinity of the black debris. The R3 liners were significantly more corroded that the Pinnacles (P<0.001); this may help to explain the higher revision rates of this design. PMID:25890504

  2. Corrosion of Metal Modular Cup Liners.

    PubMed

    Hothi, Harry S; Ilo, Kevin; Whittaker, Robert K; Eskelinen, Antti; Skinner, John A; Hart, Alister J

    2015-09-01

    Numerous studies have reported on corrosion at the modular head taper, however less is known about the interface between the metal shell and liner of modular cups. This study examined the backside of a series of metal modular cup liners of two designs (DePuy Pinnacle and Smith & Nephew R3), retrieved from 67 patients. Visual inspection found evidence of corrosion in virtually all liners, with the engaging rim surface significantly more corroded than the polar regions (P<0.001). EDX confirmed that black surface deposits were chromium rich corrosion debris, while SEM analysis revealed considerable pitting in the vicinity of the black debris. The R3 liners were significantly more corroded that the Pinnacles (P<0.001); this may help to explain the higher revision rates of this design.

  3. Expandable Metal Liner For Downhole Components

    DOEpatents

    Hall, David R.; Fox, Joe R.

    2004-10-05

    A liner for an annular downhole component is comprised of an expandable metal tube having indentations along its surface. The indentations are formed in the wall of the tube either by drawing the tube through a die, by hydroforming, by stamping, or roll forming and may extend axially, radially, or spirally along its wall. The indentations accommodate radial and axial expansion of the tube within the downhole component. The tube is inserted into the annular component and deformed to match an inside surface of the component. The tube may be expanded using a hydroforming process or by drawing a mandrel through the tube. The tube may be expanded in such a manner so as to place it in compression against the inside wall of the component. The tube is useful for improving component hydraulics, shielding components from contamination, inhibiting corrosion, and preventing wear to the downhole component during use. It may also be useful for positioning conduit and insulated conductors within the component. An insulating material may be disposed between the tube and the component in order to prevent galvanic corrosion of the downhole component.

  4. Heat dissipating nuclear reactor with metal liner

    DOEpatents

    Gluekler, Emil L.; Hunsbedt, Anstein; Lazarus, Jonathan D.

    1987-01-01

    Disclosed is a nuclear reactor containment including a reactor vessel disposed within a cavity with capability for complete inherent decay heat removal in the earth and surrounded by a cast steel containment member which surrounds the vessel. The member has a thick basemat in contact with metal pilings. The basemat rests on a bed of porous particulate material, into which water is fed to produce steam which is vented to the atmosphere. There is a gap between the reactor vessel and the steel containment member. The containment member holds any sodium or core debris escaping from the reactor vessel if the core melts and breaches the vessel.

  5. Mechanical failure of metal-polyethylene sandwich liner in metal-on-metal total hip replacement.

    PubMed

    Oshima, Yasushi; Fetto, Joseph F

    2015-01-01

    Metal-on-metal had been proposed as an optimal articulation in THRs, however, many monoblock prostheses have been recalled in the USA because of significant high rates of early failure. Metal-on-metal prostheses had been implanted in our institution, and this is a case history of a single patient, in whom metal-on-metal THRs with different femoral sizes of heads were implanted. A 57-year-old female patient underwent bilateral total hip replacements with metal-on-metal prostheses using metal-polyethylene "sandwich" liners 9 years ago on the right side and 7 years ago on the left side respectively. The only difference in both sides was the femoral head diameter of 28 mm in right and 34 mm in left. Seven years after the left surgery, the acetabular liner was dissociated, however, metallosis was not detected. Although the larger femoral head was thought to increase hip joint stability, it dictated a reduction in polyethylene thickness in this prosthesis design, and it was 4 mm in the left hip. Recently, metal-on-metal articulations are thought not to be optimal for hip joint bearing surface, however, this clinical failure was due to the polyethylene thickness and quality.

  6. Small gas turbine combustor experimental study: Compliant metal/ceramic liner and performance evaluation

    NASA Technical Reports Server (NTRS)

    Acosta, W. A.; Norgren, C. T.

    1986-01-01

    Combustor research relating to the development of fuel efficient small gas turbine engines capable of meeting future commercial and military aviation needs is currently underway at NASA Lewis. As part of this combustor research, a basic reverse-flow combustor has been used to investigate advanced liner wall cooling techniques. Liner temperature, performance, and exhaust emissions of the experimental combustor utilizing compliant metal/ceramic liners were determined and compared with three previously reported combustors that featured: (1) splash film-cooled liner walls; (2) transpiration cooled liner walls; and (3) counter-flow film cooled panels.

  7. Low-Speed Fan Noise Attenuation from a Foam-Metal Liner

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Jones, Michael G.

    2011-01-01

    A foam-metal liner for attenuation of fan noise was developed for and tested on a low-speed fan. This type of liner represents a significant advance over traditional liners, due to the possibility of placement in close proximity to the rotor. An advantage of placing treatment in this region is that the acoustic near field is modified, thereby inhibiting the noise-generation mechanism. This can result in higher attenuation levels than could be achieved by liners located in the nacelle inlet. In addition, foam-metal liners could potentially replace the fan rub strip and containment components, ultimately reducing engine components and thus weight, which can result in a systematic increase in noise reduction and engine performance. Foam-metal liners have the potential to reduce fan noise by 4 dB based on this study.

  8. Foam-Metal Liner Attenuation of Low-Speed Fan Noise

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel R.; Jones, Michael G.

    2008-01-01

    A foam-metal liner for attenuation of fan noise was developed for and tested on a low speed fan. This type of liner represents a significant advance over traditional liners due to the possibility for placement in close proximity to the rotor. An advantage of placing treatment in this region is the modification of the acoustic near field, thereby inhibiting noise generation mechanisms. This can result in higher attenuation levels than can be achieved by liners located in the nacelle inlet. In addition, foam-metal liners could potentially replace the fan rub-strip and containment components, ultimately reducing engine components and thus weight, which can result in a systematic increase in noise reduction and engine performance. Foam-metal liners have the potential to reduce fan noise by 4 dB based on this study.

  9. Corrosion on the acetabular liner taper from retrieved modular metal-on-metal total hip replacements.

    PubMed

    Gascoyne, Trevor C; Dyrkacz, Richard M; Turgeon, Thomas R; Burnell, Colin D; Wyss, Urs P; Brandt, Jan-M

    2014-10-01

    Eight retrieved metal-on-metal total hip replacements displayed corrosion damage along the cobalt-chromium alloy liner taper junction with the Ti alloy acetabular shell. Scanning electron microscopy indicated the primary mechanism of corrosion to be grain boundary and associated crevice corrosion, which was likely accelerated through mechanical micromotion and galvanic corrosion resulting from dissimilar alloys. Coordinate measurements revealed up to 4.3mm(3) of the cobalt-chromium alloy taper surface was removed due to corrosion, which is comparable to previous reports of corrosion damage on head-neck tapers. The acetabular liner-shell taper appears to be an additional source of metal corrosion products in modular total hip replacements. Patients with these prostheses should be closely monitored for signs of adverse reaction towards corrosion by-products.

  10. Autofrettage to Counteract Coefficient of Thermal Expansion Mismatch in Cryogenic Pressurized Pipes with Metallic Liners

    NASA Technical Reports Server (NTRS)

    Wen, Ed; Barbero, Ever; Tygielski, Phlip; Turner, James E. (Technical Monitor)

    2001-01-01

    Composite feedlines with metal liners have the potential to reduce weight/cost while providing the same level of permeation resistance and material compatibility of all-metal feedlines carrying cryogenic propellants in spacecraft. The major technical challenges are the large difference in Coefficient of Thermal Expansion between the liner and the composite, and the manufacturing method required to make a very thin liner with the required strength and dimensional tolerance. This study investigates the use of autofrettage (compressive preload) to counteract Coefficient of Thermal Expansion when pre-pressurization procedures cannot be used to solve this problem. Promising materials (aluminum 2219, Inconel 718, nickel, nickel alloy) and manufacturing techniques (chemical milling, electroplating) are evaluated to determine the best liner candidates. Robust, autofrettaged feedlines with a low Coefficient of Thermal Expansion liner (Inconel 718 or nickel alloy) are shown to successfully counteract mismatch at LOX temperature. A new concept, autofrettage by temperature, is introduced for high Coefficient of Thermal Expansion materials (aluminum and pure nickel) where pressure cannot be used to add compressive preload.

  11. Early failure of a polyethylene acetabular liner cemented into a metal cup.

    PubMed

    Wilson, David A J; Corkum, Joseph P; Teeter, Matthew G; Holdsworth, David W; Dunbar, Michael J

    2012-05-01

    In 2002, a patient underwent revision total hip arthroplasty for polyethylene wear. The acetabular cup was well fixed, and it was decided to cement a new polyethylene liner into the existing cup. In 2006, the patient presented with inability to weight bear and easy subluxation of the hip. Revision surgery was performed, and all components were examined postoperatively. Investigation with microcomputed tomography revealed that the liner had plastically deformed at the superior pole resulting in the hip instability. The reasons for this are suspected to be related to the abducted nature of the original cup and an uneven cement mantle. This report suggests that cementation of polyethylene liners into metal cups has limitations and is not appropriate in all circumstances.

  12. Attenuation of FJ44 Turbofan Engine Noise with a Foam-Metal Liner Installed Over-the-Rotor

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Elliott, Dave M.; Jones, Michael G.; Hartley, Thomas C.

    2009-01-01

    A Williams International FJ44-3A 3000-lb thrust class turbofan engine was used as a demonstrator for a Foam-Metal Liner (FML) installed in close proximity to the fan. Two FML designs were tested and compared to the hardwall baseline. Traditional single degree-of-freedom liner designs were also evaluated to provide a comparison. Farfield acoustic levels and limited engine performance results are presented in this paper. The results show that the FML achieved up to 5 dB Acoustic Power Level (PWL) overall attenuation in the forward quadrant, equivalent to the traditional liner design. An earlier report presented the test set-up and conditions.

  13. Azimuthal Current Density Distribution Resulting from a Power Feed Vacuum Gap in Metallic Liner Experiments at 1 MA

    NASA Astrophysics Data System (ADS)

    Bott-Suzuki, Simon; Cordaro, S. W.; Caballero Bendixsen, L. S.; Atoyan, L.; Byvank, T.; Potter, W.; Kusse, B. R.; Greenly, J. B.; Hammer, D. A.; Chittenden, J. P.; Jennings, C. A.

    2015-11-01

    We present a study investigating the initiation of plasma in solid, metallic liners where the liner thickness is large compared to the collisionless skin depth. A vacuum gap is introduced in the power feed and we investigate the effect of this on the azimuthal initiation of plasma in the liner. We present optical emission data from aluminum liners on the 1 MA, 100ns COBRA generator. We use radial and axial gated imaging and streak photography, which show a dependence of onset of emission with the size of a small power-feed vacuum gap. The evolution of ``hot-spots'' generated from breakdown vacuum gap evolves relatively slowly and azimuthal uniformity is not observed on the experimental time-scale. We also show measurements of the B-field both outside and inside the liner, using miniature Bdot probes, which show a dependence on the liner diameter and thickness, and a correlation to the details of the breakdown. These data will be compared to magneto-hydrodynamic simulations to infer how such non-uniformities may affect full liner implosion experiments.

  14. Collaboration with Williams International to Demonstrate the Characteristics of a Foam-Metal-Liner Installed Over-the-Rotor of a Turbofan Engine

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel; Elliott, Dave; Jones, Mike; Hartley, Tom

    2008-01-01

    A Williams International FJ44-3A 3000-lb thrust class turbofan engine was used as a demonstrator for foam-metal liner installed in close proximity to the fan. Two foam metal liner designs were tested and compared to the hardwall. Traditional Single-Degree-of-Freedom liner designs were also evaluated to provide a comparison. Normalized information on farfield acoustics is presented in this paper. The results show that up to 5 dB PWL overall attenuation was achieved in the forward quadrant. In general, the foam-metal liners performed better when the fan tip speed was below sonic.

  15. Potential use of lateritic and marine clay soils as landfill liners to retain heavy metals.

    PubMed

    Chalermyanont, Tanit; Arrykul, Surapon; Charoenthaisong, Nanthanit

    2009-01-01

    The potential of a lateritic soil and a marine clay, typical of those found in hot and humid climatic regions, was assessed for use as a landfill liner material. A series of tests were conducted - physical and chemical, batch adsorption, column, hydraulic conductivity, etc., - to evaluate the heavy metal sorption capacity, chemical compatibility of hydraulic conductivity, and transport parameters of the soils. Experimental results showed that the marine clay had better adsorption capacity than that of the lateritic soil and that its hydraulic conductivity was an order of magnitude lower. In addition, the hydraulic conductivities of both soils when permeated with low concentration heavy metal solutions were below 1x10(-7)cm/s. When permeated with Cr, Pb, Cd, Zn, and Ni solutions, the retardation factors of the lateritic soil and the marine clay ranged from 10 to 98 and 37 to 165, respectively, while the diffusion coefficients ranged from 1.0x10(-5) to 7.5x10(-6) and 3.0 to 9.14x10(-7)cm2/s, respectively. For both soils, Cr and Pb were retained relatively well, while Cd, Zn, and Ni were more mobile. The marine clay had higher retardation factors and lower diffusion coefficients, and its hydraulic conductivity was more compatible with Cr solution, than that of the lateritic soil. In general, the properties of the marine clay indicate that it has significant advantages over the lateritic soil as landfill liner material. PMID:18550353

  16. Enhanced highly charged ion production using a metal-dielectric liner in the KVI 14 GHz ECR ion source

    NASA Astrophysics Data System (ADS)

    Schachter, L.; Dobrescu, S.; Rodrigues, G.; Drentje, A. G.

    2002-02-01

    Forming on an aluminum surface a dielectric layer of alumina (aluminum oxide) in order to create a metal-dielectric (MD) structure increases the secondary-electron emission properties. The idea of using this material as a MD (Al-Al2O3) cylindrical liner inside an ECR ion source was previously tested in the 14 GHz ECRIS of IKF (Frankfurt/Main, Germany). The purpose of the present experiment was to observe the effect of such a MD liner on the high charge state operation of the KVI 14 GHz ECRIS, in particular in comparison to the technique of gas mixing. Measurements were made both with and without the MD liner, with pure argon and with an argon plus oxygen mixture. In the case of pure argon, the source with the MD liner is running remarkably stable. The high charge state ion beam currents are by far higher than those obtained in the situation where the source was operated with pure argon but without the MD liner. With MD liner, some low intensity oxygen peaks were clearly present in the spectra, implying that oxygen escaping or sputtered from the MD structure could give rise to an effect of "gas mixing." Therefore, the effect of mixing small amounts of oxygen into an argon plasma without the liner was studied in the same conditions of rf power and O3+ peak intensity. The conclusion was that the high charge state beam increase is not due to the oxygen gas mixing effect. The reason for the good performances of the source in the presence of the MD liner can be the increased density of cold electrons, but other effects could occur as well. This is subject of further studies.

  17. Conical shaped charge pressed powder, metal liner jet characterization and penetration in aluminum

    SciTech Connect

    Vigil, M.G.

    1997-05-01

    This work was conducted as part of a Near-wellbore Mechanics program at Sandia National Laboratories. An understanding of the interaction of the perforator jet from an explosive shaped charge with the fluid filled porous sandstone media is of basic importance to the completion of oil wells. Tests were conducted using the five-head Flash X-ray Test Site to measure the jet tip velocities and jet geometry for the OMNI and CAPSULE Conical Shaped Charge (CSC) oil well perforator jets fired into air. These tests were conducted to generate jet velocity and geometry information to be used in validating the CTH hydrocode modeling/simulation development of pressed powder, metal liner jets in air. Ten tests were conducted to determine the CSC jet penetration into 6061-T6 aluminum targets. Five tests were conducted with the OMNI CSC at 0.25, 6.0, and 19 inch standoffs from the target. Five tests were conducted with the CAPSULE CSC at 0.60, 5.0, 10.0, and 19 inch standoffs from the target. These tests were conducted to generate jet penetration into homogeneous target information for use in validating the CTH code modeling/simulation of pressed powder, metal liner jets penetrating aluminum targets. The Flash X-ray radiographs, jet velocities, jet diameters, and jet lengths data for jets fired into air are presented in this report. The jet penetration into aluminum and penetration hole profile data are also presented for the OMNI and CAPSULE perforators. Least Squares fits are presented for the measured jet velocity and jet penetration data.

  18. Experimental demonstration of the stabilizing effect of dielectric coatings on magnetically accelerated imploding metallic liners

    DOE PAGES

    Awe, Thomas James; Peterson, Kyle J.; Yu, Edmund P.; McBride, Ryan D.; Sinars, Daniel B.; Gomez, Matthew R.; Jennings, Christopher Ashley; Martin, Matthew R.; Rosenthal, Stephen E.; Sefkow, Adam B.; et al

    2016-02-10

    Enhanced implosion stability has been experimentally demonstrated for magnetically accelerated liners that are coated with 70 μm of dielectric. The dielectric tamps liner-mass redistribution from electrothermal instabilities and also buffers coupling of the drive magnetic field to the magneto-Rayleigh-Taylor instability. A dielectric-coated and axially premagnetized beryllium liner was radiographed at a convergence ratio [CR=Rin,0/Rin(z,t)] of 20, which is the highest CR ever directly observed for a strengthless magnetically driven liner. Lastly, the inner-wall radius Rin(z,t) displayed unprecedented uniformity, varying from 95 to 130 μm over the 4.0 mm axial height captured by the radiograph.

  19. Experimental Demonstration of the Stabilizing Effect of Dielectric Coatings on Magnetically Accelerated Imploding Metallic Liners.

    PubMed

    Awe, T J; Peterson, K J; Yu, E P; McBride, R D; Sinars, D B; Gomez, M R; Jennings, C A; Martin, M R; Rosenthal, S E; Schroen, D G; Sefkow, A B; Slutz, S A; Tomlinson, K; Vesey, R A

    2016-02-12

    Enhanced implosion stability has been experimentally demonstrated for magnetically accelerated liners that are coated with 70  μm of dielectric. The dielectric tamps liner-mass redistribution from electrothermal instabilities and also buffers coupling of the drive magnetic field to the magneto-Rayleigh-Taylor instability. A dielectric-coated and axially premagnetized beryllium liner was radiographed at a convergence ratio [CR=Rin,0/Rin(z,t)] of 20, which is the highest CR ever directly observed for a strengthless magnetically driven liner. The inner-wall radius Rin(z,t) displayed unprecedented uniformity, varying from 95 to 130  μm over the 4.0 mm axial height captured by the radiograph. PMID:26918996

  20. Outcomes of polyethylene liner cementation into a fixed metal acetabular shell with minimum follow-up of 7 years.

    PubMed

    Park, Myung-Sik; Yoon, Sun-Jung; Lee, Ju Rang

    2015-01-01

    Cementation of a polyethylene liner into the well-fixed shell is a convenient option for revision total hip arthroplasty. We retrospectively reviewed 45 patients who had liner cementation to investigate the risk factors which gave rise to major complications and reoperation. Patients were observed for a minimum of 7 years (range 7.8-14 years). Relevant risk factors (age, BMI, surgical approach, previous cup size and position, types of coated surface) were assessed with Cox regression analysis. The mean Harris Hip Score was improved from 62.5 (range 57-68) preoperatively to 87.1 (range 70-97). A total of 7 hips (15.5%) had acetabular component loosening that was treated with reoperation. Prevalence of acetabular component loosening was statistically significantly higher in hydroxyapatite-coated group (5 of 13) than in the Ti-coated group (2 of 32, p = 0.015). All recurrent dislocations occurred in patients treated with a posterior approach. Diameter of the previous metal shell of below 54 mm showed a lower 10-year survival rate than those greater than 54 mm in diameter. PE liner cementation in stable metal cup is a useful alternative option for carefully selected patients. Pre-existing HA-coated cups as well as small sized cups were indicative of poor outcomes.

  1. Study of the time-resolved, 3-dimensional current density distribution in solid metallic liners at 1 MA

    NASA Astrophysics Data System (ADS)

    Bott-Suzuki, S. C.; Cordaro, S. W.; Caballero Bendixsen, L. S.; Atoyan, L.; Byvank, T.; Potter, W.; Kusse, B. R.; Greenly, J. B.; Hammer, D. A.

    2016-09-01

    We present a study of the time varying current density distribution in solid metallic liner experiments at the 1 MA level. Measurements are taken using an array of magnetic field probes which provide 2D triangulation of the average centroid of the drive current in the load at 3 discrete axial positions. These data are correlated with gated optical self-emission imaging which directly images the breakdown and plasma formation region. Results show that the current density is azimuthally non-uniform and changes significantly throughout the 100 ns experimental timescale. Magnetic field probes show clearly motion of the current density around the liner azimuth over 10 ns timescales. If breakdown is initiated at one azimuthal location, the current density remains non-uniform even over large spatial extents throughout the current drive. The evolution timescales are suggestive of a resistive diffusion process or uneven current distributions among simultaneously formed but discrete plasma conduction paths.

  2. Thermal softening of metallic shaped-charge jets formed by the collapse of shaped-charge liners in the presence of a magnetic field

    NASA Astrophysics Data System (ADS)

    Fedorov, S. V.

    2016-05-01

    This paper presents an analysis of the possibility of increasing the ultimate stretching and penetration capability of metallic shaped-charge jets in the presence of an axial magnetic field in the shaped-charge liner due to heating and thermal softening of the jet material as a result of a sharp increase in the magnetic-field induction in the jet formation region upon liner collapse. This process is studied by numerical simulation in a quasi-two-dimensional formulation taking into account the inertial stretching of the conductive rigid-plastic rod in the presence of a longitudinal magnetic field in it.

  3. Acetabular liner fixation by cement.

    PubMed

    Jiranek, William A

    2003-12-01

    Many situations in revision THA require the exchange of a PE liner in the setting of a well-fixed cementless acetabular shell. Unfortunately, a replacement liner is not always available, the locking mechanism of the metal shell may be damaged or incompatible with the desired liner, or the shell is malpositioned. Revision of a well-fixed cementless acetabular shell has been associated with considerable morbidity. This raises several questions: can a new PE liner be fixed in the existing shell using bone cement, and if so, which techniques can improve the end result, and in which patients should they be used? Biomechanical testing of cemented PE liners has shown initial fixation strengths that exceed conventional locking mechanisms. It is not known during what period this initial fixation will fail, but clinical reports with followup of as many as 6 years have shown survival in approximately 90% of cases. These studies have shown the importance of proper patient selection, accurate sizing of the PE liner, careful preparation of the substrate of the liner and the shell, and good cement technique. The potential advantages of this technique are less surgical morbidity, more rapid surgery and patient recovery, the ability to incorporate antibiotics in the cement, and more liner options.

  4. Total Hip Arthroplasty Using Metal Head on a Highly Cross-linked Polyethylene Liner

    PubMed Central

    Kim, Min-Yook; Park, Ji-Hoon; Lee, Jung-Ho

    2015-01-01

    Purpose This retrospective study was performed to evaluate the clinical results and measure polyethylene liner wear in total hip arthroplasty (THA) with highly cross-linked polyethylene. Materials and Methods Except for patients who had died or were unable to have follow-up at least 2 years, 60 of 78 hips that underwent THA were included this study. The mean age was 64.5 years (range, 25-81 years) and the mean body mass index (BMI) was 23.0 kg/m2 (18.1-32.3 kg/m2). Diagnosis at the time of the operation was osteonecrois of the femoral head in 28 hips, primary osteoarthritis in 14, hip fracture in 13, and other diseases in 5. The mean follow-up period was 3.8 years (2.1-7.1 years). Harris hip score (HHS) was reviewed before THA and at the last follow-up. On the anteroposterior pelvic radiographs, acetabular cup inclination and ante-version were also measured. The annual linear wear rate was measured using Livermore's method on the radiographs. Results The mean HHS was 60.1 (28-94) before operation and 90.4 (47-100) at the last follow-up. In the immediate post-operation, the average inclination and anteversion angles of the acetabular cups were 46.3° (standard deviation, ±6.7°) and, 21.4°(±10.1°) respectively. The mean of the annual linear polyethylene wear was 0.079 mm/year (0.001-0.291 mm/year). Age, gender and BMI were not statistically related to linear polyethylene wear but the period of follow-up and the acetabular cup's inclination showed significant negative and positive correlation respectively. Conclusion The wear rate of a highly cross-linked polyethylene was shown to correlate negatively with duration of follow-up. However, our study was based on a short-term follow-up, so a long-term follow-up study is necessary in the future. PMID:27536629

  5. Synthesis, thermal and spectroscopic behaviors of metal-drug complexes: La(III), Ce(III), Sm(III) and Y(III) amoxicillin trihydrate antibiotic drug complexes

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.; Al-Maydama, Hussein M. A.; Al-Azab, Fathi M.; Amin, Ragab R.; Jamil, Yasmin M. S.

    2014-07-01

    The metal complexes of Amoxicillin trihydrate with La(III), Ce(III), Sm(III) and Y(III) are synthesized with 1:1 (metal:Amox) molar ratio. The suggested formula structures of the complexes are based on the results of the elemental analyses, molar conductivity, (infrared, UV-visible and fluorescence) spectra, effective magnetic moment in Bohr magnetons, as well as the thermal analysis (TG), and characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The results obtained suggested that Amoxicillin reacted with metal ions as tridentate ligands, coordinating the metal ion through its amino, imino, and β-lactamic carbonyl. The kinetic thermodynamic parameters such as: Ea, ΔH*, ΔS* and ΔG* were estimated from the DTG curves.

  6. Synthesis, thermal and spectroscopic behaviors of metal-drug complexes: La(III), Ce(III), Sm(III) and Y(III) amoxicillin trihydrate antibiotic drug complexes.

    PubMed

    Refat, Moamen S; Al-Maydama, Hussein M A; Al-Azab, Fathi M; Amin, Ragab R; Jamil, Yasmin M S

    2014-07-15

    The metal complexes of Amoxicillin trihydrate with La(III), Ce(III), Sm(III) and Y(III) are synthesized with 1:1 (metal:Amox) molar ratio. The suggested formula structures of the complexes are based on the results of the elemental analyses, molar conductivity, (infrared, UV-visible and fluorescence) spectra, effective magnetic moment in Bohr magnetons, as well as the thermal analysis (TG), and characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The results obtained suggested that Amoxicillin reacted with metal ions as tridentate ligands, coordinating the metal ion through its amino, imino, and β-lactamic carbonyl. The kinetic thermodynamic parameters such as: Ea, ΔH(*), ΔS(*) and ΔG(*) were estimated from the DTG curves.

  7. Evaluating the Acoustic Effect of Over-the-Rotor Foam-Metal Liner Installed on a Low Speed Fan Using Virtual Rotating Microphone Imaging

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; Dougherty, Robert P.; Walker, Bruce E.

    2010-01-01

    An in-duct beamforming technique for imaging rotating broadband fan sources has been used to evaluate the acoustic characteristics of a Foam-Metal Liner installed over-the-rotor of a low-speed fan. The NASA Glenn Research Center s Advanced Noise Control Fan was used as a test bed. A duct wall-mounted phased array consisting of several rings of microphones was employed. The data are mathematically resampled in the fan rotating reference frame and subsequently used in a conventional beamforming technique. The steering vectors for the beamforming technique are derived from annular duct modes, so that effects of reflections from the duct walls are reduced.

  8. Synthesis and in vitro microbial evaluation of La(III), Ce(III), Sm(III) and Y(III) metal complexes of vitamin B6 drug.

    PubMed

    Refat, Moamen S; Al-Azab, Fathi M; Al-Maydama, Hussein M A; Amin, Ragab R; Jamil, Yasmin M S

    2014-06-01

    Metal complexes of pyridoxine mono hydrochloride (vitamin B6) are prepared using La(III), Ce(III), Sm(III) and Y(III). The resulting complexes are investigated. Some physical properties, conductivity, analytical data and the composition of the four pyridoxine complexes are discussed. The elemental analysis shows that the formed complexes of La(III), Ce(III), Sm(III) and Y(III) with pyridoxine are of 1:2 (metal:PN) molar ratio. All the synthesized complexes are brown in color and possess high melting points. These complexes are partially soluble in hot methanol, dimethylsulfoxide and dimethylformamide and insoluble in water and some other organic solvents. Elemental analysis data, spectroscopic (IR, UV-vis. and florescence), effective magnetic moment in Bohr magnetons and the proton NMR suggest the structures. However, definite particle size is determined by invoking the X-ray powder diffraction and scanning electron microscopy data. The results obtained suggested that pyridoxine reacted with metal ions as a bidentate ligand through its phenolate oxygen and the oxygen of the adjacent group at the 4'-position. The molar conductance measurements proved that the pyridoxine complexes are electrolytic in nature. The kinetic and thermodynamic parameters such as: Ea, ΔH(*), ΔS(*) and ΔG(*) were estimated from the DTG curves. The antibacterial evaluation of the pyridoxine and their complexes were also performed against some gram positive, negative bacteria as well as fungi.

  9. Synthesis and in vitro microbial evaluation of La(III), Ce(III), Sm(III) and Y(III) metal complexes of vitamin B6 drug

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.; Al-Azab, Fathi M.; Al-Maydama, Hussein M. A.; Amin, Ragab R.; Jamil, Yasmin M. S.

    2014-06-01

    Metal complexes of pyridoxine mono hydrochloride (vitamin B6) are prepared using La(III), Ce(III), Sm(III) and Y(III). The resulting complexes are investigated. Some physical properties, conductivity, analytical data and the composition of the four pyridoxine complexes are discussed. The elemental analysis shows that the formed complexes of La(III), Ce(III), Sm(III) and Y(III) with pyridoxine are of 1:2 (metal:PN) molar ratio. All the synthesized complexes are brown in color and possess high melting points. These complexes are partially soluble in hot methanol, dimethylsulfoxide and dimethylformamide and insoluble in water and some other organic solvents. Elemental analysis data, spectroscopic (IR, UV-vis. and florescence), effective magnetic moment in Bohr magnetons and the proton NMR suggest the structures. However, definite particle size is determined by invoking the X-ray powder diffraction and scanning electron microscopy data. The results obtained suggested that pyridoxine reacted with metal ions as a bidentate ligand through its phenolate oxygen and the oxygen of the adjacent group at the 4‧-position. The molar conductance measurements proved that the pyridoxine complexes are electrolytic in nature. The kinetic and thermodynamic parameters such as: Ea, ΔH*, ΔS* and ΔG* were estimated from the DTG curves. The antibacterial evaluation of the pyridoxine and their complexes were also performed against some gram positive, negative bacteria as well as fungi.

  10. Prediction of heavy metal removal by different liner materials from landfill leachate: modeling of experimental results using artificial intelligence technique.

    PubMed

    Turan, Nurdan Gamze; Gümüşel, Emine Beril; Ozgonenel, Okan

    2013-01-01

    An intensive study has been made to see the performance of the different liner materials with bentonite on the removal efficiency of Cu(II) and Zn(II) from industrial leachate. An artificial neural network (ANN) was used to display the significant levels of the analyzed liner materials on the removal efficiency. The statistical analysis proves that the effect of natural zeolite was significant by a cubic spline model with a 99.93% removal efficiency. Optimization of liner materials was achieved by minimizing bentonite mixtures, which were costly, and maximizing Cu(II) and Zn(II) removal efficiency. The removal efficiencies were calculated as 45.07% and 48.19% for Cu(II) and Zn(II), respectively, when only bentonite was used as liner material. However, 60% of natural zeolite with 40% of bentonite combination was found to be the best for Cu(II) removal (95%), and 80% of vermiculite and pumice with 20% of bentonite combination was found to be the best for Zn(II) removal (61.24% and 65.09%). Similarly, 60% of natural zeolite with 40% of bentonite combination was found to be the best for Zn(II) removal (89.19%), and 80% of vermiculite and pumice with 20% of bentonite combination was found to be the best for Zn(II) removal (82.76% and 74.89%). PMID:23844384

  11. Prediction of Heavy Metal Removal by Different Liner Materials from Landfill Leachate: Modeling of Experimental Results Using Artificial Intelligence Technique

    PubMed Central

    Turan, Nurdan Gamze; Gümüşel, Emine Beril; Ozgonenel, Okan

    2013-01-01

    An intensive study has been made to see the performance of the different liner materials with bentonite on the removal efficiency of Cu(II) and Zn(II) from industrial leachate. An artificial neural network (ANN) was used to display the significant levels of the analyzed liner materials on the removal efficiency. The statistical analysis proves that the effect of natural zeolite was significant by a cubic spline model with a 99.93% removal efficiency. Optimization of liner materials was achieved by minimizing bentonite mixtures, which were costly, and maximizing Cu(II) and Zn(II) removal efficiency. The removal efficiencies were calculated as 45.07% and 48.19% for Cu(II) and Zn(II), respectively, when only bentonite was used as liner material. However, 60% of natural zeolite with 40% of bentonite combination was found to be the best for Cu(II) removal (95%), and 80% of vermiculite and pumice with 20% of bentonite combination was found to be the best for Zn(II) removal (61.24% and 65.09%). Similarly, 60% of natural zeolite with 40% of bentonite combination was found to be the best for Zn(II) removal (89.19%), and 80% of vermiculite and pumice with 20% of bentonite combination was found to be the best for Zn(II) removal (82.76% and 74.89%). PMID:23844384

  12. Electrochemistry and spectroscopy of ortho-metalated complexes of Ir(III) and Rh(III)

    SciTech Connect

    Ohsawa, Y.; Sprouse, S.; King, K.A.; DeArmond, M.K.; Hanck, K.W.; Watts, R.J.

    1987-02-26

    The electrochemical and UV-visible spectroscopic properties of Rh(III) and Ir(III) complexes of the ortho-metalating (NC) ligands, 2-phenylpyridine (ppy) and benzo(h)quinone (bzq), have been studied. Cyclic voltammetric studies of several of the dimeric species, (M(NC)/sub 2/Cl)/sub 2/, indicate metal-centered oxidation occurs at moderate potentials. Cationic monomers of the type M(NC)/sub 2/(NN)/sup +/ where (NN) = 2,2'-bipyridine or 1,10-phenanthroline have been prepared by reaction of the chelating ligands with the parent dimers. Cyclic voltammetric studies of these monomers indicate that several reversible ligand-centered reductions are generally observed and that the chelating ligand is more easily reduced than is the ortho-metalating ligand. Spectroscopic studies of the mixed ligand monomers indicate that dual emissions from MLCT states associated with the ortho-metalating and chelating ligands occur in the Ir(III) complexes whereas a single emission from a ligand-localized excited state is observed in the Rh(III) complexes. These results are discussed in terms of electronic and nuclear coupling factors analogous to those encountered in descriptions of bimolecular energy and electron-transfer processes.

  13. Ramp compression of a metallic liner driven by a shaped 5 MA current on the SPHINX machine

    NASA Astrophysics Data System (ADS)

    d'Almeida, T.; Lassalle, F.; Morell, A.; Grunenwald, J.; Zucchini, F.; Loyen, A.; Maysonnave, T.; Chuvatin, A.

    2014-05-01

    SPHINX is a 6MA, 1-us Linear Transformer Driver operated by the CEA Gramat (France) and primarily used for imploding Z-pinch loads for radiation effects studies. A method for performing magnetic ramp compression experiments was developed using a compact Dynamic Load Current Multiplier inserted between the convolute and the load, to shape the initial current pulse. We present the overall experimental configuration chosen for these experiments and initial results obtained over a set of experiments on an aluminum cylindrical liner. Current profiles measured at various critical locations across the system, are in good agreement with simulated current profiles. The liner inner free surface velocity measurements agree with the hydrocode results obtained using the measured load current as the input. The potential of the technique in terms of applications and achievable ramp pressure levels lies in the prospects for improving the DLCM efficiency.

  14. Ramp compression of a metallic liner driven by a shaped 5 MA current on the SPHINX machine

    NASA Astrophysics Data System (ADS)

    D'Almeida, Thierry; Lassalle, Francis; Morell, Alain; Grunenwald, Julien; Zucchini, Frédéric; Loyen, Arnaud; Maysonnave, Thomas; Chuvatin, Alexandre

    2013-06-01

    SPHINX is a 6MA, 1- μs Linear Transformer Driver operated by the CEA Gramat (France) and primarily used for imploding Z-pinch loads for radiation effects studies. Among the options that are currently being considered for improving the generator performances, there is a compact Dynamic Load Current Amplifier (DLCM). A method for performing magnetic ramp compression experiments, without modifying the generator operation scheme, was developed using the DLCM to shape the initial current pulse. We present the overall experimental configuration chosen for these experiments, based on electrical and hydrodynamic simulations. Initial results obtained over a set of experiments on an aluminum cylindrical liner, ramp-compressed to a peak pressure of 23 GPa, are presented. Details of the electrical and Photonic Doppler Velocimetry (PDV) setups used to monitor and diagnose the ramp compression experiments are provided. Current profiles measured at various locations across the system, particularly the load current, agree with simulated current profile and demonstrate adequate pulse shaping by the DLCM. The liner inner free surface velocity measurements agree with the hydrocode results obtained using the measured load current as the input. Higher ramp pressure levels are foreseen in future experiments with an improved DLCM system.

  15. Interaction of ribonucleotides with metal hexacyanocobaltate(III): a possible role in chemical evolution.

    PubMed

    Ali, Shah Raj; Kamaluddin

    2007-06-01

    It has been proposed that metal cyanide complexes would have acted as effective prebiotic catalysts. Insoluble metal cyanide complexes could have concentrated biomonomers from the dilute prebiotic soup, facilitating certain prebiotic reactions. In the light of the above hypothesis, interaction of four ribonucleotides, namely 5'-AMP, 5'-GMP, 5'-CMP, and 5'-UMP with copper(II)- and cadmium(II) hexacyanocobaltate(III) has been studied. The interaction was found to be maximum at neutral pH. 5'-GMP showed greater interaction with both the metal hexacyanocobaltate(III) while copper(II) hexacyanocobaltate(III) showed greater uptake than cadmium(II) hexacyanocobaltate(III) for all the four ribonucleotides studied. Infrared spectral studies of ribonucleotides, metal hexacyanocobaltate(III) and ribonucleotide - metal hexacyanocobaltate(III) adducts indicated that the nitrogen base and phosphate moiety of ribonucleotides interact with outer divalent metal ion present in the lattice of metal hexacyanocobaltate(III).

  16. Acoustic Liner for Turbomachinery Applications

    NASA Technical Reports Server (NTRS)

    Huff, Dennis L.; Sutliff, Daniel L.; Jones, Michael G.; Hebsur, Mohan G.

    2010-01-01

    The purpose of this innovation is to reduce aircraft noise in the communities surrounding airports by significantly attenuating the noise generated by the turbomachinery, and enhancing safety by providing a containment barrier for a blade failure. Acoustic liners are used in today's turbofan engines to reduce noise. The amount of noise reduction from an acoustic liner is a function of the treatment area, the liner design, and the material properties, and limited by the constraints of the nacelle or casement design. It is desirable to increase the effective area of the acoustic treatment to increase noise suppression. Modern turbofan engines use wide-chord rotor blades, which means there is considerable treatment area available over the rotor tip. Turbofan engines require containment over the rotors for protection from blade failure. Traditional methods use a material wrap such as Kevlar integrated with rub strips and sometimes metal layers (sandwiches). It is possible to substitute the soft rub-strip material with an open-cell metallic foam that provides noise-reduction benefits and a sacrificial material in the first layer of the containment system. An open-cell foam was evaluated that behaves like a bulk acoustic liner, serves as a tip rub strip, and can be integrated with a rotor containment system. Foams can be integrated with the fan-containment system to provide sufficient safety margins and increased noise attenuation. The major innovation is the integration of the foam with the containment.

  17. Voluntary Consensus Organization Standards for Nondestructive Evaluation of Thin-Walled Metallic Liners and Composite Overwraps in Composite Overwrapped Pressure Vessels

    NASA Technical Reports Server (NTRS)

    Waller, Jess; Saulsberry, Regor

    2012-01-01

    NASA fracture control requirements outlined in NASA-STD-5009 and NASA-STD-5014 are predicated on the availability and use of sensitive nondestructive evaluation (NDE) methods that can detect and monitor defects, thereby providing data that can be used to predict failure or reduce the risk of failure in fracture critical components. However, in the case of composite materials and components, including composite overwrapped pressure vessels (COPVs), the effect of defects is poorly understood, the NDE methods used to evaluate locate and size defects are typically at lower technical readiness level than analogous NDE methods used for metals, and demonstration studies to verify the probability of detection (POD) are generally lacking or unavailable. These factors together make failure prediction of fracture critical composite materials and components based on size, quantity, or orientation of defects nearly impossible. Also, when inspecting metal liners in as-manufactured COPVs, sensitivity is lost and only the inner surface of the liner is accessible. Also, NDE of COPVs as applied during manufacturing varies significantly from manufacturer to manufacturer and has not yet been standardized. Although requirements exist to perform NDE immediately after manufacturing to establish initial integrity of the parts, procedural detail for NDE of composites is still nonexistent or under development. For example, in practice, only a visual inspection of COPVs is performed during manufacturing and service, leaving in question whether defects of concern, for example, bridging, overwrap winding anomalies, impact damage below visible threshold, out-of-family strain growth, and liner buckling have been adequately detected and monitored. To address these shortcomings, in 2005 the NASA Nondestructive Evaluation Working Group (NNWG) began funding work to develop and adopt standards for nondestructive evaluation of aerospace composites in collaboration with the American Society for Testing

  18. Synthesis of Imine-Naphthol Tripodal Ligand and Study of Its Coordination Behaviour towards Fe(III), Al(III), and Cr(III) Metal Ions

    PubMed Central

    Kaur, Kirandeep

    2014-01-01

    A hexadentate Schiff base tripodal ligand is synthesized by the condensation of tris (2-aminoethyl) amine with 2-hydroxy-1-naphthaldehyde and characterized by various spectroscopic techniques like UV-VIS, IR, NMR, MASS, and elemental analysis. The solution studies by potentiometric and spectrophotometric methods are done at 25 ± 1°C, µ = 0.1 M KCl, to calculate the protonation constants of the ligand and formation constants of metal complexes formed by the ligand with Fe(III), Al(III), and Cr(III) metal ions. The affinity of the ligand towards Fe(III) is compared with deferiprone (a drug applied for iron intoxication) and transferrin (the main Fe(III) binding protein in plasma). Structural analysis of the ligand and the metal complexes was done using semiempirical PM6 method. Electronic and IR spectra are calculated by semiempirical methods and compared with experimental one. PMID:25294978

  19. Synthesis of Imine-Naphthol Tripodal Ligand and Study of Its Coordination Behaviour towards Fe(III), Al(III), and Cr(III) Metal Ions.

    PubMed

    Kaur, Kirandeep; Baral, Minati

    2014-01-01

    A hexadentate Schiff base tripodal ligand is synthesized by the condensation of tris (2-aminoethyl) amine with 2-hydroxy-1-naphthaldehyde and characterized by various spectroscopic techniques like UV-VIS, IR, NMR, MASS, and elemental analysis. The solution studies by potentiometric and spectrophotometric methods are done at 25 ± 1°C, µ = 0.1 M KCl, to calculate the protonation constants of the ligand and formation constants of metal complexes formed by the ligand with Fe(III), Al(III), and Cr(III) metal ions. The affinity of the ligand towards Fe(III) is compared with deferiprone (a drug applied for iron intoxication) and transferrin (the main Fe(III) binding protein in plasma). Structural analysis of the ligand and the metal complexes was done using semiempirical PM6 method. Electronic and IR spectra are calculated by semiempirical methods and compared with experimental one. PMID:25294978

  20. Synthesis of Imine-Naphthol Tripodal Ligand and Study of Its Coordination Behaviour towards Fe(III), Al(III), and Cr(III) Metal Ions.

    PubMed

    Kaur, Kirandeep; Baral, Minati

    2014-01-01

    A hexadentate Schiff base tripodal ligand is synthesized by the condensation of tris (2-aminoethyl) amine with 2-hydroxy-1-naphthaldehyde and characterized by various spectroscopic techniques like UV-VIS, IR, NMR, MASS, and elemental analysis. The solution studies by potentiometric and spectrophotometric methods are done at 25 ± 1°C, µ = 0.1 M KCl, to calculate the protonation constants of the ligand and formation constants of metal complexes formed by the ligand with Fe(III), Al(III), and Cr(III) metal ions. The affinity of the ligand towards Fe(III) is compared with deferiprone (a drug applied for iron intoxication) and transferrin (the main Fe(III) binding protein in plasma). Structural analysis of the ligand and the metal complexes was done using semiempirical PM6 method. Electronic and IR spectra are calculated by semiempirical methods and compared with experimental one.

  1. Liner environment effects study

    NASA Technical Reports Server (NTRS)

    Venkataramani, K. S.; Ekstedt, E. E.

    1984-01-01

    The Liner Environment Effects Study Program is aimed at establishing a broad heat transfer data base under controlled experimental conditions by quantifying the effects of the combustion system conditions on the combustor liner thermal loading and on the flame radiation characteristics. Five liner concepts spanning the spectrum of liner design technology from the very simple to the most advanced concepts are investigated. These concepts comprise an uncooled liner, a conventional film cooled liner, an impingement/film cooled liner, a laser drilled liner approaching the concept of a porous wall, and a siliconized silicon carbide ceramic liner. Effect of fuel type is covered by using fuels containing 11.8, 12.8, and 14% hydrogen. Tests at 100, 200, and 300 psia provide a basis for evaluating the effect of pressure on the heat transfer. The effects of the atomization quality and spray characteristics are examined by varying the fuel spray Sauter mean diameter and the spray angle. Additional varied parameters include reference velocity, a wide range of equivalence ratio, cooling flow rate, coolant temperature and the velocity of the coolant stream on the backside of the liner.

  2. Probing the Physics of Narrow-line Regions in Active Galaxies. III. Accretion and Cocoon Shocks in the LINER NGC 1052

    NASA Astrophysics Data System (ADS)

    Dopita, Michael A.; Ho, I.-Ting; Dressel, Linda L.; Sutherland, Ralph; Kewley, Lisa; Davies, Rebecca; Hampton, Elise; Shastri, Prajval; Kharb, Preeti; Jose, Jessy; Bhatt, Harish; Ramya, S.; Scharwächter, Julia; Jin, Chichuan; Banfield, Julie; Zaw, Ingyin; James, Bethan; Juneau, Stéphanie; Srivastava, Shweta

    2015-03-01

    We present Wide Field Spectrograph integral field spectroscopy and Hubble Space Telescope Faint Object Spectrograph spectroscopy for the low-ionization nuclear emission line region (LINER) galaxy NGC 1052. We infer the presence of a turbulent accretion flow forming a small-scale accretion disk. We find a large-scale outflow and ionization cone along the minor axis of the galaxy. Part of this outflow region is photoionized by the active galactic nucleus and shares properties with the extended narrow-line region of Seyfert galaxies, but the inner (R≲ 1.0″) accretion disk and the region around the radio jet appear shock excited. The emission-line properties can be modeled by a “double-shock” model in which the accretion flow first passes through an accretion shock in the presence of a hard X-ray radiation, and the accretion disk is then processed through a cocoon shock driven by the overpressure of the radio jets. This model explains the observation of two distinct densities (˜104 and ˜106 cm-3) and provides a good fit to the observed emission-line spectrum. We derive estimates for the velocities of the two shock components and their mixing fractions, the black hole mass, and the accretion rate needed to sustain the LINER emission and derive an estimate for the jet power. Our emission-line model is remarkably robust against variation of input parameters and hence offers a generic explanation for the excitation of LINER galaxies, including those of spiral type such as NGC 3031 (M81).

  3. Thin-metal lined PRD 49-III composite vessels. [evaluation of pressure vessels for burst strength and fatigue performance

    NASA Technical Reports Server (NTRS)

    Hoggatt, J. T.

    1974-01-01

    Filament wound pressure vessels of various configurations were evaluated for burst strength and fatigue performance. The dimensions and characteristics of the vessels are described. The types of tests conducted are explained. It was determined that all vessels leaked in a relatively few cycles (20 to 60 cycles) with failure occurring in all cases in the metallic liner. The thin liner would de-bond from the composite and buckling took place during depressurization. No composite failures or indications of impeding composite failures were obtained in the metal-lined vessels.

  4. Liner mounting assembly

    NASA Technical Reports Server (NTRS)

    Halila, Ely E. (Inventor)

    1994-01-01

    A mounting assembly includes an annular supporting flange disposed coaxially about a centerline axis which has a plurality of circumferentially spaced apart supporting holes therethrough. An annular liner is disposed coaxially with the supporting flange and includes a plurality of circumferentially spaced apart mounting holes aligned with respective ones of the supporting holes. Each of a plurality of mounting pins includes a proximal end fixedly joined to the supporting flange through a respective one of the supporting holes, and a distal end disposed through a respective one of the liner mounting holes for supporting the liner to the supporting flange while unrestrained differential thermal movement of the liner relative to the supporting flange.

  5. Photophysical properties of ortho-metalated monomeric and dimeric complexes containing rhodium(III) and iridium(III) metal centers

    NASA Astrophysics Data System (ADS)

    Marshall, Jason Alexander

    Photophysical properties of dichloro-bridged dimers and monomeric tris complexes of the type [M(NC)2Cl]2 and M(NC)3, where NC refers to the ortho-metalating ligands 2-phenylpyridine (ppy), benzo[h]quinoline (bzq), or 2-(p-tolyl)pyridine (ptpy) and M is Rh(III) or Ir(III), were investigated. Excited-state emission of Rh(III) complexes are highly structured and independent of temperature from 4--100 K in glassy media, with long lifetimes (102 mus to ms). Emission is not observed from the pale yellow, fluid solutions of Rh(III) complexes at room temperature. Below 7K, decay kinetics are sensitive to temperature and are complicated, requiring multi-exponential fits in 4:1 EtOH/MeOH. The spectroscopic properties are consistent with the assignment of a lowest 3pipi* excited-state manifold perturbed by an admixture of higher-lying states possessing strong spin-orbit interactions. The complicated decays are attributed to spin-relaxation-limited behavior between spin-levels in the 3pipi* manifold. Deep yellow solutions of Ir(III) complexes in 4:1 EtOH/MeOH are observed to emit in both glassy media and in fluid solution, displaying severe changes in spectral shape as the glass softens which are not attributable to rigidochromic shifts. Low-temperature spectra are structured with emission origins in the range 496--520 nm whereas room-temperature emission of complexes in fluid solution are characteristically broad structureless bands with maxima redshifted from spectra measured in rigid media. Both the emission and the excited-state lifetimes display temperature dependence, with lifetimes in the microsecond to tens of microseconds range at 77 K, increasing by more than an order of magnitude as the temperature is decreased to 4 K. Each of these characteristic band shapes arises from separate components of the emission which have been time-resolved from the low-temperature spectrum. A long-lived, structured component of the emission, only observed in rigid media, has been

  6. Development of 1D Liner Compression Code for IDL

    NASA Astrophysics Data System (ADS)

    Shimazu, Akihisa; Slough, John; Pancotti, Anthony

    2015-11-01

    A 1D liner compression code is developed to model liner implosion dynamics in the Inductively Driven Liner Experiment (IDL) where FRC plasmoid is compressed via inductively-driven metal liners. The driver circuit, magnetic field, joule heating, and liner dynamics calculations are performed at each time step in sequence to couple these effects in the code. To obtain more realistic magnetic field results for a given drive coil geometry, 2D and 3D effects are incorporated into the 1D field calculation through use of correction factor table lookup approach. Commercial low-frequency electromagnetic fields solver, ANSYS Maxwell 3D, is used to solve the magnetic field profile for static liner condition at various liner radius in order to derive correction factors for the 1D field calculation in the code. The liner dynamics results from the code is verified to be in good agreement with the results from commercial explicit dynamics solver, ANSYS Explicit Dynamics, and previous liner experiment. The developed code is used to optimize the capacitor bank and driver coil design for better energy transfer and coupling. FRC gain calculations are also performed using the liner compression data from the code for the conceptual design of the reactor sized system for fusion energy gains.

  7. Stability of Magnetically Implode Liners for High Energy Density Experiments

    SciTech Connect

    Reinovsky, R.E.; Anderson, W.E.; Atchison, W.L.; Bartsch, R.R.; Clark, D.A.; Ekdahl, C.E.; Faehl, R.J.; Goforth, J.H.; Keinigs, R.K.; Lindemuth, I.R.; Morgan, D.; Rodriguez, G.; Tasker, D.G.; Trainor, R.J.; Shlachter, J.S.

    1998-10-18

    Magnetically imploded cylindrical metal shells (z-pinch liners) are attractive drivers for a wide variety of hydrodynamics and material properties experiments. The ultimate utility of liners depends on the acceleration of near-solid density shells to velocities exceeding 20 km/sec with good azimuthal symmetry and axial uniformity. Two pulse power systems (Ranchero and Atlas) currently operational or under development at Los Alamos provide electrical energy adequate to accelerate {approximately}50 gr. liners to 1-2 MJ/cm kinetic energy. As in all z-pinches, the outer surface of a magnetically imploded liner is unstable to magneto-Rayleigh-Taylor (RT) modes during acceleration. Large-scale distortion in the liners from RT modes growing from glide plane interactions or initial imperfections could make liners unusable for man experiments. On the other hand, material strength in the liner should, from first principles, reduce the growth rate of RT modes - and can render some combinations of wavelength and amplitude analytically stable. The growth of instabilities in both soft aluminum liners and in high strength aluminum alloy liners has been studied analytically, computationally and experimentally at liner kinetic energies up to 100 KJ/cm on the Pegasus capacitor bank using driving currents up to 12 MA.

  8. Use of natural zeolites as a landfill liner.

    PubMed

    Tuncan, Ahmet; Tuncan, Mustafa; Koyuncu, Hakan; Guney, Yucel

    2003-02-01

    The purpose of this study is to investigate certain features of a novel material proposed to serve as an impervious liner in landfills. Various ratios of bentonites and zeolites (B/Z) compacted at optimum water content were tested to determine the strength parameters, permeability, pH, heavy metals and other properties. A B/Z ratio of 0.10 was found to be an ideal landfill liner material regarding its low hydraulic conductivity and high cation exchange capacity. The use of B/Z mixtures as an alternative to clay liners would provide potential to significantly reduce the thickness of base liner for landfills.

  9. Combustor liner cooling system

    DOEpatents

    Lacy, Benjamin Paul; Berkman, Mert Enis

    2013-08-06

    A combustor liner is disclosed. The combustor liner includes an upstream portion, a downstream end portion extending from the upstream portion along a generally longitudinal axis, and a cover layer associated with an inner surface of the downstream end portion. The downstream end portion includes the inner surface and an outer surface, the inner surface defining a plurality of microchannels. The downstream end portion further defines a plurality of passages extending between the inner surface and the outer surface. The plurality of microchannels are fluidly connected to the plurality of passages, and are configured to flow a cooling medium therethrough, cooling the combustor liner.

  10. Photophysical effects of metal-carbon sigma bonds in ortho-metalated complexes of Ir(III) and Rh(III)

    SciTech Connect

    Sprouse, S.; King, K.A.; Spellane, P.J.; Watts, R.J.

    1984-10-31

    Dichloro-bridged dimers of the type (M(L)/sub 2/Cl)/sub 2/, where L is 2-phenylpyridine (ppy) or benzo(h)quinoline (bzq) and M is Rh(III) or Ir(III), have been characterized by /sup 13/C and /sup 1/H NMR spectroscopies and by absorption and emission spectroscopies. The NMR results confirm previous formulations of the complexes as dichloro-bridged ortho-metalated dimers in halocarbon solvents but indicate that they are cleaved to monomeric species of the type M(L)/sub 2/CIS in ligating solvents such as dimethylformamide (S = solvent). The absorption spectra of each of the complexes contain several low-energy bands which are assigned as metal-to-ligand charge-transfer (MLCT) transitions. All four of the dimers emit light following photoexcitation of their glassy solutions at 77 K. Their emission spectra and lifetimes lead to assignments of their emitting states as intraligand for the Rh(III) dimers and MLCT for the Ir(III) dimers. The Ir(III) dimers are also found to emit light following excitation at 295 K in deaerated dichloromethane. No emission is seen from the Rh(III) dimers under these conditions. Comparison of these results with previous results from studies of similar Rh(III) and Ir(III) complexes of 2,2'-bipyridine (bpy) and 1,10-phenanthroline (phen) indicates that the ortho-metalated ligands are considerably higher than bpy and phen in the spectrochemical series. In addition to raising the energy of ligand field excited states in their complexes, relative to similar bpy and phen species, they induce lower energy charge-transfer transitions. These effects are consistent with the synergistic function of the ortho-metalated ligands as both strong sigma donors and ..pi.. acceptors.

  11. Combustor liner durability analysis

    NASA Technical Reports Server (NTRS)

    Moreno, V.

    1981-01-01

    An 18 month combustor liner durability analysis program was conducted to evaluate the use of advanced three dimensional transient heat transfer and nonlinear stress-strain analyses for modeling the cyclic thermomechanical response of a simulated combustor liner specimen. Cyclic life prediction technology for creep/fatigue interaction is evaluated for a variety of state-of-the-art tools for crack initiation and propagation. The sensitivity of the initiation models to a change in the operating conditions is also assessed.

  12. Performance of semi-transportation-cooled liner in high-temperature-rise combustors

    NASA Technical Reports Server (NTRS)

    Wear, J. D.; Trout, A. M.; Smith, J. M.

    1981-01-01

    Results from tests with the Lamilloy combustor liner are compared with results obtained from a conventionally designed, film cooled, step-louver liner. Operation of the Lamilloy liner with counterrotating swirl combustor fuel modules with mixing venturis was possible to a fuel-air ratio of 0.065 without obtaining excessive liner metal temperatures. At the 0.065 fuel-air condition the average liner metal temperature was 140 K and the maximum local temperature 280 K above the inlet air temperature. Combustion efficiency, pattern factor, and smoke data are discussed.

  13. Attenuation of landfill leachate by clay liner materials in laboratory columns: 2. Behaviour of inorganic contaminants.

    PubMed

    Thornton, S F; Lerner, D N; Tellam, J H

    2001-02-01

    The chemical attenuation of inorganic contaminants in methanogenic landfill leachate, spiked with heavy metals (Cd, Cd, Ni and Zn), by two UK clay liner materials was compared in laboratory columns over 15 months. Ammonium was attenuated by ion-exchange but this attenuation was finite and when exhausted, NH4 passed through the liners at concentrations found in the leachate. The breakthrough behaviour of NH4 could be described by a simple distribution coefficient. Heavy metals were attenuated by sorption and precipitation of metal sulphide and carbonate compounds near the top of the liner. Adequate SO4 and CaCO3 in the liner is necessary to ensure the long term retention of heavy metals, and pH buffering agents added to stabilise reactive metal fractions should be admixed with the liner. Some metals may not be chemically attenuated by clay liners due to the formation of stable complexes with organic and/or colloidal fractions in leachate. Flushing of the liners with oxygenated water after leachate caused mobilisation of attenuated contaminants. Sorbed NH4 was released by the liners but groundwater loadings were manageable. Re-oxidation of metal sulphides under these conditions resulted in the release of heavy metals from the liners when the pH buffering capacity was poor. Contaminant attenuation by the clay liners was similar and the attenuation of NH4 and heavy metals could be predicted from the geochemical properties of the liner using simple tests. A conceptual model of clay liner performance is presented. Chemical attenuation of inorganic pollutants can be included in containment liner design to produce a dual reactive-passive barrier for landfills.

  14. Attenuation of landfill leachate by clay liner materials in laboratory columns: 2. Behaviour of inorganic contaminants.

    PubMed

    Thornton, S F; Lerner, D N; Tellam, J H

    2001-02-01

    The chemical attenuation of inorganic contaminants in methanogenic landfill leachate, spiked with heavy metals (Cd, Cd, Ni and Zn), by two UK clay liner materials was compared in laboratory columns over 15 months. Ammonium was attenuated by ion-exchange but this attenuation was finite and when exhausted, NH4 passed through the liners at concentrations found in the leachate. The breakthrough behaviour of NH4 could be described by a simple distribution coefficient. Heavy metals were attenuated by sorption and precipitation of metal sulphide and carbonate compounds near the top of the liner. Adequate SO4 and CaCO3 in the liner is necessary to ensure the long term retention of heavy metals, and pH buffering agents added to stabilise reactive metal fractions should be admixed with the liner. Some metals may not be chemically attenuated by clay liners due to the formation of stable complexes with organic and/or colloidal fractions in leachate. Flushing of the liners with oxygenated water after leachate caused mobilisation of attenuated contaminants. Sorbed NH4 was released by the liners but groundwater loadings were manageable. Re-oxidation of metal sulphides under these conditions resulted in the release of heavy metals from the liners when the pH buffering capacity was poor. Contaminant attenuation by the clay liners was similar and the attenuation of NH4 and heavy metals could be predicted from the geochemical properties of the liner using simple tests. A conceptual model of clay liner performance is presented. Chemical attenuation of inorganic pollutants can be included in containment liner design to produce a dual reactive-passive barrier for landfills. PMID:11525477

  15. MiniBooNE liner integrity study

    SciTech Connect

    Ray Stefanski, Phil Martin and Jeff Sims

    2001-11-09

    The civil construction for the MiniBooNE project includes a 50-m decay path and beam absorbers. The decay path is a six-foot diameter corrugated metal pipe (CMP). To prevent activation of the groundwater, the CMP and beam absorbers are surrounded by crushed aggregate, and enclosed in a double-walled geotextile membrane, referred to as the liner. The minimum distance from the beam centerline to the liner is 10 feet. The double-wall construction of the liner forms three regions, the containment volume, the interstitial volume, and the exterior. Each of these volumes is connected to monitoring wells at both the upstream and downstream ends of the decay volume, i.e. a total of six monitoring pipes extend to the surface. To confirm the integrity of the liner system following its placement, the firm Earth Tech was contracted to perform tests. Michael Williams was the primary contact with Earth Tech. The following is the report from Earth Tech, with minor changes in the interest of clarity. A sketch of the decay region is shown; only one of the layers of the liner is shown, and only one monitoring port. At the time of these tests, the excavation in general, but particularly in the vicinity of the monitoring wells had not been backfilled in the final grade, as indicated by the dashed lines.

  16. On the metallicity of open clusters. III. Homogenised sample

    NASA Astrophysics Data System (ADS)

    Netopil, M.; Paunzen, E.; Heiter, U.; Soubiran, C.

    2016-01-01

    Context. Open clusters are known as excellent tools for various topics in Galactic research. For example, they allow accurately tracing the chemical structure of the Galactic disc. However, the metallicity is known only for a rather low percentage of the open cluster population, and these values are based on a variety of methods and data. Therefore, a large and homogeneous sample is highly desirable. Aims: In the third part of our series we compile a large sample of homogenised open cluster metallicities using a wide variety of different sources. These data and a sample of Cepheids are used to investigate the radial metallicity gradient, age effects, and to test current models. Methods: We used photometric and spectroscopic data to derive cluster metallicities. The different sources were checked and tested for possible offsets and correlations. Results: In total, metallicities for 172 open cluster were derived. We used the spectroscopic data of 100 objects for a study of the radial metallicity distribution and the age-metallicity relation. We found a possible increase of metallicity with age, which, if confirmed, would provide observational evidence for radial migration. Although a statistical significance is given, more studies are certainly needed to exclude selection effects, for example. The comparison of open clusters and Cepheids with recent Galactic models agrees well in general. However, the models do not reproduce the flat gradient of the open clusters in the outer disc. Thus, the effect of radial migration is either underestimated in the models, or an additional mechanism is at work. Conclusions: Apart from the Cepheids, open clusters are the best tracers for metallicity over large Galactocentric distances in the Milky Way. For a sound statistical analysis, a sufficiently large and homogeneous sample of cluster metallicities is needed. Our compilation is currently by far the largest and provides the basis for several basic studies such as the statistical

  17. Turbulator for a liner cooling jacket

    NASA Technical Reports Server (NTRS)

    Hoag, Kevin L. (Inventor)

    1995-01-01

    A turbulator for a liner cooling jacket includes a metal panel which is suitable to be coiled into a generally cylindrical shape so as to be placed in a relief area between an engine cylinder block and a cylinder liner. The relief area may be machined into either the block or the cylinder liner and the metal panel is formed with a pattern of protuberances shaped like corrugations. In one embodiment, the corrugations have a shape similar to a sine wave and are arranged in a plurality of generally parallel axial segments. The corrugation wave pattern of one segment may be the same as its adjacent segment or may be staggered by one corrugation which would mean one-half of a full wave cycle. The corrugation pattern in the turbulator panel may be created by any one of various stamping or forming operations and when placed between the cylinder liner and block, increases turbulence of the cooling liquid in order to enhance heat transfer.

  18. Solubilization of Fe(III) oxide-bound trace metals by a dissimilatory Fe(III) reducing bacterium

    NASA Astrophysics Data System (ADS)

    Zachara, John M.; Fredrickson, Jim K.; Smith, Steven C.; Gassman, Paul L.

    2001-01-01

    Trace metals associate with Fe(III) oxides as adsorbed or coprecipitated species, and consequently, the biogeochemical cycles of iron and the trace metals are closely linked. This communication investigated the solubilization of coprecipitated Co(III) and Ni(II) from goethite (α-FeOOH) during dissimilatory bacterial iron reduction to provide insights on biogeochemical factors controlling trace-element fluxes in anoxic environments. Suspensions of homogeneously substituted Co-FeOOH (50 mmol/L as Co 0.01Fe 0.99OOH; 57Co-labeled) in eight different buffer/media solutions were inoculated with a facultative, metal-reducing bacteria isolated from groundwater ( Shewanella putrefacians CN32), and incubated under strictly anaerobic conditions for periods up to 32 days. Lactate (30 mmol/L) was provided as an electron donor. Growth and non-growth promoting conditions were established by adding or withholding PO 4 and/or trace metals ( 60Co-labeled) from the incubation media. Anthraquinone disulfonate (AQDS; 100 μmol/L) was added to most suspensions as an electron shuttle to enhance bacterial reduction. Solutions were buffered at circumneutral pH with either PIPES or bicarbonate buffers. Solid and liquid samples were analyzed at intermediate and final time points for aqueous and sorbed/precipitated (by HCl extraction) Fe(II) and Co(II). The bioreduced solids were analyzed by X-ray diffraction and field-emission electron microscopy at experiment termination. Ni-FeOOH (Ni 0.01Fe 0.99OOH) was used for comparison in select experiments. Up to 45% of the metal containing FeOOH was bioreduced; growth-supporting conditions did not enhance reduction. The biogenic Fe(II) strongly associated with the residual Fe(III) oxide as an undefined sorbed phase at low fractional reduction in PIPES buffer, and as siderite (FeCO 3) in bicarbonate buffer or as vivianite [Fe 3(PO 4) 2 · 8H 2O] when P was present. Cobalt(III) was reduced to Co(II) in proportion to its mole ratio in the solid. The

  19. Combustor liner construction

    NASA Technical Reports Server (NTRS)

    Craig, H. M.; Wagner, W. B.; Strock, W. J. (Inventor)

    1983-01-01

    A combustor liner is fabricated from a plurality of individual segments each containing counter/parallel Finwall material and are arranged circumferentially and axially to define the combustion zone. Each segment is supported by a hook and ring construction to an opened lattice frame with sufficient tolerance between the hook and ring to permit thermal expansion with a minimum of induced stresses.

  20. One-Liners

    ERIC Educational Resources Information Center

    Hathaway, Nan

    2008-01-01

    This article describes an exercise appropriate for all grade levels. This exercise is based on a book of Picasso's contour drawings called "Picasso's One-Liners," which combines a delightful assortment of one-line drawings with accompanying one-line quotes. Students are given a stack of copy paper and a black fine-tip marker. Students then take…

  1. Bioactivity of pyridine-2-thiolato-1-oxide metal complexes: Bi(III), Fe(III) and Ga(III) complexes as potent anti-Mycobacterium tuberculosis prospective agents.

    PubMed

    Machado, Ignacio; Marino, Leonardo Biancolino; Demoro, Bruno; Echeverría, Gustavo A; Piro, Oscar E; Leite, Clarice Q F; Pavan, Fernando R; Gambino, Dinorah

    2014-11-24

    In the search for new therapeutic tools against tuberculosis and to further address the therapeutic potential of pyridine-2-thiol 1-oxide (Hmpo) metal complexes, two new octahedral [M(III)(mpo)3] complexes, with M = Ga or Bi, were synthesized and characterized in the solid state and in solution. Attempts to crystallize [Ga(III)(mpo)3] in CH2Cl2 led to single crystals of the reaction product [GaCl(mpo)2], where the gallium(III) ion is in a square basis pyramidal environment, trans-coordinated at the basis to two pyridine-2-thiolato 1-oxide anions acting as bidentate ligands through their oxygen and sulfur atoms. The biological activity of the new [M(III)(mpo)3] complexes together with that of the previously reported Fe(III) analogous compound and the pyridine-2-thiol 1-oxide sodium salt (Na mpo) was evaluated on Mycobacterium tuberculosis. The compounds showed excellent activity, both in the standard strain H37Rv ATCC 27294 (pan-susceptible) and in five clinical isolates that are resistant to the standard first-line anti-tuberculosis drugs isoniazid and rifampicin. These pyridine-2-thiol 1-oxide derivatives are promising compounds for the treatment of resistant tuberculosis.

  2. Bioactivity of pyridine-2-thiolato-1-oxide metal complexes: Bi(III), Fe(III) and Ga(III) complexes as potent anti-Mycobacterium tuberculosis prospective agents.

    PubMed

    Machado, Ignacio; Marino, Leonardo Biancolino; Demoro, Bruno; Echeverría, Gustavo A; Piro, Oscar E; Leite, Clarice Q F; Pavan, Fernando R; Gambino, Dinorah

    2014-11-24

    In the search for new therapeutic tools against tuberculosis and to further address the therapeutic potential of pyridine-2-thiol 1-oxide (Hmpo) metal complexes, two new octahedral [M(III)(mpo)3] complexes, with M = Ga or Bi, were synthesized and characterized in the solid state and in solution. Attempts to crystallize [Ga(III)(mpo)3] in CH2Cl2 led to single crystals of the reaction product [GaCl(mpo)2], where the gallium(III) ion is in a square basis pyramidal environment, trans-coordinated at the basis to two pyridine-2-thiolato 1-oxide anions acting as bidentate ligands through their oxygen and sulfur atoms. The biological activity of the new [M(III)(mpo)3] complexes together with that of the previously reported Fe(III) analogous compound and the pyridine-2-thiol 1-oxide sodium salt (Na mpo) was evaluated on Mycobacterium tuberculosis. The compounds showed excellent activity, both in the standard strain H37Rv ATCC 27294 (pan-susceptible) and in five clinical isolates that are resistant to the standard first-line anti-tuberculosis drugs isoniazid and rifampicin. These pyridine-2-thiol 1-oxide derivatives are promising compounds for the treatment of resistant tuberculosis. PMID:25261824

  3. Composite heat pipe development status: Development of lightweight prototype carbon-carbon heat pipe with integral fins and metal foil liner

    NASA Technical Reports Server (NTRS)

    Juhasz, Albert J.; Rovang, Richard D.

    1995-01-01

    This report discusses development and proof-of-concept testing of a new lightweight carbon-carbon (C-C) space radiator heat pipe, carried out under the NASA Civil Space Technology Initiative (CSTI) High Capacity Power Program. The prototype heat pipe, equipped with a niobium-zirconium foil liner, was filled with potassium working fluid and tested for 11 hours, including startup from ambient temperature with the working fluid initially in the frozen state to near 700 K condenser temperature. Steady-state heat pipe input power during testing was facility limited to about 300 watts. Post test inspection showed the heat pipe to be in excellent condition after eight thermal cycles from ambient to steady-state operating temperature. Utilization of other liner materials and working fluids would greatly extend the spectrum of service temperatures for this technology, with potential applications ranging from small spacecraft heat rejection to aircraft and terrestrial uses.

  4. Preparation of manganese(II), chromium(III) and ferric(III) oxides nanoparticles in situ metal citraconate complexes frameworks.

    PubMed

    Refat, Moamen S

    2014-12-10

    The new reactions of some divalent and trivalent transition metal ions (Mn(II), Cr(III), and Fe(III)) with citraconic acid has been studied. The obtained results indicate the formation of citraconic acid compounds with molar ratio of metal to citraconic acid of 2:2 or 2:3 with general formulas Mn2(C5H4O4)2 or M2(C5H4O4)3⋅nH2O where n=6 for Cr, and Fe(III). The thermal decomposition of the crystalline solid complexes was investigated. The IR spectra of citraconate suggested that the carboxylic groups are bidentatically bridging and chelating. In the course of decomposition the complexes are dehydrated and then decompose either directly to oxides in only one step or with intermediate formation of oxocarbonates. This proposal dealing the preparation of MnO2, Fe2O3 and Cr2O3 nanoparticles. The crystalline structure of oxide products were checked by X-ray powder diffraction (XRD), and the morphology of particles by scanning electron microscopy (SEM). PMID:24952090

  5. A Liner Breakage in Total Hip Arthroplasty after Using 1st Generation Highly Cross Linked Polyethylene Mated against 36-mm Metal Head: A Case Report

    PubMed Central

    Choi, Won-Kee; Chae, Seung-Bum; Kim, Dong-Young

    2015-01-01

    It has been known the highly cross linked polyethylene (HXLPE) has an advantage of improved wear rate. However, the alteration in mechanical properties such as decreased tensile yield and fatigue strength make concerns about fragility of HXLPE. We experienced a case of HXLPE breakage. But, this case of liner breakage happened although patient belonged to normal BMI and proper acetabular cup position so called "safe zone" on radiographs. So, we report this case with reference review. PMID:27536625

  6. Polished rod liner puller assmbly

    SciTech Connect

    Baxter, B.V.

    1990-01-02

    This patent describes a polished rod liner puller assembly operable with a well casing head assembly to remove a polished rod liner member of a polished rod liner assembly from a well. It comprises: a work table assembly operable to be placed around the well casing head assembly and enclose the polished rod liner assembly; a base plate assembly mounted on the work table assembly; a piston and cylinder jack assembly mounted on the base plate assembly and extended upwardly therefrom; and a winged rod clamp assembly connectable to the piston and cylinder jack assembly and to a polished rod member of the polished rod liner assembly and operable on actuation of the piston and cylinder jack assembly to axially move the polished rod member and the polished rod liner member to remove the polished rod liner member from the well.

  7. Modeling of water outgassing from metal surfaces (III)

    SciTech Connect

    Minxu Li; H. F. Dylla

    1995-06-01

    A model of water adsorption on metal oxide layers and water outgassing from metal surfaces has been developed. The oxide layer is assumed to have porous structure and a pore length (l) distribution of l/l{sup 2}. Numerical evaluation shows that the quantity of water adsorbed is logarithmic with time within a certain time range as experimentally observed. The outgassing rate from surfaces with adsorbed water distributed uniformly on the inner surfaces of individual pores is shown analytically to be inversely proportional to time. This result is consistent with frequently observed pumpdown curves.

  8. A Mononuclear Nonheme Iron(III)-Peroxo Complex Binding Redox-Inactive Metal Ions†

    PubMed Central

    Lee, Yong-Min; Bang, Suhee; Kim, Yun Mi; Cho, Jaeheung; Hong, Seungwoo; Nomura, Takashi; Ogura, Takashi; Troeppner, Oliver; Ivanović-Burmazović, Ivana

    2014-01-01

    Redox-inactive metal ions that function as Lewis acids play pivotal roles in modulating reactivities of oxygen-containing metal complexes in a variety of biological and biomimetic reactions, including dioxygen activation/formation and functionalization of organic substrates. Mononuclear nonheme iron(III)-peroxo species are invoked as active oxygen intermediates in the catalytic cycles of dioxygen activation by nonheme iron enzymes and their biomimetic compounds. Here, we report mononuclear nonheme iron(III)-peroxo complexes binding redox-inactive metal ions, [(TMC)FeIII(O2)]+-M3+ (M3+ = Sc3+ and Y3+; TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), which are characterized spectroscopically as a ‘side-on’ iron(III)-peroxo complex binding a redox-inactive metal ion, (TMC)FeIII-(μ,η2:η2-O2)-M3+ (2-M). While an iron(III)-peroxo complex, [(TMC)FeIII(O2)]+, does not react with electron donors (e.g., ferrocene), one-electron reduction of the iron(III)-peroxo complexes binding redox-inactive metal ions occurs readily upon addition of electron donors, resulting in the generation of an iron(IV)-oxo complex, [(TMC)FeIV(O)]2+ (4), via heterolytic O-O bond cleavage of the peroxide ligand. The rates of the conversion of 2-M to 4 are found to depend on the Lewis acidity of the redox-inactive metal ions and the oxidation potential of the electron donors. We have also determined the fundamental electron-transfer properties of 2-M, such as the reduction potential and the reorganization energy in electron-transfer reaction. Based on the results presented herein, we have proposed a mechanism for the reactions of 2-M and electron donors; the reduction of 2-M to the reduced species, (TMC)FeII-(O2)-M3+ (2’-M), is the rate-determining step, followed by heterolytic O-O bond cleavage of the reduced species to form 4. The present results provide a biomimetic example demonstrating that redox-inactive metal ions bound to an iron(III)-peroxo intermediate play a

  9. Atlas performance and imploding liner parameter space

    SciTech Connect

    Reinovsky, R.; Lindemuth, I. R.; Atchison, W. L.; Cochrane, J. C. , Jr.; Faehl, R. J.

    2002-01-01

    Ultra-high magnetic fields have many applications in the confining and controlling plasmas and in exploring electron physics as manifested in the magnetic properties of materials. Another application of high fields is the acceleration of metal conductors to velocities higher than that achievable with conventional high explosive drive or gas guns. The Atlas pulse power system is the world's first pulse power system specifically designed to implode solid and near-solid density metal liners for use in pulse power hydrodynamic experiments. This paper describes the Atlas system during the first year of its operational life at Los Alamos, (comprising 10-15 implosion experiments); describes circuit models that adequately predicted the bulk kinematic behavior of liner implosions; and shows how those (now validated) models can be used to describe the range of parameters accessible through Atlas implosions.

  10. The evolution of galaxies. III - Metal-enhanced star formation

    NASA Technical Reports Server (NTRS)

    Talbot, R. J., Jr.; Arnett, W. D.

    1973-01-01

    The problem of the paucity of low-metal-abundance low-mass stars is discussed. One alternative to the variable-initial-mass-function (VIMF) solution is proposed. It is shown that this solution - metal-enhanced star formation - satisfies the classical test which prompted the VIMF hypothesis. Furthermore, with no additional parameters it provides improved fits to other tests - e.g., inhomogeneities in the abundances in young stars, concordance of all nucleo-cosmochronologies, and a required yield of heavy-element production which is consistent with current stellar evolution theory. In this model the age of the Galaxy is 18.6 plus or minus 5.7 b.y.

  11. Infrared spectra of group III A metal oxides

    NASA Technical Reports Server (NTRS)

    Lynch, D. A., Jr.

    1972-01-01

    The measurement of infrared frequencies of metal-oxygen species which could be formed in the matrix and to investigate with an oxygen-18 enrichment study the controversy on the vibrational assignments for the suboxide. Several new molecules, Al3O2, Ga3O, In3O, In4O2, IntaO, IntaO2, and In2WO4, were found by mass spectrometric sampling to exist in extremely minor concentrations in the vapor phase. The latter three species were formed by reaction with the crucible materials and were unimportant for an infrared analysis. The infrared spectroscopic measurements were obtained by the matrix isolation technique of molecular beam sampling. The MO2 species were formed by direct reaction between metal and O2 in the matrix. A C2v structure and an O-M-O bond angle near 40 deg was favored for these molecules by analogy with a similar investigation of the alkali metals. The vibrational frequencies which were determined are given.

  12. Configuration Effects on Liner Performance

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Brown, Martha C.; Jones, Michael G.; Howerton, Brian M.

    2012-01-01

    The acoustic performance of a duct liner depends not only on the intrinsic properties of the liner but also on the configuration of the duct in which it is used. A series of experiments is performed in the NASA Langley Research Center Curved Duct Test Rig (at Mach 0.275) to evaluate the effect of duct configuration on the acoustic performance of single degree of freedom perforate-over-honeycomb liners. The liners form the sidewalls of the duct's test section. Variations of duct configuration include: asymmetric (liner on one side and hard wall opposite) and symmetric (liner on both sides) wall treatment; inlet and exhaust orientation, in which the sound propagates either against or with the flow; and straight and curved flow path. The effect that duct configuration has on the overall acoustic performance, particularly the shift in frequency and magnitude of peak attenuation, is quantified. The redistribution of incident mode content is shown. The liners constitute the side walls of the liner test section and the scatter of incident horizontal order 1 mode by the asymmetric treatment and order 2 mode by the symmetric treatment into order 0 mode is shown. Scatter of order 0 incident modes into higher order modes is also shown. This redistribution of mode content is significant because it indicates that the liner design can be manipulated such that energy is scattered into more highly attenuated modes, thus enhancing liner performance.

  13. High temperature combustor liner

    SciTech Connect

    Able, E.C.; Gibler, M.J.

    1992-05-19

    This patent describes a combustor liner. It comprises a support panel having a plurality of apertures therein, which apertures each have a wide portion and a narrow portion, a plurality of ceramic tiles, each tile having a knob upstanding on a neck from a face of such tile, each of the knobs being sized to fit through the larger end of the apertures but not the smaller end thereof, the knobs being inserted through the larger end of the apertures and shifted over the smaller end thereof and over the support panel, the necks passing therethrough and supporting the tiles below the support panel, holding means to secure the knobs proximate the smaller ends of the apertures and means to mount the support panel to the combustor line so as to mount the tiles before the liner as a heat shield therefor.

  14. Double shell liner implosions

    SciTech Connect

    Sorokin, S. A.; Chaikovsky, S. A.

    1997-05-05

    Experiments on the double shell liner (DSL) implosions with and without an initial axial magnetic were performed on the SNOP-3 pulse generator (1.1 MA, 100 ns). In implosions of a DSL without an initial axial magnetic field, high radial compressions of the inner shell were observed, as in previous experiments with an initial axial magnetic field. Possible mechanisms for the formation of the initial azimuthal magnetic field are discussed.

  15. Microsecond ramp compression of a metallic liner driven by a 5 MA current on the SPHINX machine using a dynamic load current multiplier pulse shaping

    NASA Astrophysics Data System (ADS)

    d'Almeida, T.; Lassalle, F.; Morell, A.; Grunenwald, J.; Zucchini, F.; Loyen, A.; Maysonnave, T.; Chuvatin, A. S.

    2013-09-01

    SPHINX is a 6 MA, 1-μs Linear Transformer Driver (LTD) operated by the CEA Gramat (France) and primarily used for imploding Z-pinch loads for radiation effects studies. Among the options that are currently being evaluated to improve the generator performances are an upgrade to a 20 MA, 1-μs LTD machine and various power amplification schemes, including a compact Dynamic Load Current Multiplier (DLCM). A method for performing magnetic ramp compression experiments, without modifying the generator operation scheme, was developed using the DLCM to shape the initial current pulse in order to obtain the desired load current profile. In this paper, we discuss the overall configuration that was selected for these experiments, including the choice of a coaxial cylindrical geometry for the load and its return current electrode. We present both 3-D Magneto-hydrodynamic and 1D Lagrangian hydrodynamic simulations which helped guide the design of the experimental configuration. Initial results obtained over a set of experiments on an aluminium cylindrical liner, ramp-compressed to a peak pressure of 23 GPa, are presented and analyzed. Details of the electrical and laser Doppler interferometer setups used to monitor and diagnose the ramp compression experiments are provided. In particular, the configuration used to field both homodyne and heterodyne velocimetry diagnostics in the reduced access available within the liner's interior is described. Current profiles measured at various critical locations across the system, particularly the load current, enabled a comprehensive tracking of the current circulation and demonstrate adequate pulse shaping by the DLCM. The liner inner free surface velocity measurements obtained from the heterodyne velocimeter agree with the hydrocode results obtained using the measured load current as the input. An extensive hydrodynamic analysis is carried out to examine information such as pressure and particle velocity history profiles or magnetic

  16. Microsecond ramp compression of a metallic liner driven by a 5 MA current on the SPHINX machine using a dynamic load current multiplier pulse shaping

    SciTech Connect

    D'Almeida, T.; Lassalle, F.; Morell, A.; Grunenwald, J.; Zucchini, F.; Loyen, A.; Maysonnave, T.; Chuvatin, A. S.

    2013-09-15

    SPHINX is a 6 MA, 1-μs Linear Transformer Driver (LTD) operated by the CEA Gramat (France) and primarily used for imploding Z-pinch loads for radiation effects studies. Among the options that are currently being evaluated to improve the generator performances are an upgrade to a 20 MA, 1-μs LTD machine and various power amplification schemes, including a compact Dynamic Load Current Multiplier (DLCM). A method for performing magnetic ramp compression experiments, without modifying the generator operation scheme, was developed using the DLCM to shape the initial current pulse in order to obtain the desired load current profile. In this paper, we discuss the overall configuration that was selected for these experiments, including the choice of a coaxial cylindrical geometry for the load and its return current electrode. We present both 3-D Magneto-hydrodynamic and 1D Lagrangian hydrodynamic simulations which helped guide the design of the experimental configuration. Initial results obtained over a set of experiments on an aluminium cylindrical liner, ramp-compressed to a peak pressure of 23 GPa, are presented and analyzed. Details of the electrical and laser Doppler interferometer setups used to monitor and diagnose the ramp compression experiments are provided. In particular, the configuration used to field both homodyne and heterodyne velocimetry diagnostics in the reduced access available within the liner's interior is described. Current profiles measured at various critical locations across the system, particularly the load current, enabled a comprehensive tracking of the current circulation and demonstrate adequate pulse shaping by the DLCM. The liner inner free surface velocity measurements obtained from the heterodyne velocimeter agree with the hydrocode results obtained using the measured load current as the input. An extensive hydrodynamic analysis is carried out to examine information such as pressure and particle velocity history profiles or magnetic

  17. Dissolution of iron(III)(HYDR)oxides by metal-EDTA-complexes

    SciTech Connect

    Nowack, B.; Sigg, L.

    1996-10-01

    The dissolution of Fe(III)(hydroxides) (goethite and hydrous ferric oxide) by metal-EDTA complexes occurs by ligand-promoted dissolution. The process is initiated by adsorption of the metal-EDTA to the surface, dissociation of the complex at the surface and release of Fe(III)EDTA into solution. The dissolution rate is decreased to a great extent if EDTA is complexed by metals in comparison to uncomplexed EDTA. The rate decreases in the order EDTA >> CaEDTA > PbEDTA > ZnEDTA > CuEDTA > Co(II)EDTA > NiEDTA. Two different rate-limiting steps determine the system: (1) detachment of Fe(III) from the oxide-structure and (2) dissociation of the metal-EDTA complexes. In the case of goethite, step (1) is more important than (2) and the difference in the dissolution rate for several metals is small. In the case of hydrous ferric oxide, step (2) is rate-limiting and the effect of the complexed metal is very pronounced.

  18. Dissolution of Fe(III)(hydr) oxides by metal-EDTA complexes

    SciTech Connect

    Nowack, B.; Sigg, L. |

    1997-03-01

    The dissolution of Fe(III)(hydr)oxides (goethite and hydrous ferric oxide) by metal-EDTA complexes occurs by ligand-promoted dissolution. The process is initiated by the adsorption of metal-EDTA complexes to the surface and is followed by the dissociation of the complex at the surface and the release of Fe(III)EDTA into solution. The dissolution rate is decreased to a great extent if EDTA is complexed by metals in comparison to the uncomplexed EDTA. The rate decreases in the order EDTA > CaEDTA > PbEDTA > ZnEDTA > CuEDTA > Co(II)EDTA > NiEDTA. Two different rate-limiting steps determine the dissolution process: (1) detachment of Fe(III) from the oxide-structure and (2) dissociation of the metal-EDTA complexes. In the case of goethite, step 1 is slower than step 2 and the dissolution rates by various metals are similar. In the case of hydrous ferric oxide, step 2 is rate-limiting and the effect of the complexed metal is very pronounced. 35 refs., 11 figs., 4 tabs.

  19. Preparations to ship EPICOR liners

    SciTech Connect

    Queen, S P

    1983-06-01

    The sampling and analysis of the hydrogen rich atmosphere of the 49 EPICOR II ion-exchange prefilter liners generated in the decontamination of radioactive water at TMI-2 will provide data to ensure safe storage and shipment of highly loaded ion-exchange media. This report discusses the prototype gas sampling tool used to breech the containment of the liners, the tool support equipment for sampling and inerting the liners, and the characterization program used for determining the radiolytic hydrogen generation rates in the liners.

  20. Unveiling the liner nature of NGC1052

    NASA Astrophysics Data System (ADS)

    Diniz, S. I. F.; Pastoriza, M. G.; Riffel, R.; Riffel, R. A.; Diniz, M. R.; Storchi-Bergmann, T.

    2014-10-01

    NGC 1052 is an E4 galaxy and classified as a typical LINER harboring a stellar rotating disk. However, the central region is spectroscopically unusual with broad optical emission lines, the nature of its emission line gas remains unclear. According to recent studies NGC 1052 exhibit Hα luminosities an order of magnitude above that estimated for an evolved population of extreme horizontal branch stars. Their Hα equivalent widths and optical-to-near infrared (NIR) spectral energy distributions are consistent with them being young stellar clusters aged < 7 Myr, and according to previous works, NGC 1052 may have experienced a merger event about 1 Gyr ago. There are mainly three possibilities to explain LINER's spectra: i) post asymptotic giant branch stars (post-AGB) that ionize their rapidly expanding shells, (ii) active galactic nuclei (AGNs) powered by the in fall of matter into an accretion disk, and (iii) shocks. The stellar population (SP) of AGNs shows an excess of intermediate age stars. Besides, NIR stellar population studies have revealed that the continuum of active galaxies is dominated by the contribution of intermediate age stellar populations. Hot dust emission unresolved is also commonly detected in NIR nuclear spectra of galaxies Seyfert and LINERs. Aimed to discriminate the dominant ionizing source of NGC 1052 we present preliminary results of high spatial resolution integral field spectroscopy, taken with gemini NIFS to map the dominant stellar population, as well as disentangling the featureless and hot dust components.

  1. Metallosis after Exchange of the Femoral Head and Liner following Ceramic Acetabular Liner Dissociation in Total Hip Arthroplasty with a Modular Layered Acetabular Component.

    PubMed

    Takasago, Tomoya; Goto, Tomohiro; Wada, Keizo; Hamada, Daisuke; Iwame, Toshiyuki; Matsuura, Tetsuya; Nagamachi, Akihiro; Sairyo, Koichi

    2016-01-01

    The type of bearing material that should be used in revision surgery after the failure of ceramic-on-ceramic total hip arthroplasty (THA) remains controversial. In the case of ceramic fracture, the residual ceramic particles can cause consequent metallosis when metal implants are used for revision THA. On the other hand, in the case of THA failure without ceramic fracture, revision THA with a metal femoral head provides satisfactory results. We report an unusual case of progressive osteolysis due to metallosis that developed after revision THA for ceramic liner dissociation without a liner fracture performed using a metal femoral head and polyethylene liner. The residual metal debris and abnormal pumping motion of the polyethylene liner due to the breakage of the locking system or the aspherical metal shell being abraded by the ceramic head seemed to be the cause of the progressive osteolysis. PMID:27648325

  2. Metallosis after Exchange of the Femoral Head and Liner following Ceramic Acetabular Liner Dissociation in Total Hip Arthroplasty with a Modular Layered Acetabular Component

    PubMed Central

    Hamada, Daisuke; Iwame, Toshiyuki; Sairyo, Koichi

    2016-01-01

    The type of bearing material that should be used in revision surgery after the failure of ceramic-on-ceramic total hip arthroplasty (THA) remains controversial. In the case of ceramic fracture, the residual ceramic particles can cause consequent metallosis when metal implants are used for revision THA. On the other hand, in the case of THA failure without ceramic fracture, revision THA with a metal femoral head provides satisfactory results. We report an unusual case of progressive osteolysis due to metallosis that developed after revision THA for ceramic liner dissociation without a liner fracture performed using a metal femoral head and polyethylene liner. The residual metal debris and abnormal pumping motion of the polyethylene liner due to the breakage of the locking system or the aspherical metal shell being abraded by the ceramic head seemed to be the cause of the progressive osteolysis. PMID:27648325

  3. Metallosis after Exchange of the Femoral Head and Liner following Ceramic Acetabular Liner Dissociation in Total Hip Arthroplasty with a Modular Layered Acetabular Component

    PubMed Central

    Hamada, Daisuke; Iwame, Toshiyuki; Sairyo, Koichi

    2016-01-01

    The type of bearing material that should be used in revision surgery after the failure of ceramic-on-ceramic total hip arthroplasty (THA) remains controversial. In the case of ceramic fracture, the residual ceramic particles can cause consequent metallosis when metal implants are used for revision THA. On the other hand, in the case of THA failure without ceramic fracture, revision THA with a metal femoral head provides satisfactory results. We report an unusual case of progressive osteolysis due to metallosis that developed after revision THA for ceramic liner dissociation without a liner fracture performed using a metal femoral head and polyethylene liner. The residual metal debris and abnormal pumping motion of the polyethylene liner due to the breakage of the locking system or the aspherical metal shell being abraded by the ceramic head seemed to be the cause of the progressive osteolysis.

  4. Cobalt(III), a probe of metal binding sites of Escherichia coli alkaline phosphatase.

    PubMed Central

    Anderson, R A; Vallee, B L

    1975-01-01

    To facilitate the study of individual metal binding sites of polymeric metalloproteins, conversion of exchange-labile Co(II) in E. coli alkaline phosphatase (EC 3.1.3.1) to exchange-inert Co(III) was examined. Oxidation of Co(II) alkaline phosphatase with hydrogen peroxide results in a single absorption maximum at 530 nm and loss both of the characteristic electron paramagnetic signal and of enzymatic activity. Zinc neither reactivates this enzyme nor displaces the oxidized cobalt atoms. Metal and amino-acid analyses demonstrate that oxidation alters neither cobalt binding nor amino-acid composition of the enzyme. Al data are consistent with the conclusion that hydrogen peroxide oxidizes Co(II) in alkaline phosphatase to Co(III). Polymeric metalloenzymes can contain different categories of metal atoms serving in catalysis, structure stabilization, and/or control and exerting their effects independently or interdependently. The in situ conversion of exchange-labile Co(II) to exchange-stable (Co(III) offers a method to selectively and differentially "freeze" cobalt atoms at their respective binding sites. The accompanying spectral changes and concomitant retardation in ligand exchange reactions may be used to differentiate between specific metal binding sites that serve different roles in polymeric metalloenzymes. PMID:164026

  5. Optimizing liner implosions for high energy density physics experiments

    SciTech Connect

    Ekdahl, C.; Humphries, S. Jr.

    1996-12-31

    Cylindrical metal shells imploded by magnetic fields - liners - are used as kinetic energy drivers for high energy density physics experiments in hydrodynamics and dynamic material property measurements. There are at least three ways in which liners have been, or are expected to be, used to produce high energy density, i.e., high pressure, in target materials. A common approach uses the liner as a convergent flyer plate, which impacts a material target cylinder after having been shocklessly accelerated across an intervening gap. The resultant shock and piston hydrodynamic flow in the target are used in exploration of a wide variety of phenomena and material properties. Another common method is to slowly compress a liner containing a material sample in a such fashion that little heating occurs. This technique is most useful for investigated physical properties at low temperature and extreme density. Finally, one can use a hybrid approach to shock heat with an impacting liner followed by slower adiabatic, if not isentropic, compression to explore material properties in extrema. The magnetic fields for driving these liners may be produced by either high explosive pulsed power generators or by capacitor banks. Here we will consider only capacitor banks.

  6. Energy efficient engine pin fin and ceramic composite segmented liner combustor sector rig test report

    NASA Technical Reports Server (NTRS)

    Dubiel, D. J.; Lohmann, R. P.; Tanrikut, S.; Morris, P. M.

    1986-01-01

    Under the NASA-sponsored Energy Efficient Engine program, Pratt and Whitney has successfully completed a comprehensive test program using a 90-degree sector combustor rig that featured an advanced two-stage combustor with a succession of advanced segmented liners. Building on the successful characteristics of the first generation counter-parallel Finwall cooled segmented liner, design features of an improved performance metallic segmented liner were substantiated through representative high pressure and temperature testing in a combustor atmosphere. This second generation liner was substantially lighter and lower in cost than the predecessor configuration. The final test in this series provided an evaluation of ceramic composite liner segments in a representative combustor environment. It was demonstrated that the unique properties of ceramic composites, low density, high fracture toughness, and thermal fatigue resistance can be advantageously exploited in high temperature components. Overall, this Combustor Section Rig Test program has provided a firm basis for the design of advanced combustor liners.

  7. Metal-Free Asymmetric Synthesis of Indanes through Chiral Hypervalent Iodine(III)-Mediated Ring Contraction.

    PubMed

    Ahmad, Anees; Silva, Luiz F

    2016-03-01

    The iodine(III)-mediated asymmetric oxidative rearrangement of 1,2-dihydronaphthalenes was investigated to prepare optically active 1-substituted indanes. The chiral hypervalent iodine species is generated in situ from a chiral aryl iodide, prepared in 94% yield in one step. This metal-free protocol was applied to different cyclic alkenes, substituted with oxygen, with nitrogen, or at position 1 with aryl or methyl. Indanes can be isolated as an acetal or alcohol in up to 78% ee. PMID:26866897

  8. III-V Nanowire Complementary Metal-Oxide Semiconductor Transistors Monolithically Integrated on Si.

    PubMed

    Svensson, Johannes; Dey, Anil W; Jacobsson, Daniel; Wernersson, Lars-Erik

    2015-12-01

    III-V semiconductors have attractive transport properties suitable for low-power, high-speed complementary metal-oxide-semiconductor (CMOS) implementation, but major challenges related to cointegration of III-V n- and p-type metal-oxide-semiconductor field-effect transistors (MOSFETs) on low-cost Si substrates have so far hindered their use for large scale logic circuits. By using a novel approach to grow both InAs and InAs/GaSb vertical nanowires of equal length simultaneously in one single growth step, we here demonstrate n- and p-type III-V MOSFETs monolithically integrated on a Si substrate with high I(on)/I(off) ratios using a dual channel, single gate-stack design processed simultaneously for both types of transistors. In addition, we demonstrate fundamental CMOS logic gates, such as inverters and NAND gates, which illustrate the viability of our approach for large scale III-V MOSFET circuits on Si. PMID:26595174

  9. ACOUSTIC LINERS FOR TURBOFAN ENGINES

    NASA Technical Reports Server (NTRS)

    Minner, G. L.

    1994-01-01

    This program was developed to design acoustic liners for turbofan engines. This program combines results from theoretical models of wave alternation in acoustically treated passages with experimental data from full-scale fan noise suppressors. By including experimentally obtained information, the program accounts for real effects such as wall boundary layers, duct terminations, and sound modal structure. The program has its greatest use in generating a number of design specifications to be used for evaluation of trade-offs. The program combines theoretical and empirical data in designing annular acoustic liners. First an estimate of the noise output of the fan is made based on basic fan aerodynamic design variables. Then, using a target noise spectrum after alternation and the estimated fan noise spectrum, a design spectrum is calculated as their difference. Next, the design spectrum is combined with knowledge of acoustic liner performance and the liner design variables to specify the acoustic design. Details of the liner design are calculated by combining the required acoustic impedance with a mathematical model relating acoustic impedance to the physical structure of the liner. Input to the noise prediction part of the program consists of basic fan operating parameters, distance that the target spectrum is to be measured and the target spectrum. The liner design portion of the program requires the required alternation spectrum, desired values of length to height and several option selection parameters. Output from the noise prediction portion is a noise spectrum consisting of discrete tones and broadband noise. This may be used as input to the liner design portion of the program. The liner design portion of the program produces backing depths, open area ratios, and face plate thicknesses. This program is written in FORTRAN V and has been implemented in batch mode on a UNIVAC 1100 series computer with a central memory requirement of 12K (decimal) of 36 bit words.

  10. Acoustic impedance of curved multilayered duct liners

    NASA Technical Reports Server (NTRS)

    Zorumski, W. E.

    1973-01-01

    The effect of curvature of annular duct liners on the liner acoustic impedance is examined. Exact equations are derived for the impedance of point reacting liners which are made from an arbitrary number of thin cylindrical layers of porous material separated by small radially oriented cells. Equations are given for liners with convex curvature and for liners with concave curvature. For ducts with small curvature, it is shown that these equations reduce to the equations for a flat liner. It is shown, by analytical and numerical examples, that the effect of liner curvature is significant in practical noise reduction problems.

  11. Megabar liner experiments on Pegasus II

    SciTech Connect

    Lee, H.; Bartsch, R.R.; Bowers, R.L.

    1997-09-01

    Using pulsed power to implode a liner onto a target can produce high shock pressures for many interesting application experiments. With a Pegasus II facility in Los Alamos, a detailed theoretical analysis has indicated that the highest attainable pressure is around 2 Mbar for a best designed aluminum liner. Recently, an interesting composite liner design has been proposed which can boost the shock pressure performance by a factor 4 over the aluminum liner. This liner design was adopted in the first megabar (Megabar-1) liner experiment carried out on Pegasus last year to verify the design concept and to compare the effect of Rayleigh-Taylor instabilities on liner integrity with the code simulations. We present briefly the physical considerations to explain why the composite liner provides the best shock pressure performance. The theoretical modeling and performance of Megabar-1 liner are discussed. Also presented are the first experimental results and the liner design modification for our next experiment.

  12. Abundance anomalies in metal-poor stars from Population III supernova ejecta hydrodynamics

    NASA Astrophysics Data System (ADS)

    Sluder, Alan; Ritter, Jeremy S.; Safranek-Shrader, Chalence; Milosavljević, Miloš; Bromm, Volker

    2016-02-01

    We present a simulation of the long-term evolution of a Population III supernova remnant in a cosmological minihalo. Employing passive Lagrangian tracer particles, we investigate how chemical stratification and anisotropy in the explosion can affect the abundances of the first low-mass, metal-enriched stars. We find that reverse shock heating can leave the inner mass shells at entropies too high to cool, leading to carbon enhancement in the recollapsing gas. This hydrodynamic selection effect could explain the observed incidence of carbon-enhanced metal-poor stars at low metallicity. We further explore how anisotropic ejecta distributions, recently seen in direct numerical simulations of core-collapse explosions, may translate to abundances in metal-poor stars. We find that some of the observed scatter in the Population II abundance ratios can be explained by an incomplete mixing of supernova ejecta, even in the case of only one contributing enrichment event. We demonstrate that the customary hypothesis of fully mixed ejecta clearly fails if post-explosion hydrodynamics prefers the recycling of some nucleosynthetic products over others. Furthermore, to fully exploit the stellar-archaeological programme of constraining the Pop III initial mass function from the observed Pop II abundances, considering these hydrodynamical transport effects is crucial. We discuss applications to the rich chemical structure of ultrafaint dwarf satellite galaxies, to be probed in unprecedented detail with upcoming spectroscopic surveys.

  13. Cyclometalated iridium(III) complexes for phosphorescence sensing of biological metal ions.

    PubMed

    You, Youngmin; Cho, Somin; Nam, Wonwoo

    2014-02-17

    Phosphorescence signaling provides a valuable alternative to conventional bioimaging based on fluorescence. The benefits of using phosphorescent molecules include improved sensitivity and capabilities for effective elimination of background signals by time-gated acquisition. Cyclometalated Ir(III) complexes are promising candidates for facilitating phosphorescent bioimaging because they provide synthetic versatility and excellent phosphorescence properties. In this Forum Article, we present our recent studies on the development of phosphorescence sensors for the detection of metal ions based on cyclometalated iridium(III) complexes. The constructs contained cyclometalating (C^N) ligands with the electron densities and band-gap energies of the C^N ligand structures systematically varied. Receptors that chelated zinc, cupric, and chromium ions were tethered to the ligands to create phosphorescence sensors. The alterations in the C^N ligand structures had a profound influence on the phosphorescence responses to metal ions. Mechanistic studies suggested that the phosphorescence responses could be explained on the basis of the modulation of photoinduced electron transfer (PeT) from the receptor to the photoexcited iridium species. The PeT behaviors strictly adhered to the Rehm-Weller principle, and the occurrence of PeT was located in the Marcus-normal region. It is thus anticipated that improved responses will be obtainable by increasing the excited-state reduction potential of the iridium(III) complexes. Femtosecond transient absorption experiments provided evidence for the presence of an additional photophysical mechanism that involved metal-ion-induced alteration of the intraligand charge-transfer (ILCT) transition state. Utility of the mechanism by PeT and ILCT has been demonstrated for the phosphorescence sensing of biologically important transition-metal ions. In particular, the phosphorescence zinc sensor could report the presence of intracellular zinc pools by

  14. Crystal structure of class III chitinase from pomegranate provides the insight into its metal storage capacity.

    PubMed

    Masuda, Taro; Zhao, Guanghua; Mikami, Bunzo

    2015-01-01

    Chitinase hydrolyzes the β-1,4-glycosidic bond in chitin. In higher plants, this enzyme has been regarded as a pathogenesis-related protein. Recently, we identified a class III chitinase, which functions as a calcium storage protein in pomegranate (Punica granatum) seed (PSC, pomegranate seed chitinase). Here, we solved a crystal structure of PSC at 1.6 Å resolution. Although its overall structure, including the structure of catalytic site and non-proline cis-peptides, was closely similar to those of other class III chitinases, PSC had some unique structural characteristics. First, there were some metal-binding sites with coordinated water molecules on the surface of PSC. Second, many unconserved aspartate residues were present in the PSC sequence which rendered the surface of PSC negatively charged. This acidic electrostatic property is in contrast to that of hevamine, well-characterized plant class III chitinase, which has rather a positively charged surface. Thus, the crystal structure provides a clue for metal association property of PSC.

  15. Reduction of Fe(III), Mn(IV), and Toxic Metals at 100°C by Pyrobaculum islandicum

    PubMed Central

    Kashefi, Kazem; Lovley, Derek R.

    2000-01-01

    It has recently been noted that a diversity of hyperthermophilic microorganisms have the ability to reduce Fe(III) with hydrogen as the electron donor, but the reduction of Fe(III) or other metals by these organisms has not been previously examined in detail. When Pyrobaculum islandicum was grown at 100°C in a medium with hydrogen as the electron donor and Fe(III)-citrate as the electron acceptor, the increase in cell numbers of P. islandicum per mole of Fe(III) reduced was found to be ca. 10-fold higher than previously reported. Poorly crystalline Fe(III) oxide could also serve as the electron acceptor for growth on hydrogen. The stoichiometry of hydrogen uptake and Fe(III) oxide reduction was consistent with the oxidation of 1 mol of hydrogen resulting in the reduction of 2 mol of Fe(III). The poorly crystalline Fe(III) oxide was reduced to extracellular magnetite. P. islandicum could not effectively reduce the crystalline Fe(III) oxide minerals goethite and hematite. In addition to using hydrogen as an electron donor for Fe(III) reduction, P. islandicum grew via Fe(III) reduction in media in which peptone and yeast extract served as potential electron donors. The closely related species P. aerophilum grew via Fe(III) reduction in a similar complex medium. Cell suspensions of P. islandicum reduced the following metals with hydrogen as the electron donor: U(VI), Tc(VII), Cr(VI), Co(III), and Mn(IV). The reduction of these metals was dependent upon the presence of cells and hydrogen. The metalloids arsenate and selenate were not reduced. U(VI) was reduced to the insoluble U(IV) mineral uraninite, which was extracellular. Tc(VII) was reduced to insoluble Tc(IV) or Tc(V). Cr(VI) was reduced to the less toxic, less soluble Cr(III). Co(III) was reduced to Co(II). Mn(IV) was reduced to Mn(II) with the formation of manganese carbonate. These results demonstrate that biological reduction may contribute to the speciation of metals in hydrothermal environments and could

  16. Biosorption and desorption of lanthanum(III) and neodymium(III) in fixed-bed columns with Sargassum sp.: perspectives for separation of rare earth metals.

    PubMed

    Oliveira, Robson C; Guibal, Eric; Garcia, Oswaldo

    2012-01-01

    Rare earth (RE) metals are essentials for the manufacturing of high-technology products. The separation of RE is complex and expensive; biosorption is an alternative to conventional processes. This work focuses on the biosorption of monocomponent and bicomponent solutions of lanthanum(III) and neodymium(III) in fixed-bed columns using Sargassum sp. biomass. The desorption of metals with HCl 0.10 mol L(-1) from loaded biomass is also carried out with the objective of increasing the efficiency of metal separation. Simple models have been successfully used to model breakthrough curves (i.e., Thomas, Bohart-Adams, and Yoon-Nelson equations) for the biosorption of monocomponent solutions. From biosorption and desorption experiments in both monocomponent and bicomponent solutions, a slight selectivity of the biomass for Nd(III) over La(III) is observed. The experiments did not find an effective separation of the RE studied, but their results indicate a possible partition between the metals, which is the fundamental condition for separation perspectives.

  17. Characterization of Co(III) EDTA-Reducing Bacteria in Metal- and Radionuclide-Contaminated Groundwater

    SciTech Connect

    Gao, Weimin; Gentry, Terry J; Mehlhorn, Tonia L; Carroll, Sue L; Jardine, Philip M; Zhou, Jizhong

    2010-01-01

    The Waste Area Grouping 5 (WAG5) site at Oak Ridge National Laboratory has a potential to be a field site for evaluating the effectiveness of various bioremediation approaches and strategies. The site has been well studied in terms of its geological and geochemical properties over the past decade. However, despite the importance of microorganisms in bioremediation processes, the microbiological populations at the WAG5 site and their potential in bioremediation have not been similarly evaluated. In this study, we initiated research to characterize the microbial populations in WAG5 groundwater. Approximately 100 isolates from WAG5 groundwater were isolated and selected based on colony morphology. Fifty-five unique isolates were identified by BOX-PCR and subjected to further characterization. 16S rRNA sequences indicated that these isolates belong to seventeen bacterial genera including Alcaligenes (1 isolate), Aquamonas (1), Aquaspirillum (1), Bacillus (10), Brevundimonas (5), Caulobacter (7), Dechloromonas (2), Janibacter (1), Janthinobacterium (2), Lactobacillus (1), Paenibacillus (4), Pseudomonas (9), Rhodoferax (1), Sphingomonas (1), Stenotrophomonas (6), Variovorax (2), and Zoogloea (1). Metal respiration assays identified several isolates, which phylogenically belong or are close to Caulobacter, Stenotrophomonas, Bacillus, Paenibacillus and Pseudomonas, capable of reducing Co(III)EDTA- to Co(II)EDTA{sup 2-} using the defined M1 medium under anaerobic conditions. In addition, using WAG5 groundwater directly as the inoculants, we found that organisms associated with WAG5 groundwater can reduce both Fe(III) and Co(III) under anaerobic conditions. Further assays were then performed to determine the optimal conditions for Co(III) reduction. These assays indicated that addition of various electron donors including ethanol, lactate, methanol, pyruvate, and acetate resulted in metal reduction. These experiments will provide useful background information for future

  18. Liner cooling research at NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Acosta, Waldo A.

    1987-01-01

    Described are recently completed and current advanced liner research applicable to advanced small gas turbine engines. Research relating to the evolution of fuel efficient small gas turbine engines capable of meeting future commercial and military aviation needs is currently under way at NASA Lewis Research Center. As part of this research, a reverse-flow combustor geometry was maintained while different advanced liner wall cooling techniques were investigated and compared to a baseline combustor. The performance of the combustors featuring counterflow film-cooled (CFFC) panels, transpiration cooled liner walls (TRANS), and compliant metal/ceramic (CMC) walls was obtained over a range of simulated flight conditions of a 16:1 pressure ratio gas turbine engine and fuel/air ratios up to 0.034. All the combustors featured an identical fuel injection system, identical geometric configuration outline, and similar designed internal aerothermodynamics.

  19. Synthesis, spectroscopic, thermal and anticancer studies of metal-antibiotic chelations: Ca(II), Fe(III), Pd(II) and Au(III) chloramphenicol complexes

    NASA Astrophysics Data System (ADS)

    Al-Khodir, Fatima A. I.; Refat, Moamen S.

    2016-09-01

    Four Ca(II), Fe(III), Pd(II) and Au(III) complexes of chloramphenicol drug have been synthesized and well characterized using elemental analyses, (infrared, electronic, and 1H-NMR) spectra, magnetic susceptibility measurement, and thermal analyses. Infrared spectral data show that the chloramphenicol drug coordinated to Ca(II), Pd(II) and Au(III) metal ions through two hydroxyl groups with 1:1 or 1:2 M ratios, but Fe(III) ions chelated towards chloramphenicol drug via the oxygen and nitrogen atoms of amide group with 1:2 ratio based on presence of keto↔enol form. The X-ray powder diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) techniques were used to identify the nano-size particles of both iron(III) and gold(III) chloramphenicol complexes. The antimicrobial assessments of the chloramphenicol complexes were scanned and collected the results against of some kind of bacteria and fungi. The cytotoxic activity of the gold(III) complex was tested against the human colon carcinoma (HCT-116) and human hepatocellular carcinoma (HepG-2) tumor cell lines.

  20. Long-term behavior of water content and density in an earthen liner

    USGS Publications Warehouse

    Frank, T.E.; Krapac, I.G.; Stark, T.D.; Strack, G.D.

    2005-01-01

    An extensively instrumented compacted earthen liner was constructed at the Illinois State Geological Survey facility in Champaign, III. in 1987. A pond of water 0.31 m deep was maintained on top of the 7.3 m ?? 14.6 m ?? 0.9 m thick liner for 14 years. One of the goals of the project was to evaluate the long-term performance of a compacted earthen liner by monitoring the long-term changes in water content and density. The water content of the earthen liner showed no trend with depth or time. The liner density remained essentially constant from construction through excavation in 2002. The liner did not become fully saturated. Upon excavation of the liner, the degree of saturation was 80.0??6.3% after 14 years of ponding under a hydraulic head of 0.31 m. The results imply that properly designed and constructed earthen liners may reduce the possibility of pollutants leaching from municipal solid waste containment facilities by remaining partially saturated for years and maintaining the placement density. Journal of Geotechnical and Geoenvironmental Engineering ?? ASCE.

  1. Military Curricula for Vocational & Technical Education. Metals Processing Specialist, Blocks III and IV, Classroom Course 13-6.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    These curriculum materials are the second section of a four-part, secondary-postsecondary-level course in metals processing. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instruction and curriculum development in a civilian setting. Block III, Introduction to Metallic Arc Welding,…

  2. Porous, rigid metal(III)-carboxylate metal-organic frameworks for the delivery of nitric oxide

    NASA Astrophysics Data System (ADS)

    Eubank, Jarrod F.; Wheatley, Paul S.; Lebars, Gaëlle; McKinlay, Alistair C.; Leclerc, Hervé; Horcajada, Patricia; Daturi, Marco; Vimont, Alexandre; Morris, Russell E.; Serre, Christian

    2014-12-01

    The room temperature sorption properties of the biological gas nitric oxide (NO) have been investigated on the highly porous and rigid iron or chromium carboxylate based metal-organic frameworks Material Institut Lavoisier (MIL)-100(Fe or Cr) and MIL-127(Fe). In all cases, a significant amount of NO is chemisorbed at 298 K with a loading capacity that depends both on the nature of the metal cation, the structure and the presence of additional iron(II) Lewis acid sites. In a second step, the release of NO triggered by wet nitrogen gas has been studied by chemiluminescence and indicates that only a partial release of NO occurs as well as a prolonged delivery at the biological level. Finally, an in situ infrared spectroscopy study confirms not only the coordination of NO over the Lewis acid sites and the stronger binding of NO on the additional iron(II) sites, providing further insights over the partial release of NO only in the presence of water at room temperature.

  3. Review of laser produced multi-keV X-ray sources from metallic foils, cylinders with liner, and low density aerogels

    NASA Astrophysics Data System (ADS)

    Girard, Frédéric

    2016-04-01

    Experimental results obtained within the last fifteen years on multi-keV X-ray sources irradiated with nanosecond scale pulse duration 3ω laser light at TW power levels by CEA and collaborators are discussed in this review paper. Experiments were carried out on OMEGA and GEKKO XII laser facilities where emitting materials in the 5-10 keV multi-keV energy range are intermediate Z value metals from titanium to germanium. Results focused on conversion efficiency improvement by a factor of 2 when an underdense plasma is created using a laser pre-pulse on a metallic foil, which is then heated by a second laser pulse delayed in time. Metal coated inner surface walls of plastic cylindrical tube ablated by laser beam impacts showed that plasma confinement doubles X-ray emission duration as it gives adequate plasma conditions (electron temperature and density) over a long period of time. Low-density aerogels (doped with metal atoms uniformly distributed throughout their volume or metal oxides) contained in a plastic cylinder have been developed and their results are comparable to gas targets. A hybrid target concept consisting of a thin metal foil placed at the end of a cylinder filled with low density aerogel has emerged as it could collect benefits from pre-exploded thin foils, efficient laser absorption in aerogel, and confinement by cylinder walls. All target geometry performances are relatively close together at a given photon energy and mainly depend on laser irradiation condition optimizations. Results are compared with gas target performances from recent NIF experiments allowing high electron temperatures over large dimension low density plasmas, which are the principal parameters for efficient multi-keV X-ray production.

  4. Extent of fungal growth on fiberglass duct liners with and without biocides under challenging environmental conditions.

    PubMed

    Samimi, Behzad S; Ross, Kristen

    2003-03-01

    Eight brands of fiberglass duct liners, including three that contained biocides, were exposed to challenging environmental conditions that would promote fungal growth. Twenty-four rectangular sheet metal ducts in three groups of eight ducts per group were lined with the eight selected liners. Each group of ducts was exposed to one of the three test conditions within an environmental chamber for a period of 15 days. These conditions were a) 75 percent RH, b) 75 percent RH plus water spray, c) 75 percent RH plus dry nutrient, and d) 75 percent RH plus water plus nutrient. Viable spores of Aspergillus niger were aerosolized into each duct as seed. On the 16th day, air and surface samples for fungal spores were collected from inside ducts. The results of air sampling using N6 sampler and visual inspection indicated that two out of three biocide-containing liners, Permacote and Toughgard, inhibited fungal growth but only under condition A. The third biocide-containing liner, Aeroflex Plus, was effective even when it was wet (conditions A and B). All three biocide-containing liners failed to inhibit fungal growth under conditions C and D. Among the five other types of liners that did not contain biocides, ATCO Flex with a smooth Mylar coating was more preferable, exhibiting lower fungal activity during conditions A, B, and C. All liners failed under condition D when nutrient and water were added together. Surface sampling using adhesive tape failed to produce representative results, apparently due to rough/porous surface of duct liners. It was concluded that duct liners with biocide treatment could be less promoting to microbial growth under high humidity as long as their surfaces remain clean and water-free. A liner with an impermeable and smooth surface seems to be less subject to microbial growth under most conditions than biocide-containing liners having porous and/or rough surfaces. PMID:12573965

  5. Advanced Turbofan Duct Liner Concepts

    NASA Technical Reports Server (NTRS)

    Bielak, Gerald W.; Premo, John W.; Hersh, Alan S.

    1999-01-01

    The Advanced Subsonic Technology Noise Reduction Program goal is to reduce aircraft noise by 10 EPNdB by the year 2000 relative, to 1992 technology. The improvement goal for nacelle attenuation is 25% relative to 1992 technology by 1997 and 50% by 2000. The Advanced Turbofan Duct Liner Concepts Task work by Boeing presented in this document was in support of these goals. The basis for the technical approach was a Boeing study conducted in 1993-94 under NASA/FAA contract NAS1-19349, Task 6, investigating broadband acoustic liner concepts. As a result of this work, it was recommended that linear double layer, linear and perforate triple layer, parallel element, and bulk absorber liners be further investigated to improve nacelle attenuations. NASA LaRC also suggested that "adaptive" liner concepts that would allow "in-situ" acoustic impedance control also be considered. As a result, bias flow and high-temperature liner concepts were also added to the investigation. The major conclusion from the above studies is that improvements in nacelle liner average acoustic impedance characteristics alone will not result in 25% increased nacelle noise reduction relative to 1992 technology. Nacelle design advancements currently being developed by Boeing are expected to add 20-40% more acoustic lining to hardwall regions in current inlets, which is predicted to result in and additional 40-80% attenuation improvement. Similar advancements are expected to allow 10-30% more acoustic lining in current fan ducts with 10-30% more attenuation expected. In addition, Boeing is currently developing a scarf inlet concept which is expected to give an additional 40-80% attenuation improvement for equivalent lining areas.

  6. Preventing Cracks in Silicon-Reactor Liners

    NASA Technical Reports Server (NTRS)

    Lutwack, R.

    1987-01-01

    Correct placement helps prevent contamination while eliminating crack-causing deposits. Repositioning quartz liner in silicon fluidized-bed reactor prevents cracking of liner when cools. Liner protects stainless-steel walls of reactor from abrasion by particles in fluidized bed. Prevents contamination of newly formed silicon by material abraded from wall and ensures high-quality product.

  7. Metal binding properties and structure of a type III metallothionein from the metal hyperaccumulator plant Noccaea caerulescens.

    PubMed

    Fernandez, Lucia Rubio; Vandenbussche, Guy; Roosens, Nancy; Govaerts, Cédric; Goormaghtigh, Erik; Verbruggen, Nathalie

    2012-09-01

    Metallothioneins (MT) are low molecular weight proteins with cysteine-rich sequences that bind heavy metals with remarkably high affinities. Plant MTs differ from animal ones by a peculiar amino acid sequence organization consisting of two short Cys-rich terminal domains (containing from 4 to 8 Cys each) linked by a Cys free region of about 30 residues. In contrast with the current knowledge on the 3D structure of animal MTs, there is a striking lack of structural data on plant MTs. We have expressed and purified a type III MT from Noccaea caerulescens (previously Thlaspi caerulescens). This protein is able to bind a variety of cations including Cd(2+), Cu(2+), Zn(2+) and Pb(2+), with different stoichiometries as shown by mass spectrometry. The protein displays a complete absence of periodic secondary structures as measured by far-UV circular dichroism, infrared spectroscopy and hydrogen/deuterium exchange kinetics. When attached onto a BIA-ATR biosensor, no significant structural change was observed upon removing the metal ions. PMID:22668884

  8. Beryllium liner implosion experiments on the Z accelerator in preparation for Magnetized Liner Inertial Fusion (MagLIF)*

    NASA Astrophysics Data System (ADS)

    McBride, Ryan D.

    2012-10-01

    Magnetized Liner Inertial Fusion (MagLIF) [1] is a concept that involves using a pulsed electrical current to implode an initially-solid, cylindrical metal tube (liner) filled with preheated and magnetized fusion fuel. One- and two-dimensional simulations predict that if sufficient liner integrity can be maintained throughout the implosion, then significant fusion yield (>100 kJ) is possible on the 25-MA, 100-ns Z accelerator. The greatest threat to the liner integrity is the Magneto-Rayleigh-Taylor (MRT) instability, which first develops on the outer liner surface, and then works its way inward toward the inner surface throughout the implosion. Two-dimensional simulations predict that a thick liner, with Router/δR=6, should be robust enough to keep the MRT instability from overly disrupting the fusion burn at stagnation. This talk will present the first experiments designed to study a thick, MagLIF-relevant liner implosion through to stagnation on Z [2]. The use of beryllium for the liner material enabled us to obtain penetrating monochromatic (6151±0.5 eV) radiographs that reveal information about the entire volume of the imploding liner. This talk will also discuss experiments that investigated Z's pulse-shaping capabilities to either shock- or shocklessly-compress the imploding liners [3], as well as our most recent experiments that used 2-micron-thick aluminum sleeves to provide high-contrast tracers for the positions and states of the inner surfaces of the imploding beryllium liners. The radiography data to be presented provide stringent constraints on the simulation tools used by the broader high energy density physics and inertial confinement fusion communities, where quantitative areal density measurements, particularly of convergent fusion targets, are relatively scarce. We will also present power-flow tests of the MagLIF load hardware as well as new micro-B-dot measurements of the azimuthal drive magnetic field that penetrates the initially vacuum

  9. Design and preliminary results of a semitranspiration cooled (Lamilloy) liner for a high-pressure high-temperature combustor

    NASA Technical Reports Server (NTRS)

    Wear, J. D.; Trout, A. M.; Smith, J. M.; Jones, R. E.

    1978-01-01

    A Lamilloy combustor liner was designed, fabricated and tested in a combustor at pressures up to 8 atmospheres. The liner was fabricated of a three layer Lamilloy structure and designed to replace a conventional step louver liner. The liner is to be used in a combustor that provides hot gases to a turbine cooling test facility at pressures up to 40 atmospheres. The Lamilloy liner was tested extensively at lower pressures and demonstrated lower metal temperatures than the conventional liner, while at the same time requiring about 40 percent less cooling air flow. Tests conducted at combustor exit temperatures in excess of 2200 K have not indicated any cooling or durability problems with the Lamilloy linear.

  10. Dual emission from an ortho-metalated Ir(III) complex

    SciTech Connect

    King, K.A.; Watts, R.J.

    1987-03-04

    Several complexes of Ir(III) containing both the bidentate N-coordinating ligand 2,2'-bipyridine (bpy) and the N,C-orthometalating ligand 2-phenylpyridine (ppy) have recently been prepared; these include the two species Ir(ppy)/sub 2/(bpy)/sup +/ (A) and Ir(ppy)(bpy)/sub 2//sup 2 +/ (B). The former was prepared from the dichloro-bridged dimer, (Ir(ppy)/sub 2/Cl)/sub 2/, by modification of the procedure of Nonoyama while the latter was obtained by reaction of cis-(Ir(bpy)/sub 2/(OSO/sub 2/CF/sub 3/)/sub 2/) (CF/sub 3/SO/sub 3/) with ppy in refluxing 2-ethoxyethanol. The purity of the complexes was monitored with thin-layer chromatography using silica gel plates and 1:1:1 acetone/methanol/water mixtures for elution. Samples of the complexes used in these studies showed only one component in thin-layer chromatography. While only one isomer of B is possible, there are three possible isomers of A. Data from /sup 1/H and /sup 13/C NMR experiments indicate that A has C/sub 2/ symmetry. The NMR spectrum indicates, as does thin-layer chromatography, that only a single isomer of A is present with no detectable impurities due to a mixture of isomers. While X-ray structural data for A are lacking, structural data for related complexes suggest that A is the isomer with cisoid metal-carbon bonds and bpy metal-nitrogen bonds transoid to the metal-carbon bonds and bpy metal-nitrogen bonds transoid to the metal-carbon bonds. These species were prepared in order to probe further the effects of metal-carbon bonding on energy-transfer processes and electron-transfer reactions of metal complexes. Emission spectroscopic studies reported here reveal unusual and distinct intramolecular energy-transfer behavior in these complexes. Whereas dual emission from the former is observed in glasses at 77 K, a single emission is observed in the latter.

  11. Photo-oxidation of Sb(III) in the seawater by marine phytoplankton-transition metals-light system.

    PubMed

    Li, Shun-Xing; Zheng, Feng-Ying; Hong, Hua-Sheng; Deng, Nan-Sheng; Zhou, Xia-Yi

    2006-11-01

    The photo-oxidation of Sb(III) to Sb(V) by marine microalgae (diatom, green and red algae) with or without the presence of transition metals (Fe(III), Cu(II) and Mn(II)). The influence of marine phytoplankton on the photochemistry of antimony was confirmed for the first time. The conversion ratio of Sb(III) to Sb(V) increased with increasing algae concentration and irradiation time. Different species of marine phytoplankton were found to have different photo-oxidizing abilities. The photochemical redox of transition metals could induce the species transformation of antimony. After photo-induced oxidation by marine phytoplankton and transition metals, the ratio of Sb(V) to Sb(III) was in the range of 1.07-5.48 for six algae (Tetraselmis levis, Chlorella autotrophica, Nannochloropsis sp., Tetraselmis subcordiformis, Phaeodactylum tricornutum, and Porphyridium purpureum), and only 0.92 for Dunaliella salina. The distribution of antimony in the sunlit surface seawater was greatly affected by combined effects of marine phytoplankton (main contributor) and transition metals; both synergistic and antagonistic effects were observed. The results provided further insights into the distribution of Sb(III) and Sb(V) and the biogeochemical cycle of antimony, and have significant implications for the risk assessment of antimony in the sunlit surface seawater.

  12. Trabecular Metal Augments for the Management of Paprosky Type III Defects Without Pelvic Discontinuity.

    PubMed

    Grappiolo, Guido; Loppini, Mattia; Longo, Umile Giuseppe; Traverso, Francesco; Mazziotta, Giuseppe; Denaro, Vincenzo

    2015-06-01

    Fifty-five hips undergoing acetabular reconstruction with trabecular metal (TM)-coated cup and TM augments were reviewed at an average follow up of 53.7 months (36-91). Bony defects were Paprosky type IIIA in 42 and type IIIB without pelvic discontinuity in 13 hips. The average HHS increased from 40 (27-52) preoperatively to 90.5 (61-100) postoperatively (P<0.0001). Four (7.3%) of 55 hips underwent acetabular components revision: three cases of loosening (5.4%), and one of recurrent instability (1.8%) were reported. Survival rate at 2 and 5 years was 96.4% and 92.8%. In conclusion, the use of TM-coated cups and augments could be considered an effective management of Paprosky type III defects without pelvic discontinuity providing good clinical and radiographic outcomes in the mid term.

  13. Characterization of EPICOR II Prefilter Liner 16

    SciTech Connect

    Yesso, J D; Pasupathi, V; Lowry, L

    1982-08-01

    As part of the overall TMI-2 Information and Examination Program, EPICOR II Prefilter Liner 16 was examined to provide information to aid in the development of technology for safely processing highly loaded ion-exchange media. The characterization program included sampling and analyses of the liner contents, including ion-exchange media, liquids and gases, as well as examinations of the liner interior and exterior. This report details the handling of the liner, sampling and analysis of the contents, and the examinations of the liner.

  14. Segmented ceramic liner for induction furnaces

    DOEpatents

    Gorin, A.H.; Holcombe, C.E.

    1994-07-26

    A non-fibrous ceramic liner for induction furnaces is provided by vertically stackable ring-shaped liner segments made of ceramic material in a light-weight cellular form. The liner segments can each be fabricated as a single unit or from a plurality of arcuate segments joined together by an interlocking mechanism. Also, the liner segments can be formed of a single ceramic material or can be constructed of multiple concentric layers with the layers being of different ceramic materials and/or cellular forms. Thermomechanically damaged liner segments are selectively replaceable in the furnace. 5 figs.

  15. Segmented ceramic liner for induction furnaces

    DOEpatents

    Gorin, Andrew H.; Holcombe, Cressie E.

    1994-01-01

    A non-fibrous ceramic liner for induction furnaces is provided by vertically stackable ring-shaped liner segments made of ceramic material in a light-weight cellular form. The liner segments can each be fabricated as a single unit or from a plurality of arcuate segments joined together by an interlocking mechanism. Also, the liner segments can be formed of a single ceramic material or can be constructed of multiple concentric layers with the layers being of different ceramic materials and/or cellular forms. Thermomechanically damaged liner segments are selectively replaceable in the furnace.

  16. Novel Materials for Prosthetic Liners

    NASA Technical Reports Server (NTRS)

    Ragolta, Carolina I.; Morford, Megan

    2011-01-01

    Existing materials for prosthetic liners tend to be thick and airtight, causing perspiration to accumulate inside the liner and potentially causing infection and injury that reduce quality of life. The purpose of this project was to examine the suitability of aerogel for prosthetic liner applications. Three tests were performed on several types of aerogel to assess the properties of each material. Moisture vapor permeability was tested by incubating four aerogel varieties with an artificial sweat solution at 37.0 C and less than 20% relative humidity for 24 hours. Two aerogel varieties were eliminated from the study due to difficulties in handling the material, and further testing proceeded with Pyrogel in 2.0 and 6.0 mm thicknesses. Force distribution was tested by compressing samples under a load of 4448 N at a rate of 2.5 mm/min. Biofilm formation was tested in a high-shear CDC Biofilm Reactor. Results showed that 2.0 mm Pyrogel blanket allowed 55.7 plus or minus 28.7% of an artificial sweat solution to transpire, and 35.5 plus or minus 27.8% transpired through 6.0 mm Pyrogel blanket. Samples also outperformed the load-bearing capabilities of existing liner materials. No statistically significant difference was found between the two Pyrogel thicknesses for either moisture vapor permeability or force distribution. In addition, biofilm formation results showed no change between the two Pyrogel thicknesses. The breathability and load bearing properties of aerogel make it a suitable material for application to prosthetic liners.

  17. THE MOST METAL-POOR STARS. III. THE METALLICITY DISTRIBUTION FUNCTION AND CARBON-ENHANCED METAL-POOR FRACTION , ,

    SciTech Connect

    Yong, David; Norris, John E.; Bessell, M. S.; Asplund, M.; Christlieb, N.; Beers, Timothy C.; Barklem, P. S.; Frebel, Anna; Ryan, S. G. E-mail: jen@mso.anu.edu.au E-mail: martin@mso.anu.edu.au E-mail: beers@pa.msu.edu E-mail: afrebel@mit.edu

    2013-01-01

    We examine the metallicity distribution function (MDF) and fraction of carbon-enhanced metal-poor (CEMP) stars in a sample that includes 86 stars with [Fe/H] {<=} -3.0, based on high-resolution, high signal-to-noise spectroscopy, of which some 32 objects lie below [Fe/H] = -3.5. After accounting for the completeness function, the 'corrected' MDF does not exhibit the sudden drop at [Fe/H] = -3.6 that was found in recent samples of dwarfs and giants from the Hamburg/ESO survey. Rather, the MDF decreases smoothly down to [Fe/H] = -4.1. Similar results are obtained from the 'raw' MDF. We find that the fraction of CEMP objects below [Fe/H] = -3.0 is 23% {+-} 6% and 32% {+-} 8% when adopting the Beers and Christlieb and Aoki et al. CEMP definitions, respectively. The former value is in fair agreement with some previous measurements, which adopt the Beers and Christlieb criterion.

  18. Ceramic composite liner material for gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Ercegovic, D. B.; Walker, C. L.; Norgren, C. T.

    1984-01-01

    Advanced commercial and military gas turbine engines may operate at combustor outlet temperatures in excess of 1920 K (3000 F). At these temperatures combustors liners experience extreme convective and radiative heat fluxes. The ability of a plasma sprayed ceramic coating to reduce liner metal temperature has been recognized. However, the brittleness of the ceramic layer and the difference in thermal expansion with the metal substrate has caused cracking, spalling and some separation of the ceramic coating. Research directed at turbine tip seals (or shrouds) has shown the advantage of applying the ceramic to a compliant metal pad. This paper discusses recent studies of applying ceramics to combustor liners in which yttria stabilized zirconia plasma sprayed on compliant metal substrates which were exposed to near stoichiometric combustion, presents performance and durability results, and describes a conceptual design for an advanced, small gas turbine combustor. Test specimens were convectively cooled or convective-transpiration cooled and were evaluated in a 10 cm square flame tube combustor at inlet air temperatures of 533 K (500 F) and at a pressure of 0.5 MPa (75 psia). The ceramics were exposed to flame temperatures in excess of 2000 K (3320 F). Results appear very promising with all 30 specimens surviving a screening test and one of two specimens surviving a cyclic durability test.

  19. Metal interferences and their removal prior to the determination of As(T) and As(III) in acid mine waters by hydride generation atomic absorption spectrometry

    USGS Publications Warehouse

    McCleskey, R. Blaine; Nordstrom, D. Kirk; Ball, James W.

    2003-01-01

    Hydride generation atomic absorption spectrometry (HGAAS) is a sensitive and selective method for the determination of total arsenic (arsenic(III) plus arsenic(V)) and arsenic(III); however, it is subject to metal interferences for acid mine waters. Sodium borohydride is used to produce arsine gas, but high metal concentrations can suppress arsine production. This report investigates interferences of sixteen metal species including aluminum, antimony(III), antimony(V), cadmium, chromium(III), chromium(IV), cobalt, copper(II), iron(III), iron(II), lead, manganese, nickel, selenium(IV), selenium(VI), and zinc ranging in concentration from 0 to 1,000 milligrams per liter and offers a method for removing interfering metal cations with cation exchange resin. The degree of interference for each metal without cation-exchange on the determination of total arsenic and arsenic(III) was evaluated by spiking synthetic samples containing arsenic(III) and arsenic(V) with the potential interfering metal. Total arsenic recoveries ranged from 92 to 102 percent for all metals tested except antimony(III) and antimony(V) which suppressed arsine formation when the antimony(III)/total arsenic molar ratio exceeded 4 or the antimony(V)/total arsenic molar ratio exceeded 2. Arsenic(III) recoveries for samples spiked with aluminum, chromium(III), cobalt, iron(II), lead, manganese, nickel, selenium(VI), and zinc ranged from 84 to 107 percent over the entire concentration range tested. Low arsenic(III) recoveries occurred when the molar ratios of metals to arsenic(III) were copper greater than 120, iron(III) greater than 70, chromium(VI) greater than 2, cadmium greater than 800, antimony(III) greater than 3, antimony(V) greater than 12, or selenium(IV) greater than 1. Low recoveries result when interfering metals compete for available sodium borohydride, causing incomplete arsine production, or when the interfering metal oxidizes arsenic(III). Separation of interfering metal cations using

  20. Liners for ion transport membrane systems

    SciTech Connect

    Carolan, Michael Francis; Miller, Christopher Francis

    2010-08-10

    Ion transport membrane system comprising (a) a pressure vessel comprising an interior, an exterior, an inlet, an inlet conduit, an outlet, and an outlet conduit; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein the inlet and the outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; (c) a gas manifold having an interior surface wherein the gas manifold is in flow communication with the interior region of each of the planar ion transport membrane modules and with the exterior of the pressure vessel; and (d) a liner disposed within any of the inlet conduit, the outlet conduit, and the interior surface of the gas manifold.

  1. Trace elements and heavy metals in hair of stage III breast cancer patients.

    PubMed

    Benderli Cihan, Yasemin; Sözen, Selim; Oztürk Yıldırım, Sema

    2011-12-01

    This prospective study was designed to compare the hair levels of 36 elements in 52 patients with stage III breast cancer to those of an equal number of healthy individuals. Principal component and cluster analysis were used for source of identification and apportionment of heavy metals and trace elements in these two groups. A higher average level of iron was found in samples from patients while controls had higher levels of calcium. Both patients and controls had elevated levels of tin, magnesium, zinc, and sodium. Almost all element values in cancer patients showed higher dispersion and asymmetry than in healthy controls. Between the two groups, there were statistically significant differences in the concentrations of silver, arsenic, gold, boron, barium, beryllium, calcium, cadmium, cerium, cobalt, cesium, gadolinium, manganese, nickel, lead, antimony, scandium, selenium, and zinc (p < 0.05). Strong positive correlations were found between lead and gold (r = 0.785) in the cancer group and between palladium and cobalt (r = 0.945) in the healthy individuals. Our results show that there are distinct patterns of heavy metals and trace elements in the hair of breast cancer patients in comparison to healthy controls. These results could be of significance in the diagnosis of breast cancer. PMID:21660533

  2. Deoxidation of (001) III-V semiconductors in metal-organic vapour phase epitaxy

    NASA Astrophysics Data System (ADS)

    Kaspari, Christian; Pristovsek, Markus; Richter, Wolfgang

    2016-08-01

    We studied the deoxidation of several (001) III-V semiconductors in metal-organic vapour phase epitaxy using in-situ reflectance anisotropy spectroscopy and in-situ spectroscopic ellipsometry. The oxide desorption started as soon as kBT reaches 1/15th of the bond strength of the crystal if there is hydrogen or group V precursor present. The oxide thickness decreases first and afterwards the surface slowly reconstructs. At a constant temperature the oxide thickness decreased according to a second order reaction. We found two processes on InAs and GaAs, but only a single one on InP. The activation energy for the removal of epi-ready oxide under group V flux was 0.64 eV, 1.1 eV, and 1.3 eV on InAs, GaAs, and InP, respectively. The end of oxide desorption is determined by the removal of the last metal rich oxides, at temperatures of 500 °C for InAs/InP and 600 °C for GaAs/GaP.

  3. High-Yield Magnetized Liner Fusion Explosions and Blast Mitigation

    NASA Astrophysics Data System (ADS)

    Slutz, Stephen; Vesey, Roger; Cuneo, Michael

    2011-10-01

    Cylindrical liner implosions with preheated and magnetized deuterium-tritium (DT) are predicted to reach fusion conditions on present pulsed power machines [S.A. Slutz et al Phys. Plasmas 17, 056303 (2010)]. We present simulations indicating that high yields (1-10 GJ) and gains (100-1000) may be possible at currents of about 60-70 MA if a cryogenic layer of solid DT is provided on the inside surface of the metal liner. A hot spot is formed from the central preheated magnetized low-density gas and a burn wave propagates radially into the surrounding cold dense fuel. These yields and gains are more than adequate for inertial fusion energy. However, the pulsed-power driver must be protected from the blast of these high-yield explosions. Numerical simulations are presented which show that the blast can be deflected and the fusion neutrons absorbed by a blanket that partially surrounds the liner. Thus a modest length transmission line can be used to deliver power to the liner. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  4. Polymer-cobalt(III) complexes: structural analysis of metal chelates on DNA interaction and comparative cytotoxic activity.

    PubMed

    Nehru, Selvan; Arunachalam, Sankaralingam; Arun, Renganathan; Premkumar, Kumpati

    2014-01-01

    A new series of pendant-type polymer-cobalt(III) complexes, [Co(LL)2(BPEI)Cl](2+), (where BPEI = branched polyethyleneimine, LL = dipyrido[3,2-a:2',3'-c](6,7,8,9-tetrahydro)phenazine (dpqc), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq) and imidazo[4,5-f]1,10-phenanthroline (ip)) each with three different degrees of coordination have been synthesized and characterized. Studies to know the mode and strength of interaction between these polymer-metal complexes and calf thymus DNA have been performed by UV-Visible absorption and emission techniques. Among these series, each polymer metal complex having higher binding strength with DNA has been selected to test against human cancer/normal cell lines. On the basis of these spectral studies, it is proposed that our polymer-metal complexes bind with DNA mainly through intercalation along with some electrostatic binding. The order of binding strength for the complexes with ligand, dpqc > dpq > ip. The analysis of the results suggests that polymer-cobalt(III) complexes with higher degree of coordination effectively binds with DNA due to the presence of large number of positively charged cobalt(III) chelates in the polymer chain which cooperatively act to increase the overall binding strength. These polymer-cobalt(III) complexes with hydrophobic ligands around the cobalt(III) metal centre favour the base stacking interactions via intercalation. All the complexes show very good anticancer activities and increasing of binding strength results in higher inhibition value. The polymer-cobalt(III) complex with dpqc ligand possess two fold increased anticancer activity when compared to complexes with other ligands against MCF-7 cells. Besides, the complexes were insensitive towards the growth of normal cells (HEK-293) at the IC50 concentration.

  5. Magnetized Target Fusion Driven by Plasma Liners

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Eskridge, Richard; Smith, James; Lee, Michael; Richeson, Jeff; Schmidt, George; Knapp, Charles E.; Kirkpatrick, Ronald C.; Turchi, Peter J.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Magnetized target fusion (MTF) attempts to combine the favorable attributes of magnetic confinement fusion (MCF) for energy confinement with the attributes of inertial confinement fusion (ICF) for efficient compression heating and wall-free containment of the fusing plasma. It uses a material liner to compress and contain a magnetized plasma. For practical applications, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC). For the successful implementation of the scheme, plasma jets of the requisite momentum flux density need to be produced. Their transport over sufficiently large distances (a few meters) needs to be assured. When they collide and merge into a liner, relative differences in velocity, density and temperature of the jets could give rise to instabilities in the development of the liner. Variation in the jet properties must be controlled to ensure that the growth rate of the instabilities are not significant over the time scale of the liner formation before engaging with the target plasma. On impact with the target plasma, some plasma interpenetration might occur between the liner and the target. The operating parameter space needs to be identified to ensure that a reasonably robust and conducting contact surface is formed between the liner and the target. A mismatch in the "impedance" between the liner and the target plasma could give rise to undesirable shock heating of the liner leading to increased entropy (thermal losses) in the liner. Any irregularities in the liner will accentuate the Rayleigh-Taylor instabilities during the compression of the target plasma by the liner.

  6. Draft Genome Sequence of Micrococcus sp. Strain MS-AsIII-49, an Arsenate-Reducing Isolate from Tropical Metal-Rich Sediment

    PubMed Central

    Costa, Patrícia S.; Tschoeke, Diogo A.; Silva, Bruno S. O.; Thompson, Fabiano; Reis, Mariana P.; Chartone-Souza, Edmar

    2015-01-01

    Micrococcus sp. strain MS-AsIII-49, which was isolated from a tropical metal-polluted stream sediment in Brazil, has the ability to reduce AsV to AsIII. Analysis of its draft genome revealed 186 contigs with a total size of 2,440,924 bp encoding several metal resistance genes. PMID:25883272

  7. Elastic Plastic Fracture Analysis of an Aluminum COPV Liner

    NASA Technical Reports Server (NTRS)

    Forth, Scott; Gregg, Bradley; Bailey, Nathaniel

    2012-01-01

    Onboard any space-launch vehicle, composite over-wrapped pressure vessels (COPVs) may be utilized by propulsion or environmental control systems. The failure of a COPV has the potential to be catastrophic, resulting in the loss of vehicle, crew or mission. The latest COPV designs have reduced the wall-thickness of the metallic liner to the point where the material strains plastically during operation. At this time, the only method to determine the damage tolerance lifetime (safe-life) of a plastically responding metallic liner is through full-scale COPV testing. Conducting tests costs substantially more and can be far more time consuming than performing an analysis. As a result of this cost, there is a need to establish a qualifying process through the use of a crack growth analysis tool. This paper will discuss fracture analyses of plastically responding metallic liners in COPVs. Uni-axial strain tests have been completed on laboratory specimens to collect elastic-plastic crack growth data. This data has been modeled with the crack growth analysis tool, NASGRO 6.20 to predict the response of laboratory specimens and subsequently the complexity of a COPV.

  8. Energy transfer through a multi-layer liner for shaped charges

    DOEpatents

    Skolnick, Saul; Goodman, Albert

    1985-01-01

    This invention relates to the determination of parameters for selecting materials for use as liners in shaped charges to transfer the greatest amount of energy to the explosive jet. Multi-layer liners constructed of metal in shaped charges for oil well perforators or other applications are selected in accordance with the invention to maximize the penetrating effect of the explosive jet by reference to four parameters: (1) Adjusting the explosive charge to liner mass ratio to achieve a balance between the amount of explosive used in a shaped charge and the areal density of the liner material; (2) Adjusting the ductility of each layer of a multi-layer liner to enhance the formation of a longer energy jet; (3) Buffering the intermediate layers of a multi-layer liner by varying the properties of each layer, e.g., composition, thickness, ductility, acoustic impedance and areal density, to protect the final inside layer of high density material from shattering upon impact of the explosive force and, instead, flow smoothly into a jet; and (4) Adjusting the impedance of the layers in a liner to enhance the transmission and reduce the reflection of explosive energy across the interface between layers.

  9. A Finite Element Theory for Predicting the Attenuation of Extended-Reacting Liners

    NASA Technical Reports Server (NTRS)

    Watson, W. R.; Jones, M. G.

    2009-01-01

    A non-modal finite element theory for predicting the attenuation of an extended-reacting liner containing a porous facesheet and located in a no-flow duct is presented. The mathematical approach is to solve separate wave equations in the liner and duct airway and to couple these two solutions by invoking kinematic constraints at the facesheet that are consistent with a continuum theory of fluid motion. Given the liner intrinsic properties, a weak Galerkin finite element formulation with cubic polynomial basis functions is used as the basis for generating a discrete system of acoustic equations that are solved to obtain the coupled acoustic field. A state-of-the-art, asymmetric, parallel, sparse equation solver is implemented that allows tens of thousands of grid points to be analyzed. A grid refinement study is presented to show that the predicted attenuation converges. Excellent comparison of the numerically predicted attenuation to that of a mode theory (using a Haynes 25 metal foam liner) is used to validate the computational approach. Simulations are also presented for fifteen porous plate, extended-reacting liners. The construction of some of the porous plate liners suggest that they should behave as resonant liners while the construction of others suggest that they should behave as broadband attenuators. In each case the finite element theory is observed to predict the proper attenuation trend.

  10. Reciprocal engine with floating liner

    SciTech Connect

    Paul, M.A.; Paul, A.

    1989-06-27

    An internal combustion engine with a heat recovery system is described comprising: a cylinder with a cylinder wall; a piston with a piston head, the piston being reciprocally displaceable in the cylinder; a fuel injection means with fuel connected to the cylinder; and, an air intake passage and an exhaust passage connected to the cylinder, such that air is delivered to the cylinder, compressed by the piston, and fuel from the fuel injection means is delivered to the cylinder and combusted in a working chamber; wherein the heat recovery system includes an air-porous, heat-resistant tubular liner suspended in the cylinder and displaced from the wall of the cylinder, the piston having a deep groove with inner and outer walls in the head of the piston into which the liner is received when the piston is displaced compressing the air, the liner being spaced from the inner and outer walls of the groove such that three insulating zones are provided between combustion gases in the cylinder and the cylinder wall during displacement of the piston.

  11. Three new europium(III) methanetriacetate metal-organic frameworks: the influence of synthesis on the product topology.

    PubMed

    Cañadillas-Delgado, Laura; Fabelo, Oscar; Pasán, Jorge; Déniz, Mariadel; Martínez-Benito, Carla; Díaz-Gallifa, Pau; Martín, Tomás; Ruiz-Pérez, Catalina

    2014-02-01

    Three new metal-organic framework structures containing Eu(III) and the little explored methanetriacetate (C7H7O6(3-), mta(3-)) ligand have been synthesized. Gel synthesis yields a two-dimensional framework with the formula [Eu(mta)(H2O)3]n·2nH2O, (I), while two polymorphs of the three-dimensional framework material [Eu(mta)(H2O)]n·nH2O, (II) and (III), are obtained through hydrothermal synthesis at either 423 or 443 K. Compounds (I) and (II) are isomorphous with previously reported Gd(III) compounds, but compound (III) constitutes a new phase. Compound (I) can be described in terms of dinuclear [Eu2(H2O)4](6+) units bonded through mta(3-) ligands to form a two-dimensional framework with topology corresponding to a (6,3)-connected binodal (4(3))(4(6)6(6)8(3))-kgd net, where the dinuclear [Eu2(H2O)4](6+) units are considered as a single node. Compounds (II) and (III) have distinct three-dimensional topologies, namely a (4(12)6(3))(4(9)6(6))-nia net for (II) and a (4(10)6(5))(4(11)6(4))-K2O2; 36641 net for (III). The crystal density of (III) is greater than that of (II), consistent with the increase of temperature, and thereby autogeneous pressure, in the hydrothermal synthesis.

  12. Solvent effects on metal-to-ligand charge-transfer bands in ortho-metalated complexes of iridium(III): Estimates of transition dipole moments

    SciTech Connect

    Wilde, A.P.; Watts, R.J. )

    1991-01-24

    Shifts in the absorption and emission maxima of several ortho-metalated complexes of Ir(III) in a series of solvents are reported. These complexes contain combinations of the ortho-metalating ligands 2-phenylpyridine or benzo(h)quinoline and the chelating ligands 2,2{prime}-bipyridine or 1,10-phenanthroline bonded to the Ir(III). The solvent-induced shifts are interpreted in terms of theoretical treatments due to McRae and to Marcus. Each of these treatments leads to estimates of transition dipoles associated with absorption, and the sign and magnitude of the transition dipole indicate that the direction of the excited-state dipole is opposite that of the ground-state dipole. This result is consistent with prior assignments of the absorption band to a metal-to-ligand charge-transfer excited state associated with the chelating ligand.

  13. Thermal Hazard Evaluation of Cumene Hydroperoxide-Metal Ion Mixture Using DSC, TAM III, and GC/MS.

    PubMed

    You, Mei-Li

    2016-01-01

    Cumene hydroperoxide (CHP) is widely used in chemical processes, mainly as an initiator for the polymerization of acrylonitrile-butadiene-styrene. It is a typical organic peroxide and an explosive substance. It is susceptible to thermal decomposition and is readily affected by contamination; moreover, it has high thermal sensitivity. The reactor tank, transit storage vessel, and pipeline used for manufacturing and transporting this substance are made of metal. Metal containers used in chemical processes can be damaged through aging, wear, erosion, and corrosion; furthermore, the containers might release metal ions. In a metal pipeline, CHP may cause incompatibility reactions because of catalyzed exothermic reactions. This paper discusses and elucidates the potential thermal hazard of a mixture of CHP and an incompatible material's metal ions. Differential scanning calorimetry (DSC) and thermal activity monitor III (TAM III) were employed to preliminarily explore and narrate the thermal hazard at the constant temperature environment. The substance was diluted and analyzed by using a gas chromatography spectrometer (GC) and gas chromatography/mass spectrometer (GC/MS) to determine the effect of thermal cracking and metal ions of CHP. The thermokinetic parameter values obtained from the experiments are discussed; the results can be used for designing an inherently safer process. As a result, the paper finds that the most hazards are in the reaction of CHP with Fe(2+). When the metal release is exothermic in advance, the system temperature increases, even leading to uncontrollable levels, and the process may slip out of control. PMID:27136518

  14. Thermal Hazard Evaluation of Cumene Hydroperoxide-Metal Ion Mixture Using DSC, TAM III, and GC/MS.

    PubMed

    You, Mei-Li

    2016-04-28

    Cumene hydroperoxide (CHP) is widely used in chemical processes, mainly as an initiator for the polymerization of acrylonitrile-butadiene-styrene. It is a typical organic peroxide and an explosive substance. It is susceptible to thermal decomposition and is readily affected by contamination; moreover, it has high thermal sensitivity. The reactor tank, transit storage vessel, and pipeline used for manufacturing and transporting this substance are made of metal. Metal containers used in chemical processes can be damaged through aging, wear, erosion, and corrosion; furthermore, the containers might release metal ions. In a metal pipeline, CHP may cause incompatibility reactions because of catalyzed exothermic reactions. This paper discusses and elucidates the potential thermal hazard of a mixture of CHP and an incompatible material's metal ions. Differential scanning calorimetry (DSC) and thermal activity monitor III (TAM III) were employed to preliminarily explore and narrate the thermal hazard at the constant temperature environment. The substance was diluted and analyzed by using a gas chromatography spectrometer (GC) and gas chromatography/mass spectrometer (GC/MS) to determine the effect of thermal cracking and metal ions of CHP. The thermokinetic parameter values obtained from the experiments are discussed; the results can be used for designing an inherently safer process. As a result, the paper finds that the most hazards are in the reaction of CHP with Fe(2+). When the metal release is exothermic in advance, the system temperature increases, even leading to uncontrollable levels, and the process may slip out of control.

  15. An extreme [O III] emitter at z = 3.2: a low metallicity Lyman continuum source

    NASA Astrophysics Data System (ADS)

    de Barros, S.; Vanzella, E.; Amorín, R.; Castellano, M.; Siana, B.; Grazian, A.; Suh, H.; Balestra, I.; Vignali, C.; Verhamme, A.; Zamorani, G.; Mignoli, M.; Hasinger, G.; Comastri, A.; Pentericci, L.; Pérez-Montero, E.; Fontana, A.; Giavalisco, M.; Gilli, R.

    2016-01-01

    Aims: Cosmic reionization is an important process occurring in the early epochs of the Universe. However, because of observational limitations due to the opacity of the intergalactic medium to Lyman continuum photons, the nature of ionizing sources is still not well constrained. While high-redshift star-forming galaxies are thought to be the main contributors to the ionizing background at z> 6, it is impossible to directly detect their ionizing emission. Therefore, looking at intermediate redshift analogues (z ~ 2-4) can provide useful hints about cosmic reionization. Methods: We investigate the physical properties of one of the best Lyman continuum emitter candidate at z = 3.212 found in the GOODS-S/CANDELS field with photometric coverage from the U to the MIPS 24 μm band and VIMOS/VLT and MOSFIRE/Keck spectroscopy. These observations allow us to derive physical properties such as stellar mass, star formation rate, age of the stellar population, dust attenuation, metallicity, and ionization parameter, and to determine how these parameters are related to the Lyman continuum emission. Results: Investigation of the UV spectrum confirms a direct spectroscopic detection of the Lyman continuum emission with S/N> 5. Non-zero Lyα flux at the systemic redshift and high Lyman-α escape fraction (fesc(Lyα) ≥ 0.78) suggest a low H i column density. The weak C and Si low-ionization absorption lines are also consistent with a low covering fraction along the line of sight. The subsolar abundances are consistent with a young and extreme starburst. The [O iii]λλ4959,5007+Hβ equivalent width (EW) is one of the largest reported for a galaxy at z> 3 (EW( [ O iii ] λλ4959,5007 + Hβ) ≃ 1600 Å, rest-frame; 6700 Å observed-frame) and the near-infrared spectrum shows that this is mainly due to an extremely strong [O iii] emission. The large observed [O iii]/[O ii] ratio (>10) and high ionization parameter are consistent with prediction from photoionization models in the

  16. Magnetized Target Fusion Driven by Plasma Liners

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Cassibry, Jason; Eskridge, Richard; Kirkpatrick, Ronald C.; Knapp, Charles E.; Lee, Michael; Martin, Adam; Smith, James; Wu, S. T.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    For practical applications of magnetized target fusion, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Quasi-spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a quasi-spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC). Theoretical analysis and computer modeling of the concept are presented. It is shown that, with the appropriate choice of the flow parameters in the liner and the target, the impact between the liner and the target plasma can be made to be shockless in the liner or to generate at most a very weak shock in the liner. Additional information is contained in the original extended abstract.

  17. Graphical Acoustic Liner Design and Analysis Tool

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M. (Inventor); Jones, Michael G. (Inventor)

    2016-01-01

    An interactive liner design and impedance modeling tool comprises software utilized to design acoustic liners for use in constrained spaces, both regularly and irregularly shaped. A graphical user interface allows the acoustic channel geometry to be drawn in a liner volume while the surface impedance calculations are updated and displayed in real-time. A one-dimensional transmission line model may be used as the basis for the impedance calculations.

  18. Effects of Liner Geometry on Acoustic Impedance

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Tracy, Maureen B.; Watson, Willie R.; Parrott, Tony L.

    2002-01-01

    Current aircraft engine nacelles typically contain acoustic liners consisting of perforated sheets bonded onto honeycomb cavities. Numerous models have been developed to predict the acoustic impedance of these liners in the presence of grazing flow, and to use that information with aeroacoustic propagation codes to assess nacelle liner noise suppression. Recent efforts have provided advances in impedance education methodologies that offer more accurate determinations of acoustic liner properties in the presence of grazing flow. The current report provides the results of a parametric study, in which a finite element method was used to assess the effects of variations of the following geometric parameters on liner impedance, with and without the presence of grazing flow: percent open area, sheet thickness, sheet thickness-to-hole diameter ratio and cavity depth. Normal incidence acoustic impedances were determined for eight acoustic liners, consisting of punched aluminum facesheets bonded to hexcell honeycomb cavities. Similar liners were tested in the NASA Langley Research Center grazing incidence tube to determine their response in the presence of grazing flow. The resultant data provide a quantitative assessment of the effects of these perforate, single-layer liner parameters on the acoustic impedance of the liner.

  19. Testing and Characterization of CMC Combustor Liners

    NASA Technical Reports Server (NTRS)

    Robinson, R. Craig; Verrilli, Michael J.

    2003-01-01

    Multiple combustor liner applications, both segmented and fully annular designs, have been configured for exposure in NASA's High Pressure Burner Rig (HPBR). The segmented liners were attached to the rig structure with SiC/SiC fasteners and exposed to simulated gas turbine conditions for nearly 200 hours. Test conditions included pressures of 6 atm., gas velocity of 42 m/s, and gas temperatures near 1450 C. The temperatures of both the cooled and combustion flow sides of the liners were measured using optical and contact measurement techniques. Minor weight loss was observed, but the liners remained structural sound, although damage was noted in some fasteners.

  20. Cracks in Flow Liners and Their Resolution

    NASA Technical Reports Server (NTRS)

    Harris, C. E.; Raju, I. S.

    2005-01-01

    Cracks were detected in flow liners at the gimbal joints in the LH2 feedlines of the space shuttle's main engines. The cracks initiated at defects in the drainage slots of the flow liners and grew due to high cycle fatigue. Fracture mechanics analyses were conducted to evaluate the life of the liners. These analyses yielded extremely short lives in the presence of small surface or corner cracks. A high fidelity detection method, edge replication, was used to detect the very small cracks. The detected cracks were removed by polishing and the surface quality of the slots was reestablished to improve life of the liners.

  1. Long Term Results of Liner Polyethylene Cementation Technique in Revision for Peri-acetabular Osteolysis.

    PubMed

    Rivkin, Gurion; Kandel, Leonid; Qutteineh, Bilal; Liebergall, Meir; Mattan, Yoav

    2015-06-01

    Patients with peri-acetabular osteolysis around a well fixed cementless acetabular component may be treated with liner exchange. When the locking mechanism is unreliable or unavailable, cementing the liner into the fixed acetabular component is a feasible option. The purpose of this study was to evaluate the clinical and radiographic long term results of this technique. Forty hip revisions with liner cementation in 37 patients were performed. The minimum follow up was 10 years. Modified Harris Hip Score and recent x rays were reviewed. Four hips were re-revised. Two patients were diagnosed with exacerbation of osteolysis but refused revision. Dislocation rate was relatively high (16%). Liner cementation technique in revision hip surgery is useful in patients with a well fixed metal backed acetabular component.

  2. Helical plasma striations in liners in the presence of an external axial magnetic field

    NASA Astrophysics Data System (ADS)

    Atoyan, L.; Hammer, D. A.; Kusse, B. R.; Byvank, T.; Cahill, A. D.; Greenly, J. B.; Pikuz, S. A.; Shelkovenko, T. A.

    2016-02-01

    Awe et al. found on the 20 MA Z machine [Acta Phys. Pol. A 115, 956 (2009)] that applying an externally generated axial magnetic field to an imploding liner leads to a helical pattern in the liner when viewed with soft x-ray radiography ([Phys. Rev. Lett. 111, 235005 (2013)] and [Phys. Plasmas 21, 056303 (2014)]). Here, we show that this phenomenon is also observed in extreme ultraviolet self-emission images of 10 mm long cylindrical metal liners having varying diameters and varying wall thicknesses on a 1 MA, 100-200 ns pulsed power generator. The magnetic field in these experiments is created using either twisted return current wires positioned close to the liner, generating a time-varying Bz, or a Helmholtz coil, generating a steady-state Bz.

  3. Sorption Kinetics Of Selected Heavy Metals Adsorption To Natural And Fe(III) Modified Zeolite Tuff Containing Clinoptilolite Mineral

    NASA Astrophysics Data System (ADS)

    Sirotiak, Maroš; Lipovský, Marek; Bartošová, Alica

    2015-06-01

    In the research described in this paper, studied was sorption capacity of natural and ferric modification of zeolite tuff containing mineral clinoptilolite from the Nižný Hrabovec deposit to remove potentially toxic metals (ionic forms of chromium, nickel, copper and aluminium) from their water solutions. We reported that the Fe (III) zeolite has an enhanced ability to sorption of Cu (II), and a slight improvement occurs in the case of Cr (VI) and Ni (II). On the other hand, the deterioration was observed in the case of Al (III) adsorption.

  4. Changes in near-surface microstructure of metallic limiters following one year of service in Doublet III

    SciTech Connect

    Trester, P.W.; Sevier, D.L.; Sabado, M.M.

    1981-08-01

    The structural alloys Ta-10W, Mo, and Inconel X-750 were used for plasma limiters during the 3-MW ohmic heating experiments of the Doublet III tokamak. Post-service examinations of these limiters are reviewed. Near-surface melting, cracking, and microstructural changes are shown and discussed. During III service, elements from other metallic components were transported by the plasma and deposited on the limiter surface; significantly, high concentrations of Ni, Fe, Mo, and C were detected in the regions found to be microcracked in the Ta-10W. Observations and analyses are made that are relevant to the design of limiter and armor components for larger tokamaks.

  5. Fracture of a titanium sleeve-encased third-generation ceramic liner in a modern THA.

    PubMed

    Chotai, Pranit N; Su, Edwin P

    2011-10-01

    Due to their excellent tribology, ceramics are increasingly used for total hip arthroplasty (THA) in young patients. Fracture rates for contemporary ceramics range from 0% to 0.004%. Recently, ceramic liners are encased in a titanium sleeve to further decrease the chances of fracture. We encountered 1 case of a metal-encased acetabular liner fracture in a ceramic-on-ceramic articulation in a series of 764 hips. Our literature review revealed no reports of metal-encased ceramic liner fracture. A 60-year-old woman presented 27 months after a bilateral ceramic-on-ceramic THA. She reported mechanical grinding and clicking from the left hip on extension. There was no history of trauma or fall. Examination revealed a nonantalgic gait and audible-palpable crepitations on the left hip. Range of motion of the left hip was intact with no subluxation. Radiographs revealed fractured ceramic insert and an excessively anteverted socket on the left side. Intraoperative findings revealed gross impingement in the form of indentation of the metal femoral neck against the elevated metal rim encasing the liner. Revision THA was performed using an uncemented polyethylene liner while retaining the well-fixed cup and stem. The Harris Hip Score at 4.5-year follow-up was 100, with no evidence of osteolysis or polyethylene wear.

  6. Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents.

    PubMed

    Yager-Elorriaga, D A; Steiner, A M; Patel, S G; Jordan, N M; Lau, Y Y; Gilgenbach, R M

    2015-11-01

    In this work, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ∼600 kA with ∼200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. This technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines. PMID:26628134

  7. Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents

    SciTech Connect

    Yager-Elorriaga, D. A.; Steiner, A. M.; Patel, S. G.; Jordan, N. M.; Lau, Y. Y.; Gilgenbach, R. M.

    2015-11-19

    In this study, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ~600 kA with ~200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. As a result, this technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines.

  8. Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents

    DOE PAGES

    Yager-Elorriaga, D. A.; Steiner, A. M.; Patel, S. G.; Jordan, N. M.; Lau, Y. Y.; Gilgenbach, R. M.

    2015-11-19

    In this study, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ~600 kA with ~200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. As amore » result, this technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines.« less

  9. Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents

    NASA Astrophysics Data System (ADS)

    Yager-Elorriaga, D. A.; Steiner, A. M.; Patel, S. G.; Jordan, N. M.; Lau, Y. Y.; Gilgenbach, R. M.

    2015-11-01

    In this work, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ˜600 kA with ˜200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. This technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines.

  10. Liner Compression of a MAGO / Inverse-Pinch Configuration

    SciTech Connect

    Siemon, R E; Atchison, W L; Awe, T; Bauer, B S; Buyko, A M; Chernyshev, V K; Cowan, T E; Degnan, J H; Faehl, R J; Fuelling, S; Garanin, S F; Goodrich, T; Ivanovsky, A V; Lindemuth, I R; Makhin, V; Mokhov, V N; Reinovsky, R E; Ryutov, D D; Scudder, D W; Taylor, T; Yakubov, V B

    2005-05-18

    In the ''metal liner'' approach to Magnetized Target Fusion (MTF), a preheated magnetized plasma target is compressed to thermonuclear temperature and high density by externally driving the implosion of a flux conserving metal enclosure, or liner, which contains the plasma target. As in inertial confinement fusion, the principle fusion fuel heating mechanism is pdV work by the imploding enclosure, called a pusher in ICF. One possible MTF target, the hard-core diffuse z pinch, has been studied in MAGO experiments at VNIIEF, and is one possible target being considered for experiments on the Atlas pulsed power facility. Numerical MHD simulations show two intriguing and helpful features of the diffuse z pinch with respect to compressional heating. First, in two-dimensional simulations the m=0 interchange modes, arising from an unstable pressure profile, result in turbulent motions and self-organization into a stable pressure profile. The turbulence also gives rise to convective thermal transport, but the level of turbulence saturates at a finite level, and simulations show substantial heating during liner compression despite the turbulence. The second helpful feature is that pressure profile evolution during compression tends towards improved stability rather than instability when analyzed according to the Kadomtsev criteria. A liner experiment is planned for Atlas to study compression of magnetic flux without plasma as a first step. The Atlas geometry is compatible with a diffuse z pinch, and simulations of possible future experiments show that keV temperatures and useful neutron production for diagnostic purposes should be possible if a suitable plasma injector is added to the Atlas facility.

  11. Stellar populations in Active Galactic Nuclei III

    NASA Astrophysics Data System (ADS)

    Boisson, C.; Joly, M.; Pelat, D.; Ward, M. J.

    2004-12-01

    In this paper we apply the stellar population synthesis method previously described in Boisson et al. (\\cite{Boisson2000}) to five more AGN. The analysis of these new data strengthen our previous conclusions: i) homogeneity of the stellar population within a class of nuclear activity regardless of the morphological type of the host galaxy; ii) populations within the nuclear regions of LINERs and Seyfert 2s are different: LINERs have a very old metal-rich population while in the Seyfert 2s a contribution of a weak burst of star formation is observed together with the old high metallicity component; iii) in the circum-nuclar region (200 pc ≤D≤1 kpc) of all the active galaxies in our sample, except for NGC 2992, we detect an old burst of star formation (0.2-1 Gyr),which is contrary to what is observed in normal galaxies. We note that the broad OIλ8446 Å emission line detected in the spectrum of the nucleus of NGC 2992 confirms its classification as a Seyfert 1. Based on observations collected at the New Technology Telescope of the European Southern Observatory, La Silla, Chile.

  12. Assessing bioavailability levels of metals in effluent-affected rivers: effect of Fe(III) and chelating agents on the distribution of metal speciation.

    PubMed

    Han, Shuping; Naito, Wataru; Masunaga, Shigeki

    2016-01-01

    To assess the effects of Fe(III) and anthropogenic ligands on the bioavailability of Ni, Cu, Zn, and Pb, concentrations of bioavailable metals were measured by the DGT (diffusive gradients in thin films) method in some urban rivers, and were compared with concentrations calculated by a chemical equilibrium model (WHAM 7.0). Assuming that dissolved Fe(III) (<0.45 μm membrane filtered) was in equilibrium with colloidal iron oxide, the WHAM 7.0 model estimated that bioavailable concentrations of Ni, Cu, and Zn were slightly higher than the corresponding values estimated assuming that dissolved Fe(III) was absent. In contrast, lower levels of free Pb were predicted by the WHAM 7.0 model when dissolved Fe(III) was included. Estimates showed that most of the dissolved Pb was present as colloidal iron-Pb complex. Ethylene-diamine-tetra-acetic acid (EDTA) concentrations at sampling sites were predicted from the relationship between EDTA and the calculated bioavailable concentration of Zn. When both colloidal iron and predicted EDTA concentrations were included in the WHAM 7.0 calculations, dissolved metals showed a strong tendency to form EDTA complexes, in the order Ni > Cu > Zn > Pb. With the inclusion of EDTA, bioavailable concentrations of Ni, Cu, and Zn predicted by WHAM 7.0 were different from those predicted considering only humic substances and colloidal iron. PMID:27533864

  13. Metal Reduction and Iron Biomineralization by a Psychrotolerant Fe(III)-Reducing Bacterium, Shewanella sp. Strain PV-4

    SciTech Connect

    Roh, Yul; Gao, Haichun; Vali, Hojatollah; Kennedy, David W.; Yang, Zamin; Gao, Weimin; Dohnalkova, Alice; Stapleton, Raymond D.; Moon, Ji-Won; Phelps, T. J.; Fredrickson, Jim K.; Zhou, Jizhong

    2006-05-01

    A marine psychrotolerant, dissimilatory Fe(III)-reducing bacterium, Shewanella sp. strain PV-4, from the microbial mat at a hydrothermal vent of Loihi Seamount in the Pacific Ocean has been further characterized, with emphases on metal reduction and iron biomineralization. The strain is able to reduce metals such as Fe(III), Co(III), Cr(VI), Mn(IV), and U(VI) as electron acceptors while using lactate, formate, pyruvate, or hydrogen as an electron donor. Growth during iron reduction occurred over the pH range of 7.0 to 8.9, a sodium chloride range of 0.05 to 5%, and a temperature range of 0 to 37°C, with an optimum growth temperature of 18°C. Unlike mesophilic dissimilatory Fe(III)-reducing bacteria, which produce mostly superparamagnetic magnetite (<35 nm), this psychrotolerant bacterium produces well-formed single-domain magnetite (>35 nm) at temperatures from 18 to 37°C. The genome size of this strain is about 4.5 Mb. Strain PV-4 is sensitive to a variety of commonly used antibiotics except ampicillin and can acquire exogenous DNA (plasmid pCM157) through conjugation.

  14. Fabrication of a Kevlar liner assembly

    SciTech Connect

    Schloman, A.H.

    1980-07-01

    Several liner assemblies were fabricated with Kevlar 49 and epoxy using various wet layup and prepreg processes. A production process, using prepreg material, was developed for fabricating the liner and a wet layup molding process was used to fabricate the Kevlar hat-shaped tunnels. Fabrication of the tunnels using Kevlar prepreg with an autoclave curving process was evaluated.

  15. Shock wave absorber having a deformable liner

    DOEpatents

    Youngdahl, C.K.; Wiedermann, A.H.; Shin, Y.W.; Kot, C.A.; Ockert, C.E.

    1983-08-26

    This invention discloses a shock wave absorber for a piping system carrying liquid. The absorber has a plastically deformable liner defining the normal flow boundary for an axial segment of the piping system, and a nondeformable housing is spaced outwardly from the liner so as to define a gas-tight space therebetween. The flow capacity of the liner generally corresponds to the flow capacity of the piping system line, but the liner has a noncircular cross section and extends axially of the piping system line a distance between one and twenty times the diameter thereof. Gas pressurizes the gas-tight space equal to the normal liquid pressure in the piping system. The liner has sufficient structural capacity to withstand between one and one-half and two times this normal liquid pressures; but at greater pressures it begins to plastically deform initially with respect to shape to a more circular cross section, and then with respect to material extension by circumferentially stretching the wall of the liner. A high energy shock wave passing through the liner thus plastically deforms the liner radially into the gas space and progressively also as needed in the axial direction of the shock wave to minimize transmission of the shock wave beyond the absorber.

  16. HYDRAULIC CONDUCTIVITY OF THREE GEOSYNTHETIC CLAY LINERS

    EPA Science Inventory

    The hydraulic conductivity of three 2.9 m2 (32 sq ft) geosynthetic clay liners (GCLs) was measured. Tests were performed on individual sheets of the GCLs, on overlapped pieces of GCLs, and on composite liners consisting of a punctured geomembrane overlying a GCL. Hyd...

  17. Fe(III) hydroxide nucleation and growth on quartz in the presence of Cu(II), Pb(II), and Cr(III): metal hydrolysis and adsorption.

    PubMed

    Dai, Chong; Hu, Yandi

    2015-01-01

    Fe(III) hydroxide nanoparticles are an essential carrier for aqueous heavy metals. Particularly, iron hydroxide precipitation on mineral surfaces can immobilize aqueous heavy metals. Here, we used grazing-incidence small-angle X-ray scattering (GISAXS) to quantify nucleation and growth of iron hydroxide on quartz in 0.1 mM Fe(NO3)3 solution in the presence of Na(+), Cu(2+), Pb(2+), or Cr(3+) at pH = 3.7 ± 0.1. In 30 min, the average radii of gyration (R(g)) of particles on quartz grew from around 2 to 6 nm in the presence of Na(+) and Cu(2+). Interestingly, the particle sizes remained 3.3 ± 0.3 nm in the presence of Pb(2+), and few particles formed in the presence of Cr(3+). Quartz crystal microbalance dissipation (QCM-D) measurements showed that only Cr(3+) adsorbed onto quartz, while Cu(2+) and Pb(2+) did not. Cr(3+) adsorption changed the surface charge of quartz from negative to positive, thus inhibiting the precipitation of positively charged iron hydroxide on quartz. Masses and compositions of the precipitates were also quantified. This study provided new insights on interactions among quartz, iron hydroxide, and metal ions. Such information is helpful not only for environmental remediation but also for the doping design of iron oxide catalysts. PMID:25496643

  18. Fe(III) hydroxide nucleation and growth on quartz in the presence of Cu(II), Pb(II), and Cr(III): metal hydrolysis and adsorption.

    PubMed

    Dai, Chong; Hu, Yandi

    2015-01-01

    Fe(III) hydroxide nanoparticles are an essential carrier for aqueous heavy metals. Particularly, iron hydroxide precipitation on mineral surfaces can immobilize aqueous heavy metals. Here, we used grazing-incidence small-angle X-ray scattering (GISAXS) to quantify nucleation and growth of iron hydroxide on quartz in 0.1 mM Fe(NO3)3 solution in the presence of Na(+), Cu(2+), Pb(2+), or Cr(3+) at pH = 3.7 ± 0.1. In 30 min, the average radii of gyration (R(g)) of particles on quartz grew from around 2 to 6 nm in the presence of Na(+) and Cu(2+). Interestingly, the particle sizes remained 3.3 ± 0.3 nm in the presence of Pb(2+), and few particles formed in the presence of Cr(3+). Quartz crystal microbalance dissipation (QCM-D) measurements showed that only Cr(3+) adsorbed onto quartz, while Cu(2+) and Pb(2+) did not. Cr(3+) adsorption changed the surface charge of quartz from negative to positive, thus inhibiting the precipitation of positively charged iron hydroxide on quartz. Masses and compositions of the precipitates were also quantified. This study provided new insights on interactions among quartz, iron hydroxide, and metal ions. Such information is helpful not only for environmental remediation but also for the doping design of iron oxide catalysts.

  19. Water movement through an experimental soil liner

    USGS Publications Warehouse

    Krapac, I.G.; Cartwright, K.; Panno, S.V.; Hensel, B.R.; Rehfeldt, K.R.; Herzog, B.L.

    1991-01-01

    A field-scale soil liner was constructed to test whether compacted soil barriers in cover and liner systems could be built to meet the U.S. EPA saturated hydraulic conductivity requirement (???1 x 10-7 cm s-1). The 8 x 15 x 0.9m liner was constructed in 15 cm compacted lifts using a 20,037 kg pad-foot compactor and standard engineering practices. Water infiltration into the liner has been monitored for one year. Monitoring will continue until water break through at the base of the liner occurs. Estimated saturated hydraulic conductivities were 2.5 x 10-9, 4.0 x 10-8, and 5.0 x 10-8 cm s-1 based on measurements of water infiltration into the liner by large- and small-ring infiltrometers and a water balance analysis, respectively. Also investigated in this research was the variability of the liner's hydraulic properties and estimates of the transit times for water and tracers. Small variances exhibited by small-ring flux data suggested that the liner was homogeneous with respect to infiltration fluxes. The predictions of water and tracer breakthrough at the base of the liner ranged from 2.4-12.6 y, depending on the method of calculation and assumptions made. The liner appeared to be saturated to a depth between 18 and 33 cm at the end of the first year of monitoring. Transit time calculations cannot be verified yet, since breakthrough has not occurred. The work conducted so far indicates that compacted soil barriers can be constructed to meet the saturated hydraulic conductivity requirement established by the U.S. EPA.A field-scale soil liner was constructed to test whether compacted soil barriers in cover and liner systems could be built to meet the U.S. EPA saturated hydraulic conductivity requirement (??? 1 ?? 10-7 cm s-1). The 8 ?? 15 ?? 0.9 m liner was constructed in 15 cm compacted lifts using a 20.037 kg pad-foot compactor and standard engineering practices. Water infiltration into the liner has been monitored for one year. Monitoring will continue until water

  20. Stabilized Liner Compressor: The Return of Linus

    NASA Astrophysics Data System (ADS)

    Turchi, Peter; Frese, Sherry; Frese, Michael; Mielke, Charles; Hinrichs, Mark; Nguyen, Doan

    2015-11-01

    To access the lower cost regime of magneto-inertial fusion at megagauss magnetic field-levels requires the use of dynamic conductors in the form of imploding cylindrical shells, aka, liners. Such liner implosions can compress magnetic flux and plasma to attain fusion conditions, but are subject to Rayleigh-Taylor instabilities, both in the launch and recovery of the liner material and in the final few diameters of implosion. These instabilities were overcome in the Linus program at the Naval Research Laboratory, c. 1979, providing the experimentally-demonstrated basis for repetitive operation and leading to an economical reactor concept at low fusion gain. The recent ARPA-E program for low-cost fusion technology has revived interest in this approach. We shall discuss progress in modeling and design of a Stabilized Liner Compressor (SLC) that extends the earlier work to higher pressures and liner speeds appropriate to potential plasma targets. Sponsored by ARPA-E ALPHA Program.

  1. Accelerating Thick Aluminum Liners Using Pulsed Power

    SciTech Connect

    Kyrala, G.A.; Hammerburg, J.E.; Bowers, D.; Stokes, J.; Morgan, D.V.; Anderson, W.E.; Cochrane, J.C.

    1999-06-28

    The authors have investigated the acceleration of very thick cylindrical aluminum liners using the Pegasus II capacitory bank. These accelerated solid liners will be used to impact other objects at velocities below 1.5 km/sec, allowing one to generate and sustain shocks of a few 100 kilobar for a few microseconds. A cylindrical shell of 1100 series aluminum with an initial inner radius of 23.61 mm, an initial thickness of 3.0 mm, and a height of 20 mm, was accelerated using a current pulse of 7.15 MA peak current and a 7.4 microsecond quarter cycle time. The aluminum shell was imploded within confining copper glide planes with decreasing separation with an inward slope of 8 degrees. At impact with a cylindrical target of diameter 3-cm, the liner was moving at 1.4 km/sec and its thickness increased to 4.5 mm. Radial X-ray radiograms of the liner showed both the liner and the glide plane interface. The curvature of the inner surface of the liner was measured before impact with the 15-mm radius target. The radiograms also showed that the copper glide planes distorted as the liner radius decreased and that some axial stress is induced in the liner. The axial stresses did not affect the inner curvature significantly. Post-shot calculations of the liner behavior indicated that the thickness of the glide plane played a significant role in the distortion of the interface between the liner and the glide plane.

  2. Three new europium(III) methanetriacetate metal-organic frameworks: the influence of synthesis on the product topology.

    PubMed

    Cañadillas-Delgado, Laura; Fabelo, Oscar; Pasán, Jorge; Déniz, Mariadel; Martínez-Benito, Carla; Díaz-Gallifa, Pau; Martín, Tomás; Ruiz-Pérez, Catalina

    2014-02-01

    Three new metal-organic framework structures containing Eu(III) and the little explored methanetriacetate (C7H7O6(3-), mta(3-)) ligand have been synthesized. Gel synthesis yields a two-dimensional framework with the formula [Eu(mta)(H2O)3]n·2nH2O, (I), while two polymorphs of the three-dimensional framework material [Eu(mta)(H2O)]n·nH2O, (II) and (III), are obtained through hydrothermal synthesis at either 423 or 443 K. Compounds (I) and (II) are isomorphous with previously reported Gd(III) compounds, but compound (III) constitutes a new phase. Compound (I) can be described in terms of dinuclear [Eu2(H2O)4](6+) units bonded through mta(3-) ligands to form a two-dimensional framework with topology corresponding to a (6,3)-connected binodal (4(3))(4(6)6(6)8(3))-kgd net, where the dinuclear [Eu2(H2O)4](6+) units are considered as a single node. Compounds (II) and (III) have distinct three-dimensional topologies, namely a (4(12)6(3))(4(9)6(6))-nia net for (II) and a (4(10)6(5))(4(11)6(4))-K2O2; 36641 net for (III). The crystal density of (III) is greater than that of (II), consistent with the increase of temperature, and thereby autogeneous pressure, in the hydrothermal synthesis. PMID:24441124

  3. Large Engine Technology Program. Task 21: Rich Burn Liner for Near Term Experimental Evaluations

    NASA Technical Reports Server (NTRS)

    Hautman, D. J.; Padget, F. C.; Kwoka, D.; Siskind, K. S.; Lohmann, R. P.

    2005-01-01

    The objective of the task reported herein, which was conducted as part of the NASA sponsored Large Engine Technology program, was to define and evaluate a near-term rich-zone liner construction based on currently available materials and fabrication processes for a Rich-Quench-Lean combustor. This liner must be capable of operation at the temperatures and pressures of simulated HSCT flight conditions but only needs sufficient durability for limited duration testing in combustor rigs and demonstrator engines in the near future. This must be achieved at realistic cooling airflow rates since the approach must not compromise the emissions, performance, and operability of the test combustors, relative to the product engine goals. The effort was initiated with an analytical screening of three different liner construction concepts. These included a full cylinder metallic liner and one with multiple segments of monolithic ceramic, both of which incorporated convective cooling on the external surface using combustor airflow that bypassed the rich zone. The third approach was a metallic platelet construction with internal convective cooling. These three metal liner/jacket combinations were tested in a modified version of an existing Rich-Quench-Lean combustor rig to obtain data for heat transfer model refinement and durability verification.

  4. Utilization of sepiolite materials as a bottom liner material in solid waste landfills.

    PubMed

    Guney, Yucel; Cetin, Bora; Aydilek, Ahmet H; Tanyu, Burak F; Koparal, Savas

    2014-01-01

    Landfill bottom liners are generally constructed with natural clay soils due to their high strength and low hydraulic conductivity characteristics. However, in recent years it is increasingly difficult to find locally available clay soils that satisfy the required engineering properties. Fine grained soils such as sepiolite and zeolite may be used as alternative materials in the constructions of landfill bottom liners. A study was conducted to investigate the feasibility of using natural clay rich in kaolinite, sepiolite, zeolite, and their mixtures as a bottom liner material. Unconfined compression tests, swell tests, hydraulic conductivity tests, batch and column adsorption tests were performed on each type of soil and sepiolite-zeolite mixtures. The results of the current study indicate that sepiolite is the dominant material that affects both the geomechanical and geoenvironmental properties of these alternative liners. An increase in sepiolite content in the sepiolite-zeolite mixtures increased the strength, swelling potential and metal adsorption capacities of the soil mixtures. Moreover, hydraulic conductivity of the mixtures decreased significantly with the addition of sepiolite. The utilization of sepiolite-zeolite materials as a bottom liner material allowed for thinner liners with some reduction in construction costs compared to use of a kaolinite-rich clay. PMID:24220149

  5. Dislocation of a dual mobility total hip replacement following fracture of the polyethylene liner.

    PubMed

    Vedrine, Bertrand; Guillaumot, Pierre; Chancrin, Jean-Luc

    2016-05-18

    An eight-year-old male English Setter was referred for management of a dislocation of a cemented dual mobility canine total hip prosthesis that occurred four months after the initial surgery. Revision surgery showed that the dislocation was associated with fracture of the ultra-high molecular weight polyethylene liner. The dislocation was successfully reduced after replacing the liner. A dual mobility acetabular component is composed of a mobile polyethylene liner inside a metallic cemented cup. Chronic wear of the components of a canine dual mobility total hip replacement has not been described previously. The use of this type of implant is fairly recent and limited long term follow-up of the implanted cases may be the explanation. Acute rupture of a polyethylene liner has never been described in humans, the only case of rupture of a polyethylene liner occurred 10 years after implantation. The case presented here of rupture of the polyethylene liner of a dual mobility total hip replacement is a hitherto unreported failure mode in this model of acetabular cup in the dog. PMID:26991949

  6. Immobilized metal affinity chromatography on collapsed Langmuir-Blodgett iron(III) stearate films and iron(III) oxide nanoparticles for bottom-up phosphoproteomics.

    PubMed

    Gladilovich, Vladimir; Greifenhagen, Uta; Sukhodolov, Nikolai; Selyutin, Artem; Singer, David; Thieme, Domenika; Majovsky, Petra; Shirkin, Alexey; Hoehenwarter, Wolfgang; Bonitenko, Evgeny; Podolskaya, Ekaterina; Frolov, Andrej

    2016-04-22

    Phosphorylation is the enzymatic reaction of site-specific phosphate transfer from energy-rich donors to the side chains of serine, threonine, tyrosine, and histidine residues in proteins. In living cells, reversible phosphorylation underlies a universal mechanism of intracellular signal transduction. In this context, analysis of the phosphoproteome is a prerequisite to better understand the cellular regulatory networks. Conventionally, due to the low contents of signaling proteins, selective enrichment of proteolytic phosphopeptides by immobilized metal affinity chromatography (IMAC) is performed prior to their LC-MS or -MS/MS analysis. Unfortunately, this technique still suffers from low selectivity and compromised analyte recoveries. To overcome these limitations, we propose IMAC systems comprising stationary phases based on collapsed Langmuir-Blodgett films of iron(III) stearate (FF) or iron(III) oxide nanoparticles (FO) and mobile phases relying on ammonia, piperidine and heptadecafluorooctanesulfonic acid (PFOS). Experiments with model phosphopeptides and phosphoprotein tryptic digests showed superior binding capacity, selectivity and recovery for both systems in comparison to the existing commercial analogs. As evidenced by LC-MS/MS analysis of the HeLa phosphoproteome, these features of the phases resulted in increased phosphoproteome coverage in comparison to the analogous commercially available phases, indicating that our IMAC protocol is a promising chromatographic tool for in-depth phosphoproteomic research.

  7. Immobilized metal affinity chromatography on collapsed Langmuir-Blodgett iron(III) stearate films and iron(III) oxide nanoparticles for bottom-up phosphoproteomics.

    PubMed

    Gladilovich, Vladimir; Greifenhagen, Uta; Sukhodolov, Nikolai; Selyutin, Artem; Singer, David; Thieme, Domenika; Majovsky, Petra; Shirkin, Alexey; Hoehenwarter, Wolfgang; Bonitenko, Evgeny; Podolskaya, Ekaterina; Frolov, Andrej

    2016-04-22

    Phosphorylation is the enzymatic reaction of site-specific phosphate transfer from energy-rich donors to the side chains of serine, threonine, tyrosine, and histidine residues in proteins. In living cells, reversible phosphorylation underlies a universal mechanism of intracellular signal transduction. In this context, analysis of the phosphoproteome is a prerequisite to better understand the cellular regulatory networks. Conventionally, due to the low contents of signaling proteins, selective enrichment of proteolytic phosphopeptides by immobilized metal affinity chromatography (IMAC) is performed prior to their LC-MS or -MS/MS analysis. Unfortunately, this technique still suffers from low selectivity and compromised analyte recoveries. To overcome these limitations, we propose IMAC systems comprising stationary phases based on collapsed Langmuir-Blodgett films of iron(III) stearate (FF) or iron(III) oxide nanoparticles (FO) and mobile phases relying on ammonia, piperidine and heptadecafluorooctanesulfonic acid (PFOS). Experiments with model phosphopeptides and phosphoprotein tryptic digests showed superior binding capacity, selectivity and recovery for both systems in comparison to the existing commercial analogs. As evidenced by LC-MS/MS analysis of the HeLa phosphoproteome, these features of the phases resulted in increased phosphoproteome coverage in comparison to the analogous commercially available phases, indicating that our IMAC protocol is a promising chromatographic tool for in-depth phosphoproteomic research. PMID:27016113

  8. A synthetic route to ultralight hierarchically micro/mesoporous Al(III)-carboxylate metal-organic aerogels

    PubMed Central

    Li, Lei; Xiang, Shenglin; Cao, Shuqi; Zhang, Jianyong; Ouyang, Gangfeng; Chen, Liuping; Su, Cheng-Yong

    2013-01-01

    Developing a synthetic methodology for the fabrication of hierarchically porous metal-organic monoliths that feature high surface area, low density and tunable porosity is imperative for mass transfer applications, including bulky molecule capture, heterogeneous catalysis and drug delivery. Here we report a versatile and facile synthetic route towards ultralight micro/mesoporous metal-organic aerogels based on the two-step gelation of metal-organic framework nanoparticles. Heating represents a key factor in the control of gelation versus crystallization of Al(III)-multicarboxylate systems. The porosity of the resulting metal-organic aerogels can be readily tuned, leading to the formation of well-ordered intraparticle micropores and aerogel-specific interparticle mesopores, thereby integrating the merits of both crystalline metal-organic frameworks and light aerogels. The hierarchical micro/mesoporosity of the Al-metal-organic aerogels is thoroughly evaluated by N2 sorption. The good accessibility of the micro/mesopores is verified by vapour/dye uptake, and their potential for utilization as effective fibre-coating absorbents is tested in solid-phase microextraction analyses. PMID:23653186

  9. Excited-state properties of a triply ortho-metalated iridium(III) complex

    SciTech Connect

    King, K.A.; Spellane, P.J.; Watts, R.J.

    1985-03-06

    The characterization of the ground and luminescent excited states of a triply ortho-metalated complex of ppy, fac-Ir(ppy)/sub 3/ (ppy = 2-phenylpyridine) is effected. This complex, which is the first triply ortho-metalated ppy species to be characterized, is one of the strongest transition-metal photoreductants thus far reported. 20 references, 2 figures.

  10. Ultraviolet spectrophotometry of three LINERs

    NASA Technical Reports Server (NTRS)

    Goodrich, R. W.; Keel, W. C.

    1986-01-01

    Three galaxies known to be LINERs were observed spectroscopically in the ultraviolet in an attempt to detect the presumed nonthermal continuum source thought to be the source of photoionization in the nuclei. NGC 4501 was found to be too faint for study with the IUE spectrographs, while NGC 5005 had an extended ultraviolet light profile. Comparison with the optical light profile of NGC 5005 indicates that the ultraviolet source is distributed spatially in the same manner as the optical starlight, probably indicating that the ultraviolet excess is due to a component of hot stars in the nucleus. These stars contribute detectable absorption features longward of 2500 A; together with optical data, the IUE spectra suggest a burst of star formation about 1 billion yr ago, with a lower rate continuing to produce a few OB stars. In NGC 4579, a point source contributing most of the ultraviolet excess is found that is much different than the optical light distribution. Furthermore, the ultraviolet to X-ray spectral index in NGC 4579 is 1.4, compatible with the UV to X-ray indices found for samples of Seyfert galaxies. This provides compelling evidence for the detection of the photoionizing continuum in NGC 4579 and draws the research fields of normal galaxies and active galactic nuclei closer together. The emission-line spectrum of NGC 4579 is compared with calculations from a photoionization code, CLOUDY, and several shock models. The photoionization code is found to give superior results, adding to the increasing weight of evidence that the LINER phenomenon is essentially a scaled-down version of the Seyfert phenomenon.

  11. Development of plasma spray coated cylinder liners

    SciTech Connect

    Tricard, M.; Hagan, J.; Redington, P.; Subramanian, K.; Haselkorn, M.

    1996-09-01

    Improved fuel economy and reduction of emissions can be achieved by insulation of the combustion chamber components to reduce heat rejection. However, such insulation will also increase the operating temperature of the piston ring/cylinder liner interface from approximately 150 C to over 300 C. Since existing ring/liner materials cannot withstand these higher operating temperatures alternatives are needed for this critical tribological interface. This paper describes the development of a cost effective ID grinding technique for machining the bores of plasma sprayed diesel engine cylinder liners.

  12. Refractory liner materials used in slagging gasifiers

    SciTech Connect

    Bennett, James P.

    2004-09-01

    Refractory liners are used on the working face of entrained flow slagging gasifiers that react coal, petroleum coke, or other carbon feedstock with oxygen and water. The refractory liners protect the gasifier shell from elevated temperatures, corrosive slags, and thermal cycling during gasification. Refractory failure is primarily by two means, corrosive dissolution and spalling. High chrome oxide refractory materials have evolved as the material of choice to line the hot face of gasifiers, yet the performance of these materials does not meet the service requirements of industry. A review of gasifier liner materials, their evolution, issues impacting their performance, and future research direction are discussed.

  13. Synthesis, structural characterization, luminescent properties and theoretical study of three novel lanthanide metal-organic frameworks of Ho(III), Gd(III) and Eu(III) with 2,5-thiophenedicarboxylate anion

    SciTech Connect

    Marques, Lippy F.; Correa, Charlane C.; Ribeiro, Sidney J.L.; Santos, Molíria V. dos; Dutra, José Diogo L.; Freire, Ricardo O.; Machado, Flávia C.

    2015-07-15

    In this paper, the synthesis of three new metal-organic frameworks of lanthanides (LnMOFs) ([Ln{sub 2}(2,5-tdc){sub 3}(dmso){sub 2}]·H{sub 2}O){sub n} (Ln=Ho (1); Gd (2); Eu (3); 2,5-tdc=2,5-thiophenedicarboxylate anion; dmso=dimethylsulfoxide), and their complete characterization, including single crystal X-ray diffraction, FTIR spectroscopy and thermogravimetric analysis are reported. In especial, photophysical properties of Eu(III) complex have been studied in detail via both theoretical and experimental approaches. Crystal structure of (1) reveals that each lanthanide ion is seven-coordinated by oxygen atoms in an overall distorted capped trigonal – prismatic geometry. The 2,5-tdc{sup 2−} ligands connect four Ln(III) centers, adopting (κ{sup 1}–κ{sup 1})–(κ{sup 1}–κ{sup 1})–μ{sub 4} coordination mode, generating an 8-connected uninodal 3D network. In addition, theoretical studies for Eu(III) complex were performed using the Sparkle model for lanthanide complexes. - Graphical abstract: Three new metal-organic frameworks of lanthanides (LnMOFs) ([Ln{sub 2}(2,5-tdc){sub 3}(dmso){sub 2}]·H{sub 2}O){sub n} (Ln=Ho (1); Gd (2); Eu (3); 2,5-tdc=2,5-thiophenedicarboxylate anion; dmso=dimethylsulfoxide), were synthesized and their complete characterization, including single crystal X-ray diffraction, FTIR spectroscopy and thermogravimetric analysis are reported. In especial, photophysical properties of Eu(III) complex have been studied in detail via both theoretical and experimental approaches. - Highlights: • Three new LnMOFs were synthesized and fully characterized. • Ho{sup 3+}, Gd{sup 3+} and Eu{sup 3+} complexes photoluminescence properties were investigated. • Theoretical approaches for Eu{sup 3+} complex luminescence has been performed. • An energy level diagram is used to establish the ligand-to-metal energy transfer. • These metal−organic frameworks can act as light conversion molecular devices.

  14. Early time studies of cylindrical liner implosions at 1 MA on COBRA

    SciTech Connect

    Atoyan, L. Byvank, T. Cahill, A. D. Hoyt, C. L. Grouchy, P. W. L. de Potter, W. M. Kusse, B. R. Hammer, D. A.

    2014-12-15

    Tests of the magnetized liner inertial fusion (MagLIF) concept will make use of the 27 MA Z machine at Sandia National Laboratories, Albuquerque, to implode a cylindrical metal liner to compress and heat preheated, magnetized plasma contained within it. While most pulsed power machines produce much lower currents than the Z-machine, there are issues that can still be addressed on smaller scale facilities. Recent work on the Cornell Beam Research Accelerator (COBRA) has made use of 10 mm long and 4 mm diameter metal liners having different wall thicknesses to study the initiation of plasma on the liner’s surface as well as axial magnetic field compression [P.-A. Gourdain et al., Nucl. Fusion 53, 083006 (2013)]. This report presents experimental results with non-imploding liners, investigating the impact the liner’s surface structure has on initiation and ablation. Extreme ultraviolet (XUV) imaging and optical 12 frame camera imaging were used to observe and assess emission non-uniformities as they developed. Axial and side-on interferometry was used to determine the distribution of plasma near the liner surface, including the impact of non-uniformities during the plasma initiation and ablation phases of the experiments.

  15. Wear versus Thickness and Other Features of 5-Mrad Crosslinked UHMWPE Acetabular Liners

    PubMed Central

    Shen, Fu-Wen; Lu, Zhen

    2010-01-01

    Background The low wear rates of crosslinked polyethylenes provide the potential to use larger diameters to resist dislocation. However, this requires the use of thinner liners in the acetabular component, with concern that higher contact stresses will increase wear, offsetting the benefits of the crosslinking. Questions/purposes We asked the following questions: Is the wear of conventional and crosslinked polyethylene liners affected by ball diameter, rigidity of backing, and liner thickness? Are the stresses in the liner affected by thickness? Methods Wear rates were measured in a hip simulator and stresses were calculated using finite element modeling. Results Without crosslinking, the wear rate was 4% to 10% greater with a 36-mm diameter than a 28-mm diameter. With crosslinking, wear was 9% lower with a 36-mm diameter without metal backing and 4% greater with metal backing. Reducing the thickness from 6 mm to 3 mm increased the contact stress by 46%, but the wear rate decreased by 19%. Conclusions The reduction in wear with 5 Mrad of crosslinking was not offset by increasing the diameter from 28 mm to 36 mm or by using a liner as thin as 3 mm. Clinical Relevance The results indicate, for a properly positioned 5-Mrad crosslinked acetabular component and within the range of dimensions evaluated, neither wear nor stresses in the polyethylene are limiting factors in the use of larger-diameter, thinner cups to resist dislocation. PMID:20848244

  16. Theory of formation of helical structures in a perfectly conducting, premagnetized Z-pinch liner

    NASA Astrophysics Data System (ADS)

    Yu, Edmund; Velikovich, Alexander; Peterson, Kyle

    2014-10-01

    The magnetized liner inertial fusion (MagLIF) concept uses an azimuthal magnetic field to collapse a thick metallic liner containing preheated fusion fuel. A critical component of the concept is an axial magnetic field, permeating both the fuel and surrounding liner, which reduces the compression necessary to achieve fusion conditions. Recent experiments demonstrate that a liner premagnetized with a 10 T axial field develops helical structures with a pitch significantly larger than an estimate of Bz /Bθ would suggest. The cause of the helical perturbations is still not understood. In this work, we present an analytic, linear theory in which we model the liner as a perfectly conducting metal, and study how bumps and divots on its surface redirect current flow, resulting in perturbations to B as well as j × B . We show that in the presence of axial and azimuthal magnetic field, the theory predicts divots will grow and deform at an angle determined by the magnetic field. We compare theoretical results with three dimensional, resistive MHD simulations. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under DE-AC04-94AL85000.

  17. Beryllium liner implosion experiments on the Z accelerator in preparation for magnetized liner inertial fusion

    SciTech Connect

    McBride, R. D.; Martin, M. R.; Lemke, R. W.; Jennings, C. A.; Rovang, D. C.; Sinars, D. B.; Cuneo, M. E.; Herrmann, M. C.; Slutz, S. A.; Nakhleh, C. W.; Davis, J.-P.; Flicker, D. G.; Rogers, T. J.; Robertson, G. K.; Kamm, R. J.; Smith, I. C.; Savage, M.; Stygar, W. A.; Rochau, G. A.; Jones, M.; and others

    2013-05-15

    Multiple experimental campaigns have been executed to study the implosions of initially solid beryllium (Be) liners (tubes) on the Z pulsed-power accelerator. The implosions were driven by current pulses that rose from 0 to 20 MA in either 100 or 200 ns (200 ns for pulse shaping experiments). These studies were conducted in support of the recently proposed Magnetized Liner Inertial Fusion concept [Slutz et al., Phys. Plasmas 17, 056303 (2010)], as well as for exploring novel equation-of-state measurement techniques. The experiments used thick-walled liners that had an aspect ratio (initial outer radius divided by initial wall thickness) of either 3.2, 4, or 6. From these studies, we present three new primary results. First, we present radiographic images of imploding Be liners, where each liner contained a thin aluminum sleeve for enhancing the contrast and visibility of the liner's inner surface in the images. These images allow us to assess the stability of the liner's inner surface more accurately and more directly than was previously possible. Second, we present radiographic images taken early in the implosion (prior to any motion of the liner's inner surface) of a shockwave propagating radially inward through the liner wall. Radial mass density profiles from these shock compression experiments are contrasted with profiles from experiments where the Z accelerator's pulse shaping capabilities were used to achieve shockless (“quasi-isentropic”) liner compression. Third, we present “micro-B-dot ” measurements of azimuthal magnetic field penetration into the initially vacuum-filled interior of a shocked liner. Our measurements and simulations reveal that the penetration commences shortly after the shockwave breaks out from the liner's inner surface. The field then accelerates this low-density “precursor” plasma to the axis of symmetry.

  18. DFT modeling and spectroscopic study of metal ligand bonding in La(III) complex of coumarin-3-carboxylic acid

    NASA Astrophysics Data System (ADS)

    Mihaylov, Tz.; Trendafilova, N.; Kostova, I.; Georgieva, I.; Bauer, G.

    2006-09-01

    The binding mode of coumarin-3-carboxylic acid (HCCA) to La(III) is elucidated at experimental and theoretical level. The complexation ability of the deprotonated ligand (CCA -) to La(III) is studied using elemental analysis, DTA and TGA data as well as FTIR, 1H NMR and 13C NMR spectra. The experimental data suggest the complex formula La(CCA) 2(NO 3)(H 2O) 2. B3LYP, BHLYP, B3P86, B3PW91, PW91P86 and MPW1PW91 functionals are tested for geometry and frequency calculations of the neutral ligand and all of them show bond length deviations bellow 1%. B3LYP/6-31G(d) level combined with large quasi-relativistic effective core potential for lanthanum is selected to describe the molecular, electronic and vibrational structures as well as the conformational behavior of HCCA, CCA - and La-CCA complex. The metal-ligand binding mode is predicted through molecular modeling and energy estimation of different La-CCA structures. The calculated atomic charges and the bonding orbital polarizations point to strong ionic metal-ligand bonding in La-CCA complex and insignificant donor acceptor interaction. Detailed vibrational analysis of HCCA, CCA - and La(CCA) 2(NO 3)(H 2O) 2 systems based on both calculated and experimental frequencies confirms the suggested metal-ligand binding mode.

  19. Accumulation capacitance frequency dispersion of III-V metal-insulator-semiconductor devices due to disorder induced gap states

    SciTech Connect

    Galatage, R. V.; Zhernokletov, D. M.; Dong, H.; Brennan, B.; Hinkle, C. L.; Wallace, R. M.; Vogel, E. M.

    2014-07-07

    The origin of the anomalous frequency dispersion in accumulation capacitance of metal-insulator-semiconductor devices on InGaAs and InP substrates is investigated using modeling, electrical characterization, and chemical characterization. A comparison of the border trap model and the disorder induced gap state model for frequency dispersion is performed. The fitting of both models to experimental data indicate that the defects responsible for the measured dispersion are within approximately 0.8 nm of the surface of the crystalline semiconductor. The correlation between the spectroscopically detected bonding states at the dielectric/III-V interface, the interfacial defect density determined using capacitance-voltage, and modeled capacitance-voltage response strongly suggests that these defects are associated with the disruption of the III-V atomic bonding and not border traps associated with bonding defects within the high-k dielectric.

  20. Accumulation capacitance frequency dispersion of III-V metal-insulator-semiconductor devices due to disorder induced gap states

    NASA Astrophysics Data System (ADS)

    Galatage, R. V.; Zhernokletov, D. M.; Dong, H.; Brennan, B.; Hinkle, C. L.; Wallace, R. M.; Vogel, E. M.

    2014-07-01

    The origin of the anomalous frequency dispersion in accumulation capacitance of metal-insulator-semiconductor devices on InGaAs and InP substrates is investigated using modeling, electrical characterization, and chemical characterization. A comparison of the border trap model and the disorder induced gap state model for frequency dispersion is performed. The fitting of both models to experimental data indicate that the defects responsible for the measured dispersion are within approximately 0.8 nm of the surface of the crystalline semiconductor. The correlation between the spectroscopically detected bonding states at the dielectric/III-V interface, the interfacial defect density determined using capacitance-voltage, and modeled capacitance-voltage response strongly suggests that these defects are associated with the disruption of the III-V atomic bonding and not border traps associated with bonding defects within the high-k dielectric.

  1. Impact of two iron(III) chelators on the iron, cadmium, lead and nickel accumulation in poplar grown under heavy metal stress in hydroponics.

    PubMed

    Mihucz, Victor G; Csog, Árpád; Fodor, Ferenc; Tatár, Enikő; Szoboszlai, Norbert; Silaghi-Dumitrescu, Luminiţa; Záray, Gyula

    2012-04-15

    Poplar (Populus jacquemontiana var. glauca cv. Kopeczkii) was grown in hydroponics containing 10 μM Cd(II), Ni(II) or Pb(II), and Fe as Fe(III) EDTA or Fe(III) citrate in identical concentrations. The present study was designed to compare the accumulation and distribution of Fe, Cd, Ni and Pb within the different plant compartments. Generally, Fe and heavy-metal accumulation were higher by factor 2-7 and 1.6-3.3, respectively, when Fe(III) citrate was used. Iron transport towards the shoot depended on the Fe(III) chelate and, generally, on the heavy metal used. Lead was accumulated only in the root. The amounts of Fe and heavy metals accumulated by poplar were very similar to those of cucumber grown in an identical way, indicating strong Fe uptake regulation of these two Strategy I plants: a cultivar and a woody plant. The Strategy I Fe uptake mechanism (i.e. reducing Fe(III) followed by Fe(II) uptake), together with the Fe(III) chelate form in the nutrient solution had significant effects on Fe and heavy metal uptake. Poplar appears to show phytoremediation potential for Cd and Ni, as their transport towards the shoot was characterized by 51-54% and 26-48% depending on the Fe(III) supply in the nutrient solution.

  2. Crystal structure of hydrazine iron(III) phosphate, the first transition metal phosphate containing hydrazine

    PubMed Central

    David, Renald

    2015-01-01

    The title compound, poly[(μ2-hydrazine)(μ4-phosphato)iron(III)], [Fe(PO4)(N2H4)]n, was prepared under hydro­thermal conditions. Its asymmetric unit contains one FeIII atom located on an inversion centre, one P atom located on a twofold rotation axis, and two O, one N and two H atoms located on general positions. The FeIII atom is bound to four O atoms of symmetry-related PO4 tetra­hedra and to two N atoms of two symmetry-related hydrazine ligands, resulting in a slightly distorted FeO4N2 octa­hedron. The crystal structure consists of a three-dimensional hydrazine/iron phoshate framework whereby each PO4 tetra­hedron bridges four FeIII atoms and each hydrazine ligand bridges two FeIII atoms. The H atoms of the hydrazine ligands are also involved in moderate N—H⋯O hydrogen bonding with phosphate O atoms. The crystal structure is isotypic with the sulfates [Co(SO4)(N2H4)] and [Mn(SO4)(N2H4)]. PMID:26870399

  3. Diiron(III)-μ-Fluoro Bisporphyrins: Effect of Bridging Ligand on the Metal Spin State.

    PubMed

    Sil, Debangsu; Kumar, Amit; Rath, Sankar Prasad

    2016-08-01

    A hitherto unknown family of diiron(III)-μ-fluoro bisporphyrins has been synthesized and structurally characterized. Fluoride abstraction from SbF6 (-) and BF4 (-) resulted in the synthesis of the μ-fluoro complexes of ethane- and ethene-bridged diiron(III) bisporphyrins. Two such complexes were structurally characterized, which revealed a single fluoro bridge between two iron centers with a remarkably bent Fe-F-Fe unit. Although isoelectronic with the μ-hydroxo complexes, the μ-fluoro species are quite divergent in terms of the electronic structure and properties. UV/Vis spectroscopy of the μ-fluoro complex exhibits a large redshift (ca. 18 nm) of the Soret band in comparison to their μ-hydroxo analog. Combined analysis by single crystal X-ray structure determination and Mössbauer and (1) H NMR spectroscopy revealed the presence of two equivalent iron(III) centers in the μ-fluoro complexes in both solid and solution phases. In contrast, the iron(III) centers of the μ-hydroxo complexes are known to be inequivalent. Variable-temperature magnetic studies show a weak antiferromagnetic interaction between the iron(III) centers of the μ-fluoro complexes with coupling constants (J) ranging from -33 to -40 cm(-1) . The experimental results were further supported by DFT calculations. PMID:27304611

  4. CANMET Gasifier Liner Coupon Material Test Report

    SciTech Connect

    Mark Fitzsimmons; Dave Grimmett; Bryan McEnerney

    2007-01-31

    This report provides detailed test results consisting of test data and post-test inspections from Task 1 ''Cooled Liner Coupon Development and Test'' of the project titled ''Development of Technologies and Capabilities for Coal Energy Resources--Advanced Gasification Systems Development (AGSD)''. The primary objective of this development and test program is to verify that ceramic matrix composite (CMC) liner materials planned for use in an advanced gasifier pilot plant will successfully withstand the environments in a commercial gasifier. Pratt & Whitney Rocketdyne (PWR) designed and fabricated the cooled liner test assembly article that was tested in a slagging gasifier at CANMET Energy Technology Center (CETC-O) in Ottawa, Ontario, Canada. The test program conducted in 2006 met the objective of operating the cooled liner test article at slagging conditions in a small scale coal gasifier at CETC-O for over the planned 100 hours. The test hardware was exposed to at least 30 high temperature excursions (including start-up and shut-down cycles) during the test program. The results of the testing has provided valuable information on gasifier startup and required cooling controls in steady state operation of future advanced gasifiers using similar liners. The test program also provided a significant amount of information in the areas of CMC materials and processing for improved capability in a gasifier environment and insight into CMC liner fabrication that will be essential for near-term advanced gasifier projects.

  5. Pocketing mechanics of SRM nozzle liner

    NASA Technical Reports Server (NTRS)

    Verderaime, V. S.

    1986-01-01

    A systems approach was adopted to study the pocketing phenomena on a solid rocket nozzle liner. The classical thermoelastic analysis was used to identify marginally strained regions on the composite liner erosion surface and at a depth coincident with the peak value of the across ply coefficient of thermal expansion. A failure criterion was introduced which included a thermal term and permitted failure assessment over the charred liner. The method was verified by satisfactory application to a reported related experiment. Liner pocketing mechanism was attributed to very localized material degradation caused during manufacturing process either by reduction of fiber strength and/or by concentration of resin volume fraction. Pocketing scenario over the degraged material was constructed with supporting formulation to predict size of fissures with respect to degraded material size and location in the liner and with burn time. Sensitivities of liner material parameters were determined to influence test programs designed to update mechanical data base of carbon cloth phenolic over the char temperature range.

  6. Time Dependent Effect of a Denture Cleanser on the Sorption and Solubility of Four Soft Liners-An Invitro Study

    PubMed Central

    Sudhapalli, Sruthikeerthi

    2016-01-01

    Introduction Soft liner materials, when used with ill fitting dentures, are constantly kept in a wet environment of either saliva or denture cleanser that affects their sorption and solubility. These inturn have detrimental effect on other properties. Aim To evaluate the influence of different exposure times of a commonly used denture cleanser on sorption and solubility of four soft liners. Materials and Methods Metal disc was fabricated to make the mould space for soft liner samples. Four materials were used, long term and short term acrylic liners; long term and short term silicone liners. Each of these were divided into four groups: first control group– all liners were kept in artificial saliva for entire period of study. Second group- liners were immersed daily in cleanser for 1 hour and then transferred to artificial saliva for rest of the day. Similarly samples of third and fourth groups were immersed in cleanser for 4 and 8 hours respectively and transferred to artificial saliva. Sorption and solubility tests were conducted and statistical analysis done. Statistical Analysis One-way ANOVA followed by Post-hoc Tukey’s test for pair wise comparisons was done. Significance was set at the probability level of p < 0.05. Results Solubility values of all groups were higher than the quoted ADA specifications. Conclusion Overall, silicones performed better than acrylics. Long term silicone was most stable. Short term acrylic was most unstable. The 8 hour immersion in denture cleanser caused significantly high sorption and solubility. PMID:27190940

  7. Prospects for x-ray polarimetry measurements of magnetic fields in magnetized liner inertial fusion plasmas

    SciTech Connect

    Lynn, Alan G. Gilmore, Mark

    2014-11-15

    Magnetized Liner Inertial Fusion (MagLIF) experiments, where a metal liner is imploded to compress a magnetized seed plasma may generate peak magnetic fields ∼10{sup 4} T (100 Megagauss) over small volumes (∼10{sup −10}m{sup 3}) at high plasma densities (∼10{sup 28}m{sup −3}) on 100 ns time scales. Such conditions are extremely challenging to diagnose. We discuss the possibility of, and issues involved in, using polarimetry techniques at x-ray wavelengths to measure magnetic fields under these extreme conditions.

  8. The Composition of Metals Bound to Class III Metallothionein (Phytochelatin and Its Desglycyl Peptide) Induced by Various Metals in Root Cultures of Rubia tinctorum.

    PubMed Central

    Maitani, T.; Kubota, H.; Sato, K.; Yamada, T.

    1996-01-01

    The induction of phytochelatins (PCs) and their desglycyl peptides (both are referred to as class III metallothionein [CIIIMT]) by exposure to various metals (Ag+, As3+, As5+, Cd2+, Cu2+, Ga3+, Hg2+, In3+, Ni2+, Pb2+, Pd2+, Se4+, and Zn2+) and the metal composition in the CIIIMTs were investigated in root cultures of Rubia tinctorum L. All of these metal species induced PCs to various degrees when analyzed by the postcolumn derivatization high-performance liquid chromatography method. The desglycyl peptides of PCs often were also present. However, only Ag, Cd, and Cu were bound to the CIIIMTs that they induced when analyzed by the high-performance liquid chromatography-inductively coupled plasma-atomic emission spectrometry method. Cu was also bound to the CIIIMTs induced by Ag+, As3+, and Cd2+. After Ag+ exposure, an Fe peak that may be of Fe-CIIIMT was also observed. However, most of the metal species studied were not bound to the CIIIMTs that they induced. PMID:12226248

  9. Heterogeneous catalytic oxidation of As(III) on nonferrous metal oxides in the presence of H2O2.

    PubMed

    Kim, Dong-hyo; Bokare, Alok D; Koo, Min suk; Choi, Wonyong

    2015-03-17

    The oxidation of As(III) (arsenite) to As(V) (arsenate), a critical pretreatment process for total arsenic removal, is easily achieved using chemical oxidation methods. Hydrogen peroxide (H2O2) is widely used as an environmentally benign oxidant but its practical use for the arsenite oxidation is limited by the strong pH dependence and slow oxidation kinetics. This study demonstrated that H2O2-induced oxidation of As(III) can be markedly enhanced in the presence of nonferrous metal oxides (e.g., WO3, TiO2, ZrO2) as a heterogeneous catalyst working over a wide pH range in ambient reaction conditions. In particular, TiO2 is an ideal catalyst because it is not only active and stable but also easily available and inexpensive. Although the photocatalytic oxidation of As(III) on TiO2 was intensively studied, the thermal catalytic activities of TiO2 and other nonferrous metal oxides for the arsenic oxidation have been little investigated. The heterogeneous oxidation rate increased with increasing the TiO2 surface area and [H2O2] and weakly depended on pH whereas the homogeneous oxidation by H2O2 alone was favored only at alkaline condition. The oxidation rate in the TiO2/H2O2 system was not reduced at all in the absence of dioxygen. It was not retarded at all by OH radical scavengers but markedly inhibited by hydroperoxyl radical scavengers. It is proposed that the surface complexation of H2O2 on TiO2 induces the generation of the surface hydroperoxyl radical through an inner-sphere electron transfer, which subsequently reacts with As(III). The catalytic activity of TiO2 was maintained without showing any sign of deactivation. The heterogeneous catalytic oxidation is proposed as a viable method for the preoxidation treatment of As(III)-contaminated water under ambient conditions. PMID:25695481

  10. Consequence analysis of a liner breach due to steam under the liner

    SciTech Connect

    HIMES, D.A.

    1999-06-01

    Radiological and toxicological consequences are estimated for a steam release from tank C-106 associated with a breach of the tank liner due to formation of steam under the liner after dry-out of the sludge layer in the tank. The consequences are shown to be well below the most restrictive risk guidelines.

  11. Performance of a Checkerboard Liner With Uncertain Impedances

    NASA Technical Reports Server (NTRS)

    Robinson, J. H.; Watson, W. R.

    2005-01-01

    The current fleet of large commercial aircraft has successfully achieved FAA noise certifications because of, in part, the successful application of uniform passive duct liner treatments to control engine system noise. One goal of NASA's engine system noise reduction program is to develop technologies to improve the sound absorbing properties of duct liner treatments so that they remain effective in modern turbo fan engines. One such technology being studied is checkerboard or periodic axially and circumferentially segmented liners. A preliminary assessment of the potential of this technology was conducted by applying uncertainties associated with manufacturing, installation, source structure, and tonal frequency to a liner developed using deterministic design methods and generating a measure of improvement with respect to a uniform liner subjected to the same uncertainties. Deterministic design and analysis of the candidate checkerboard liner showed that it obtains a 1.5 dB per duct aspect ratio improvement in liner attenuation over a similarly designed uniform liner. When uncertainties in liner impedances, source structure, and frequency are considered, the performance of the checkerboard liner drops off dramatically. The final results of this paper show that the candidate checkerboard liner has a less than 25 percent chance of outperforming the uniform liner when moderate levels of uncertainty are considered. It is important to note that this study did not include the effects of mean flow on liner performance and, more important to note, that as a gradient based optimization process was used to design the checkerboard liner, it is almost certain that a global optimal design was not found for the candidate checkerboard liner. Had it been possible to find a better deterministically performing checkerboard liner, the probability that this candidate liner would outperform the uniform liner would certainly have been higher.

  12. Development of a fracture control method for composite tanks with load sharing liners

    NASA Technical Reports Server (NTRS)

    Bixler, W. D.

    1973-01-01

    This experimental program was undertaken to establish a fracture control method for composite tanks with load sharing liners. Uniaxial specimens containing surface flaws were loaded to failure (static fractured) and cycled to failure and the results were compared with burst tests and cyclic life tests of composite tanks having surface flaws present in the load sharing metal liners. The liner materials investigated were Inconel X750 STA, 2219-T62 aluminum and cryostretched 301 stainless steel at room temperature and at 78 K (-320 F) in liquid nitrogen. Differences were observed in comparing the uniaxial and tank test results. These differences should be resolved if an adequate fracture control method is to be developed.

  13. Calculation of the dynamics of a shaped liner for quasispherical plasma compression

    NASA Astrophysics Data System (ADS)

    Kozlov, N. P.; Kurtmullaev, R. K.; Semenov, V. N.; Khvesyuk, V. I.; Yaminskii, A. V.

    Thermonuclear synthesis is initiated by a method which utilizes compression and retention of plasma in a magnetic field with the aid of a heavy metal liner. Megagauss magnetic fields and plasma pressures of ten billion to one hundred billion N/sqm can be achieved in doing so. The versions include an approach based on the idea of quasispherical compression of a compact toroidal structure with closed magnetic field by a liner. The plasma toroid with closed field is injected from a formation chamber into the cavity of a liner which is initially cylindrical. In the general case, a central conductor is positioned on the axis of the system in order to create a stabilizing toroidal field when a Tokomak type of toroid structure is used.

  14. Validation of structural analysis methods using burner liner cyclic rig test data

    NASA Technical Reports Server (NTRS)

    Thompson, R.

    1983-01-01

    The objectives of the hot section technology (HOST) burner liner cyclic rig test program are basically threefold: (1) to assist in developing predictive tools needed to improve design analyses and procedures for the efficient and accurate prediction of burner liner structural response; (2) to calibrate, evaluate and validate these predictive tools by comparing the predicted results with the experimental data generated in the tests; and (3) to evaluate existing as well as advanced temperature and strain measurement instrumentation, both contact and noncontact, in a simulated engine cycle environment. The data generated will include measurements of the thermal environment (metal surface temperatures) as well as structural (strain) and life (fatigue) responses of simulated burner liners and specimens under controlled boundary and operating conditions. These data will be used to calibrate, compare and validate analytical theories, methodologies and design procedures, as well as improvements in them, for predicting liner temperatures, stress-strain responses and cycles to failure. Comparison of predicted results with experimental data will be used to show where the predictive theories, etc. need improvements. In addition, as the predictive tools, as well as the tests, test methods, and data acquisition and reduction techniques, are developed and validated, a proven, integrated analysis/experiment method will be developed to determine the cyclic life of a simulated burner liner.

  15. Liner-less Tanks for Space Application - Design and Manufacturing Considerations

    NASA Technical Reports Server (NTRS)

    Jones, Brian H.; Li, Min-Chung

    2003-01-01

    Composite pressure vessels, used extensively for gas and fuel containment in space vehicles, are generally constructed with a metallic liner, while the fiber reinforcement carries the major portion of the pressure-induced load. The design is dominated by the liner s low strain at yield since the reinforcing fibers cannot operate at their potential load-bearing capability without resorting to pre-stressing (or autofrettaging). An ultra high-efficiency pressure vessel, which operates at the optimum strain capability of the fibers, can be potentially achieved with a liner-less construction. This paper discusses the design and manufacturing challenges to be overcome in the development of such a pressure vessel. These include: (1) gas/liquid containment and permeation, (2) design and structural analysis, and (3) manufacturing process development. The paper also presents the development and validation tests on a liner-less pressure vessel developed by Kaiser Compositek Inc. (KCI). It should be noted that KCI s liner-less tank exhibits a highly controlled leak-before-burst mode. This feature results in a structure having the highest level of safety.

  16. Composite liner design to maximize the shock pressure beyond megabars

    SciTech Connect

    Lee, H.

    1996-09-01

    Among the solid liners made of a single material which are imploded onto a target under the same driving condition, the aluminum liner produces the highest shock pressure. The authors propose the composite liner design which can increase the shock pressure several times over the best performance obtainable from an aluminum liner. They have also developed a general formulation to optimize the composite liner design for any driving current, and derived a set of very useful scaling relations. Finally, the authors present some 1-D simulations of the optimal composite liners to be fielded at Pegasus and Procyon in the upcoming megabar experiments.

  17. Tokamak with liquid metal toroidal field coil

    DOEpatents

    Ohkawa, Tihiro; Schaffer, Michael J.

    1981-01-01

    Tokamak apparatus includes a pressure vessel for defining a reservoir and confining liquid therein. A toroidal liner disposed within the pressure vessel defines a toroidal space within the liner. Liquid metal fills the reservoir outside said liner. Electric current is passed through the liquid metal over a conductive path linking the toroidal space to produce a toroidal magnetic field within the toroidal space about the major axis thereof. Toroidal plasma is developed within the toroidal space about the major axis thereof.

  18. Plasma-Jet-Driven Magneto-Inertial Fusion (PJMIF): Physics and Design for a Plasma Liner Formation Experiment

    NASA Astrophysics Data System (ADS)

    Hsu, Scott; Cassibry, Jason; Witherspoon, F. Douglas

    2014-10-01

    Spherically imploding plasma liners are a potential standoff compression driver for magneto-inertial fusion, which is a hybrid of and operates in an intermediate density between those of magnetic and inertial fusion. We propose to use an array of merging supersonic plasma jets to form a spherically imploding plasma liner. The jets are to be formed by pulsed coaxial guns with contoured electrodes that are placed sufficiently far from the location of target compression such that no hardware is repetitively destroyed. As such, the repetition rate can be higher (e.g., 1 Hz) and ultimately the power-plant economics can be more attractive than most other MIF approaches. During the R&D phase, a high experimental shot rate at reasonably low cost (e.g., < 1 k/shot) may be achieved with excellent diagnostic access, thus enabling a rapid learning rate. After some background on PJMIF and its prospects for reactor-relevant energy gain, this poster describes the physics objectives and design of a proposed 60-gun plasma-liner-formation experiment, which will provide experimental data on: (i) scaling of peak liner ram pressure versus initial jet parameters, (ii) liner non-uniformity characterization and control, and (iii) control of liner profiles for eventual gain optimization.

  19. Sealing leaks in geomembrane liners using electrophoresis

    SciTech Connect

    Darilek, G.T.; Corapcioglu, M.Y.; Yeung, A.T.

    1996-06-01

    An innovative method was demonstrated to seal leaks in geomembrane liners by attracting clay particles to the leaks using electrophoresis. Electrophoresis is the movement of electrically charged particles suspended in a liquid by the action of an electric field. A direct-current voltage impressed across the liner causes electrical current to flow through the leaks. The current produces a strong electric field at leaks. When a clay slurry is dispersed into the liquid in the impoundment, electrophoresis attracts the clay particles to the leaks, thereby sealing them. The method can seal leaks in liquid impoundments without removing the liquid or locating or accessing the leaks. The laboratory and full-scale test results were remarkable in that electrophoresis sealed the leaks completely when a layer of geofabric was under the liner, and electrophoresis reduced the leakage rate through holes as large as 10 mm in diameter by a factor of 1,600 in the field test with gravel under the liner, and by a factor of 1,667 in the laboratory basin with geonet under the liner.

  20. Use of FGD as an impervious liner

    SciTech Connect

    Wolfe, W.E.; Butalia, T.S.

    1998-07-01

    Increasing generation of coal combustion products (CCPs), particularly flue gas desulfurization (FGD) material, has led utilities to look for beneficial uses of these products. This paper presents one such utilization application of CCPs, i.e., the use of FGD material as an impervious liner for ponds and lagoons. The construction of a full scale lagoon using compacted FGD as a liner is presented. The project was undertaken primarily to address two critical questions, (1) what is the quality of water that permeates through an FGD liner and (2) what is the quantity of water permeating through a field compacted FGD fill of known thickness? The effects of construction processes on the behavior of compacted FGD are evaluated. The monitoring of the performance of the lagoon liner is discussed. Preliminary results indicate that the permeability of the field compacted FGD liner is reducing with time and is approaching the EPA recommended value of 1 x 10{sup {minus}7} cm/sec for waste containment facilities.

  1. Use of FGD as an impervious liner

    SciTech Connect

    Wolfe, W.E.; Butalia, T.S.

    1998-04-01

    Increasing generation of coal combustion products (CCPs), particularly flue gas desulfurization (FGD) material, has led utilities to look for beneficial uses of these products. This paper presents one such utilization application of CCPs, i.e., the use of FGD material as an impervious liner for ponds and lagoons. The construction of a full scale lagoon using compacted FGD as a liner is presented. The project was undertaken primarily to address two critical questions, (1) what is the quality of water that permeates through an FGD liner and (2) what is the quantity of water permeating through a field compacted FGD fill of known thickness? The effects of construction processes on the behavior of compacted FGD are evaluated. The monitoring of the performance of the lagoon liner is discussed. Preliminary results indicate that the permeability of the field compacted FGD liner is reducing with time and is approaching the EPA recommended value of 1x10{sup -7} cm/sec for waste containment facilities.

  2. Contaminant transport in organophilic waste deposit liners

    SciTech Connect

    Stockmeyer, M.R.; Madsen, F.T.; Kahr, G.

    1995-12-31

    The advective transport and diffusive transport of phenol through a soil liner material improve with organophilic bentonites was studied. The results were compared with the transport of phenol through the unimproved soil, a silty sand with a natural clay minerals content of approximately 5%, and through samples which were blended with a common calcium bentonite. With an increasing amount of added organophilic bentonite the adsorption capacity of the liner material and the contaminant retention increase. The diffusive transport of phenol is significantly retarded in the presence of organophilic bentonites, whereas the addition of a common hydrophilic calcium bentonite to the liner material only reduces the hydraulic permeability. There is little contaminant retention due to a low adsorption capacity for phenol of the hydrophilic bentonite. The diffusion is independent on the permeability of a liner material. In the appendix, the significance and the velocity of the hydraulic and diffusive contaminant transport of phenol as an organic test compound in a mineral sealing layer were studied. In a natural, hydrophilic, 1 m-thick liner, diffusion was calculated to be the faster transport mechanism. In the presence of organophilic bentonites the diffusive transport of phenol was found to be considerably hindered. 17 refs., 8 figs., 5 tabs.

  3. Resolution and analysis of the components in dual emission of mixed-chelate/ortho-metalate complexes of iridium(III)

    SciTech Connect

    Wilde, A.P.; King, K.A.; Watts, R.J. )

    1991-01-24

    Spectral resolutions of the two components in dual emissions for four mixed-chelate/ortho-metalated complexes of Ir(III) are reported. Resolution of the component emissions from samples of the complexes Ir(bzq){sub 2}(bpy){sup +} and Ir(bzq){sub 2}(phen){sup +} (bzq = benzo(h)quinoline, bpy = 2,2{prime}-bipyridine, phen = 1,10-phenanthroline) in rigid glasses at 77 K has been achieved by time-resolved emission spectroscopy. In each case the lower energy emissions component is assigned to a metal-to-ligand charge-transfer excited state associated with the chelating ligand and the higher energy component to a MLCT excited state associated with the ortho-metalating bzq ligand. Component in the dual emissions of Ir(ppy){sub 2}(bpy){sup +} and Ir(ppy){sub 2}(phen){sup +} (ppy = 2-phenylpyridine) are too similar in their lifetimes to permit full resolution of the two emissions by time-resolved emission spectroscopy when both components are populated by 337-nm excitation.

  4. Drag Measurements of Porous Plate Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Wolter, John D.

    2005-01-01

    This paper presents the results of direct drag measurements on a variety of porous plate acoustic liners. The existing literature describes numerous studies of drag on porous walls with injection or suction, but relatively few of drag on porous plates with neither injection nor suction. Furthermore, the porosity of the porous plate in existing studies is much lower than typically used in acoustic liners. In the present work, the acoustic liners consisted of a perforated face sheet covering a bulk acoustic absorber material. Factors that were varied in the experiment were hole diameter, hole pattern, face sheet thickness, bulk material type, and size of the gap (if any) between the face sheet and the absorber material.

  5. Quartz lamp thermocycling rig for combustion liners

    SciTech Connect

    Pfeifer, G.D.

    1986-01-01

    Improved combustor liner durability is a major design objective for advanced combustors. Combinations of low cycle fatigue, creep, oxidation and crack propagation are the damage mechanisms that reduce durability. Each of these mechanisms is a consequence of cyclic thermal loading. Closely controlled rig tests can simulate these damage mechanisms. Although rig testing requires duplicating the actual thermal strain range on a full size liner, it is economically more attractive than full-engine testing. A suitable rig for controlled cyclic thermal loading of large size cylindrical test specimens is developed using a 672 KW electric quartz lamp radiant heat source. The design objectives, operational features and development shake-down test results are presented in this paper. The development discusses deals specifically with combustor liner test specimens. The rig is also suitable for high temperature testing of large advanced material specimens including composite ceramics.

  6. Oxidation behavior of Cr(III) during thermal treatment of chromium hydroxide in the presence of alkali and alkaline earth metal chlorides.

    PubMed

    Mao, Linqiang; Gao, Bingying; Deng, Ning; Liu, Lu; Cui, Hao

    2016-02-01

    The oxidation behavior of Cr(III) during the thermal treatment of chromium hydroxide in the presence of alkali and alkaline earth metal chlorides (NaCl, KCl, MgCl2, and CaCl2) was investigated. The amounts of Cr(III) oxidized at various temperatures and heating times were determined, and the Cr-containing species in the residues were characterized. During the transformation of chromium hydroxide to Cr2O3 at 300 °C approximately 5% of the Cr(III) was oxidized to form intermediate compounds containing Cr(VI) (i.e., CrO3), but these intermediates were reduced to Cr2O3 when the temperature was above 400 °C. Alkali and alkaline earth metals significantly promoted the oxidation of Cr(III) during the thermal drying process. Two pathways were involved in the influences the alkali and alkaline earth metals had on the formation of Cr(VI). In pathway I, the alkali and alkaline earth metals were found to act as electron transfer agents and to interfere with the dehydration process, causing more intermediate Cr(VI)-containing compounds (which were identified as being CrO3 and Cr5O12) to be formed. The reduction of intermediate compounds to Cr2O3 was also found to be hindered in pathway I. In pathway II, the alkali and alkaline earth metals were found to contribute to the oxidation of Cr(III) to form chromates. The results showed that the presence of alkali and alkaline earth metals significantly increases the degree to which Cr(III) is oxidized during the thermal drying of chromium-containing sludge.

  7. Electrochemical Instability of Phosphonate-Derivatized, Ruthenium(III) Polypyridyl Complexes on Metal Oxide Surfaces.

    PubMed

    Hyde, Jacob T; Hanson, Kenneth; Vannucci, Aaron K; Lapides, Alexander M; Alibabaei, Leila; Norris, Michael R; Meyer, Thomas J; Harrison, Daniel P

    2015-05-13

    The oxidative stability of the molecular components of dye-sensitized photoelectrosynthesis cells for solar water splitting remains to be explored systematically. We report here the results of an electrochemical study on the oxidative stability of ruthenium(II) polypyridyl complexes surface-bound to fluorine-doped tin oxide electrodes in acidic solutions and, to a lesser extent, as a function of pH and solvent with electrochemical monitoring. Desorption occurs for the Ru(II) forms of the surface-bound complexes with oxidation to Ru(III) enhancing both desorption and decomposition. Based on the results of long-term potential hold experiments with cyclic voltammetry monitoring, electrochemical oxidation to Ru(III) results in slow decomposition of the complex by 2,2'-bipyridine ligand loss and aquation and/or anation. A similar pattern of ligand loss was also observed for a known chromophore-catalyst assembly for both electrochemical water oxidation and photoelectrochemical water splitting. Our results are significant in identifying the importance of enhancing chromophore stability, or at least transient stability, in oxidized forms in order to achieve stable performance in aqueous environments in photoelectrochemical devices. PMID:25871342

  8. Lifecycle Verification of Tank Liner Polymers

    SciTech Connect

    Anovitz, Lawrence {Larry} M; Smith, Barton

    2014-03-01

    This report describes a method that was developed for the purpose of assessing the durability of thermoplastic liners used in a Type IV hydrogen storage tank during the tank s expected service life. In the method, a thermoplastic liner specimen is cycled between the maximum and minimum expected working temperatures while it is differentially pressurized with high-pressure hydrogen gas. The number of thermal cycling intervals corresponds to those expected within the tank s design lifetime. At prescribed intervals, hydrogen permeation measurements are done in situ to assess the ability of the liner specimen to maintain its hydrogen barrier properties and to model its permeability over the tank lifetime. Finally, the model is used to assess whether the steady-state leakage rate in the tank could potentially exceed the leakage specification for hydrogen fuel cell passenger vehicles. A durability assessment was performed on a specimen of high-density polyethylene (HDPE) that is in current use as a tank liner. Hydrogen permeation measurements were performed on several additional tank liner polymers as well as novel polymers proposed for use as storage tank liners and hydrogen barrier materials. The following technical barriers from the Fuel Cell Technologies Program MYRDD were addressed by the project: D. Durability of on-board storage systems lifetime of at least 1500 cycles G. Materials of construction vessel containment that is resistant to hydrogen permeation M. Lack of Tank Performance Data and Understanding of Failure Mechanisms And the following technical targets1 for on-board hydrogen storage systems R&D were likewise addressed: Operational cycle life (1/4 tank to full) FY 2017: 1500 cycles; Ultimate: 1500 cycles Environmental health & safety Permeation and leakage: Meets or exceeds applicable standards Loss of useable H2: FY 2017: 0.05 g/h/kg H2; Ultimate: 0.05 g/h/kg H2

  9. Burner liner thermal/structural load modelling

    NASA Technical Reports Server (NTRS)

    Maffeo, R. J.

    1984-01-01

    A serious problem exists interfacing the output temperatures and temperature gradients from either the heat transfer codes or engine tests with the input to stress analysis codes. A thermal load transfer code was developed and was used in conjunction with a three-dimensional model of a combustor liner for verification. The 3D heat transfer and stress analysis models of combustor liners and turbine blades were used to validate the mapped temperature produced by the transfer module. Verification cases were made for both finite element and finite difference heat transfer codes. A user manual for the code was written and is available.

  10. Acoustic Panel Liner for an Engine Nacelle

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Nark, Douglas M. (Inventor); Ayle, Earl (Inventor); Ichihashi, Fumitaka (Inventor)

    2016-01-01

    An acoustic panel liner includes a face sheet, back plate, and liner core positioned there-between, which may be used in an engine nacelle. Elongated chambers contain variable amounts of septa at a calibrated depth or depths. The septa may have varying DC flow resistance. The chambers may have a hexagonal or other polygonal cross sections. The septa, such as mesh caps, may be bonded to an inner wall of a corresponding chamber. The insertion depths may be the same or different. If different, the pattern of distribution of the depths may be randomized.

  11. Advanced liner-cooling techniques for gas turbine combustors

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Riddlebaugh, S. M.

    1985-01-01

    Component research for advanced small gas turbine engines is currently underway at the NASA Lewis Research Center. As part of this program, a basic reverse-flow combustor geometry was being maintained while different advanced liner wall cooling techniques were investigated. Performance and liner cooling effectiveness of the experimental combustor configuration featuring counter-flow film-cooled panels is presented and compared with two previously reported combustors featuring: splash film-cooled liner walls; and transpiration cooled liner walls (Lamilloy).

  12. Structural response of an advanced combustor liner: Test and analysis

    NASA Technical Reports Server (NTRS)

    Moorhead, Paul E.; Thompson, Robert L.; Tong, M.; Higgins, M.

    1987-01-01

    An advanced (segmented) combustor liner supplied by Pratt and Whitney Aircraft was tested in the structural component test rig at Lewis Research Center. It was found that the segmented liner operated at much lower temperatures than the conventional liner (about 400 F lower) for the same heat flux. At the lower temperatures and low thermal gradients, little distortion to the segments was observed. The operating conditions were not severe enough to distort or damage the segmented liner.

  13. Assessing liner performance using on-farm milk meters.

    PubMed

    Penry, J F; Leonardi, S; Upton, J; Thompson, P D; Reinemann, D J

    2016-08-01

    The primary objective of this study was to quantify and compare the interactive effects of liner compression, milking vacuum level, and pulsation settings on average milk flow rates for liners representing the range of liner compression of commercial liners. A secondary objective was to evaluate a methodology for assessing liner performance that can be applied on commercial dairy farms. Eight different liner types were assessed using 9 different combinations of milking system vacuum and pulsation settings applied to a herd of 80 cows with vacuum and pulsation conditions changed daily for 36d using a central composite experimental design. Liner response surfaces were created for explanatory variables milking system vacuum (Vsystem) and pulsator ratio (PR) and response variable average milk flow rate (AMF=total yield/total cups-on time) expressed as a fraction of the within-cow average flow rate for all treatments (average milk flow rate fraction, AMFf). Response surfaces were also created for between-liner comparisons for standardized conditions of claw vacuum and milk ratio (fraction of pulsation cycle during which milk is flowing). The highest AMFf was observed at the highest levels of Vsystem, PR, and overpressure. All liners showed an increase in AMF as milking conditions were changed from low to high standardized conditions of claw vacuum and milk ratio. Differences in AMF between liners were smallest at the most gentle milking conditions (low Vsystem and low milk ratio), and these between-liner differences in AMF increased as liner overpressure increased. Differences were noted with vacuum drop between Vsystem and claw vacuum depending on the liner venting system, with short milk tube vented liners having the greater vacuum drop than mouthpiece chamber vented liners. The accuracy of liner performance assessment in commercial parlors fitted with milk meters can be improved by using a central composite experimental design with a repeated center point treatment

  14. A Nanoscale Multiresponsive Luminescent Sensor Based on a Terbium(III) Metal-Organic Framework.

    PubMed

    Dang, Song; Wang, Ting; Yi, Feiyan; Liu, Qinghui; Yang, Weiting; Sun, Zhong-Ming

    2015-08-01

    A nanoscale terbium-containing metal-organic framework (nTbL), with a layer-like structure and [H2 NMe2 ](+) cations located in the framework channels, was synthesized under hydrothermal conditions. The structure of the as-prepared sample was systematically confirmed by powder XRD and elemental analysis; the morphology was characterized by field-emission SEM and TEM. The photoluminescence studies revealed that rod-like nTbL exhibited bright-green emission, corresponding to (5)D4 →(7)FJ (J=6-3) transitions of the Tb(3+) ion under excitation. Further sensing measurements revealed that as-prepared nTbL could be utilized as a multiresponsive luminescent sensor, which showed significant and exclusive detection ability for Fe(3+) ions and phenylmethanol. These results highlight the practical applications of lanthanide-containing metal-organic frameworks as fluorescent probes.

  15. Hot subdwarf stars in close-up view. III. Metal abundances of subdwarf B stars

    NASA Astrophysics Data System (ADS)

    Geier, S.

    2013-01-01

    Context. Hot subdwarf B stars (sdBs) are considered to be core helium-burning stars with very thin hydrogen envelopes situated on or near the extreme horizontal branch. The formation of sdBs is still unclear as well as the chemical composition of their atmospheres. The observed helium depletion is attributed to atmospheric diffusion. Metal abundances have been determined for about a dozen sdBs only resulting in puzzling patterns with enrichment of heavy metals and depletion of lighter ones. Aims: We present a detailed metal abundance analysis of 106 sdBs. Methods: From high resolution spectra we measured elemental abundances of up to 24 different ions per star. A semi-automatic analysis pipeline was developed to calculate and fit LTE models to a standard set of spectral lines. Results: A general trend of enrichment was found with increasing temperature for most of the heavier elements. The lighter elements like carbon, oxygen, and nitrogen are depleted and less affected by temperature. Although there is considerable scatter from star to star, the general abundance patterns in most sdBs are similar. State-of-the-art diffusion models predict such patterns and are in qualitative agreement with our results. However, the highest enrichments measured cannot be explained with these models. Peculiar line shapes of the strongest metal lines in some stars indicate vertical stratification to be present in the atmospheres. Such effects are not accounted for in current diffusion models and may be responsible for some of the yet unexplained abundance anomalies. Tables A.1-A.3 are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/549/A110

  16. THE NATURE OF LINER-LIKE EMISSION IN RED GALAXIES

    SciTech Connect

    Yan Renbin; Blanton, Michael R.

    2012-03-01

    Passive red galaxies frequently contain warm ionized gas and have spectra similar to low-ionization nuclear emission-line regions (LINERs). Here we investigate the nature of the ionizing sources powering this emission, by comparing nuclear spectroscopy from the Palomar survey with larger aperture data from the Sloan Digital Sky Survey. We find the line emission in the majority of passive red galaxies is spatially extended; the H{alpha} surface brightness profile depends on radius r as r{sup -1.28}. We detect strong line ratio gradients with radius in [N II]/H{alpha}, [S II]/H{alpha}, and [O III]/[S II], requiring the ionization parameter to increase outward. Combined with a realistic gas density profile, this outward increasing ionization parameter convincingly rules out active galactic nuclei (AGNs) as the dominant ionizing source and strongly favors distributed ionizing sources. Sources that follow the stellar density profile can additionally reproduce the observed luminosity dependence of the line ratio gradient. Post-asymptotic giant branch stars provide a natural ionization source candidate, though they have an ionization parameter deficit. Velocity width differences among different emission lines disfavor shocks as the dominant ionization mechanism, and suggest that the interstellar medium in these galaxies contains multiple components. We conclude that the line emission in most LINER-like galaxies found in large-aperture (>100 pc) spectroscopy is not primarily powered by AGN activity and thus does not trace the AGN bolometric luminosity. However, they can be used to trace warm gas in these red galaxies.

  17. High temperature characteristics and solidification microstructures of dental metallic materials. Part III alloys for metal-bond porcelain.

    PubMed

    Nagasawa, Sakae; Yoshida, Takamitsu; Terashima, Nobuyoshi; Mizoguchi, Toshihide; Yagasaki, Hiroshi; Kamijo, Koichiro; Ito, Michio; Platt, Jeffrey A; Oshida, Yoshiki

    2005-03-01

    The thermal expansion rate, coefficient of thermal expansion, and high temperature strength of two types of commercially available alloy for metal-bond porcelain, KIK-HII (KIK) and Degubond-J2 (J2), were evaluated up to the liquidus point temperature using a thermo-mechanical analyzer. Furthermore, microstructure in the solid-liquid coexisting region was observed for evaluation. Our results revealed the following findings: 1. For KIK, solidus point was 1,209.3 +/- 3.2 degrees C, liquidus point was 1,308.3 +/- 7.10 degrees C, and melting expansion rate was 0.41+/- 0.16%. 2. For J2, solidus point was 1,198.3 +/- 0.6 degrees C, liquidus point was 1,253.0 +/- 4.4 degrees C, and melting expansion rate was 4.50 +/- 0.80%. 3. At high temperature, the mechanical characteristics of KIK greatly differed from those of J2. The risk of causing deformation during porcelain baking was suggested for KIK. Removal of segregation during casting was considered difficult in J2. PMID:15881221

  18. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of...

  19. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of...

  20. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of...

  1. Tank 241-AY-102 Secondary Liner Corrosion Evaluation - 14191

    SciTech Connect

    Boomer, Kayle D.; Washenfelder, Dennis J.; Johnson, Jeremy M.

    2014-01-07

    In October 2012, Washington River Protection Solutions, LLC (WRPS) determined that the primary tank of 241-AY-102 (AY-102) was leaking. A number of evaluations were performed after discovery of the leak which identified corrosion from storage of waste at the high waste temperatures as one of the major contributing factors in the failure of the tank. The propensity for corrosion of the waste on the annulus floor will be investigated to determine if it is corrosive and must be promptly removed or if it is benign and may remain in the annulus. The chemical composition of waste, the temperature and the character of the steel are important factors in assessing the propensity for corrosion. Unfortunately, the temperatures of the wastes in contact with the secondary steel liner are not known; they are estimated to range from 45 deg C to 60 deg C. It is also notable that most corrosion tests have been carried out with un-welded, stress-relieved steels, but the secondary liner in tank AY-102 was not stress-relieved. In addition, the cold weather fabrication and welding led to many problems, which required repeated softening of the metal to flatten secondary bottom during its construction. This flame treatment may have altered the microstructure of the steel.

  2. Interfacial oxide re-growth in thin film metal oxide III-V semiconductor systems

    SciTech Connect

    McDonnell, S.; Dong, H.; Hawkins, J. M.; Brennan, B.; Milojevic, M.; Aguirre-Tostado, F. S.; Zhernokletov, D. M.; Hinkle, C. L.; Kim, J.; Wallace, R. M.

    2012-04-02

    The Al{sub 2}O{sub 3}/GaAs and HfO{sub 2}/GaAs interfaces after atomic layer deposition are studied using in situ monochromatic x-ray photoelectron spectroscopy. Samples are deliberately exposed to atmospheric conditions and interfacial oxide re-growth is observed. The extent of this re-growth is found to depend on the dielectric material and the exposure temperature. Comparisons with previous studies show that ex situ characterization can result in misleading conclusions about the interface reactions occurring during the metal oxide deposition process.

  3. Sub-Chronic Oral Exposure to Iridium (III) Chloride Hydrate in Female Wistar Rats: Distribution and Excretion of the Metal

    PubMed Central

    Iavicoli, Ivo; Fontana, Luca; Bergamaschi, Antonio; Conti, Marcelo Enrique; Pino, Anna; Mattei, Daniela; Bocca, Beatrice; Alimonti, Alessandro

    2012-01-01

    Iridium tissue distribution and excretion in female Wistar rats following oral exposure to iridium (III) chloride hydrate in drinking water (from 1 to 1000 ng/ml) in a sub-chronic oral study were determined. Samples of urine, feces, blood and organs (kidneys, liver, lung, spleen and brain) were collected at the end of exposure. The most prominent fractions of iridium were retained in kidney and spleen; smaller amounts were found in lungs, liver and brain. Iridium brain levels were lower than those observed in other tissues but this finding can support the hypothesis of iridium capability to cross the blood brain barrier. The iridium kidney levels rose significantly with the administered dose. At the highest dose, important amounts of the metal were found in serum, urine and feces. Iridium was predominantly excreted via feces with a significant linear correlation with the ingested dose, which is likely due to low intestinal absorption of the metal. However, at the higher doses iridium was also eliminated through urine. These findings may be useful to help in the understanding of the adverse health effects, particularly on the immune system, of iridium dispersed in the environment as well as in identifying appropriate biological indices of iridium exposure. PMID:22942873

  4. Inductively Driven, 3D Liner Compression of a Magnetized Plasma to Megabar Energy Densities

    SciTech Connect

    Slough, John

    2015-02-01

    To take advantage of the smaller scale, higher density regime of fusion an efficient method for achieving the compressional heating required to reach fusion gain conditions must be found. What is proposed is a more flexible metallic liner compression scheme that minimizes the kinetic energy required to reach fusion. It is believed that it is possible to accomplish this at sub-megajoule energies. This however will require operation at very small scale. To have a realistic hope of inexpensive, repetitive operation, it is essential to have the liner kinetic energy under a megajoule which allows for the survivability of the vacuum and power systems. At small scale the implosion speed must be reasonably fast to maintain the magnetized plasma (FRC) equilibrium during compression. For limited liner kinetic energy, it becomes clear that the thinnest liner imploded to the smallest radius consistent with the requirements for FRC equilibrium lifetime is desired. The proposed work is directed toward accomplishing this goal. Typically an axial (Z) current is employed for liner compression. There are however several advantages to using a θ-pinch coil. With the θ-pinch the liner currents are inductively driven which greatly simplifies the apparatus and vacuum system, and avoids difficulties with the post implosion vacuum integrity. With fractional flux leakage, the foil liner automatically provides for the seed axial compression field. To achieve it with optimal switching techniques, and at an accelerated pace however will require additional funding. This extra expense is well justified as the compression technique that will be enabled by this funding is unique in the ability to implode individual segments of the liner at different times. This is highly advantageous as the liner can be imploded in a manner that maximizes the energy transfer to the FRC. Production of shaped liner implosions for additional axial compression can thus be readily accomplished with the modified power

  5. Chemical abundance analysis of symbiotic giants - III. Metallicity and CNO abundance patterns in 24 southern systems

    NASA Astrophysics Data System (ADS)

    Gałan, Cezary; Mikołajewska, Joanna; Hinkle, Kenneth H.; Joyce, Richard R.

    2016-01-01

    The elemental abundances of symbiotic giants are essential to address the role of chemical composition in the evolution of symbiotic binaries, to map their parent population, and to trace their mass transfer history. However, the number of symbiotic giants with fairly well determined photospheric composition is still insufficient for statistical analyses. This is the third in a series of papers on the chemical composition of symbiotic giants determined from high-resolution (R ˜ 50 000), near-infrared spectra. Here we present results for 24 S-type systems. Spectrum synthesis methods employing standard local thermal equilibrium analysis and atmosphere models were used to obtain photospheric abundances of CNO and elements around the iron peak (Fe, Ti, Ni, and Sc). Our analysis reveals metallicities distributed in a wide range from slightly supersolar ([Fe/H] ˜ +0.35 dex) to significantly subsolar ([Fe/H] ˜ -0.8 dex) but principally with near-solar and slightly subsolar metallicity ([Fe/H] ˜ -0.4 to -0.3 dex). The enrichment in 14N isotope, found in all these objects, indicates that the giants have experienced the first dredge-up. This was confirmed in a number of objects by the low 12C/13C ratio (5-23). We found that the relative abundance of [Ti/Fe] is generally large in red symbiotic systems.

  6. Diagnostics for the plasma liner experiment.

    PubMed

    Lynn, A G; Merritt, E; Gilmore, M; Hsu, S C; Witherspoon, F D; Cassibry, J T

    2010-10-01

    The goal of the Plasma Liner Experiment (PLX) is to explore and demonstrate the feasibility of forming imploding spherical "plasma liners" via merging high Mach number plasma jets to reach peak liner pressures of ∼0.1 Mbar using ∼1.5 MJ of initial stored energy. Such a system would provide HED plasmas for a variety of fundamental HEDLP, laboratory astrophysics, and materials science studies, as well as a platform for experimental validation of rad-hydro and rad-MHD simulations. It could also prove attractive as a potential standoff driver for magnetoinertial fusion. Predicted parameters from jet formation to liner stagnation cover a large range of plasma density and temperature, varying from n(i)∼10(16) cm(-3), T(e)≈T(i)∼1 eV at the plasma gun mouth to n(i)>10(19) cm(-3), T(e)≈T(i)∼0.5 keV at stagnation. This presents a challenging problem for the plasma diagnostics suite which will be discussed.

  7. Welded polypropylene liners for large descaling tanks

    NASA Technical Reports Server (NTRS)

    Abel, H. P.

    1971-01-01

    Liners for nitric and hydrofluoric acid tanks show no sign of deterioration after 18 months of continuous use. Each side of each edge of the polypropylene sheets is chamfered, and sheets are welded from both sides with polypropylene filler rod and a special hot-air welding torch.

  8. Membrane behavior of clay liner materials

    NASA Astrophysics Data System (ADS)

    Kang, Jong Beom

    Membrane behavior represents the ability of porous media to restrict the migration of solutes, leading to the existence of chemico-osmosis, or the flow of liquid in response to a chemical concentration gradient. Membrane behavior is an important consideration with respect to clay soils with small pores and interactive electric diffuse double layers associated with individual particles, such as bentonite. The results of recent studies indicate the existence of membrane behavior in bentonite-based hydraulic barriers used in waste containment applications. Thus, measurement of the existence and magnitude of membrane behavior in such clay soils is becoming increasingly important. Accordingly, this research focused on evaluating the existence and magnitude of membrane behavior for three clay-based materials that typically are considered for use as liners for waste containment applications, such as landfills. The three clay-based liner materials included a commercially available geosynthetic clay liner (GCL) consisting of sodium bentonite sandwiched between two geotextiles, a compacted natural clay known locally as Nelson Farm Clay, and compacted NFC amended with 5% (dry wt.) of a sodium bentonite. The study also included the development and evaluation of a new flexible-wall cell for clay membrane testing that was used subsequently to measure the membrane behaviors of the three clay liner materials. The consolidation behavior of the GCL under isotropic states of stress also was evaluated as a preliminary step in the determination of the membrane behavior of the GCL under different effective consolidation stresses.

  9. Diagnostics for the Plasma Liner Experiment

    SciTech Connect

    Lynn, A. G.; Merritt, E.; Gilmore, M.; Hsu, S. C.; Witherspoon, F. D.; Cassibry, J. T.

    2010-10-15

    The goal of the Plasma Liner Experiment (PLX) is to explore and demonstrate the feasibility of forming imploding spherical ''plasma liners'' via merging high Mach number plasma jets to reach peak liner pressures of {approx}0.1 Mbar using {approx}1.5 MJ of initial stored energy. Such a system would provide HED plasmas for a variety of fundamental HEDLP, laboratory astrophysics, and materials science studies, as well as a platform for experimental validation of rad-hydro and rad-MHD simulations. It could also prove attractive as a potential standoff driver for magnetoinertial fusion. Predicted parameters from jet formation to liner stagnation cover a large range of plasma density and temperature, varying from n{sub i}{approx}10{sup 16} cm{sup -3}, T{sub e}{approx_equal}T{sub i}{approx}1 eV at the plasma gun mouth to n{sub i}>10{sup 19} cm{sup -3}, T{sub e}{approx_equal}T{sub i}{approx}0.5 keV at stagnation. This presents a challenging problem for the plasma diagnostics suite which will be discussed.

  10. ALFALFA DISCOVERY OF THE NEARBY GAS-RICH DWARF GALAXY LEO P. III. AN EXTREMELY METAL DEFICIENT GALAXY

    SciTech Connect

    Skillman, Evan D.; Berg, Danielle A.; Olive, Keith A.; McQuinn, Kristen B. W. E-mail: berg@astro.umn.edu E-mail: kmcquinn@astro.umn.edu; and others

    2013-07-01

    We present KPNO 4 m and LBT/MODS spectroscopic observations of an H II region in the nearby dwarf irregular galaxy Leo P discovered recently in the Arecibo ALFALFA survey. In both observations, we are able to accurately measure the temperature sensitive [O III] {lambda}4363 line and determine a ''direct'' oxygen abundance of 12 + log(O/H) = 7.17 {+-} 0.04. Thus, Leo P is an extremely metal deficient (XMD) galaxy, and, indeed, one of the most metal deficient star-forming galaxies ever observed. For its estimated luminosity, Leo P is consistent with the relationship between luminosity and oxygen abundance seen in nearby dwarf galaxies. Leo P shows normal {alpha} element abundance ratios (Ne/O, S/O, and Ar/O) when compared to other XMD galaxies, but elevated N/O, consistent with the ''delayed release'' hypothesis for N/O abundances. We derive a helium mass fraction of 0.2509{sup +0.0184}{sub -0.0123}, which compares well with the WMAP + BBN prediction of 0.2483 {+-} 0.0002 for the primordial helium abundance. We suggest that surveys of very low mass galaxies compete well with emission line galaxy surveys for finding XMD galaxies. It is possible that XMD galaxies may be divided into two classes: the relatively rare XMD emission line galaxies which are associated with starbursts triggered by infall of low-metallicity gas and the more common, relatively quiescent XMD galaxies like Leo P, with very low chemical abundances due to their intrinsically small masses.

  11. Statistically Based Approach to Broadband Liner Design and Assessment

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M. (Inventor); Jones, Michael G. (Inventor)

    2016-01-01

    A broadband liner design optimization includes utilizing in-duct attenuation predictions with a statistical fan source model to obtain optimum impedance spectra over a number of flow conditions for one or more liner locations in a bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners having impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increasing weighting to specific frequencies and/or operating conditions. One or more broadband design approaches are utilized to produce a broadband liner that targets a full range of frequencies and operating conditions.

  12. Efficient generation of perfluoroalkyl radicals from sodium perfluoroalkanesulfinates and a hypervalent iodine(iii) reagent: mild, metal-free synthesis of perfluoroalkylated organic molecules.

    PubMed

    Sakamoto, Ryu; Kashiwagi, Hirotaka; Selvakumar, Sermadurai; Moteki, Shin A; Maruoka, Keiji

    2016-07-01

    This article describes an efficient method for the introduction of perfluoroalkyl groups into N-acrylamides, 2-isocyanides, olefins, and other heterocycles using perfluoroalkyl radicals that were generated from the reaction between sodium perfluoroalkanesulfinates and a hypervalent iodine(iii) reagent. This approach represents a simple, scalable perfluoroalkylation method under mild and metal-free conditions.

  13. Geosynthetic clay liners shrinkage under simulated daily thermal cycles.

    PubMed

    Sarabadani, Hamid; Rayhani, Mohammad T

    2014-06-01

    Geosynthetic clay liners are used as part of composite liner systems in municipal solid waste landfills and other applications to restrict the escape of contaminants into the surrounding environment. This is attainable provided that the geosynthetic clay liner panels continuously cover the subsoil. Previous case histories, however, have shown that some geosynthetic clay liner panels are prone to significant shrinkage and separation when an overlying geomembrane is exposed to solar radiation. Experimental models were initiated to evaluate the potential shrinkage of different geosynthetic clay liner products placed over sand and clay subsoils, subjected to simulated daily thermal cycles (60°C for 8 hours and 22°C for 16 hours) modelling field conditions in which the liner is exposed to solar radiation. The variation of geosynthetic clay liner shrinkage was evaluated at specified times by a photogrammetry technique. The manufacturing techniques, the initial moisture content, and the aspect ratio (ratio of length to width) of the geosynthetic clay liner were found to considerably affect the shrinkage of geosynthetic clay liners. The particle size distribution of the subsoil and the associated suction at the geosynthetic clay liner-subsoil interface was also found to have significant effects on the shrinkage of the geosynthetic clay liner.

  14. Geosynthetic clay liners shrinkage under simulated daily thermal cycles.

    PubMed

    Sarabadani, Hamid; Rayhani, Mohammad T

    2014-06-01

    Geosynthetic clay liners are used as part of composite liner systems in municipal solid waste landfills and other applications to restrict the escape of contaminants into the surrounding environment. This is attainable provided that the geosynthetic clay liner panels continuously cover the subsoil. Previous case histories, however, have shown that some geosynthetic clay liner panels are prone to significant shrinkage and separation when an overlying geomembrane is exposed to solar radiation. Experimental models were initiated to evaluate the potential shrinkage of different geosynthetic clay liner products placed over sand and clay subsoils, subjected to simulated daily thermal cycles (60°C for 8 hours and 22°C for 16 hours) modelling field conditions in which the liner is exposed to solar radiation. The variation of geosynthetic clay liner shrinkage was evaluated at specified times by a photogrammetry technique. The manufacturing techniques, the initial moisture content, and the aspect ratio (ratio of length to width) of the geosynthetic clay liner were found to considerably affect the shrinkage of geosynthetic clay liners. The particle size distribution of the subsoil and the associated suction at the geosynthetic clay liner-subsoil interface was also found to have significant effects on the shrinkage of the geosynthetic clay liner. PMID:24718363

  15. FE analysis of dynamic characteristics for mill's liners

    NASA Astrophysics Data System (ADS)

    Feng, Xianzhang; Cui, Yanmei; Jiang, Zhiqiang; Hou, Tao

    2009-07-01

    Slab side pressing is an online regulation width technology for continuous casting slab, the liner at the bottom of the framework under the larger impact force, it often can occurrence accident of liner Board broken during working of sizing press rolling mill. In order to analyze force distribution and its peak in the liner of rolling mill during side pressing, liner dynamics model is established using nonlinear function of finite element software, and the contact mode is established for liner and wheel by Hertz law theory. It yields the relations between maximal stress and tap hole in the liner, the design scheme is extracted for improving condition of linerboard's stress, and the calculated results were much inosculated with the measured values. The studied results indicated that the liner's life gets improve obviously in field.

  16. Minimal backside surface changes observed in retrieved acetabular liners.

    PubMed

    Akbari, Abtin; Roy, Marcel E; Whiteside, Leo A; Katerberg, Brian J; Schnettgoecke, Daniel J

    2011-08-01

    Modular polyethylene liners offer versatility in total hip arthroplasty, but the locking mechanism may allow micromotion and backside wear. We evaluated the backside surface of 56 retrieved acetabular liners (mean 5.54 years in vivo, range 0.003-13.1 years) to determine whether damage correlated with liner age in vivo, patient factors associated with higher activity, and polyethylene quality. Half of the liners exhibited minimal damage, half exhibited no damage and none exhibited severe damage. Backside damage significantly correlated only to liner age in vivo. Ten of the 28 liners revised for osteolysis exhibited no backside damage, but the osteolytic cysts were peripheral and did not originate from screw holes. The results suggest that modular polyethylene liners in a porous titanium-coated shell with screw holes can be designed such that clinically significant backside wear is minimal. PMID:20875939

  17. Liner Stability Experiments at Pegasus: Diagnostics and Experimental Results

    SciTech Connect

    Clark, D.A.; Morgan, D.V.; Rodriguez, G.

    1998-10-18

    A series of experiments to compare imploding liner performance with magneto-hydrodynamic (MHD) modeling has been performed at the Los Alamos National Laboratory Pegasus II pulse power machine. Liner instability growth originating from initial perturbations machined into the liner has been observed with high resolution. Three major diagnostics were used: radiography, Velocity Interferometer for a Surface of Any Reflector (VISAR), and fiber optic impact pins. For radiography, three flash x-ray units were mounted radially to observe liner shape at three different times during the implosion. Liner velocity was measured continuously with the VISAR for the entire distance traveled in two experiments. Optical impact pins provide a high-resolution measure of liner symmetry and shape near the end of travel. Liner performance has compared well with predictions.

  18. Proteomic analysis in Daphnia magna exposed to As(III), As(V) and Cd heavy metals and their binary mixtures for screening potential biomarkers.

    PubMed

    Le, Thai-Hoang; Lim, Eun-Suk; Hong, Nam-Hui; Lee, Sung-Kyu; Shim, Yon Sik; Hwang, Jin Rae; Kim, Yang-Hoon; Min, Jiho

    2013-11-01

    In this study, the effects of three widespread heavy metals, As(III), As(V) and Cd, and their binary mixtures on the proteomic profile in D. magna were examined to screen novel protein biomarkers using the two-dimensional gel electrophoresis method (2DE). Ten 20d daphnia were exposed to the LC20 concentrations for each of a total of 8 treatments, including the control, As(III), As(V), Cd, [As(III)+As(V)], [As(III)+Cd], [As(V)+Cd], and [As(III), As(V), Cd], for 24h before protein isolation. Three replicates were performed for each treatment. These protein samples were employed for 2DE experiments with a pH gradient gel strip from pH 3 to pH 10. The protein spots were detected by a silver staining process and their intensities were analyzed by Progenesis software to discover the differentially expressed proteins (DEPs) in response to each heavy metal. A total of 117 differentially expressed proteins (DEPs) were found in daphnia responding to the 8 treatments and mapped onto a 2D proteome map, which provides some information of the molecular weight (MW) and pI value for each protein. All of these DEPs are considered as potential candidates for protein biomarkers in D. magna for detecting heavy metals in the aquatic ecosystem. Comparing the proteomic results among these treatments suggested that exposing D. magna to binary mixtures of heavy metals may result in some complex interactive molecular responses within them, rather than just the simple sum of the proteomic profiles of the individual chemicals, (As(III), As(V), and Cd).

  19. Medium-term results of cementation of a highly cross-linked polyethylene liner into a well-fixed acetabular shell in revision hip arthroplasty.

    PubMed

    Lim, Seung-Jae; Lee, Keun-Ho; Park, Shin-Hyung; Park, Youn-Soo

    2014-03-01

    The present study was undertaken to document outcomes of cementation of a highly cross-linked polyethylene (PE) liner into a well-fixed acetabular metal shell in 36 hips. All operations were performed by a single surgeon using only one type of liner. Patients were followed for a mean of 6.1 years (range, 3-8 years). Mean Harris hip score improved from 58 points preoperatively to 91 points postoperatively. There were no cases of PE liner dislodgement or progressive osteolysis. 1 hip (2.8%) required revision surgery for acetabular cup loosening with greater trochanteric fracture. Complications included 1 peroneal nerve palsy and 1 dislocation. The results of this study and previous reports demonstrated that cementation of highly cross-linked PE liner into well-fixed metal shell could provide good midterm durability.

  20. Coprecipitation of arsenate with metal oxides. 2. Nature, mineralogy, and reactivity of iron(III) precipitates.

    PubMed

    Violante, Antonio; Del Gaudio, Stefania; Pigna, Massimo; Ricciardella, Mariarosaria; Banerjee, Dipanjan

    2007-12-15

    Coprecipitation of arsenic with iron or aluminum occurs in natural environments and is a remediation technology used to remove this toxic metalloid from drinking water and hydrometallurgical solutions. In this work, we studied the nature, mineralogy, and reactivity toward phosphate of iron-arsenate coprecipitates formed at As(V)/Fe(III) molar ratios (R) of 0, 0.01, or 0.1 and at pH 4.0, 7.0, and 10.0 aged for 30 or 210 days at 50 degrees C and studied the desorption of arsenate. At R = 0, goethite and hematite (with ferrihydrite at pH 4.0 and 7.0) crystallized, whereas at R = 0.01, the formation of ferrihydrite increased and hematite crystallization was favored over goethite. In some samples, the morphology of hematite changed from rounded platy crystals to ellipsoids. At R = 0.1, ferrihydrite formed in all the coprecipitates and remained unchanged even after 210 days of aging. The surface area and chemical composition of the precipitates were affected by pH, R, and aging. Chemical dissolution of the samples showed that arsenate was present mainly in ferrihydrite, but at R = 0.01, it was partially incorporated into the structures of crystalline Fe oxides. The sorption of phosphate on to the coprecipitates was affected not only by the mineralogy and surface area of the samples but also by the amounts of arsenate present in the oxides. The samples formed at pH 4.0 and 7.0 and at R = 0.1 sorbed lower amounts of phosphate than the precipitates obtained at R = 0 or 0.01, despite the former having a larger surface area and showing only a presence of short-range ordered materials. This is mainly due to the fact that in the coprecipitates at R = 0.1 arsenate occupied many sorption sites, thus preventing phosphate sorption. Less than 20% of the arsenate present in the coprecipitates formed at R = 0.1 was removed by phosphate and more from the samples synthesized at pH 7.0 or 10.0 than at pH 4.0. Moreover, we found that more arsenate was desorbed by phosphate from a

  1. Structural, magnetic and phonon properties of Cr(III)-doped perovskite metal formate framework [(CH3)2NH2][Mn(HCOO)3

    NASA Astrophysics Data System (ADS)

    Mączka, Mirosław; Gągor, Anna; Hermanowicz, Krzysztof; Sieradzki, Adam; Macalik, Lucyna; Pikul, Adam

    2016-05-01

    We have incorporated Cr(III) into [(CH3)2NH2][Mn(HCOO)3] (DMMn) multiferroic metal organic framework (MOF). The highest concentration of Cr(III) in the synthesized samples reached 15.9 mol%. The obtained samples were characterized by powder and single-crystal X-ray diffraction, DSC, magnetic susceptibility, dielectric, EPR, Raman and IR methods. These methods and the performed chemical analysis revealed that electrical charge neutrality after substitution of Cr(III) for Mn(II) is maintained by partial replacement of dimethylammonium (DMA+) cations by neutral HCOOH molecules. These changes in the chemical composition are responsible for weakening of the hydrogen bonds and decreased flexibility of the framework. This in turn leads to lowering of the ferroelectric phase transition temperature, observed around 185 K for undoped DMMn and around 155 K for the sample containing 3.1 mol% of Cr(III), and lack of macroscopic phase transition for the samples with Cr(III) content of 8.2 and 15.9 mol %. Another interesting effect observed for the studied samples is pronounced strengthening of the weak ferromagnetism of in Cr(III)-doped samples, associated with slight decrease of the ferromagnetic ordering temperature from 8.5 K for DMMn to 7.0 K for the sample with 15.9 mol % Cr(III) content.

  2. Dynamic chiral-at-metal stability of tetrakis(d/l-hfc)Ln(III) complexes capped with an alkali metal cation in solution.

    PubMed

    Lin, Yiji; Zou, Fang; Wan, Shigang; Ouyang, Jie; Lin, Lirong; Zhang, Hui

    2012-06-14

    Chiral tetrakis(β-diketonate) Ln(III) complexes Δ-[NaLa(d-hfc)(4)(CH(3)CN)] (1) and Λ-[NaLa(l-hfc)(4) (CH(3)CN)] (2) (d/l-hfc(-) = 3-heptafluo-robutylryl-(+)/(-)-camphorate) are a pair of enantiomers and crystallize in the same Sohncke space group (P2(1)2(1)2(1)) with dodecahedral (DD) geometry. Typically positive and negative exciton splitting patterns around 320 nm were observed in the solid-state circular dichroism (CD) spectra of complexes 1 and 2, which indicate that their shell configurational chiralities are Δ and Λ, respectively. The apparent bisignate couplets in the solid-state CD spectra of [CsLn(d-hfc)(4)(H(2)O)] [Ln = La (3), Yb (5)] and [CsLn(l-hfc)(4)(H(2)O)] [Ln = La (4), Yb (6)] show that they are a pair of enantiomers and their absolute configurations are denoted Δ and Λ, respectively. The crystallographic data of 5 reveals that its coordination polyhedron is the square antiprism (SAP) geometry and it undergoes a phase transition from triclinic (α phase, P1) to monoclinic (β phase, C2) upon cooling. The difference between the two phases is brought about by the temperature dependent behaviour of the coordination water molecules, but this did not affect the configurational chirality of the Δ-SAP-[Yb(d-hfc)(4)](-) moiety. Furthermore, time-dependent CD, UV-vis and (19)F NMR were applied to study the solution behavior of these complexes. It was found that the chiral-at-metal stability of the three pairs of complexes is different and affected by both the Ln(3+) and M(+) ion size. The results show that the Cs(+) cation can retain the metal center chirality and stablize the structures of [Ln(d/l-hfc)(4)](-) or the dissociated tris(d/l-hfc)Ln(III) species in solution for a longer time than that of the Na(+) cation, and it is important that the Cs(+) ion successfully lock the configurational chirality around the Yb(3+) center of the complex species in solution. This is reasoned by the short Cs(+)···FC, Cs(+)···O-Yb and Cs(+)···Yb(3

  3. Helical Striation Pattern Generation and Axial Field Compression in Aluminum Liner Experiments at 1 MA

    NASA Astrophysics Data System (ADS)

    Atoyan, Levon; Byvank, Tom; Greenly, John; Kusse, Bruce; Pikuz, Sergei; Potter, William; Shelkovenko, Tania; Hammer, David

    2015-11-01

    Awe et al. [Phys. Plasmas 21, 235005, 2014] found on the 20 MA Z machine that applying an externally generated axial magnetic field to an imploding liner produces a helical plasma pattern near the surface of the liner. Here we show that this phenomenon is also observed using 10 mm long cylindrical metal liners having 16 mm diameter and 3 to 6 μm wall thickness on the 1 MA, 100-200 ns COBRA pulsed power generator [T. A. Shelkovenko et al., Rev. Sci. Instrum. 77, 10F521, 2006]. The magnetic field in these experiments is created using a 150 μs rise time Helmholtz coil, and the pattern is observed using extreme ultraviolet imaging. Moreover, using B-dot probes we show that there is a 4-8% axial magnetic field compression relative to the initially applied Bz. Using a visible light framing camera, we show that this compression begins before the outside surface of the liner has become a visible light emitting plasma. This research was sponsored by the NNSA SSAP under DOE Coop Agreement DE-NA0001836 and DOE grant DE-NA0001847 as well as by NSF grant PHY-1102471.

  4. Friction Stir Welding of GR-Cop 84 for Combustion Chamber Liners

    NASA Technical Reports Server (NTRS)

    Russell, Carolyn K.; Carter, Robert; Ellis, David L.; Goudy, Richard

    2004-01-01

    GRCop-84 is a copper-chromium-niobium alloy developed by the Glenn Research Center for liquid rocket engine combustion chamber liners. GRCop-84 exhibits superior properties over conventional copper-base alloys in a liquid hydrogen-oxygen operating environment. The Next Generation Launch Technology program has funded a program to demonstrate scale-up production capabilities of GR-Cop 84 to levels suitable for main combustion chamber production for the prototype rocket engine. This paper describes a novel method of manufacturing the main combustion chamber liner. The process consists of several steps: extrude the GR-Cop 84 powder into billets, roll the billets into plates, bump form the plates into cylinder halves and friction stir weld the halves into a cylinder. The cylinder is then metal spun formed to near net liner dimensions followed by finish machining to the final configuration. This paper describes the friction stir weld process development including tooling and non-destructive inspection techniques, culminating in the successful production of a liner preform completed through spin forming.

  5. A modeling approach for the purification of group III metals (Ga and In) by zone refining

    SciTech Connect

    Ghosh, K.; Dhar, S.; Mani, V. N.

    2008-07-15

    An 'experimental friendly' model for zone refining process is proposed which predicts effective zone length in each refining passes that would lead to maximal solute removal, thereby leading to ultrapurification of the material for use in high-end electronic applications. The effectiveness of the model is experimentally tested and validated by purifying gallium from 4N (99.99%) to 6N5 (99.99995%) purity level at 30% yield and {approx}6 N at 70% yield with respect to targeted metallic impurities such as, Zn, Cu, Al, Ca, Bi, Si, Pb, Ni, Mn, and Fe, as analyzed by inductively coupled plasma optical emission spectrometry, graphite furnace atomic absorption spectrometry, and high resolution inductively coupled plasma mass spectrometry techniques. The distribution coefficient (k) of all the targeted impurities, detected in the purified gallium, was found to be less than 1. By comparing the experimentally obtained axial concentration profiles with the theoretical calculations, the k values of some detected impurities, such as Ca and Al, are determined to be {approx}0.8, Pb and Bi to be 0.7, Cu to be 0.65, and Fe to be 0.68, which prove the efficiency of the proposed model in reducing the concentration of these vulnerable impurities significantly. Following the model and as evidenced from the theoretical predictions, degradation of material purification containing a mixture of impurities having k less than as well as greater than 1 was elucidated experimentally by zone refining of 4N6 indium. Only a 40% yield of 5N6 indium was obtained, thereby highlighting the intricacies and problem areas in ultrapurification of these types of material.

  6. Kiloparsec-scale radio emission in Seyfert and LINER galaxies

    NASA Astrophysics Data System (ADS)

    Singh, Veeresh; Ishwara-Chandra, C. H.; Wadadekar, Yogesh; Beelen, Alexandre; Kharb, Preeti

    2015-01-01

    Seyfert and LINER galaxies are known to exhibit compact radio emission on ˜10-100 pc scales, but larger Kiloparsec-Scale Radio structures (KSRs) often remain undetected in sub-arcsec high-resolution observations. We investigate the prevalence and nature of KSRs in Seyfert and LINER galaxies using the 1.4 GHz VLA FIRST and NVSS observations. Our sample consists of 2651 sources detected in FIRST and of these 1737 sources also have NVSS counterparts. Considering the ratio of total to peak flux density (θ = (Sint/Speak)1/2) as a parameter to infer the presence of extended radio emission we show that ≥30 per cent of FIRST-detected sources possess extended radio structures on scales larger than 1.0 kpc. The use of low-resolution NVSS observations help us to recover faint extended KSRs that are resolved out in FIRST observations and results in ≥42.5 per cent KSR sources in FIRST-NVSS sub-sample. This fraction is only a lower limit owing to the combination of projection, resolution and sensitivity effects. Our study demonstrates that KSRs may be more common than previously thought and are found across all redshifts, luminosities and radio loudness. The extranuclear radio luminosity of KSR sources is found to be positively correlated with the core radio luminosity as well as the [O III] λ5007 Å line luminosity and this can be interpreted as KSRs being powered by AGN rather than star formation. The distributions of the FIR-to-radio ratios and mid-IR colours of KSR sources are also consistent with their AGN origin. However, contribution from star formation cannot be ruled out particularly in sources with low radio luminosities.

  7. Measurement of the solar neutrino capture rate with gallium metal, part III

    SciTech Connect

    Elliott, Steven Ray

    2008-01-01

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. In this article we present the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keY of 65.4{sup +3.1}{sub 3.0} (stat) {sup +2.6}{sub -2.8} (syst) SNU. The weighted average of the results of all three Ga solar neUlrino experiments, SAGE, Gallex, and GNO, is now 66.1 {+-} 3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced {sup 37}Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior {sup 51}Cr neutrino-source experiments with Ga, is 0.88 {+-} 0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in {sup 71}Ge has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63--67 SNU with an uncertainly of about 5%, in good agreement with experiment. We derive the current value of the pp neutrino flux produced in the Sun to be {phi}{sup {circle_dot}}{sub pp} = (6.1 {+-} 0.8) x 10{sup 10}/(cm{sup 2} s), which agrees well with the flux predicted by the standard solar model. Finally, we make several tests and show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

  8. Broadband Liner Optimization for the Source Diagnostic Test Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.

    2012-01-01

    The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more appealing. This paper describes a broadband acoustic liner optimization study for the scale model Source Diagnostic Test fan. Specifically, in-duct attenuation predictions with a statistical fan source model are used to obtain optimum impedance spectra over a number of flow conditions for three liner locations in the bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Typical tonal liner designs targeting single frequencies at one operating condition are first produced to provide baseline performance information. These are followed by multiple broadband design approaches culminating in a broadband liner targeting the full range of frequencies and operating conditions. The broadband liner is found to satisfy the optimum impedance objectives much better than the tonal liner designs. In addition, the broadband liner is found to provide better attenuation than the tonal designs over the full range of frequencies and operating conditions considered. Thus, the current study successfully establishes a process for the initial design and evaluation of novel broadband liner concepts for complex engine configurations.

  9. Low-Convergence Magnetized Liner Inertial Fusion

    NASA Astrophysics Data System (ADS)

    Slutz, Stephen; Vesey, Roger; Sinars, Daniel; Sefkow, Adam

    2013-10-01

    Numerical simulations indicate that pulsed-power driven liner-implosions could produce substantial fusion yields if the deuterium-tritium (DT) fuel is first magnetized and preheated [S.A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. As with all inertial fusion, the implosions could be degraded by the Rayleigh-Taylor instability. Since highly convergent implosions are more susceptible to this instability, we have explored the necessary conditions to obtain significant fusion yield with low-convergence liner-implosions. Such low-convergence implosions can be obtained if the fuel is sufficiently preheated and magnetized. We present analytic and numerical studies of laser plasma heating, which indicate that low convergence implosions should be possible with sufficient laser energy. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contra.

  10. Highly selective and sensitive detection of metal ions and nitroaromatic compounds by an anionic europium(iii) coordination polymer.

    PubMed

    Feyisa Bogale, Raji; Ye, Junwei; Sun, Yuan; Sun, Tongxin; Zhang, Siqi; Rauf, Abdul; Hang, Cheng; Tian, Peng; Ning, Guiling

    2016-07-01

    A luminescent Eu(iii)-based coordination polymer, {[Eu(H2O)5(BTEC)][H(C5H6N2)]·3H2O} () has been synthesized under hydrothermal conditions using 1,2,4,5-benzenetetracarboxylic acid (H4BTEC) as a linker. Compound possesses an anionic zig-zag chain constructed from the BTEC ligands and [EuO4(H2O)5] nodes. The protonated 4-aminopyridine groups as guests are located between chains. exhibits the characteristic sharp emission bands of Eu(3+) at 578, 593, 615, 652 and 693 nm upon excitation at 290 nm. The strong emission of could be quenched effectively by trace amounts of Fe(3+) ions even in the presence of other metal ions including Al(3+), Ca(2+), Cd(2+), Co(2+), Cr(3+), Cu(2+), Fe(2+), K(+), Mg(2+), Mn(2+), Pd(2+) and Zn(2+). Similarly, also exhibits superior selectivity and sensitivity towards 4-nitrophenol (4-NP) compared with other competing interfering analytes, such as 2,4,6-trinitrophenol, 2,6-dinitrotolune, 4-nitrotoluene, nitrobenzene, 1,3-dinitrobenzene, o-xylene, nitromethane, nitropropane, phenol, 4-bromophenol and bromobenzene, through a fluorescence quenching mechanism. The possible fluorescence quenching mechanisms are discussed. Moreover, could be used as a visual fluorescent test paper for selectively detecting trace amounts of Fe(3+) and 4-NP. PMID:27327158

  11. Highly selective and sensitive detection of metal ions and nitroaromatic compounds by an anionic europium(iii) coordination polymer.

    PubMed

    Feyisa Bogale, Raji; Ye, Junwei; Sun, Yuan; Sun, Tongxin; Zhang, Siqi; Rauf, Abdul; Hang, Cheng; Tian, Peng; Ning, Guiling

    2016-07-01

    A luminescent Eu(iii)-based coordination polymer, {[Eu(H2O)5(BTEC)][H(C5H6N2)]·3H2O} () has been synthesized under hydrothermal conditions using 1,2,4,5-benzenetetracarboxylic acid (H4BTEC) as a linker. Compound possesses an anionic zig-zag chain constructed from the BTEC ligands and [EuO4(H2O)5] nodes. The protonated 4-aminopyridine groups as guests are located between chains. exhibits the characteristic sharp emission bands of Eu(3+) at 578, 593, 615, 652 and 693 nm upon excitation at 290 nm. The strong emission of could be quenched effectively by trace amounts of Fe(3+) ions even in the presence of other metal ions including Al(3+), Ca(2+), Cd(2+), Co(2+), Cr(3+), Cu(2+), Fe(2+), K(+), Mg(2+), Mn(2+), Pd(2+) and Zn(2+). Similarly, also exhibits superior selectivity and sensitivity towards 4-nitrophenol (4-NP) compared with other competing interfering analytes, such as 2,4,6-trinitrophenol, 2,6-dinitrotolune, 4-nitrotoluene, nitrobenzene, 1,3-dinitrobenzene, o-xylene, nitromethane, nitropropane, phenol, 4-bromophenol and bromobenzene, through a fluorescence quenching mechanism. The possible fluorescence quenching mechanisms are discussed. Moreover, could be used as a visual fluorescent test paper for selectively detecting trace amounts of Fe(3+) and 4-NP.

  12. Rapid purification of recombinant dengue and West Nile virus envelope Domain III proteins by metal affinity membrane chromatography.

    PubMed

    Tan, Lik Chern Melvin; Chua, Anthony Jin Shun; Goh, Li Shan Liza; Pua, Shu Min; Cheong, Yuen Kuen; Ng, Mah Lee

    2010-11-01

    Arthropod-borne flaviviruses such as dengue virus (DENV) and West Nile virus (WNV) pose significant health threats to the global community. Due to escalating numbers of DENV and WNV infections worldwide, development of an effective vaccine remains a global health priority. As flavivirus envelope Domain III (DIII) protein is highly immunogenic and capable of inducing neutralizing antibodies against wild-type virus, it is both a potential protein subunit vaccine candidate and a suitable diagnostic reagent. Here, we describe the use of metal affinity membrane chromatography as a rapid and improved alternative for the purification of recombinant DIII (rDIII) antigens from DENV serotypes 1-4 and WNV - New York, Sarafend, Wengler and Kunjin strains. Optimum conditions for the expression, solubilization, renaturation and purification of these proteins were established. The purified proteins were confirmed by MALDI-TOF mass spectrometry and ELISA using antibodies raised against the respective viruses. Biological function of the purified rDIII proteins was confirmed by their ability to generate DIII-specific antibodies in mice that could neutralize the virus.

  13. Acoustic-Liner Admittance in a Duct

    NASA Technical Reports Server (NTRS)

    Watson, W. R.

    1986-01-01

    Method calculates admittance from easily obtainable values. New method for calculating acoustic-liner admittance in rectangular duct with grazing flow based on finite-element discretization of acoustic field and reposing of unknown admittance value as linear eigenvalue problem on admittance value. Problem solved by Gaussian elimination. Unlike existing methods, present method extendable to mean flows with two-dimensional boundary layers as well. In presence of shear, results of method compared well with results of Runge-Kutta integration technique.

  14. Ligational behavior of clioquinol antifungal drug towards Ag(I), Hg(II), Cr(III) and Fe(III) metal ions: Synthesis, spectroscopic, thermal, morphological and antimicrobial studies

    NASA Astrophysics Data System (ADS)

    El-Megharbel, Samy M.; Refat, Moamen S.

    2015-04-01

    This article presents a synthesis, characterization, theoretical and biological (anti-bacterial, and anti-fugal) evaluation studies of Ag(I), Hg(II), Cr(III) and Fe(III) complexes of clioquinol (CQ) drug ligand. Structures of the titled complexes cited herein were discussed using elemental analyses and spectral measurements e.g., IR, 1H NMR, and electronic studies. The results confirmed the formation of the clioquinol complexes by three molar ratios (1:1) for Ag(I), (1:2) for Hg(II) and (1:3) for both Cr(III) and Fe(III) metal ions. The clioquinol reacts as a bidentate chelate bound to all respected metal ions through the oxygen and nitrogen of quinoline-8-ol. The metal(II) ions coordinated to clioquinol ligand through deprotonation of sbnd OH terminal group. Infrared and 1H NMR spectral data confirm that coordination is via the oxygen of phenolic group and nitrogen atom of quinoline moiety. The molar conductance measurements of the CQ complexes in DMSO correspond to be non-electrolyte nature. Thus, these complexes may be formulated as [Ag(CQ)(H2O)2] H2O, [Hg(CQ)2]ṡ2H2O, [Cr(CQ)3] and [Fe(CQ)3]H2O. The Coats-Redfern method, the kinetic thermodynamic parameters like activation energies (E∗), entropies (ΔS∗), enthalpies (ΔH∗), and Gibbs free energies (ΔG∗) of the thermal decomposition reactions have been deduced from thermogravimetric curves (TG) with helpful of differential thermo gravimetric (DTG) curves. The narrow size distribution in nano-scale range for the clioquinol complexes have been discussed using X-ray powder diffraction (XRD), scanning electron microscope (SEM), and X-ray energy dispersive spectrometer (EDX) analyzer.

  15. ALFALFA Discovery of the nearby Gas-rich Dwarf Galaxy Leo P. III. An Extremely Metal Deficient Galaxy

    NASA Astrophysics Data System (ADS)

    Skillman, Evan D.; Salzer, John J.; Berg, Danielle A.; Pogge, Richard W.; Haurberg, Nathalie C.; Cannon, John M.; Aver, Erik; Olive, Keith A.; Giovanelli, Riccardo; Haynes, Martha P.; Adams, Elizabeth A. K.; McQuinn, Kristen B. W.; Rhode, Katherine L.

    2013-07-01

    We present KPNO 4 m and LBT/MODS spectroscopic observations of an H II region in the nearby dwarf irregular galaxy Leo P discovered recently in the Arecibo ALFALFA survey. In both observations, we are able to accurately measure the temperature sensitive [O III] λ4363 line and determine a "direct" oxygen abundance of 12 + log(O/H) = 7.17 ± 0.04. Thus, Leo P is an extremely metal deficient (XMD) galaxy, and, indeed, one of the most metal deficient star-forming galaxies ever observed. For its estimated luminosity, Leo P is consistent with the relationship between luminosity and oxygen abundance seen in nearby dwarf galaxies. Leo P shows normal α element abundance ratios (Ne/O, S/O, and Ar/O) when compared to other XMD galaxies, but elevated N/O, consistent with the "delayed release" hypothesis for N/O abundances. We derive a helium mass fraction of 0.2509^{+0.0184}_{-0.0123}, which compares well with the WMAP + BBN prediction of 0.2483 ± 0.0002 for the primordial helium abundance. We suggest that surveys of very low mass galaxies compete well with emission line galaxy surveys for finding XMD galaxies. It is possible that XMD galaxies may be divided into two classes: the relatively rare XMD emission line galaxies which are associated with starbursts triggered by infall of low-metallicity gas and the more common, relatively quiescent XMD galaxies like Leo P, with very low chemical abundances due to their intrinsically small masses. Some of the observations reported here were obtained at the LBT Observatory. The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The

  16. A novel method for study of the aggregation of protein induced by metal ion aluminum(III) using resonance Rayleigh scattering technique

    NASA Astrophysics Data System (ADS)

    Long, Xiufen; Zhang, Caihua; Cheng, Jiongjia; Bi, Shuping

    2008-01-01

    We present a novel method for the study of the aggregation of protein induced by metal ion aluminum(III) using resonance Rayleigh scattering (RRS) technique. In neutral Tris-HCl medium, the effect of this aggregation of protein results in the enhancement of RRS intensity and the relationship between the enhancement of the RRS signal and the Al concentration is nonlinear. On this basis, we established a new method for the determination of the critical induced-aggregation concentrations ( CCIAC) of metal ion Al(III) inducing the protein aggregation. Our results show that many factors, such as, pH value, anions, salts, temperature and solvents have obvious effects. We also studied the extent of aggregation and structural changes using ultra-violet spectrometry, protein intrinsic fluorescence and circular dichroism to further understand the exact mechanisms of the aggregation characteristics of proteins induced by metal ion Al(III) at the molecular level, to help us to develop effective methods to investigate the toxicity of metal ion Al, and to provide theoretical and quantitative evidences for the development of appropriate treatments for neurodementia such as Parkinson's disease, Alzheimer's disease and dementia related to dialysis.

  17. Thermodynamics of metal cation binding by a solid soil-derived humic acid: binding of Fe(III), Pb(II), and Cu(II).

    PubMed

    Ghabbour, Elham A; Shaker, Medhat; El-Toukhy, Ahmed; Abid, Ismail M; Davies, Geoffrey

    2006-04-01

    Metal binding and release by solid humic acids (HAs) in soils and sediments can affect metal mobility and bioavailability. Isotherms for tight binding of Fe(III), Pb(II) and Cu(II) by a solid humic acid at pH2.0 fit the Langmuir binding model. Low pH was chosen to protonate the HA carboxylate groups and avoid metal cation hydrolysis. Binding of Fe(III), Pb(II) and Cu(II) occurs in one detectable step labeled A. Site capacities nu(A) are temperature-independent from 10.0 to 40.0 degrees C and point to binding by charge-neutralization to form solid complexes M(OOC-R)(n)(s), where n appears to be 2 for Pb(II) and 3 for Fe(III). Thermodynamic data pairs (DeltaH(A), DeltaS(A)) for metal binding are linearly correlated with previous data for Ca(II), Co(II) and Mg(II) binding by solid HAs.

  18. Progress in plasma liner modeling for MIF

    NASA Astrophysics Data System (ADS)

    Loverich, John; Hakim, Ammar; Zhou, Sean

    2009-11-01

    Magnetic confinement fusion and inertial confinement fusion represent the two extremes in terms of density and confinement time in fusion energy research. Both approaches have been studied extensively through the decades pushing technology to the limits. An alternative fusion approach exists between these regimes called magnetized target fusion. In magnetized target fusion longer confinement times are achieved than in ICF through the use of strong magnetic fields, the long confinement time reduces the required plasma density to reach ignition--the approach has advantages over MFE in that it is much more compact and higher density. This work explores computationally a form of magnetized target implosion using a plasma liner. This concept is to be compared with solid liner implosion approach which may not be commercially viable as a reactor due to the ``standoff'' problem, portions of the device are destroyed with each target implosion. We present simulation results of plasma liner formation, jet merging, and plasma jet magnetized target interaction using a fluid plasma code (TxFluids) developed at Tech-X corporation.

  19. Overview of the Plasma Liner Experiment (PLX)

    NASA Astrophysics Data System (ADS)

    Hsu, S. C.; Witherspoon, F. D.; Cassibry, J. T.; Gilmore, M. A.; the PLX Team

    2011-10-01

    The Plasma Liner Experiment (PLX) is a multi-institutional collaboration that is exploring and demonstrating the formation of imploding spherical plasma liners to reach peak pressures exceeding 0.1 Mbar upon stagnation. The liners will be formed via the merging of 30 dense high Mach number plasma jets (n ~1017 cm-3, M ~ 10 -35, v ~ 50 km/s, rjet ~ 2 . 5 cm) in a spherically convergent geometry. We are aiming for two follow-on applications if this work is successful: (1) assembling repetitive, macroscopic (cm and μs scale) plasmas suitable for fundamental HEDLP scientific studies and (2) a standoff driver for magneto-inertial fusion. This is a staged project where scientific issues will be studied first at modest stored energies (~ 300 kJ) before attempting to reach HED- relevant pressures (requiring ~ 1 . 5 MJ). This poster provides an overview of the project's status/plans and emphasizes the progress made in the past year: completion of phase one facility and diagnostic construction, progress in numerical simulations, and initial experiments on single jet propagation and two jet merging. Finally, we describe cosmically-relevant collisionless shock experiments based on the head-on collision of two lower density but higher velocity plasma jets. Supported by DOE Fusion Energy Sciences and LANL LDRD.

  20. Effect of denture cleansers on surface hardness of resilient denture liners at various time intervals- an in vitro study

    PubMed Central

    Pahuja, Rasleen Kaur; Bansal, Sanjay

    2013-01-01

    PURPOSE This study was aimed to determine the effect of two chemically distinct denture cleansers and water on the surface hardness of acrylic and silicone based soft denture liners at various time intervals. MATERIALS AND METHODS Two commonly used commercial resilient liner material were selected based on their chemical composition (silicone- and acrylic-based soft liners) for this investigation. 120 cylindrical specimens were made of 15 mm × 10 mm dimensions (according to ASTM: D-2240-64T) in a custom made metal mold. All specimens were stored in artificial saliva throughout the study. Forty specimens were cleansed daily in 0.5% sodium hypochlorite solution; forty were cleansed in sodium perborate and remaining forty specimens were daily rinsed in water. Testing was done at 1 week, 1 month, 3 months and 6 months for surface hardness using a Shore A Durometer. A mean of 3 reading for each sample was subjected to one-way ANOVA, Post Hoc test and pair-t test for statistical analysis. P values of less than 0.05 were taken as statistically significant. RESULTS Surface hardness of all the samples was significantly higher after a period of 6 months irrespective of the cleansing treatment. Minor changes were observed between control, sodium hypochlorite and sodium perborate groups with time. Greater change was observed in surface hardness of acrylic-based soft denture liners as compared to silicone-based soft liners for all groups, as time progressed. CONCLUSION Silicone-based soft denture liners performed significantly better in all cleansing treatments than acrylic-based soft denture liners. PMID:24049568

  1. Unprecedented dinuclear Robson type macrocyclic complexes having two +iii metal ions in two compartments and the role of the diimino moiety on the stability of metal ion oxidation states.

    PubMed

    Mandal, Leena; Mohanta, Sasankasekhar

    2014-11-14

    The work in this investigation deals with the syntheses, characterization, crystal structures and catechol oxidase activity of four diphenoxo-bridged Co(III)Co(III) compounds of composition [Co(III)Co(III)L(Me-pn)(N3)4]·6H2O (), [Co(III)Co(III)L(Me-pn)(N3)4]·4H2O (), [Co(III)Co(III)L(Et-pn)(N3)4]·3.5H2O () and [Co(III)Co(III)L(Et-pn)(N3)4]·CH3CN·2.5H2O (), and two diphenoxo-bridged Co(III)Co(II) compounds of composition [Co(III)Co(II)L(Me-Me2pn)(N3)3]·2H2O () and [Co(III)Co(II)L(Et-Me2pn)(N3)3]·H2O (). In these compounds, H2L(Me-pn), H2L(Et-pn), H2L(Me-Me2pn) and H2L(Et-Me2pn) are four Robson type tetraiminodiphenolate macrocyclic ligands, in which the superscript Me and Et indicate that the dialdehyde components are 4-methyl-2,6-diformyl-phenol and 4-ethyl-2,6-diformyl-phenol, respectively, while pn and Me2pn indicate that the diamine components are 1,3-diaminopropane and 2,2-dimethyl-1,3-diaminopropane, respectively. The Co(III)Co(III) compounds are further characterized by (1)H NMR spectra. Compounds and are prepared following a metal-templated synthesis, while compounds and are prepared by direct synthesis, which includes using a pre-isolated macrocycle, [H4L(Me-pn)](ClO4)2/[H4L(Et-pn)](ClO4)2, as a reactant. On changing the diamine component of the corresponding macrocycle from 1,3-diaminopropane to 2,2-dimethyl-1,3-diaminopropane, but otherwise following the similar reaction procedure (both direct and template), the Co(III)Co(II) compounds [Co(III)Co(II)L(Me-Me2pn)(N3)3]·2H2O (), [Co(III)Co(II)L(Et-Me2pn)(N3)3]·H2O (), [Co(III)Co(II)L(Me-Me2pn)(N3)3]·0.5MeCN·0.27H2O (; Inorg. Chim. Acta, 2014, 412, 38) and [Co(III)Co(II)L(Et-Me2pn)(N3)3]·MeCN (; Dalton Trans., 2013, 42, 4561) are formed, rather than Co(III)Co(III) compounds. Like compounds and , all the compounds show catechol oxidase activity (substrate: 3,5-di-tert-butyl catechol). The kinetic parameters for , and have been determined. Their Kcat values are, respectively, 212.6, 188.0 and 191

  2. Method for selectively controlling flow across slotted liners

    SciTech Connect

    Peavy, M.A.; Dees, J.M.

    1993-08-31

    A process is described for decreasing flow rate across the radial boundary of a selected interval in a well bore containing a slotted liner comprising: placing an explosive and an internally catalyzed resin solution inside an elongated container; locating the elongated container opposite the selected interval in the well bore where flow rate through the slotted liner is to be decreased; firing the explosive; and allowing the resin to cure on the slotted liner before initiating flow through the well. A method is described for decreasing production of unwanted fluids from a horizontal well containing a slotted liner comprising: placing an explosive and an internally catalyzed resin inside an elongated container; placing the elongated container opposite an interval in the horizontal well where unwanted fluid is entering the well bore through the slotted liner; firing the explosive; and permitting the resin to cure on the slotted liner before initiating flow in the well.

  3. Accelerated aging tests of liners for uranium mill tailings disposal

    SciTech Connect

    Barnes, S.M.; Buelt, J.L.; Hale, V.Q.

    1981-11-01

    This document describes the results of accelerated aging tests to determine the long-term effectiveness of selected impoundment liner materials in a uranium mill tailings environment. The study was sponsored by the US Department of Energy under the Uranium Mill Tailings Remedial Action Project. The study was designed to evaluate the need for, and the performance of, several candidate liners for isolating mill tailings leachate in conformance with proposed Environmental Protection Agency and Nuclear Regulatory Commission requirements. The liners were subjected to conditions known to accelerate the degradation mechanisms of the various liners. Also, a test environment was maintained that modeled the expected conditions at a mill tailings impoundment, including ground subsidence and the weight loading of tailings on the liners. A comparison of installation costs was also performed for the candidate liners. The laboratory testing and cost information prompted the selection of a catalytic airblown asphalt membrane and a sodium bentonite-amended soil for fiscal year 1981 field testing.

  4. Correlating shaped charge performance with processing conditions and microstructure of an aluminum alloy 1100 liner enabled by a new method to arrest nascent jet formation

    NASA Astrophysics Data System (ADS)

    Scheid, James Eric

    Aluminum-lined shaped charges are used in special applications where jet and / or slug residue in the target is undesired. The three different microstructures of the aluminum liners studied herein resulted from three different manufacturing interpretations of the same design. One interpretation was completely machining the liners from best available annealed round stock. The second was to cold-forge the liners from annealed round-stock in an open-die forge to near-final dimensions, and then machine the liners to the final dimensions. The third variant in this study was to use the above forged liner, but with annealing after the machining. These three manufacturing choices resulted in significant variations in shaped charge performance. The goal of this research was to clarify the relationships between the liner metal microstructure and properties, and the corresponding shaped charge dynamic flow behavior. What began as an investigation into user-reported performance problems associated inherently with liner manufacturing processes and resultant microstructure, resolved into new understandings of the relationships between aluminum liner microstructure and shaped charge collapse kinetics. This understanding was achieved through an extensive literature review and the comprehensive characterization of the material properties of three variants of an 1100 aluminum shaped charge liner with a focus on collapse and nascent jet formation. The machined liner had a microstructure with large millimeter-sized grains and fine particles aligned in bands parallel to the charge axis. The forged liner microstructure consisted of very small one micrometer-sized (1 mum) subgrains and fine particles aligned largely in bands elongated parallel to the liner contour. The annealed liner was characterized by ten micrometer (10 mum) sized equiaxed grains with residual fine particles in the forged alignment. This characterization was enabled by the development, execution and validation of a

  5. Analysis of dry cylinder liner behavior during engine operation

    SciTech Connect

    Mizutani, Kazunori; Murata, Katsuhiro; Suzawa, Takashi; Niitsu, Yasuhiko

    1996-09-01

    Engine manufacturers are continuing to develop new engine designs that provide higher power output, lower fuel consumption and lower engine weight. In order to achieve significant engine weight reduction, the light weight cylinder block structure employs dry cylinder liners rather than wet cylinder liners. The cast iron dry liner structure is utilized because of the superior wear and scuff resistance of the cast iron. Thin wall dry cast iron liners are being employed in both gasoline and diesel engines. Dry cylinder liners with wall thickness of 1.5 mm are in production for Japanese automotive diesel engines. In the case of the dry thin wall cast iron liners, 2 design configurations are employed: loose-fit type having a specified clearance between the outer liner surface and the cylinder bore surface; press-in type having an interference fit between the outer surface of liner and the cylinder bore surface. The physical properties of cast iron must be considered during the design phase if successful production designs are to be provided. In addition the operating stress caused by piston slap, combustion pressure variation and resultant effect on operating stress in the liner must be considered during the design. This paper summarizes the results of a series of studies undertaken to determine the effect of piston slap, combustion pressure and initial stress on resultant behavior of thin wall cylinder liners under engine operating conditions. The resultant data may be utilized to improve the overall design of thin wall dry cylinder liners, especially for loose-fit liners.

  6. Electroanalytical and isothermal calorimetric study of As(III) complexation by the metal poisoning remediators, 2,3-dimercapto-1-propanesulfonate and meso-2,3-dimercaptosuccinic acid.

    PubMed

    Cavanillas, Santiago; Chekmeneva, Elena; Ariño, Cristina; Díaz-Cruz, José Manuel; Esteban, Miquel

    2012-10-01

    A recently developed methodology, which combines voltammetry, ITC, ESI-MS and several chemometric tools, has been applied for the first time to the study of As(III) complexes. The ligands considered, DMSA and DMPS, are commonly used to treat heavy metal poisoning. The study yields a reliable and consistent picture of the binding of As(III) by the chelating therapy agents DMSA and DMPS providing an unambiguous description of the stoichiometries of the complexes (ML(2), with the occasional appearance of ML in the case of DMSA), both ligands have stability constants of the same order, with a logβ(2) of 9.2 and 9.8, respectively. These values confirm the potential efficiency of both ligands in the treatment of As(III) poisoning.

  7. Enhanced liners for attenuating utility by-product liquors

    SciTech Connect

    Martin, W.J.; Dennison, D. )

    1990-03-01

    The enhancement of soil liners for selected inorganic solution species by improving attenuation properties neutralizing reagents was investigated. One soil type (Cole silt loam) and two coal combustion liquors (boiling cleaning waste (acidic) and water treatment system brine (alkaline)) were used in laboratory studies. These studies tested the effectiveness of the use of neutralizing reagents both as a direct solution treatment and as a neutralizing barrier in a waste impoundment. The two kinds of laboratory experiments conducted were batch experiments for assessing the reagent's effectiveness and for selecting some for further study, and column experiments to (1) investigate different reagent application techniques, (2) determine the reagent's effects on permeability, and (3) study the changes in contaminant mobility. The batch studies resulted in the selection of two cost-effective neutralizing agents, hydrated lime (Ca(OH){sub 2}) for the acidic waste and alum (Al{sub 2}(SO{sub 4}){sub 3}{center dot}8H{sub 2}O) for the alkaline waste. In the column studies, these reagents were incorporated several ways in amending a soil liner to create neutralizing barriers. The results showed that a layered combination of homogeneous amended soil over unamended soil provided the most applicable and effective barrier with acceptable permeability. Precipitation, adsorption, and bacteriological activity were the major mechanisms involved in changing contaminant mobility and permeability. Several mineralogical changes occurred during contact in both studies, although the most significant was the precipitation of iron hydroxide and aluminum hydroxide, with their subsequent adsorption of trace metals. 13 refs., 26 figs.

  8. Durability of organobentonite-amended liner for decelerating chloroform transport.

    PubMed

    He, Shichong; Zhu, Lizhong

    2016-04-01

    Chloroform is added to landfill for suppressing methane generation, which however may transport through landfill liners and lead to contamination of groundwater. To decelerate chloroform transport, the enhanced sorption ability of clay liners following organobentonite addition was tested. In this study, we used batch sorption to evaluate sorption capacity of chloroform to organobentonite, followed by column tests and model simulations for assessing durability of different liners. Results show that adding 10% CTMAB-bentonite (organobentonite synthesized using cetyltrimethylammonium bromide) increased the duration of a bentonite liner by 88.5%. CTMAB-bentonite consistently showed the highest sorption capacity (Qm) among six typical organobentonites under various environmental conditions. The removal rate of chloroform by CTMAB-bentonite was 3.6-23 times higher than that by natural soils. According to the results derived by model simulation, a 70-cm 10% CTMAB-bentonite liner exhibited much better durability than a 100-cm compact clay liner (CCL) and natural bentonite liner evidenced by the delayed and lower peak of eluent concentration. A minimum thickness of 65.8 cm of the 10% CTMAB-bentonite liner could completely sorb the chloroform in a 100-m-high landfill. The 10% CTMAB-bentonite liner exhibiting much better durability has the promise for reducing environmental risk of chloroform in landfill.

  9. Optimization and Control of Acoustic Liner Impedance with Bias Flow

    NASA Technical Reports Server (NTRS)

    Wood, Houston; Follet, Jesse

    2000-01-01

    Because communities are impacted by steady increases in aircraft traffic, aircraft noise continues to be a growing problem for the growth of commercial aviation. Research has focused on improving the design of specific high noise source areas of aircraft and on noise control measures to alleviate noise radiated from aircraft to the surrounding environment. Engine duct liners have long been a principal means of attenuating engine noise. The ability to control in-situ the acoustic impedance of a liner would provide a valuable tool to improve the performance of liners. The acoustic impedance of a liner is directly related to the sound absorption qualities of that liner. Increased attenuation rates, the ability to change liner acoustic impedance to match various operating conditions, or the ability to tune a liner to more precisely match design impedance represent some ways that in-situ impedance control could be useful. With this in mind, the research to be investigated will focus on improvements in the ability to control liner impedance using a mean flow through the liner which is referred to as bias flow.

  10. Theory and Modeling of the Plasma Liner Experiment (PLX)

    NASA Astrophysics Data System (ADS)

    Cassibry, J. T.; Stanic, M. D.; Awe, T. J.; Hanna, D. S.; Davis, J. S.; Hsu, S. C.; Witherspoon, F. D.

    2010-11-01

    High pressures and temperatures may be generated at the center an imploding plasma liner. These phenomena are being studied on the Plasma Liner Experiment (PLX) in which a spherical liner is formed via the merging of plasma jets. The basic physical processes include pulsed plasma acceleration, plasma jet propagation in a vacuum, plasma jet merging, liner formation, liner implosion, stagnation, and rarefaction. Each of these processes is dominated by different physics, requiring different models. For example, λei at the jet merging radius may be ˜1 cm, so that liner formation is partially collisionless, while liner implosion is collision dominated. Further, the liner transitions from optically thin to gray during the implosion. An overview of the theory and modeling plan in support of PLX will be given, which includes 1D rad-hydro, 3D hydro, 3D MHD, 2D PIC, and 2D hybrid codes. We will emphasize our recent 3D hydro modeling, which provides insights into liner formation, implosion, and effects of initial jet parameters on scaling of peak pressure.

  11. Novel transition metal complexes of 4-hydroxy-coumarin-3-thiocarbohydrazone: Pharmacodynamic of Co(III) on rats and antimicrobial activity

    NASA Astrophysics Data System (ADS)

    Mosa, A. I.; Emara, Adel A. A.; Yousef, J. M.; Saddiq, A. A.

    2011-10-01

    A new series of stable transition metal complexes of the formula M(L)X·S, where M = Cu(II), Ni(II), Co(III), Cr(III) and Fe(III) and L is the deprotonated ligand of 4-hydroxy-coumarin-3-thiocarbohydrazone, X = Cl -, NO 3- or CH 3COO - and S = H 2O and/or EtOH. The HL ligand was prepared by the reaction of 3-formyl-4-hydroxy-coumarine with thiocarbohydrazide in the molar ratio 1:1. The HL ligand and its metal complexes were characterized by elemental analysis, 1H NMR, IR and electronic spectra, and molar conductance and magnetic measurements and thermal gravimetric analysis (TGA). The HL ligand acts as a monobasic tridentate ONS donor in all metal complexes, and coordinated through the phenolic OH, azomethine nitrogen and thione sulfur. Electronic spectra with magnetic moments suggested varieties of geometries around the central metal atoms. Thermal gravimetric analysis indicates that the complexes are stable up to 300 °C, and release the uncoordinated and/or coordinated H 2O/solvent molecules, which is accompanied by a color change. The formed complexes after releasing the solvent were investigated and their structures are suggested to have square planar or octahedral arrangement. Pharmacodynamic of cobalt(III) complex on some biochemical parameters and histological studies in serum and heart tissue in rats have been studied. Although the complexes demonstrated a significant effect at low dose than the high dose, the ligand showed significant good effects in both high and low doses on the biochemical analysis in serum and heart tissue. Cobalt complex was screened in order to evaluate its antifungal activity against the filamentous fungi Aspergillus niger, Aspergillus fumigatus, and Aspergillus flavus, and antibacterial activity against the Candida albicans, Escherichia coli, Klebseilla pneumoniae and Pseudomonas aeruginosa.

  12. Novel transition metal complexes of 4-hydroxy-coumarin-3-thiocarbohydrazone: pharmacodynamic of Co(III) on rats and antimicrobial activity.

    PubMed

    Mosa, A I; Emara, Adel A A; Yousef, J M; Saddiq, A A

    2011-10-15

    A new series of stable transition metal complexes of the formula M(L)X·S, where M = Cu(II), Ni(II), Co(III), Cr(III) and Fe(III) and L is the deprotonated ligand of 4-hydroxy-coumarin-3-thiocarbohydrazone, X = Cl(-), NO(3)(-) or CH(3)COO(-) and S = H(2)O and/or EtOH. The HL ligand was prepared by the reaction of 3-formyl-4-hydroxy-coumarine with thiocarbohydrazide in the molar ratio 1:1. The HL ligand and its metal complexes were characterized by elemental analysis, (1)H NMR, IR and electronic spectra, and molar conductance and magnetic measurements and thermal gravimetric analysis (TGA). The HL ligand acts as a monobasic tridentate ONS donor in all metal complexes, and coordinated through the phenolic OH, azomethine nitrogen and thione sulfur. Electronic spectra with magnetic moments suggested varieties of geometries around the central metal atoms. Thermal gravimetric analysis indicates that the complexes are stable up to 300°C, and release the uncoordinated and/or coordinated H(2)O/solvent molecules, which is accompanied by a color change. The formed complexes after releasing the solvent were investigated and their structures are suggested to have square planar or octahedral arrangement. Pharmacodynamic of cobalt(III) complex on some biochemical parameters and histological studies in serum and heart tissue in rats have been studied. Although the complexes demonstrated a significant effect at low dose than the high dose, the ligand showed significant good effects in both high and low doses on the biochemical analysis in serum and heart tissue. Cobalt complex was screened in order to evaluate its antifungal activity against the filamentous fungi Aspergillus niger, Aspergillus fumigatus, and Aspergillus flavus, and antibacterial activity against the Candida albicans, Escherichia coli, Klebseilla pneumoniae and Pseudomonas aeruginosa. PMID:21723186

  13. Probing off-Hugoniot states in Ta, Cu, and Al to 1000 GPa compression with magnetically driven liner implosions

    NASA Astrophysics Data System (ADS)

    Lemke, R. W.; Dolan, D. H.; Dalton, D. G.; Brown, J. L.; Tomlinson, K.; Robertson, G. R.; Knudson, M. D.; Harding, E.; Mattsson, A. E.; Carpenter, J. H.; Drake, R. R.; Cochrane, K.; Blue, B. E.; Robinson, A. C.; Mattsson, T. R.

    2016-01-01

    We report on a new technique for obtaining off-Hugoniot pressure vs. density data for solid metals compressed to extreme pressure by a magnetically driven liner implosion on the Z-machine (Z) at Sandia National Laboratories. In our experiments, the liner comprises inner and outer metal tubes. The inner tube is composed of a sample material (e.g., Ta and Cu) whose compressed state is to be inferred. The outer tube is composed of Al and serves as the current carrying cathode. Another aluminum liner at much larger radius serves as the anode. A shaped current pulse quasi-isentropically compresses the sample as it implodes. The iterative method used to infer pressure vs. density requires two velocity measurements. Photonic Doppler velocimetry probes measure the implosion velocity of the free (inner) surface of the sample material and the explosion velocity of the anode free (outer) surface. These two velocities are used in conjunction with magnetohydrodynamic simulation and mathematical optimization to obtain the current driving the liner implosion, and to infer pressure and density in the sample through maximum compression. This new equation of state calibration technique is illustrated using a simulated experiment with a Cu sample. Monte Carlo uncertainty quantification of synthetic data establishes convergence criteria for experiments. Results are presented from experiments with Al/Ta, Al/Cu, and Al liners. Symmetric liner implosion with quasi-isentropic compression to peak pressure ˜1000 GPa is achieved in all cases. These experiments exhibit unexpectedly softer behavior above 200 GPa, which we conjecture is related to differences in the actual and modeled properties of aluminum.

  14. Probing off-Hugoniot states in Ta, Cu, and Al to 1000 GPa compression with magnetically driven liner implosions

    DOE PAGES

    Lemke, R. W.; Dolan, D. H.; Dalton, D. G.; Brown, J. L.; Tomlinson, K.; Robertson, G. R.; Knudson, M. D.; Harding, E.; Mattsson, A. E.; Carpenter, J. H.; et al

    2016-01-07

    We report on a new technique for obtaining off-Hugoniot pressure vs. density data for solid metals compressed to extreme pressure by a magnetically driven liner implosion on the Z-machine (Z) at Sandia National Laboratories. In our experiments, the liner comprises inner and outer metal tubes. The inner tube is composed of a sample material (e.g., Ta and Cu) whose compressed state is to be inferred. The outer tube is composed of Al and serves as the current carrying cathode. Another aluminum liner at much larger radius serves as the anode. A shaped current pulse quasi-isentropically compresses the sample as itmore » implodes. The iterative method used to infer pressure vs. density requires two velocity measurements. Photonic Doppler velocimetry probes measure the implosion velocity of the free (inner) surface of the sample material and the explosion velocity of the anode free (outer) surface. These two velocities are used in conjunction with magnetohydrodynamic simulation and mathematical optimization to obtain the current driving the liner implosion, and to infer pressure and density in the sample through maximum compression. This new equation of state calibration technique is illustrated using a simulated experiment with a Cu sample. Monte Carlo uncertainty quantification of synthetic data establishes convergence criteria for experiments. Results are presented from experiments with Al/Ta, Al/Cu, and Al liners. Symmetric liner implosion with quasi-isentropic compression to peak pressure ~1000 GPa is achieved in all cases. Lastly, these experiments exhibit unexpectedly softer behavior above 200 GPa, which we conjecture is related to differences in the actual and modeled properties of aluminum.« less

  15. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... shoe, or subsequent liner shoes if set. The District Manager may approve or require other liner test... formation fracture pressure at the casing shoe into which the liner is lapped. (c) You may not...

  16. Effect of ceramic coating of JT8D combustor liner on maximum liner temperatures and other combustor performance parameters

    NASA Technical Reports Server (NTRS)

    Butze, H. F.; Liebert, C. H.

    1976-01-01

    The effect of ceramic coating of a JT8D combustor liner was investigated at simulated cruise and takeoff conditions with two fuels of widely different aromatic contents. Substantial decreases in maximum liner temperatures and flame radiation values were obtained with the ceramic-coated liner. Small reductions in exhaust gas smoke concentrations were observed with the ceramic-coated liner. Other performance parameters such as combustion efficiency and emissions of unburned hydrocarbons, CO, and NOx were not affected significantly. No deterioration of the ceramic coating was observed after about 6 hours of cyclic operation including several startups and shutdowns.

  17. Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners.

    PubMed

    Arora, Rajesh; Kapur, Ravi; Sibal, Nikhil; Juneja, Sumit

    2012-09-01

    The advent of the esthetic era and advances in adhesive technology saw the emergence of resin composite materials. But the problem of polymerization shrinkage remained. This was due to the contraction of the resin during curing inducing internal and interfacial stresses at the tooth restoration interface, leading to gap formation and subsequent micro-leakage. A number of techniques and modifications in the material have been proposed to minimize polymerization shrinkage and microleakage. In this study, the hypothesis that the placement of resin-modified glass ionomer cement (RMGIC) or flowable composite, as liner, beneath the packable composite, on the gingival surface of the tooth [coronal or apical to cementoenamel junction (CEJ)], could reduce the microleakage in class II composite restorations, was tested. Sixty recently extracted noncarious human mandibular molars were used. The teeth were randomly divided into three groups (20 specimens each): Group I (Filtek P60 with RMGIC liner), group II (Filtek P60 with Filtek Z350 liner) and Group III (Filtek P60 without liner). The teeth of each group were further subdivided into two subgroups (equal number of cavities). Subgroup A gingival seat 1 mm occlusal to CEJ on mesial side. Subgroup B gingival seat 1 mm apical to CEJ on distal side. It was concluded that in class II composite restorations gingival microleakage is more at the dentinal surface than on enamel. The use of a flowable composite and RMGIC, as liners, beneath the packable composite, in class II composite restorations, significantly reduces the microleakage when margins are in dentin, but the reverse is true, when the margins are in enamel. How to cite this article: Arora R, Kapur R, Sibal N, Juneja S. Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners. Int J Clin Pediatr Dent 2012;5(3):178-184. PMID:25206164

  18. Neutron Diffraction Characterization of Residual Strain in Welded Inconel 718 for NASA Space Shuttle Flow Liners

    SciTech Connect

    Rathod, C.R.; Vaidyanathan, R.; Livescu, V.; Clausen, B.; Bourke, M. A. M.; Notardonato, W.U.; Femminineo, M.

    2004-06-28

    This work quantitatively assesses residual strains and stresses associated with the weld repair process used to repair cracks on NASA's space shuttle flow liners. The coupons used in this investigation were made of the same INCONEL 718 alloy used for the flow liners. They were subjected to identical welding and certification procedures that were carried out on the space shuttle. Neutron diffraction measurements at Los Alamos National Laboratory determined residual strains at selected locations in a welded coupon at 293 K and 135 K. The weld repair process introduced Mises effective residual stresses of up to 555 MPa. On comparing the measurements at 293 K and 135 K, no significant change to the residual strain profile was noted at the low temperature. This indicated minimal mismatch in the coefficients of thermal expansion between the base metal and the weld.

  19. Neutron Diffraction Characterization of Residual Strain in Welded Inconel 718 for NASA Space Shuttle Flow Liners

    NASA Astrophysics Data System (ADS)

    Rathod, C. R.; Livescu, V.; Clausen, B.; Bourke, M. A. M.; Notardonato, W. U.; Femminineo, M.; Vaidyanathan, R.

    2004-06-01

    This work quantitatively assesses residual strains and stresses associated with the weld repair process used to repair cracks on NASA's space shuttle flow liners. The coupons used in this investigation were made of the same INCONEL 718 alloy used for the flow liners. They were subjected to identical welding and certification procedures that were carried out on the space shuttle. Neutron diffraction measurements at Los Alamos National Laboratory determined residual strains at selected locations in a welded coupon at 293 K and 135 K. The weld repair process introduced Mises effective residual stresses of up to 555 MPa. On comparing the measurements at 293 K and 135 K, no significant change to the residual strain profile was noted at the low temperature. This indicated minimal mismatch in the coefficients of thermal expansion between the base metal and the weld.

  20. Full-Scale GRCop-84 Combustion Chamber Liner Preform Fabricated Successfully

    NASA Technical Reports Server (NTRS)

    Ellis, David L.; Russell, Carolyn K.; Goudy, Rick

    2005-01-01

    GRCop-84 (Cu-8 at.% Cr-4 at.% Nb) has been under development at the NASA Glenn Research Center for several years. The alloy possesses a unique combination of good thermal conductivity, high elevated temperature strength, long creep life, and long low-cycle- fatigue. The alloy is also more oxidation resistant than pure copper and most competitive alloys. The combination of properties has attracted attention from major rocket engine manufacturers who are interested in the alloy for the combustion chamber liner in their next generation of regeneratively cooled engines. Before GRCop-84 can be used in a main combustion chamber application, it must be demonstrated that the alloy can be made successfully to the large sizes and proper shape needed and that it retain useful properties. Recent efforts have successfully demonstrated the ability to fabricate a liner preform via metal spinning that retains the alloy s strength even in the welded sections.

  1. Evaluation of Skin Friction Drag for Liner Applications in Aircraft

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Brown, Martha C.; Jasinski, Christopher M.

    2016-01-01

    A parameter that is gaining significance in the evaluation of acoustic liner performance is the skin friction drag induced by air flow over the liner surface. Estimates vary widely regarding the amount of drag the liner induces relative to a smooth wall, from less than a 20% increase to nearly 100%, and parameters such as face sheet perforate hole diameter, percent open area, and sheet thickness are expected to figure prominently in the skin friction drag. Even a small increase in liner drag can impose an economic penalty, and current research is focused on developing 'low drag' liner concepts, with the goal being to approach the skin friction drag of a smooth wall. The issue of skin friction drag takes on greater significance as airframe designers investigate the feasibility of putting sound absorbing liners on the non-lifting surfaces of the wings and fuselage, for the purpose of reducing engine noise reflected and scattered toward observers on the ground. Researchers at the NASA Langley Research Center have embarked on investigations of liner skin friction drag with the aims of: developing a systematic drag measurement capability, establishing the drag of current liners, and developing liners that produce reduced drag without compromising acoustic performance. This paper discusses the experimental procedures that have been developed to calculate the drag coefficient based on the change in momentum thickness and the companion research program being carried out to measure the drag directly using a force balance. Liner samples that are evaluated include a solid wall with known roughness and conventional liners with perforated facesheets of varying hole diameter and percent open area.

  2. Verification of a variable rate sprayer for nursery liner applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An experimental variable-rate sprayer designed for liner applications was tested by comparing its spray deposit and coverage, and droplet density inside canopies of six nursery liner varieties with constant-rate applications. Spray samplers, including water sensitive papers (WSP) and nylon screens, ...

  3. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calcium hydroxide cavity liner. 872.3250 Section 872.3250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner....

  4. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Calcium hydroxide cavity liner. 872.3250 Section 872.3250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner....

  5. CONSTRUCTION, MONITORING, AND PERFORMANCE OF TWO SOIL LINERS

    EPA Science Inventory

    A prototype soil liner and a field-scale soil liner were constructed to test whether compacted soil barrier systems could be built to meet the standard set by the U.S. Environmental Protection Agency (EPA) for saturated hydraulic conductivity (< 1 x 10'7 cm/s). In situ ponded inf...

  6. ONERA-NASA Cooperative Effort on Liner Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Primus, Julien; Piot, Estelle; Simon, Frank; Jones, Michael G.; Watson, Willie R

    2013-01-01

    As part of a cooperation between ONERA and NASA, the liner impedance eduction methods developed by the two research centers are compared. The NASA technique relies on an objective function built on acoustic pressure measurements located on the wall opposite the test liner, and the propagation code solves the convected Helmholtz equation in uniform ow using a finite element method that implements a continuous Galerkin discretization. The ONERA method uses an objective function based either on wall acoustic pressure or on acoustic velocity acquired above the liner by Laser Doppler Anemometry, and the propagation code solves the linearized Euler equations by a discontinuous Galerkin discretization. Two acoustic liners are tested in both ONERA and NASA ow ducts and the measured data are treated with the corresponding impedance eduction method. The first liner is a wire mesh facesheet mounted onto a honeycomb core, designed to be linear with respect to incident sound pressure level and to grazing ow velocity. The second one is a conventional, nonlinear, perforate-over-honeycomb single layer liner. Configurations without and with ow are considered. For the nonlinear liner, the comparison of liner impedance educed by NASA and ONERA shows a sensitivity to the experimental conditions, namely to the nature of the source and to the sample width.

  7. Optimal Spray Application Rates for Ornamental Nursery Liner Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spray deposition and coverage at different application rates for nursery liners of different sizes were investigated to determine the optimal spray application rates. Experiments were conducted on two and three-year old red maple liners. A traditional hydraulic sprayer with vertical booms was used t...

  8. Wet/dry cylinder liner for high output engines

    SciTech Connect

    Eisenberg, E.; Lindsay, F.E.; Evans, J.J.; Collins, R.H.

    1990-05-22

    This patent describes a cooling arrangement in an internal combustion engine comprising a cylinder head and cylinders each of which includes a cylinder wall and cylinder bore. It comprises: a cylinder liner having a predetermined length and being received in each of the bores, a lower portion of each liner being a dry portion of the liner which is received in a corresponding bore with an interference fit along the substantial length of the lower portion under operating conditions, the lower portion constituting approximately two-third of the length of the liner and providing support for the liner; an upper portion of the liner being disposed at a combustion region of the cylinder and being formed to provide a plurality of passages for liquid coolant extending in a substantially parallel arcuate paths around the cylinder liner, the arcuate paths comprise means for increasing velocity of the liquid coolant around the combustion region the passages being of substantially constant cross-section so as to provide substantially uniform high velocity circulation of liquid coolant around the cylinder liner in the combustion region.

  9. IUE and Einstein observations of the LINER galaxy NGC 4579

    NASA Technical Reports Server (NTRS)

    Reichert, G. A.; Puchnarewicz, E. M.; Mason, K. O.

    1990-01-01

    Results of International Ultraviolet Explorer (IUE) and Einstein observations of the LINER galaxy NGC 4579 are reported. Spatial profiles of the long wavelength IUE emission show a two component structure, with an unresolved core superimposed on broader underlying emission. The core spectrum shows strong C II lambda 2326 and broad Mg II lambda 2800 emission, and perhaps emission due to blends of Fe II multiplets (2300 to 23600 angstrom). The short wavelength emission is spatially unresolved, and shows C II lambda 1335, C III lambda 1909 broad C IV lambda 1550 emission, and a broad feature at approximately 1360 angstrom which may be due to 0.1 lambda 1356. Contrary to previous reports no evidence for He II lambda 1640 is found in the spectrum. An unresolved x ray source is detected at the location of the nucleus; its spectrum is well fitted by a power law of energy slope alpha approximately -0.5. These results further support the idea that NGC 4579 may contain a dwarf Seyfert nucleus.

  10. Hydraulic conductivity of three geosynthetic clay liners

    SciTech Connect

    Estornell, P.; Daniel, D.E.

    1992-01-01

    The hydraulic conductivity of three 2.9 sq m (32 sq ft) geosynthetic clay liners (GCLs) was measured. Tests were performed on individual sheets of the GCLs, on overlapped pieces of GCLs, and on composite liners consisting of a punctured geomembrane overlying a GCL. Hydraulic conductives of two of the GCLs were in the range of 10 to the minus 10 10 to the minus 8 cm/s. No flow was measured through the third GCL, but the conductivity was obviously very low. The hydraulic conductivities of overlapped GCLs were about the same as those of the control samples with no overlap; an effective hydraulic seal developed along the overlaps in all the materials tested. Performance of the punctured geomembrane-GCL composites varied--performance was best when the punctured geomembrane was placed directly against bentonite and no geotextile separated the punctured geomembrane from the bentonite. For those GCLs with geotextiles on both sides, problems with migration of bentonite into the underlying drainage layer were encountered when inadequate filtration was provided. However, with a suitable filtration layer separating the drainage layer from the GCL, problems with migration of bentonite were liminated.

  11. Modular liquid-cooled helmet liner for thermal comfort

    NASA Technical Reports Server (NTRS)

    Williams, B. A.; Shitzer, A.

    1974-01-01

    A modular liquid-cooled helmet liner made of eight form-fitting neoprene patches was constructed. The liner was integrated into the sweatband of an Army SPH-4 helicopter aircrew helmet. This assembly was tested on four subjects seated in a hot (47 C), humid (40%) environment. Results indicate a marked reduction in the rate of increase of physiological body functions. Rectal temperature, weight loss, heart rate, and strain indices are all reduced to approximately 50% of uncooled levels. The cooling liner removed from 10% to 30% of total metabolic heat produced. This study also demonstrated the technical feasilibity of using a cooling liner in conjunction with a standard hard helmet. Potential applications of the cooling liner in thermally stressful environments are numerous, notably for helicopter and other aircrews.

  12. Evaluating the accuracy of wear formulae for acetabular cup liners.

    PubMed

    Wu, James Shih-Shyn; Hsu, Shu-Ling; Chen, Jian-Horng

    2010-02-01

    This study proposes two methods for exploring the wear volume of a worn liner. The first method is a numerical method, in which SolidWorks software is used to create models of the worn out regions of liners at various wear directions and depths. The second method is an experimental one, in which a machining center is used to mill polyoxymethylene to manufacture worn and unworn liner models, then the volumes of the models are measured. The results show that the SolidWorks software is a good tool for presenting the wear pattern and volume of a worn liner. The formula provided by Ilchmann is the most suitable for computing liner volume loss, but is not accurate enough. This study suggests that a more accurate wear formula is required. This is crucial for accurate evaluation of the performance of hip components implanted in patients, as well as for designing new hip components.

  13. Waterproof versus cotton cast liners: a randomized, prospective comparison.

    PubMed

    Haley, Chad A; DeJong, E Schuyler; Ward, John A; Kragh, John F

    2006-03-01

    Casting injured extremities can cause complications (eg, itching, odor, rashes, skin maceration), many of which are associated with the inability to wash the extremity because of water retention and slow drying of conventional cast liners. A waterproof cast liner allows casts to become wet and perhaps improves hygiene and comfort. Fifty-nine patients (age, > or = 10 years) with upper or lower extremity injuries were randomized to a waterproof-liner group (n = 29) or a cotton-liner group (n = 30). Both groups had casts made of fiberglass tape. At each clinic visit, patients and physicians completed questionnaires evaluating comfort and skin condition, respectively. The waterproof-liner group had better scores for itch (P = .008), discomfort (P < .001), irritation (P = .002), overall patient score (P = .012), and overall physician score (P = .049).

  14. High energy imploding liner experiment HEL-1: Experimental results

    SciTech Connect

    Clark, D.A.; Anderson, B.G.; Ekdahl, C.A.

    1997-09-01

    Magnetically driven imploding liner systems can be used as a source of shock energy for materials equation of state studies, implosion driven magnetized plasma fusion experiments, and other similar applications. The imploding liner is a cylinder of conducting material through which a current is passed in the longitudinal direction. Interaction of the current with its own magnetic field causes the liner to implode. Sources of electrical energy for imploding liner systems are capacitor banks or explosive pulse power systems seeded by capacitor banks. In August, 1996, a high energy liner experiment (HEL-1) was conducted at the All-Russia Scientific Research Institute (VNIIEF) in Sarov, Russia. A 5 tier 1 meter diameter explosive disk generator provided electrical energy to drive a 48 cm outside diameter, 4 mm thick, aluminum alloy liner having a mass of about 11kg onto an 11 cm diameter diagnostic package. The purpose of the experiment was to measure performance of the explosive pulse power generator and the heavy imploding liner. Electrical performance diagnostics included inductive (B-dot) probes, Faraday Rotation current measurement, Rogowski total current measurement, and voltage probes. Flux loss and conductor motion diagnostics included current-joint voltage measurements and motion sensing contact pins. Optical and electrical impact pins, inductive (B-dot) probes, manganin pressure probes, and continuously recording resistance probes in the Central Measuring Unit (CMU) and Piezo and manganin pressure probes, optical beam breakers, and inductive probes located in the glide planes were used as liner symmetry and velocity diagnostics. Preliminary analysis of the data indicate that a peak current of more than 100 MA was attained and the liner velocity was between 6.7 km/sec and 7.5 km/sec. Liner kinetic energy was between 22 MJ and 35 MJ. 4 refs., 6 figs., 1 tab.

  15. Laboratory measurements of contaminant attenuation of uranium mill tailings leachates by sediments and clay liners

    SciTech Connect

    Serne, R.J.; Peterson, S.R.; Gee, G.W.

    1983-04-01

    We discuss FY82 progress on the development of laboratory tools to aid in the prediction of migration potential of contaminants present in acidic uranium mill tailings leachate. Further, empirical data on trace metal and radionuclide migration through a clay liner are presented. Acidic uranium mill tailings solution from a Wyoming mill was percolated through a composite sediment called Morton Ranch Clay liner. These laboratory columns and subsequent sediment extraction data show: (1) As, Cr, Pb, Ag, Th and V migrate very slowly; (2) U, Cd, Ni, Zn, Fe, Mn and similar transition metals are initially immobilized during acid neutralization but later are remobilized as the tailings solution exhausts the clay liner's acid buffering capacity. Such metals remain immobilized as long as the effluent pH remains above a pH value of 4 to 4.5, but they become mobile once the effluent pH drops below this range; and (3) fractions of the Se and Mo present in the influent tailings solution are very mobile. Possible controlling mechanisms for the pH-dependent immobilization-mobilization of the trace metals are discussed. More study is required to understand the controlling mechanisms for Se and Mo and Ra for which data were not successfully collected. Using several column lengths (from 4.5 to 65 cm) and pore volume residence times (from 0.8 to 40 days) we found no significant differences in contaminant migration rates or types and extent of controlling processes. Thus, we conclude that the laboratory results may be capable of extrapolation to actual disposal site conditions.

  16. Redox-inactive metal ions modulate the reactivity and oxygen release of mononuclear non-haem iron(III)-peroxo complexes.

    PubMed

    Bang, Suhee; Lee, Yong-Min; Hong, Seungwoo; Cho, Kyung-Bin; Nishida, Yusuke; Seo, Mi Sook; Sarangi, Ritimukta; Fukuzumi, Shunichi; Nam, Wonwoo

    2014-10-01

    Redox-inactive metal ions that function as Lewis acids play pivotal roles in modulating the reactivity of oxygen-containing metal complexes and metalloenzymes, such as the oxygen-evolving complex in photosystem II and its small-molecule mimics. Here we report the synthesis and characterization of non-haem iron(III)-peroxo complexes that bind redox-inactive metal ions, (TMC)Fe(III)-(μ,η(2):η(2)-O2)-M(n+) (M(n+) = Sr(2+), Ca(2+), Zn(2+), Lu(3+), Y(3+) and Sc(3+); TMC, 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane). We demonstrate that the Ca(2+) and Sr(2+) complexes showed similar electrochemical properties and reactivities in one-electron oxidation or reduction reactions. However, the properties and reactivities of complexes formed with stronger Lewis acidities were found to be markedly different. Complexes that contain Ca(2+) or Sr(2+) ions were oxidized by an electron acceptor to release O2, whereas the release of O2 did not occur for complexes that bind stronger Lewis acids. We discuss these results in the light of the functional role of the Ca(2+) ion in the oxidation of water to dioxygen by the oxygen-evolving complex.

  17. Redox-inactive metal ions modulate the reactivity and oxygen release of mononuclear non-haem iron(III)-peroxo complexes

    NASA Astrophysics Data System (ADS)

    Bang, Suhee; Lee, Yong-Min; Hong, Seungwoo; Cho, Kyung-Bin; Nishida, Yusuke; Seo, Mi Sook; Sarangi, Ritimukta; Fukuzumi, Shunichi; Nam, Wonwoo

    2014-10-01

    Redox-inactive metal ions that function as Lewis acids play pivotal roles in modulating the reactivity of oxygen-containing metal complexes and metalloenzymes, such as the oxygen-evolving complex in photosystem II and its small-molecule mimics. Here we report the synthesis and characterization of non-haem iron(III)-peroxo complexes that bind redox-inactive metal ions, (TMC)FeIII-(μ,η2:η2-O2)-Mn+ (Mn+ = Sr2+, Ca2+, Zn2+, Lu3+, Y3+ and Sc3+; TMC, 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane). We demonstrate that the Ca2+ and Sr2+ complexes showed similar electrochemical properties and reactivities in one-electron oxidation or reduction reactions. However, the properties and reactivities of complexes formed with stronger Lewis acidities were found to be markedly different. Complexes that contain Ca2+ or Sr2+ ions were oxidized by an electron acceptor to release O2, whereas the release of O2 did not occur for complexes that bind stronger Lewis acids. We discuss these results in the light of the functional role of the Ca2+ ion in the oxidation of water to dioxygen by the oxygen-evolving complex.

  18. Method of melting metals to reduce contamination from crucibles

    DOEpatents

    Banker, John G.; Wigginton, Hubert L.

    1977-01-01

    Contamination of metals from crucible materials during melting operations is reduced by coating the interior surface of the crucible with a ceramic non-reactive with the metallic charge and disposing a metal liner formed from a portion of the metallic charge within the coated crucible. The liner protects the ceramic coating during loading of the remainder of the charge and expands against the ceramic coating during heat-up to aid in sintering the coating.

  19. Further Development and Assessment of a Broadband Liner Optimization Process

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.

    2016-01-01

    The utilization of advanced fan designs (including higher bypass ratios) and shorter engine nacelles has highlighted a need for increased fan noise reduction over a broader frequency range. Thus, improved broadband liner designs must account for these constraints and, where applicable, take advantage of advanced manufacturing techniques that have opened new possibilities for novel configurations. This work focuses on the use of an established broadband acoustic liner optimization process to design a variable-depth, multi-degree of freedom liner for a high speed fan. Specifically, in-duct attenuation predictions with a statistical source model are used to obtain optimum impedance spectra over the conditions of interest. The predicted optimum impedance information is then used with acoustic liner modeling tools to design a liner aimed at producing impedance spectra that most closely match the predicted optimum values. The multi-degree of freedom design is carried through design, fabrication, and testing. In-duct attenuation predictions compare well with measured data and the multi-degree of freedom liner is shown to outperform a more conventional liner over a range of flow conditions. These promising results provide further confidence in the design tool, as well as the enhancements made to the overall design process.

  20. Wear of a sequentially annealed polyethylene acetabular liner

    PubMed Central

    Gascoyne, Trevor C; Petrak, Martin J; Turgeon, Thomas R; Bohm, Eric R

    2014-01-01

    Background and purpose We previously reported on a randomized controlled trial (RCT) that examined the effect of adding tobramycin to bone cement after femoral stem migration. The present study examined femoral head penetration into both conventional and highly crosslinked polyethylene acetabular liners in the same group of RCT patients, with a minimum of 5 years of postoperative follow-up. Patients and methods Linear penetration of the femoral head into an X3 (Stryker) crosslinked polyethylene (XLPE) liner was measured in 18 patients (19 hips) using radiostereometric analysis (RSA). Femoral head penetration was also measured in 6 patients (6 hips) with a conventional polyethylene liner (CPE), which served as a control group. Results The median proximal femoral head penetration in the XLPE group after 5.5 years was 0.025 mm with a steady-state penetration rate of 0.001 mm/year between year 1 and year 5. The CPE liner showed a median proximal head penetration of 0.274 mm after 7.2 years, at a rate of 0.037 mm/year. Interpretation The Trident X3 sequentially annealed XLPE liner shows excellent in vivo wear resistance compared to non-crosslinked CPE liners at medium-term implantation. The rate of linear head penetration in the XLPE liners after > 5 years of follow-up was 0.001 mm/year, which is in close agreement with the results of previous studies. PMID:25140986

  1. Thermographic inspection of pipes, tanks, and containment liners

    SciTech Connect

    Renshaw, Jeremy B. Muthu, Nathan; Lhota, James R.; Shepard, Steven M.

    2015-03-31

    Nuclear power plants are required to operate at a high level of safety. Recent industry and license renewal commitments aim to further increase safety by requiring the inspection of components that have not traditionally undergone detailed inspected in the past, such as tanks and liners. NEI 09-14 requires the inspection of buried pipes and tanks while containment liner inspections are required as a part of license renewal commitments. Containment liner inspections must inspect the carbon steel liner for defects - such as corrosion - that could threaten the pressure boundary and ideally, should be able to inspect the surrounding concrete for foreign material that could be in contact with the steel liner and potentially initiate corrosion. Such an inspection requires a simultaneous evaluation of two materials with very different material properties. Rapid, yet detailed, inspection results are required due to the massive size of the tanks and containment liners to be inspected. For this reason, thermal NDE methods were evaluated to inspect tank and containment liner mockups with simulated defects. Thermographic Signal Reconstruction (TSR) was utilized to enhance the images and provide detailed information on the sizes and shapes of the observed defects. The results show that thermographic inspection is highly sensitive to the defects of interest and is capable of rapidly inspecting large areas.

  2. Thermographic inspection of pipes, tanks, and containment liners

    NASA Astrophysics Data System (ADS)

    Renshaw, Jeremy B.; Lhota, James R.; Muthu, Nathan; Shepard, Steven M.

    2015-03-01

    Nuclear power plants are required to operate at a high level of safety. Recent industry and license renewal commitments aim to further increase safety by requiring the inspection of components that have not traditionally undergone detailed inspected in the past, such as tanks and liners. NEI 09-14 requires the inspection of buried pipes and tanks while containment liner inspections are required as a part of license renewal commitments. Containment liner inspections must inspect the carbon steel liner for defects - such as corrosion - that could threaten the pressure boundary and ideally, should be able to inspect the surrounding concrete for foreign material that could be in contact with the steel liner and potentially initiate corrosion. Such an inspection requires a simultaneous evaluation of two materials with very different material properties. Rapid, yet detailed, inspection results are required due to the massive size of the tanks and containment liners to be inspected. For this reason, thermal NDE methods were evaluated to inspect tank and containment liner mockups with simulated defects. Thermographic Signal Reconstruction (TSR) was utilized to enhance the images and provide detailed information on the sizes and shapes of the observed defects. The results show that thermographic inspection is highly sensitive to the defects of interest and is capable of rapidly inspecting large areas.

  3. CANMET Gasifier Liner Coupon Material Test Plan

    SciTech Connect

    Mark Fitzsimmons; Alan Darby; Fred Widman

    2005-10-30

    The test plan detailed in this topical report supports Task 1 of the project titled ''Development of Technologies and Capabilities for Coal Energy Resources - Advanced Gasification Systems Development (AGSD)''. The purpose of these tests is to verify that materials planned for use in an advanced gasifier pilot plant will withstand the environments in a commercial gasifier. Pratt & Whitney Rocketdyne (PWR) has developed and designed the cooled liner test assembly article that will be tested at CANMET Energy Technology Centre (CETC-O) in Ottawa, Ontario, Canada (CETC-O). The Test Plan TP-00364 is duplicated in its entirety, with formatting changes to comply with the format required for this Topical Report. The table of contents has been modified to include the additional material required by this topical report. Test Request example and drawings of non-proprietary nature are also included as appendices.

  4. A demonstration model for a selective and recyclable uptake of metals from water: Fe(III) ions complexation and release by a supported natural fluorescent chelator.

    PubMed

    Mureseanu, M; Renard, G; Galarneau, A; Lerner, D A

    2003-06-13

    We describe here the preliminary stage of development of a process aiming at the selective uptake and release of metal ions from water. The process envisioned involves the encapsulation of highly selective natural chelates secreted by bacteria or other living species in mesoporous solids that could be used as usual resins. To demonstrate the feasibility of the concept, we use a model system involving pyoverdin, a natural Fe(III) ions chelator from a Pseudomonas fluorescens strain, encapsulated in a mesoporous templated silica. For this model study, the native fluorescence of the chelator allows a simpler follow-up and quantification of the uptake and release processes. PMID:18969073

  5. Formed platelet combustor liner construction feasibility, phase A

    NASA Astrophysics Data System (ADS)

    Hayes, W. A.; Janke, D. E.

    1992-09-01

    Environments generated in high pressure liquid rocket engines impose severe requirements on regeneratively cooled combustor liners. Liners fabricated for use in high chamber pressures using conventional processes suffer from limitations that can impair operational cycle life and can adversely affect wall compatibility. Chamber liners fabricated using formed platelet technology provide an alternative to conventional regeneratively cooled liners (an alternative that has many attractive benefits). A formed platelet liner is made from a stacked assembly of platelets with channel features. The assembly is diffusion bonded into a flat panel and then three-dimensionally formed into a section of a chamber. Platelet technology permits the liner to have very precisely controlled and thin hot gas walls and therefore increased heat transfer efficiency. Further cooling efficiencies can be obtained through enhanced design flexibility. These advantages translate into increased cycle life and enhanced wall compatibility. The increased heat transfer efficiency can alternately be used to increase engine performance or turbopump life as a result of pressure drop reductions within the regeneratively cooled liner. Other benefits can be obtained by varying the materials of construction within the platelet liner to enhance material compatibility with operating environment or with adjoining components. Manufacturing cost savings are an additional benefit of a formed platelet liner. This is because of reduced touch labor and reduced schedule when compared to conventional methods of manufacture. The formed platelet technology is not only compatible with current state-of-the art combustion chamber structural support and manifolding schemes, it is also an enabling technology that allows the use of other high performance and potentially low cost methods of construction for the entire combustion chamber assembly. The contract under which this report is submitted contains three phases: (1) phase

  6. Formed platelet combustor liner construction feasibility, phase A

    NASA Technical Reports Server (NTRS)

    Hayes, W. A.; Janke, D. E.

    1992-01-01

    Environments generated in high pressure liquid rocket engines impose severe requirements on regeneratively cooled combustor liners. Liners fabricated for use in high chamber pressures using conventional processes suffer from limitations that can impair operational cycle life and can adversely affect wall compatibility. Chamber liners fabricated using formed platelet technology provide an alternative to conventional regeneratively cooled liners (an alternative that has many attractive benefits). A formed platelet liner is made from a stacked assembly of platelets with channel features. The assembly is diffusion bonded into a flat panel and then three-dimensionally formed into a section of a chamber. Platelet technology permits the liner to have very precisely controlled and thin hot gas walls and therefore increased heat transfer efficiency. Further cooling efficiencies can be obtained through enhanced design flexibility. These advantages translate into increased cycle life and enhanced wall compatibility. The increased heat transfer efficiency can alternately be used to increase engine performance or turbopump life as a result of pressure drop reductions within the regeneratively cooled liner. Other benefits can be obtained by varying the materials of construction within the platelet liner to enhance material compatibility with operating environment or with adjoining components. Manufacturing cost savings are an additional benefit of a formed platelet liner. This is because of reduced touch labor and reduced schedule when compared to conventional methods of manufacture. The formed platelet technology is not only compatible with current state-of-the art combustion chamber structural support and manifolding schemes, it is also an enabling technology that allows the use of other high performance and potentially low cost methods of construction for the entire combustion chamber assembly. The contract under which this report is submitted contains three phases: (1) phase

  7. Magnetized Target Fusion Driven by Plasma Liners

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Kirkpatrick, Ronald C.; Knapp, Charles E.; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    Magnetized target fusion is an emerging, relatively unexplored approach to fusion for electrical power and propulsion application. The physical principles of the concept are founded upon both inertial confinement fusion (ICF) and magnetic confinement fusion (MCF). It attempts to combine the favorable attributes of both these orthogonal approaches to fusion, but at the same time, avoiding the extreme technical challenges of both by exploiting a fusion regime intermediate between them. It uses a material liner to compress, heat and contain the fusion reacting plasma (the target plasma) mentally. By doing so, the fusion burn could be made to occur at plasma densities as high as six orders of magnitude higher than conventional MCF such as tokamak, thus leading to an approximately three orders of magnitude reduction in the plasma energy required for ignition. It also uses a transient magnetic field, compressed to extremely high intensity (100's T to 1000T) in the target plasma, to slow down the heat transport to the liner and to increase the energy deposition of charged-particle fusion products. This has several compounding beneficial effects. It leads to longer energy confinement time compared with conventional ICF without magnetized target, and thus permits the use of much lower plasma density to produce reasonable burn-up fraction. The compounding effects of lower plasma density and the magneto-insulation of the target lead to greatly reduced compressional heating power on the target. The increased energy deposition rate of charged-particle fusion products also helps to lower the energy threshold required for ignition and increasing the burn-up fraction. The reduction in ignition energy and the compressional power compound to lead to reduced system size, mass and R&D cost. It is a fusion approach that has an affordable R&D pathway, and appears attractive for propulsion application in the nearer term.

  8. Synthesis, characterization and investigation of the photophysical and photochemical properties of highly soluble novel metal-free, zinc(II), and indium(III) phthalocyanines substituted with 2,3,6-trimethylphenoxy moieties.

    PubMed

    Gürel, Ekrem; Pişkin, Mehmet; Altun, Selçuk; Odabaş, Zafer; Durmuş, Mahmut

    2015-04-01

    This work presents the synthesis and characterization of metal-free, zinc(II), and indium(III)acetate phthalocyanines substituted with 2,3,6-trimethylphenoxy groups at the peripheral and non-peripheral positions. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation and photodegradation under light irradiation) properties of these novel phthalocyanines and unsubstituted zinc(II) and indium(III)acetate phthalocyanines were investigated in dimethylformamide solution. The effects of the types of substituents and their positions and the variety of central metal ions on the phthalocyanine core on their spectroscopic, photophysical and photochemical properties were also determined. The studied 2,3,6-trimethylphenoxy substituted metal-free, zinc(II) and indium(III)acetate phthalocyanines especially indium(III)acetate derivatives exhibited appropriate photophysical and photochemical properties such as high singlet oxygen generation and these phthalocyanines can be potential Type II photosensitizers for photodynamic therapy in cancer applications.

  9. Removal of divalent heavy metals (Cd, Cu, Pb, and Zn) and arsenic(III) from aqueous solutions using scoria: kinetics and equilibria of sorption.

    PubMed

    Kwon, Jang-Soon; Yun, Seong-Taek; Lee, Jong-Hwa; Kim, Soon-Oh; Jo, Ho Young

    2010-02-15

    Kinetic and equilibrium sorption experiments were conducted on removal of divalent heavy metals (Pb(II), Cu(II), Zn(II), Cd(II)) and trivalent arsenic (As(III)) from aqueous solutions by scoria (a vesicular pyroclastic rock with basaltic composition) from Jeju Island, Korea, in order to examine its potential use as an efficient sorbent. The removal efficiencies of Pb, Cu, Zn, Cd, and As by the scoria (size=0.1-0.2mm, dose=60gL(-1)) were 94, 70, 63, 59, and 14%, respectively, after a reaction time of 24h under a sorbate concentration of 1mM and the solution pH of 5.0. A careful examination on ionic concentrations in sorption batches suggested that sorption behaviors of heavy metals onto scoria are mainly controlled by cation exchange. On the other hand, arsenic appeared to be sensitive to specific sorption onto hematite (a minor constituent of scoria). Equilibrium sorption tests indicated that the removal efficiency for heavy metals increases with increasing pH of aqueous solutions, which is resulted from precipitation as hydroxides. Similarly, multi-component systems containing heavy metals and arsenic showed that the arsenic removal increases with increasing pH of aqueous solutions, which can be attributed to coprecipitation with metal hydroxides. The empirically determined sorption kinetics were well fitted to a pseudo-second order model, while equilibrium sorption data for heavy metals and arsenic onto scoria were consistent with the Langmuir and Freundlich isotherms, respectively. Natural scoria studied in this work is an efficient sorbent for concurrent removal of divalent heavy metals and arsenic.

  10. A New Use for a Familiar Fold: the X-Ray Crystal Structure of GTP-Bound GTP Cyclohydrolase III From Methanocaldococcus Jannaschii Reveals a Two Metal Ion Catalytic Mechanism

    SciTech Connect

    Morrison, S.D.; Roberts, S.A.; Zegeer, A.M.; Montfort, W.R.; Bandarian, V.

    2009-05-26

    GTP cyclohydrolase (GCH) III from Methanocaldococcus jannaschii, which catalyzes the conversion of GTP to 2-amino-5-formylamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate (FAPy), has been shown to require Mg{sup 2+} for catalytic activity and is activated by monovalent cations such as K{sup +} and ammonium [Graham, D. E., Xu, H., and White, R. H. (2002) Biochemistry 41, 15074-15084]. The reaction is formally identical to that catalyzed by a GCH II ortholog (SCO 6655) from Streptomyces coelicolor; however, SCO 6655, like other GCH II proteins, is a zinc-containing protein. The structure of GCH III complexed with GTP solved at 2 {angstrom} resolution clearly shows that GCH III adopts a distinct fold that is closely related to the palm domains of phosphodiesterases, such as DNA polymerase I. GCH III is a tetramer of identical subunits; each monomer is composed of an N- and a C-terminal domain that adopt nearly superimposible structures, suggesting that the protein has arisen by gene duplication. Three metal ions were located in the active site, two of which occupy positions that are analogous to those occupied by divalent metal ions in the structures of a number of palm domain containing proteins, such as DNA polymerase I. Two conserved Asp residues that coordinate the metal ions, which are also found in palm domain containing proteins, are observed in GCH III. Site-directed variants (Asp{yields}Asn) of these residues in GCH III are less active than wild-type. The third metal ion, most likely a potassium ion, is involved in substrate recognition through coordination of O6 of GTP. The arrangement of the metal ions in the active site suggests that GCH III utilizes two metal ion catalysis. The structure of GCH III extends the repertoire of possible reactions with a palm fold to include cyclohydrolase chemistry.

  11. Forward and reverse (retro) iron(III) or gallium(III) desferrioxamine E and ring-expanded analogues prepared using metal-templated synthesis from endo-hydroxamic acid monomers.

    PubMed

    Lifa, Tulip; Tieu, William; Hocking, Rosalie K; Codd, Rachel

    2015-04-01

    A metal-templated synthesis (MTS) approach was used to preorganize the forward endo-hydroxamic acid monomer 4-[(5-aminopentyl)(hydroxy)amino]-4-oxobutanoic acid (for-PBH) about iron(III) in a 1:3 metal/ligand ratio to furnish the iron(III) siderophore for-[Fe(DFOE)] (ferrioxamine E) following peptide coupling. Substitution of for-PBH with the reverse (retro) hydroxamic acid analogue 3-(6-amino-N-hydroxyhexanamido)propanoic acid (ret-PBH) furnished ret-[Fe(DFOE)] (ret-ferrioxamine E). As isomers, for-[Fe(DFOE)] and ret-[Fe(DFOE)] gave identical mass spectrometry signals ([M + H(+)](+), m/zcalc 654.3, m/zobs 654.3), yet for-[Fe(DFOE)] eluted in a more polar window (tR = 23.44 min) than ret-[Fe(DFOE)] (tR = 28.13 min) on a C18 reverse-phase high-performance liquid chromatography (RP-HPLC) column. for-[Ga(DFOE)] (tR = 22.99 min) and ret-[Ga(DFOE)] (tR = 28.11 min) were prepared using gallium(III) as the metal-ion template and showed the same trend for the retention time. Ring-expanded analogues of for-[Fe(DFOE)] and ret-[Fe(DFOE)] were prepared from endo-hydroxamic acid monomers with one additional methylene unit in the amine-containing region, 4-[(6-aminohexyl)(hydroxy)amino]-4-oxobutanoic acid (for-HBH) or 3-(7-amino-N-hydroxyheptanamido)propanoic acid (ret-HBH), to give the corresponding tris(homoferrioxamine E) macrocycles, for-[Fe(HHDFOE)] or ret-[Fe(HHDFOE)] ([M + H(+)](+), m/zcalc 696.3, m/zobs 696.4). The MTS reaction using a constitutional isomer of for-HBH that transposed the methylene unit to the carboxylic acid containing region, 5-[(5-aminopentyl)(hydroxy)amino]-5-oxopentanoic acid (for-PPH), gave the macrocycle for-[Fe(HPDFOE)] in a yield significantly less than that for for-[Fe(HHDFOE)], with the gallium(III) analogue for-[Ga(HPDFOE)] unable to be detected. The work demonstrates the utility and limits of MTS for the assembly of macrocyclic siderophores from endo-hydroxamic acid monomers. Indirect measures (RP-HPLC order of elution, c log P values

  12. Application of the Ta liner technique to produce Ca beams at INFN-Legnaro National Laboratories (INFN-LNL)

    SciTech Connect

    Galatà, A. Sattin, M.; Manzolaro, M.; Martini, D.; Facco, A.; Tinschert, K.; Spaedtke, P.; Lang, R.; Kulevoy, T.

    2014-02-15

    The ECR ion sources are able to produce a wide variety of highly charged metallic ion beams thanks to the development of different techniques (ovens, sputtering, direct insertion, metal ions from volatile compounds (MIVOC)). In the case of the ovens, the sticking of the hot vapors on the surface of the plasma chamber leads to high material consumption rates. For elements like Ca, a tantalum liner inserted inside the chamber can be used to limit this phenomenon. The modeling of temperature distribution inside the chamber with and without the liner was carried out with COMSOL-multiphysics code. Results of simulation and the comparison with experiments performed at INFN-Legnaro National Laboratories with Ca beams are discussed.

  13. Interaction of Uranium Mill Tailings Leachate with Soils and Clay Liners

    SciTech Connect

    Gee, G. W.; Campbell, A. C.; Sherwood, D. R.; Strickert, R. G.; Phillips, S. J.

    1980-06-01

    This study evaluates leachate-soil interactions that will take place at the Morton Ranch for certain disposal alternatives. Laboratory tests were conducted to evaluate the following: 1) physical and chemical characteristics of geologic materials from the Morton Ranch. 2) physical and chemical characteristics of acid leach tailings and tallings solution, 3) leaching tests with selected tailings materials and leach solutions to evaluate the leachability of contaminants with time under specific disposal alternatives, 4) adsorption studies measuring the sorption characteristics of heavy metals and radionuclides on the geologic materials at Morton Ranch, 5) clay liner stability tests to evaluate effects of acid leachate on clay mineralogy and clay permeability.

  14. Lanthanide Metal-Organic Frameworks with Six-Coordinated Ln(III) Ions and Free Functional Organic Sites for Adsorptions and Extensive Catalytic Activities.

    PubMed

    Zhu, Yu; Zhu, Min; Xia, Li; Wu, Yunlong; Hua, Hui; Xie, Jimin

    2016-01-01

    Three chelating-amino-functionalized lanthanide metal-organic frameworks, Y-DDQ, Dy-DDQ and Eu-DDQ, were synthesized with a flexible dicarboxylate ligand based on quinoxaline (H2DDQ = N, N'-dibenzoic acid-2,3-diaminoquinoxaline). The three-dimensional framework is constructed by the H2DDQ linkers connecting the zigzag ladders, showing a net of sra topology. In the structures, one kind of Ln(III) ions metal centers are six-coordinated and thus can potentially behave as open metal sites (OMSs), while the free chelating amino groups can act as free functional organic sites (FOSs). The N2 and Ar adsorption behaviors indicate that these Ln-DDQ exhibits stable microporous frameworks with high surface area after remove of the solvents. Owing to presence of OMSs and FOSs, these MOFs show good ability of CO2, dyes captures and Lewis acid catalyst for cyanosilylation reaction. In view of the existing FOSs in the framework, Pd NPs were immobilized onto the MOFs through graft interactions between free chelating amino groups and metal ions precursor using postsynthetic modification. The well dispersed Pd@Ln-DDQs exhibit efficient and recyclable catalytic reduction of 4-nitrophenol to 4-aminophenol, and they can also act as an excellent catalyst for Suzuki-Miyaura cross-coupling reactions with the exposed Pd NPs. PMID:27431731

  15. Lanthanide Metal-Organic Frameworks with Six-Coordinated Ln(III) Ions and Free Functional Organic Sites for Adsorptions and Extensive Catalytic Activities

    PubMed Central

    Zhu, Yu; Zhu, Min; Xia, Li; Wu, Yunlong; Hua, Hui; Xie, Jimin

    2016-01-01

    Three chelating-amino-functionalized lanthanide metal-organic frameworks, Y-DDQ, Dy-DDQ and Eu-DDQ, were synthesized with a flexible dicarboxylate ligand based on quinoxaline (H2DDQ = N, N′-dibenzoic acid-2,3-diaminoquinoxaline). The three-dimensional framework is constructed by the H2DDQ linkers connecting the zigzag ladders, showing a net of sra topology. In the structures, one kind of Ln(III) ions metal centers are six-coordinated and thus can potentially behave as open metal sites (OMSs), while the free chelating amino groups can act as free functional organic sites (FOSs). The N2 and Ar adsorption behaviors indicate that these Ln-DDQ exhibits stable microporous frameworks with high surface area after remove of the solvents. Owing to presence of OMSs and FOSs, these MOFs show good ability of CO2, dyes captures and Lewis acid catalyst for cyanosilylation reaction. In view of the existing FOSs in the framework, Pd NPs were immobilized onto the MOFs through graft interactions between free chelating amino groups and metal ions precursor using postsynthetic modification. The well dispersed Pd@Ln-DDQs exhibit efficient and recyclable catalytic reduction of 4-nitrophenol to 4-aminophenol, and they can also act as an excellent catalyst for Suzuki-Miyaura cross-coupling reactions with the exposed Pd NPs. PMID:27431731

  16. Lanthanide Metal-Organic Frameworks with Six-Coordinated Ln(III) Ions and Free Functional Organic Sites for Adsorptions and Extensive Catalytic Activities

    NASA Astrophysics Data System (ADS)

    Zhu, Yu; Zhu, Min; Xia, Li; Wu, Yunlong; Hua, Hui; Xie, Jimin

    2016-07-01

    Three chelating-amino-functionalized lanthanide metal-organic frameworks, Y-DDQ, Dy-DDQ and Eu-DDQ, were synthesized with a flexible dicarboxylate ligand based on quinoxaline (H2DDQ = N, N‧-dibenzoic acid-2,3-diaminoquinoxaline). The three-dimensional framework is constructed by the H2DDQ linkers connecting the zigzag ladders, showing a net of sra topology. In the structures, one kind of Ln(III) ions metal centers are six-coordinated and thus can potentially behave as open metal sites (OMSs), while the free chelating amino groups can act as free functional organic sites (FOSs). The N2 and Ar adsorption behaviors indicate that these Ln-DDQ exhibits stable microporous frameworks with high surface area after remove of the solvents. Owing to presence of OMSs and FOSs, these MOFs show good ability of CO2, dyes captures and Lewis acid catalyst for cyanosilylation reaction. In view of the existing FOSs in the framework, Pd NPs were immobilized onto the MOFs through graft interactions between free chelating amino groups and metal ions precursor using postsynthetic modification. The well dispersed Pd@Ln-DDQs exhibit efficient and recyclable catalytic reduction of 4-nitrophenol to 4-aminophenol, and they can also act as an excellent catalyst for Suzuki-Miyaura cross-coupling reactions with the exposed Pd NPs.

  17. Optical and electrochemical characteristics of ethylenediamine complexes of Pt(II) and Ir(III) with metalated 2-phenyl- and 2-naphthylbenzothiazole

    NASA Astrophysics Data System (ADS)

    Katlenok, E. A.; Balashev, K. P.

    2016-05-01

    The cyclometalated complexes [Pt(C^N)En]PF6 and [Ir(C^N)2En]PF6 ((C^N)- are deprotonated forms of 2-phenylbenzothiazole or 2-naphthylbenzothiazole and En is ethylenediamine) are studied by 1H NMR, IR, electronic absorption, and emission spectroscopy, as well as by voltammetry. Metalation of heterocyclic ligands leads to the formation of five-membered {M(C^N)} cycles in the composition of squareplanar Pt(II) complexes and octahedral Ir(III) complexes of the cis-C,C structure. A bathochromic shift of the metal-to-cyclometalated ligand charge transfer bands and a decrease in the potential difference between the single-electron waves of metal-centered oxidation and ligand-centered reduction of complexes upon substitution of 2-phenylbenzothiazole by 2-naphthylbenzothiazole and of Pt(II) by Ir(II) are shown. The phosphorescence of complexes in the visible region is assigned to the radiative transition from the metal-modified intraligand electronic excited state.

  18. Two heterometallic-organic frameworks composed of iron(III)-salen-based ligands and d(10) metals: gas sorption and visible-light photocatalytic degradation of 2-chlorophenol.

    PubMed

    Li, Jing; Yang, Jin; Liu, Ying-Ying; Ma, Jian-Fang

    2015-03-01

    Two examples of heterometallic-organic frameworks (HMOFs) composed of dicarboxyl-functionalized Fe(III)-salen complexes and d(10) metals (Zn, Cd), [Zn2(Fe-L)2(μ2-O)(H2O)2]⋅4 DMF⋅4 H2O (1) and [Cd2(Fe-L)2(μ2-O)(H2O)2]⋅2 DMF⋅H2O (2) (H4L = 1,2-cyclohexanediamino-N,N'-bis(3-methyl-5-carboxysalicylidene), have been synthesized and structurally characterized. In 1 and 2, each square-pyramidal Fe(III) atom is embedded in the [N2O2] pocket of an L(4-) anion, and these units are further bridged by a μ2-O anion to give an (Fe-L)2(μ2-O) dimer. The two carboxylate groups of each L(4-) anion bridge Zn(II) or Cd(II) atoms to afford a 3D porous HMOF. The gas sorption and magnetic properties of 1 and 2 have been studied. Remarkably, 1 and 2 show activity for the photocatalytic degradation of 2-chlorophenol (2-CP) under visible-light irradiation, which, to the best of our knowledge, is the first time that this has been observed for Fe(III)-salen-based HMOFs.

  19. Subscale hot-fire testing of a formed platelet liner

    NASA Technical Reports Server (NTRS)

    Elam, Sandra K.; Hayes, William A.

    1993-01-01

    To investigate low-cost options for fabricating main combustion chambers, formed platelet liners are being developed. The savings in manufacturing time and cost associated with platelet liners are accompanied by promising thermal advantages, such as lower-wall temperatures and increased cycle life. A subscale liner was tested by NASA at Marshall Space Flight Center (MSFC) to demonstrate its thermal performance. Testing to date has provided chamber pressures up to 2524 psia, while a maximum chamber pressure of 2700 psia is planned. In general, the liner has remained in good condition and performed well, with only minor areas of localized roughening. Data from this subscale test program is being used to develop a full size chamber for testing on a Space Shuttle Main Engine at MSFC in 1994.

  20. Acoustic Liner Drag: A Parametric Study of Conventional Configurations

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.; Jones, Michael G.

    2015-01-01

    Interest in the characterization of the aerodynamic drag performance of acoustic liners has increased in the past several years. This paper details experiments in NASA Langley's Grazing Flow Impedance Tube to quantify the relative drag of several conventional perforate-over-honeycomb liner configurations. For a fixed porosity, facesheet hole diameter and cavity depth are varied to study the effect of each. These configurations are selected to span the range of conventional liner geometries used in commercial aircraft engines. Detailed static pressure and acoustic measurements are made for grazing flows up to M=0.5 at 140 dB SPL for tones between 400 and 2800 Hz. These measurements are used to calculate a resistance factor (?) for each configuration. Analysis shows a correlation between perforate hole size and the resistance factor but cavity depth seems to have little influence. Acoustic effects on liner drag are observed to be limited to the lower Mach numbers included in this investigation.

  1. IET. Stack interior. Masons lay fire brick liner, leaving air ...

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

    IET. Stack interior. Masons lay fire brick liner, leaving air layer between bricks and concrete wall. Date: May 20, 1955. INEEL negative no. 55-1306 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  2. High-speed velocimetry inside imploding cylindrical liners

    NASA Astrophysics Data System (ADS)

    Dolan, Daniel; Lemke, Ray; Dalton, Devon; Harding, Eric; McBride, Ryan; Martin, Matthew; Blue, Brent; Walker, Scott

    2014-03-01

    Dynamic planar compression is conceptually simple but difficult to maintain at extreme pressure (>5 Mbar). Higher pressures are attainable with imploding cylindrical liners, using Photonic Doppler velocimetry (PDV) to track the liner interior. PDV measures Doppler shift directly--1 GHz of beat frequency for every 1 km/s of velocity--requiring a special ``leapfrog'' approach for liners traveling in excess of 20 km/s. Single-point and multi-point PDV measurements have been performed in aluminum, beryllium, and tantalum liners under ramp compression, and the technique can readily applied to other implosion experiments. Combined with electrical current diagnostics, these measurements test thermodynamic equations of state at pressures up to 10 MBar and beyond. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85.

  3. Experimental Impedance of Single Liner Elements with Bias Flow

    NASA Technical Reports Server (NTRS)

    Follet, J. I.; Betts, J. F.; Kelly, Jeffrey J.; Thomas, Russell H.

    2000-01-01

    An experimental investigation was conducted to generate a high quality database, from which the effects of a mean bias flow on the acoustic impedance of lumped-element single-degree-of-freedom liners was determined. Acoustic impedance measurements were made using the standard two-microphone method in the NASA Langley Normal Incidence Tube. Each liner consisted of a perforated sheet with a constant-area cavity. Liner resistance was shown to increase and to become less frequency and sound pressure level dependent as the bias flow was increased. The resistance was also consistently lower for a negative bias flow (suction) than for a positive bias flow (blowing) of equal magnitude. The slope of the liner reactance decreased with increased flow.

  4. Method of repairing a wellbore liner for sand control

    SciTech Connect

    Dees, J.M.

    1992-10-13

    This patent describes a method of repairing a damaged wellbore liner for controlling sand and other fine materials. It comprises: positioning a quantity of fluid resin material in alignment with the portion of the wellbore liner to be repaired; positioning a gas generator in proximity with the fluid resin material; actuating the gas generator to increase wellbore pressure in a substantially instantaneous manner to a pressure substantially in excess of well pressure to force the fluid resin material from the wellbore into the damaged area of the wellbore liner; and subsequently polymerizing the resin material to form a consolidated, porous permeable matrix that allows the flow of production fluid into the well while preventing the flow of sand, or other fine materials into the well through the previously damaged area of the wellbore liner.

  5. Cu(II) and Zn(II) adsorption capacity of three different clay liner materials.

    PubMed

    Musso, T B; Parolo, M E; Pettinari, G; Francisca, F M

    2014-12-15

    Sorption of Cu(II) and Zn(II) on three natural clays meeting the international requirements for use as liners was evaluated by means of batch tests. The purpose of this research was to determine the retention capacities of the clays for metal cations commonly present in urban solid waste leachates. The pH and ionic strength conditions were set at values frequently found in real leachates. The changes observed in the XRD patterns and FTIR spectra upon adsorption can be considered an evidence of clay-metal electrostatic interaction. The Langmuir model was found to best describe the sorption processes, offering maximum sorption capacities from 8.16 to 56.89 mg/g for Cu(II) and from 49.59 to 103.83 mg/g for Zn(II). All samples remove more Zn(II) than Cu(II), which may be related to the different geometry of the hydrated Cu(II) cation. The total amount of metal sorption was strongly influenced by the total specific surface area, the presence of carbonates and the smectite content of the clays. In addition to their known quality as physical barriers, the adsorbed amounts obtained indicate the suitability of the tested clays to contribute to the retardation of Cu(II) and Zn(II) transport through clay liners.

  6. Configuration Effects on Acoustic Performance of a Duct Liner

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Brown, Martha C.; Jones, Michael G.; Nark, Douglas; Howerton, Brian M.

    2008-01-01

    Continued success in aircraft engine noise reduction necessitates ever more complete understanding of the effect that flow path geometry has on sound propagation in the engine. The Curved Duct Test Rig (CDTR) has been developed at NASA Langley Research Center to investigate sound propagation through a duct of comparable size (approximately the gap of GE90) and physical characteristics to the aft bypass duct of typical aircraft engines. The liner test section is designed to mimic the outer/inner walls of an engine exhaust bypass duct that has been unrolled circumferentially. Experiments to investigate the effect of curvature along the flow path on the acoustic performance of a test liner are performed in the CDTR and reported in this paper. Flow paths investigated include both straight and curved with offsets from the inlet to the discharge plane of and 1 duct width, respectively. The test liners are installed on the side walls of the liner test section. The liner samples are perforate over honeycomb core, which design is typical of liners installed in aircraft nacelles. In addition to fully treated side walls, combinations of treated and acoustically rigid walls are investigated. While curvature in the hard wall duct is found not to reduce the incident sound significantly, it does cause mode scattering. It is found that asymmetry of liner treatment causes scattering of the incident mode into less attenuated modes, which degrades the overall liner attenuation. It is also found that symmetry of liner treatment enhances liner performance by eliminating scattering into less attenuated modes. Comparisons of measured liner attenuation with numerical results predicted by an analytic model based on the parabolic approximation (CDUCT-LaRC) have also been made and are reported in this paper. The effect of curvature in the rigid wall configuration estimated by CDUCT-LaRC is similar to the observed results, and the mode scattering seen in the measurements also occurs in the

  7. The Subaru FMOS Galaxy Redshift Survey (FastSound). III. The mass-metallicity relation and the fundamental metallicity relation at z ˜ 1.4*

    NASA Astrophysics Data System (ADS)

    Yabe, Kiyoto; Ohta, Kouji; Akiyama, Masayuki; Bunker, Andrew; Dalton, Gavin; Ellis, Richard; Glazebrook, Karl; Goto, Tomotsugu; Imanishi, Masatoshi; Iwamuro, Fumihide; Okada, Hiroyuki; Shimizu, Ikkoh; Takato, Naruhisa; Tamura, Naoyuki; Tonegawa, Motonari; Totani, Tomonori

    2015-12-01

    We present the results from a large near-infrared spectroscopic survey made with Subaru/FMOS (FastSound) consisting of ˜ 4000 galaxies at z ˜ 1.4 with significant Hα detection. We measure the gas-phase metallicity from the [N II]λ6583/Hα emission line ratio of the composite spectra in various stellar mass and star-formation rate bins. The resulting mass-metallicity relation generally agrees with previous studies obtained in a similar redshift range to that of our sample. No clear dependence of the mass-metallicity relation on star-formation rate is found. Our result at z ˜ 1.4 is roughly in agreement with the fundamental metallicity relation at z ˜ 0.1 with a fiber aperture corrected star-formation rate. We detect significant [S II]λλ6716,6731 emission lines from the composite spectra. The electron density estimated from the [S II]λλ6716,6731 line ratio ranges from 10-500 cm-3, which generally agrees with that of local galaxies. On the other hand, the distribution of our sample on [N II]λ6583/Hα vs. [S II]λλ6716,6731/Hα is different to that found locally. We estimate the nitrogen-to-oxygen abundance ratio (N/O) from the N2S2 index, and find that the N/O in galaxies at z ˜ 1.4 is significantly higher than the local values at a fixed metallicity and stellar mass. The metallicity at z ˜ 1.4 recalculated with this N/O enhancement taken into account decreases by 0.1-0.2 dex. The resulting metallicity is lower than the local fundamental metallicity relation.

  8. Flap Side Edge Liners for Airframe Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Khorrami, Mehdi R. (Inventor); Choudhari, Meelan M. (Inventor); Howerton, Brian M. (Inventor)

    2014-01-01

    One or more acoustic liners comprising internal chambers or passageways that absorb energy from a noise source on the aircraft are disclosed. The acoustic liners may be positioned at the ends of flaps of an aircraft wing to provide broadband noise absorption and/or dampen the noise producing unsteady flow features, and to reduce the amount of noise generated due to unsteady flow at the inboard and/or outboard end edges of a flap.

  9. Landing Gear Door Liners for Airframe Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, Michael G. (Inventor); Howerton, Brian M. (Inventor); Van De Ven, Thomas (Inventor)

    2014-01-01

    A landing gear door for retractable landing gear of aircraft includes an acoustic liner. The acoustic liner includes one or more internal cavities or chambers having one or more openings that inhibit the generation of sound at the surface and/or absorb sound generated during operation of the aircraft. The landing gear door may include a plurality of internal chambers having different geometries to thereby absorb broadband noise.

  10. Effects of Flow Profile on Educed Acoustic Liner Impedance

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Watson, Willie r.; Nark, Douglas M.

    2010-01-01

    This paper presents results of an investigation of the effects of shear flow profile on impedance eduction processes employed at NASA Langley. Uniform and 1-D shear-flow propagation models are used to educe the acoustic impedance of three test liners based on aeroacoustic data acquired in the Langley Grazing Flow Impedance Tube, at source levels of 130, 140 and 150 dB, and at centerline Mach numbers of 0.0, 0.3 and 0.5. A ceramic tubular, calibration liner is used to evaluate the propagation models, as this liner is expected to be insensitive to SPL, grazing flow Mach number, and flow profile effects. The propagation models are then used to investigate the effects of shear flow profile on acoustic impedances educed for two conventional perforate-over-honeycomb liners. Results achieved with the uniform-flow models follow expected trends, but those educed with the 1-D shear-flow model do not, even for the calibration liner. However, when the flow profile used with the shear-flow model is varied to increase the Mach number gradient near the wall, results computed with the shear-flow model are well matched to those achieved with the uniform-flow model. This indicates the effects of flow profile on educed acoustic liner impedance are small, but more detailed investigations of the flow field throughout the duct are needed to better understand these effects.

  11. Computer method for design of acoustic liners for turbofan engines

    NASA Technical Reports Server (NTRS)

    Minner, G. L.; Rice, E. J.

    1976-01-01

    A design package is presented for the specification of acoustic liners for turbofans. An estimate of the noise generation was made based on modifications of existing noise correlations, for which the inputs are basic fan aerodynamic design variables. The method does not predict multiple pure tones. A target attenuation spectrum was calculated which was the difference between the estimated generation spectrum and a flat annoyance-weighted goal attenuated spectrum. The target spectrum was combined with a knowledge of acoustic liner performance as a function of the liner design variables to specify the acoustic design. The liner design method at present is limited to annular duct configurations. The detailed structure of the liner was specified by combining the required impedance (which is a result of the previous step) with a mathematical model relating impedance to the detailed structure. The design procedure was developed for a liner constructed of perforated sheet placed over honeycomb backing cavities. A sample calculation was carried through in order to demonstrate the design procedure, and experimental results presented show good agreement with the calculated results of the method.

  12. The Nature of the Energy Source in LINER's

    NASA Technical Reports Server (NTRS)

    Colina, L.; Koratkar, Anuradha

    1996-01-01

    LINER's (low-ionization nuclear emission-line regions) are found in about 30% of all bright galaxies, including luminous infrared galaxies. They form a heterogeneous class powered by a variety of ionizing mechanisms such as low-luminosity AGNs (active galactic nuclei), starbursts, shocks, or any combination of these. In early-type spirals, LINER's are powered by a low-luminosity AGN, or by an AGN surrounded by circumnuclear star-forming regions. In luminous infrared galaxies, LINER's are powered by starbursts with associated wind-related extended shocks, and an AGN may play a minor role, if any. LINER's in some FR I radio galaxies show strong evidence for the presence of a massive central black hole, and there are indications for the existence of shocks in the nuclear disks of these galaxies. Yet, the dominant ionizing mechanism for LINER's in radio-quiet ellipticals and FR I host galaxies is still unclear. Multifrequency high spatial resolution imaging and spectroscopy are essential to discriminate among the different ionizing mechanisms present in LINER's.

  13. Composite Liner, Multi-Megabar Shock Driver Development

    SciTech Connect

    Cochrane, J.C. Jr.; Bartsch, R.R.; Clark, D.A.; Morgan, D.V.; Anderson, W.E.; Lee, H.; Bowers, R.L.; Atchison, W.L.; Oona, H.; Stokes, J.L.; Veeser, L.R.; Broste, W.B.

    1998-10-18

    The multi-megabar shock driver development is a series of experiments in support of the Los Alamos High Energy Density Physics Experimental Program. Its purpose is to develop techniques to impact a uniform, stable, composite liner upon a high Z target to produce a multi-megabar shock for EOS studies. To date, experiments have been done on the Pegasus II capacitor bank with a current of {approximately}12MA driving the impactor liner. The driving field is {approximately}200 T at the target radius of 1cm. Data will be presented on the impactor liner. The driving field is {approximately}200 T at the target radius of 1 cm. Data will be presented on the stability and uniformity of the impactor liner when it impacts the target cylinder. Three experiments have been done with emphasis on liner development. Shock pressures greater than a megabar have been done with emphasis on liner development. Shock pressures greater than a megabar have been produced with an Al target cylinder. A Pt target cylinder should produce shock pressures in th e 5-megabar range.

  14. Self-assembly of Terbium(III)-based metal-organic complexes with two-photon absorbing active.

    PubMed

    Li, Dandan; Shao, Nanqi; Sun, Xianshun; Zhang, Guocui; Li, Shengli; Zhou, Hongping; Wu, Jieying; Tian, Yupeng

    2014-12-10

    Hybrid complexes based on D-π-A type dyes p-aminostyryl-pyridinum and Terbium(III) complex anion (1, 2) have been synthesized by ionic exchange reaction. Meanwhile two different alkyl-substituted amino groups were used as electron donors in organic dyes cations. The synthesized complexes were characterized by element analysis. In addition, the structural features of them were systematic studied by single crystal X-ray diffraction analysis. Their linear properties have been systematically investigated by absorption spectra and fluorescence, the results show that the energy transfer takes place from the trans-4-[4'-(N,N-diethylamino)styryl]-N-methyl pyridinium (2') cation to Tb(III). In addition, complex 2 exhibit a large two-photon absorption coefficient β: 0.044cm/GW at 710nm.

  15. Transition metal quinone-thiosemicarbazone complexes 3: Spectroscopic characterizations of spin-mixed iron (III) of naphthoquinone-thiosemicarbazones.

    PubMed

    Chikate, Rajeev C; Padhye, Subhash B

    2007-04-01

    An interesting series of iron (III) complexes with naphthoquinone-thiosemicarbazones are synthesized and physico-chemically characterized by elemental analysis, UV-vis, IR, EPR and magnetic susceptibility measurements. They possess a cationic octahedral [FeL2]+ species and a tetrahedral [FeCl4]- anion and exhibit unusual spin-mixed states involving high-spin and low-spin ferric centers as revealed from magnetic behavior with significant amount of exchange interactions mediated by intermolecular associations. The magnetic susceptibility data is fitted with S1=5/2 and S2=1/2 Heisengberg's exchange coupled model; H=-2JS1S2 and the magnetic exchange interactions are found to be of the order of -13.6 cm-1 indicating the moderate coupling between two paramagnetic centers present in different chemical and structural environment. The presence of spin-paired iron (III) cation having dxz2dxz2dxz1 ground state is revealed from the EPR spectra with three prominent peaks while the high-spin tetrahedral iron (III) anion exhibits characteristics g=4 signal whose intensity increases with lowering the temperature suggesting its influence on the magnetic properties of the complex molecule. FTIR measurements indicate tridentate ONS donor systems involving quinone/hydroxyl oxygen, imine/hydrazinic nitrogen and thione/thiol sulfur atoms as binding sites for naphthoquinone-thiosemicarbazones. PMID:16876470

  16. Electric Plasma Arc-Lamp Combustor Liner Durability Test System Developed

    NASA Technical Reports Server (NTRS)

    Goldsby, Jon C.; Halbig, Michael C.

    2000-01-01

    current. One of the special features of this configuration is the creation of hoop stress states within the cylinder, which up this point have not been obtainable in planar coupon tests. This facility will allow various operational modes, including accelerated tests of thermal transients simulating the effects of repeated engine ignition as well as prescribed thermal and mechanical histories to simulate various duty cycle profiles. Tests can now be performed on thermal-barrier-coated metallic liners and ceramic composite liners that require a combination of high heat flux and controlled mechanical stresses.

  17. Hydraulic conductivity of desiccated geosynthetic clay liners

    SciTech Connect

    Boardman, B.T.; Daniel, D.E.

    1996-03-01

    Large-scale tests were performed to determine the effect of a cycle of wetting and drying on the hydraulic conductivity of several geosynthetic clay liners (GCLs). The GCLs were covered with 0.6 m of pea gravel and permeated with water. After steady seepage had developed, the water was drained away, and the GCL was desiccated by circulating heated air through the overlying gravel. The drying caused severe cracking in the bentonite component of the GCLs. The GCLs were again permeated with water. As the cracked bentonite hydrated and swelled, the hydraulic conductivity slowly decreased from an initially high value. The long-term, steady value of hydraulic conductivity after the wetting and drying cycle was found to be essentially the same as the value for the undesiccated GCL. It is concluded that GCLs possess the ability to self-heal after a cycle of wetting and drying, which is important for applications in which there may be alternate wetting and drying of a hydraulic barrier (e.g. within a landfill final cover).

  18. Geosynthetic clay liners - slope stability field study

    SciTech Connect

    Carson, D.A.; Daniel, D.E.; Koerner, R.M.; Bonaparte, R.

    1997-12-31

    A field research project was developed to examine the internal shear performance of geosynthetic clay liners (GCLs). Several combinations of cross sections were assembled using GCL materials that were available at the time of project initiation. The cross sections utilized were intended to simulate landfill cover applications. Thirteen (13) resulting test plots were constructed on two different slope angles, and each plot is instrumented for physical displacement and soil moisture characteristics. Test plots were constructed in a manner that dictated the shear plane in the clay portion of the GCL product. The project purpose is to assess field performance and to verify design parameters associated with the application of GCLs in waste containment applications. Interim research data shows that test slopes on 2H:1V show global deformation, but little internal shear evidence, and the 3H:1V slopes show little deformation at approximately 650 days. The research is ongoing, and this paper presents the most recent information available from the project.

  19. Impoundment liner repair by electrophoresis of clay

    SciTech Connect

    Yeung, A.T.; Corapcioglu, M.Y.; Stallard, W.M.; Chung, M.

    1997-10-01

    Electrophoresis of clay particles from dilute suspensions is an innovative technology to seal leaks in operating surface impoundments that does not require removal of impoundment contents, exposure of workers to contaminants, or prior knowledge of the leak locations. A suspension of clay particles is added to the impoundment liquid. A cathode (negative electrode) is placed inside and an anode (positive electrode) is placed outside the leaking impoundment. A direct current (DC) electric field is imposed externally across the geomembrane liner through the leaks. The clay particles migrate to the leaks under the influence of the imposed electric field to form a clay cake seal. The results of laboratory experiments to evaluate the use of a DC electric field to direct migration of clay particles into a leak and the hydraulic integrity of the resulting seal are presented in this paper. The effects of clay type, clay particle concentration in suspension, size of leak, and electric field strength on the migration of clay particles and process of cake formation are evaluated. The sealing effectiveness and internal structure of the resulting clay cakes are examined by hydraulic conductivity measurements and nuclear magnetic resonance imaging. Electrophoretic mobilities of bentonite particles in different chemical environments were also measured to evaluate the feasibility of the technology in practical situations.

  20. Redox-inactive metal ions modulate the reactivity and oxygen release of mononuclear non-haem iron(III)–peroxo complexes

    DOE PAGES

    Bang, Suhee; Lee, Yong -Min; Hong, Seungwoo; Cho, Kyung -Bin; Nishida, Yusuke; Seo, Mi Sook; Sarangi, Ritimukta; Fukuzumi, Shunichi; Nam, Wonwoo

    2014-09-14

    Redox-inactive metal ions that function as Lewis acids play pivotal roles in modulating the reactivity of oxygen-containing metal complexes and metalloenzymes, such as the oxygen-evolving complex in photosystem II and its small-molecule mimics. Here we report the synthesis and characterization of non-haem iron(III)–peroxo complexes that bind redox-inactive metal ions, (TMC)FeIII–(μ,η2:η2-O2)–Mn+ (Mn+ = Sr2+, Ca2+, Zn2+, Lu3+, Y3+ and Sc3+; TMC, 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane). We demonstrate that the Ca2+ and Sr2+ complexes showed similar electrochemical properties and reactivities in one-electron oxidation or reduction reactions. However, the properties and reactivities of complexes formed with stronger Lewis acidities were found to be markedly different. Inmore » conclusion, complexes that contain Ca2+ or Sr2+ ions were oxidized by an electron acceptor to release O2, whereas the release of O2 did not occur for complexes that bind stronger Lewis acids. Furthermore, we discuss these results in the light of the functional role of the Ca2+ ion in the oxidation of water to dioxygen by the oxygen-evolving complex.« less

  1. Tokamak with liquid metal for inducing toroidal electrical field

    DOEpatents

    Ohkawa, Tihiro

    1981-01-01

    A tokamak apparatus includes a vessel for defining a reservoir and confining liquid therein. A toroidal liner disposed within said vessel defines a toroidal space within the liner confines gas therein. Liquid metal fills the reservoir outside the liner. A magnetic field is established in the liquid metal to develop magnetic flux linking the toroidal space. The gas is ionized. The liquid metal and the toroidal space are moved relative to one another transversely of the space to generate electric current in the ionized gas in the toroidal space about its major axis and thereby heat plasma developed in the toroidal space.

  2. Selectivity of the highly preorganized tetradentate ligand 2,9-di(pyrid-2-yl)-1,10-phenanthroline for metal ions in aqueous solution, including lanthanide(III) ions and the uranyl(VI) cation.

    PubMed

    Carolan, Ashley N; Cockrell, Gregory M; Williams, Neil J; Zhang, Gang; VanDerveer, Donald G; Lee, Hee-Seung; Thummel, Randolph P; Hancock, Robert D

    2013-01-01

    Some metal ion complexing properties of DPP (2,9-Di(pyrid-2-yl)-1,10-phenanthroline) are reported with a variety of Ln(III) (Lanthanide(III)) ions and alkali earth metal ions, as well as the uranyl(VI) cation. The intense π-π* transitions in the absorption spectra of aqueous solutions of 10(-5) M DPP were monitored as a function of pH and metal ion concentration to determine formation constants of the alkali-earth metal ions and Ln(III) (Ln = lanthanide) ions. It was found that log K(1)(DPP) for the Ln(III) ions has a peak at Ln(III) = Sm(III) in a plot of log K(1) versus 1/r(+) (r(+) = ionic radius for 8-coordination). For Ln(III) ions larger than Sm(III), there is a steady rise in log K(1) from La(III) to Sm(III), while for Ln(III) ions smaller than Sm(III), log K(1) decreases slightly to the smallest Ln(III) ion, Lu(III). This pattern of variation of log K(1) with varying size of Ln(III) ion was analyzed using MM (molecular mechanics) and DFT (density functional theory) calculations. Values of strain energy (∑U) were calculated for the [Ln(DPP)(H(2)O)(5)](3+) and [Ln(qpy)(H(2)O)(5)](3+) (qpy = quaterpyrdine) complexes of all the Ln(III) ions. The ideal M-N bond lengths used for the Ln(III) ions were the average of those found in the CSD (Cambridge Structural Database) for the complexes of each of the Ln(III) ions with polypyridyl ligands. Similarly, the ideal M-O bond lengths were those for complexes of the Ln(III) ions with coordinated aqua ligands in the CSD. The MM calculations suggested that in a plot of ∑U versus ideal M-N length, a minimum in ∑U occurred at Pm(III), adjacent in the series to Sm(III). The significance of this result is that (1) MM calculations suggest that a similar metal ion size preference will occur for all polypyridyl-type ligands, including those containing triazine groups, that are being developed as solvent extractants in the separation of Am(III) and Ln(III) ions in the treatment of nuclear waste, and (2) Am(III) is very

  3. Complexation of nitrogen and sulphur donor Schiff's base ligand to Cr(III) and Ni(II) metal ions: Synthesis, spectroscopic and antipathogenic studies

    NASA Astrophysics Data System (ADS)

    Sharma, Amit Kumar; Chandra, Sulekh

    2011-01-01

    2,6-Diacetyl pyridine based ligand was synthesized by the reaction of 2,6-diacetyl pyridine with thiocarbohydrazide in presence of acetic acid. The coordination compounds with Cr(III) and Ni(II) metal ions having [Cr(L)X]X 2 and [Ni(L)X]X compositions (where L = ligand and X = NO 3-, Cl - and CH 3COO -) were synthesized and characterized by physicochemical and spectral studies. The studies like elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, UV-Vis, NMR, mass and EPR reveal that the complexes are octahedral. The compounds were examined against the pathogenic fungal and bacterial strains like Alternaria brassicae, Aspergillus niger, Fusarium oxysporum, Xanthomonas compestris and Pseudomonas aeruginosa. A. niger causes the diseases Apergillosis and Otomycosis in humans.

  4. Novel mixed metal Ag(I)-Sb(III)-metallotherapeutics of the NSAIDs, aspirin and salicylic acid: Enhancement of their solubility and bioactivity by using the surfactant CTAB.

    PubMed

    Gkaniatsou, E I; Banti, C N; Kourkoumelis, N; Skoulika, S; Manoli, M; Tasiopoulos, A J; Hadjikakou, S K

    2015-09-01

    The already known Ag(I)-Sb(III) compound of the formula {Ag(Ph3Sb)3(NO3)} (1) and two novel mixed metal Ag(I)-Sb(III) metallotherapeutics of the formulae {Ag(Ph3Sb)3(SalH)}(2) and {Ag(Ph3Sb)3(Asp)}(3) (SalH2=salicylic acid, AspH=aspirin or 2-acetylsalicylic acid and Ph3Sb=triphenyl antimony(III)) have been synthesised and characterised by m.p., vibrational spectroscopy (mid-FT-IR), (13)C-,(1)H-NMR, UV-visible (UV-vis) spectroscopic techniques, high resolution mass spectroscopy (HRMS) and X-ray crystallography. Compounds 1,-3 were treated with the surfactant cetyltrimethylammonium bromide (CTAB) in order to enhance their solubility and as a consequence their bioactivity. The resulting micelles a-c were characterised with X-ray powder diffraction (XRPD) analysis, X-ray fluorescence (XRF) spectroscopy, Energy-dispersive X-ray spectroscopy (EDX), conductivity, Thermal gravimetry-differential thermal analysis (TG-DTA), and atomic absorption. Compounds 1-3 and the relevant micelles a-c were evaluated for their in vitro cytotoxic activity against human cancer cell lines: MCF-7 (breast, estrogen receptor (ER) positive), MDA-MB-231 (breast, ER negative) and MRC-5 (normal human fetal lung fibroblast cells) with sulforhodamine B (SRB) colorimetric assay. The results show significant increase in the activity of micelles compared to that of the initial compounds. Moreover, micelles exhibited lower activity against normal cells than tumor cells. The binding affinity of a-c towards the calf thymus (CT)-DNA, lipoxygenase (LOX) and glutathione (GSH) was studied by the fluorescent emission light and UV-vis spectroscopy.

  5. Rational Design of Emissive NIR-Absorbing Chromophores: Rh(III) Porphyrin-Aza-BODIPY Conjugates with Orthogonal Metal-Carbon Bonds.

    PubMed

    Zhou, Jinfeng; Gai, Lizhi; Zhou, Zhikuan; Yang, Wu; Mack, John; Xu, Kejing; Zhao, Jianzhang; Zhao, Yue; Qiu, Hailin; Chan, Kin Shing; Shen, Zhen

    2016-09-01

    The facile synthesis of Group 9 Rh(III) porphyrin-aza-BODIPY conjugates that are linked through an orthogonal Rh-C(aryl) bond is reported. The conjugates combine the advantages of the near-IR (NIR) absorption and intense fluorescence of aza-BODIPY dyes with the long-lived triplet states of transition metal rhodium porphyrins. Only one emission peak centered at about 720 nm is observed, irrespective of the excitation wavelength, demonstrating that the conjugates act as unique molecules rather than as dyads. The generation of a locally excited (LE) state with intramolecular charge-transfer (ICT) character has been demonstrated by solvatochromic effects in the photophysical properties, singlet oxygen quantum yields in polar solvents, and by the results of density functional theory (DFT) calculations. In nonpolar solvents, the Rh(III) conjugates exhibit strong aza-BODIPY-centered fluorescence at around 720 nm (ΦF =17-34 %), and negligible singlet oxygen generation. In polar solvents, enhancements of the singlet-oxygen quantum yield (ΦΔ =19-27 %, λex =690 nm) have been observed. Nanosecond pulsed time-resolved absorption spectroscopy confirms that relatively long-lived triplet excited states are formed. The synthetic methodology outlined herein provides a useful strategy for the assembly of functional materials that are highly desirable for a wide range of applications in material science and biomedical fields. PMID:27516405

  6. Rational Design of Emissive NIR-Absorbing Chromophores: Rh(III) Porphyrin-Aza-BODIPY Conjugates with Orthogonal Metal-Carbon Bonds.

    PubMed

    Zhou, Jinfeng; Gai, Lizhi; Zhou, Zhikuan; Yang, Wu; Mack, John; Xu, Kejing; Zhao, Jianzhang; Zhao, Yue; Qiu, Hailin; Chan, Kin Shing; Shen, Zhen

    2016-09-01

    The facile synthesis of Group 9 Rh(III) porphyrin-aza-BODIPY conjugates that are linked through an orthogonal Rh-C(aryl) bond is reported. The conjugates combine the advantages of the near-IR (NIR) absorption and intense fluorescence of aza-BODIPY dyes with the long-lived triplet states of transition metal rhodium porphyrins. Only one emission peak centered at about 720 nm is observed, irrespective of the excitation wavelength, demonstrating that the conjugates act as unique molecules rather than as dyads. The generation of a locally excited (LE) state with intramolecular charge-transfer (ICT) character has been demonstrated by solvatochromic effects in the photophysical properties, singlet oxygen quantum yields in polar solvents, and by the results of density functional theory (DFT) calculations. In nonpolar solvents, the Rh(III) conjugates exhibit strong aza-BODIPY-centered fluorescence at around 720 nm (ΦF =17-34 %), and negligible singlet oxygen generation. In polar solvents, enhancements of the singlet-oxygen quantum yield (ΦΔ =19-27 %, λex =690 nm) have been observed. Nanosecond pulsed time-resolved absorption spectroscopy confirms that relatively long-lived triplet excited states are formed. The synthetic methodology outlined herein provides a useful strategy for the assembly of functional materials that are highly desirable for a wide range of applications in material science and biomedical fields.

  7. Advanced Computational and Experimental Techniques for Nacelle Liner Performance Evaluation

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Jones, Michael G.; Brown, Martha C.; Nark, Douglas

    2009-01-01

    The Curved Duct Test Rig (CDTR) has been developed to investigate sound propagation through a duct of size comparable to the aft bypass duct of typical aircraft engines. The axial dimension of the bypass duct is often curved and this geometric characteristic is captured in the CDTR. The semiannular bypass duct is simulated by a rectangular test section in which the height corresponds to the circumferential dimension and the width corresponds to the radial dimension. The liner samples are perforate over honeycomb core and are installed on the side walls of the test section. The top and bottom surfaces of the test section are acoustically rigid to simulate a hard wall bifurcation or pylon. A unique feature of the CDTR is the control system that generates sound incident on the liner test section in specific modes. Uniform air flow, at ambient temperature and flow speed Mach 0.275, is introduced through the duct. Experiments to investigate configuration effects such as curvature along the flow path on the acoustic performance of a sample liner are performed in the CDTR and reported in this paper. Combinations of treated and acoustically rigid side walls are investigated. The scattering of modes of the incident wave, both by the curvature and by the asymmetry of wall treatment, is demonstrated in the experimental results. The effect that mode scattering has on total acoustic effectiveness of the liner treatment is also shown. Comparisons of measured liner attenuation with numerical results predicted by an analytic model based on the parabolic approximation to the convected Helmholtz equation are reported. The spectra of attenuation produced by the analytic model are similar to experimental results for both walls treated, straight and curved flow path, with plane wave and higher order modes incident. The numerical model is used to define the optimized resistance and reactance of a liner that significantly improves liner attenuation in the frequency range 1900-2400 Hz. A

  8. Nonlinear Color-Metallicity Relations of Globular Clusters. III. On the Discrepancy in Metallicity between Globular Cluster Systems and Their Parent Elliptical Galaxies

    NASA Astrophysics Data System (ADS)

    Yoon, Suk-Jin; Lee, Sang-Yoon; Blakeslee, John P.; Peng, Eric W.; Sohn, Sangmo T.; Cho, Jaeil; Kim, Hak-Sub; Chung, Chul; Kim, Sooyoung; Lee, Young-Wook

    2011-12-01

    One of the conundrums in extragalactic astronomy is the discrepancy in observed metallicity distribution functions (MDFs) between the two prime stellar components of early-type galaxies—globular clusters (GCs) and halo field stars. This is generally taken as evidence of highly decoupled evolutionary histories between GC systems and their parent galaxies. Here we show, however, that new developments in linking the observed GC colors to their intrinsic metallicities suggest nonlinear color-to-metallicity conversions, which translate observed color distributions into strongly peaked, unimodal MDFs with broad metal-poor tails. Remarkably, the inferred GC MDFs are similar to the MDFs of resolved field stars in nearby elliptical galaxies and those produced by chemical evolution models of galaxies. The GC MDF shape, characterized by a sharp peak with a metal-poor tail, indicates a virtually continuous chemical enrichment with a relatively short timescale. The characteristic shape emerges across three orders of magnitude in the host galaxy mass, suggesting a universal process of chemical enrichment among various GC systems. Given that GCs are bluer than field stars within the same galaxy, it is plausible that the chemical enrichment processes of GCs ceased somewhat earlier than that of the field stellar population, and if so, GCs preferentially trace the major, vigorous mode of star formation events in galactic formation. We further suggest a possible systematic age difference among GC systems, in that the GC systems in more luminous galaxies are older. This is consistent with the downsizing paradigm whereby stars of brighter galaxies, on average, formed earlier than those of dimmer galaxies; this additionally supports the similar nature shared by GCs and field stars. Although the sample used in this study (the Hubble Space Telescope Advanced Camera for Surveys/Wide Field Channel, WFPC2, and WFC3 photometry for the GC systems in the Virgo galaxy cluster) confines our

  9. Analyses of a Reinforced Concrete Containment with Liner Corrosion Damage

    SciTech Connect

    Cherry, J.L.; Smith, J.A.

    1998-11-19

    Incidents of liner corrosion in nuclear power containment structures have been recorded. These incidents and concerns of other possible liner corrosion in containment have prompted an interest in determining g the capacity of a degraded containment. Finite element analyses of a typical pressurized water reactor (PWR) reinforced concrete containment with liner corrosion were conducted using the A13AQUS finite element code with the ANACAP-U nonlinear concrete constitutive model. The effect of liner corrosion on containment capacity was investigated. A loss of coolant accident was simulated by applying pressure and temperature changes to the structure without corrosion to determine baseline failure limits, followed by multiple analyses of the containment with corrosion at different locations and varying degrees of liner degradation. The corrosion locations were chosen at the base of the containment wall, near the equipment hatch, and at the midheight of the containment wall. Using a strain-based failure criterion the different scenarios were evaluated to prioritize their effect on containment capacity

  10. Hydrodynamic Modeling of the Plasma Liner Experiment (PLX)

    NASA Astrophysics Data System (ADS)

    Cassibry, Jason; Hsu, Scott; Witherspoon, Doug; Gilmore, Marc

    2009-11-01

    Implosions of plasma liners in cylindrically or spherically convergent geometries can produce high pressures and temperatures with a confinement or dwell time of the order of the rarefaction timescale of the liner. The Plasma Liner Experiment (PLX), to be built at LANL, will explore and demonstrate the feasibility of forming imploding plasma liners with the spherical convergence of hypersonic plasma jets. Modeling will be performed using SPHC and MACH2. According to preliminary 3D SPHC results, high Z plasma liners imploding on vacuum with ˜1.5MJ of initial stored energy will reach ˜100kbar, which is a main objective of the experimental program. Among the objectives of the theoretical PLX effort are to assist in the diagnostic analysis of the PLX, identify possible deleterious effects due to instabilities or asymmetries, identify departures from ideal behavior due to thermal and radiative transport, and help determine scaling laws for possible follow-on applications of ˜1 Mbar HEDP plasmas and magneto-inertial fusion. An overview of the plan to accomplish these objectives will be presented, and preliminary results will be summarized.

  11. Non-contact optical three dimensional liner metrology.

    SciTech Connect

    Sebring, R. J.; Anderson, W. E.; Bartos, J. J.; Garcia, F.; Randolph, B.; Salazar, M. A.; Edwards, J. M.

    2001-01-01

    We optically captured the 'as-built' liner geometry of NTLX (near term liner experiments) for Shiva Star using ultra-precision ranging lasers. We subsequently verified the resulting digitized geometry against the 3D CAD model of the part. The results confirmed that the Liner contours are within designed tolerances but revealed subtle fabrication artifacts that would typically go undetected. These features included centimeters long waviness and saddle and bulge regions of 1 micron or less in magnitude. The laser technology typically provided 10 micron spatial resolution with {+-}12 nanometer ranging precision. Atlas liners in the future may have to be diamond turned and will have the centimeter wavelength and 100 angstrom amplitude requirements. The advantages of using laser technology are (1) it avoids surface damage that may occur with conventional contact probes and (2) dramatically improves spatial resolution over CMM, capacitance and inductance type probes. Our work is the result of a perceived future need to develop precision, non-contact, liner inspection techniques to verify geometry, characterize machining artifacts and map wall thickness on delicate diamond turned surfaces. Capturing 'as-built' geometry in a non-contact way coupled with part-to-CAD verification software tools creates a new metrology competency for MST-7.

  12. Overview, Status, and Plans of the Plasma Liner Experiment (PLX)

    NASA Astrophysics Data System (ADS)

    Hsu, S. C.; Awe, T. J.; Hanna, D. S.; Davis, J. S.; Witherspoon, F. D.; Cassibry, J. T.; Gilmore, M. A.; Hwang, D. Q.

    2010-11-01

    The Plasma Liner Experiment (PLX) is a multi-institutional collaboration that is exploring and demonstrating the feasibility of forming imploding spherical plasma liners to reach peak pressures ˜0.1 Mbar upon stagnation. The liners will be formed via merging of 30--60 dense high Mach number plasma jets (n˜10^17 cm-3, M˜10--35, v˜50--70 km/s, rjet˜5 cm) in spherically convergent geometry. We are aiming for two potential follow-on applications if this work is successful: (1) assembling repetitive, macroscopic (cm and μs scale) plasmas suitable for fundamental HEDLP scientific studies and (2) a standoff driver solution for magneto-inertial fusion. This is a staged project where scientific issues will be studied first at modest stored energies (˜300 kJ) before attempting to reach HED-relevant pressures (requiring ˜1.5 MJ)@. This poster provides an overview/status of the project and the research plan, which includes numerical/theoretical and experimental studies of plasma jet formation/acceleration, propagation/merging, liner convergence/stagnation, and laser driven beat waves for magnetizing the imploding liner.

  13. Boundary layer effects on liners for aircraft engines

    NASA Astrophysics Data System (ADS)

    Gabard, Gwénaël

    2016-10-01

    The performance of acoustic treatments installed on aircraft engines is strongly influenced by the boundary layer of the grazing flow on the surface of the liner. The parametric study presented in this paper illustrates the extent of this effect and identifies when it is significant. The acoustic modes of a circular duct with flow are calculated using a finite difference method. The parameters are representative of the flow conditions, liners and sound fields found in current turbofan engines. Both the intake and bypass ducts are considered. Results show that there is a complex interplay between the boundary layer thickness, the direction of propagation and the liner impedance and that the boundary layer can have a strong impact on liner performance for typical configurations (including changes of the order of 30 dB on the attenuation of modes associated with tonal fan noise). A modified impedance condition including the effect of a small but finite boundary layer thickness is considered and compared to the standard Myers condition based on an infinitely thin boundary layer. We show how this impedance condition can be implemented in a mode calculation method by introducing auxiliary variables. This condition is able to capture the trends associated with the boundary layer effects and in most cases provides improved predictions of liner performance.

  14. Deep SDSS optical spectroscopy of distant halo stars. III. Chemical analysis of extremely metal-poor stars

    NASA Astrophysics Data System (ADS)

    Fernández-Alvar, E.; Allende Prieto, C.; Beers, T. C.; Lee, Y. S.; Masseron, T.; Schneider, D. P.

    2016-09-01

    Aims: We present the results of an analysis of 107 extremely metal-poor (EMP) stars with metallicities lower than [Fe/H] =- 3.0, identified in medium-resolution spectra in the Sloan Digital Sky Survey (SDSS). Our analysis provides estimates of the stellar effective temperatures and surface gravities, as well as iron, calcium, and magnesium abundances. Methods: We followed the same method as in previous papers of this series. The method is based on comparisons of the observed spectra with synthetic spectra. The abundances of Fe, Ca, and Mg were determined by fitting spectral regions that are dominated by lines of each element. In addition, we present a technique to determine upper limits for elements whose features are not detected in a given spectrum. We also analyzed our sample with the SEGUE stellar parameter pipeline to obtain additional determinations of the atmospheric parameters and iron and alpha-element abundances, which we thend compare with ours. In addition, we used these parameters to infer [C/Fe] ratios. Results: Ca is typically the only element in these spectra with a moderate to low signal-to-noise ratio and medium resolution in this metallicity regime with lines that are sufficiently strong to reliably measure its abundance. Fe and Mg exhibit weaker features that in most cases only provide upper limits. We measured [Ca/Fe] and [Mg/Fe] for EMP stars in the SDSS spectra and conclude that most of the stars exhibit the typical enhancement level for α-elements, ~+0.4, although some stars for which only [Fe/H] upper limits could be estimated indicate higher [α/Fe] ratios. We also find that 26% of the stars in our sample can be classified as carbon-enhanced metal-poor (CEMP) stars and that the frequency of CEMP stars also increases with decreasing metallicity, as has been reported for previous samples. We identify a rare, bright (g = 11.90) EMP star, SDSS J134144.61+474128.6, with [Fe/H] =- 3.27, [C/Fe] = + 0.95, and elevated magnesium ([Mg/Fe] =+ 0

  15. Metal-ligand interaction of lanthanides with coumarin derivatives. Part I. Complexation of 3-(1-aminoethylidene)-2H-chromene-2,4(3H)-dione with La(III), Ce(III), Nd(III) and Ho(III).

    PubMed

    Swiatek, Mirosława; Kufelnicki, Aleksander

    2012-01-01

    Solutions of lanthanum(III), cerium(III), neodymium(III) and holmium(III) nitrates with 3-(1-aminoethylidene)-2H-chromene-2,4(3H)-dione (1) in 10% v/v dioxane-water medium were used. Coordination modes of 1 with the selected lanthanides have been examined. Hydroxo-complexes with deprotonated water molecules from the inner coordination sphere have been stated in basic medium. Stability constants of the forming complex species were determined by potentiometric titrations using Superquad and Hyperquad2003 programs. The most stable complexes are formed with La(III). The UV-Vis spectra of the Nd(III)-1 system confirmed the L:M = 1:1 stoichiometry evaluated potentiometrically.

  16. Structural and electronic properties of hetero-transition-metal Keggin anions: a DFT Study of alpha/beta-[XW12O40]n- (X = CrVI, VV, TiIV, FeIII, CoIII, NiIII, CoII, and ZnII) relative stability.

    PubMed

    Zhang, Fu-Qiang; Zhang, Xian-Ming; Wu, Hai-Shun; Jiao, Haijun

    2007-01-11

    Density functional theory calculations have been carried out to investigate the electronic structures and the alpha/beta relative stability of Keggin-typed [XW(12)O(40)]n- anions with transition metal as heteroatom X (X = Cr(VI), V(V), Ti(IV), Fe(III), Co(III), Ni(III), Co(II) and Zn(II)). Nice agreement in geometries between computation and experiment has been obtained, and the higher stability of the alpha isomer over the beta one has been confirmed. Structural parameter analysis reveals that the {M(3)O(13)} triads in both alpha and beta isomers contract considerably with the increase of the negative anionic charge, while the overall size of both isomers shrinks only slightly. Fragment molecular orbital analysis shows that except alpha/beta-[TiW(12)O(40)]4-, the electronic structures of Keggin anions can be described by the insertion of the e and/or t2 orbital of XO4n- into the frontier orbitals of W(12)O(36) cage, and this leads to the specific redox property, which is different from that of the Keggin anions with main-group elements as heteroatoms. Energy decomposition analysis shows that the enhanced intrinsic stability of the alpha isomer in Td arrangement of W(12)O(36) shell and the larger deformation of the alpha over the beta isomer are two dominating factors and contribute oppositely to the alpha/beta relative stability. PMID:17201398

  17. Making a Metal-Lined Composite-Overwrapped Pressure Vessel

    NASA Technical Reports Server (NTRS)

    DeLay, Tom

    2005-01-01

    process has been devised for the fabrication of a pressure vessel that comprises a composite-material (matrix/fiber) shell with a metal liner on its inner surface. The use of the composite material makes it possible for the tank to be strong enough to withstand the anticipated operating pressure and yet weigh less than does an equivalent all-metal tank. The metal liner is used as a barrier against permeation: In the absence of such a barrier, the pressurized gas in the tank could leak by diffusing through the composite-material shell. The figure depicts workpieces at four key stages in the process, which consists of the following steps: 1. A mandrel that defines the size and shape of the pressure vessel is made by either molding or machining a piece of tooling wax. 2. Silver paint is applied to the surface of the mandrel to make it electrically conductive. 3. The ends of the mandrel are fitted with metal bosses. 4. The mandrel is put into a plating bath, wherein the metal liner is electrodeposited. Depending on the applications, the liner metal could be copper, nickel, gold, or an alloy. Typical liner thicknesses range from 1 to 10 mils (0.025 to 0.25 mm). 5. The wax is melted from within, leaving the thin metal liner. 6. A hollow shaft that includes holes and fittings through which the liner can be pressurized is sealed to both ends of the liner. The liner is pressurized to stiffen (and hence stabilize) it for the next step. 7. The pressurized liner is placed in a filament-winding machine, which is then operated to cover the liner with multiple layers of an uncured graphite-fiber/epoxy-matrix or other suitable composite material. 8. The composite-overwrapped liner is cured in an oven. 9. The pressure is relieved and the shaft is removed. The tank is then ready for use. The process as described above accommodates variations: a) The mandrel could be made of a wax that melts at a higher temperature and not removed until the tank is cured in the oven. b) The tank need

  18. Migration and Growth of Protoplanetary Embryos. III. Mass and Metallicity Dependence for FGKM Main-sequence Stars

    NASA Astrophysics Data System (ADS)

    Liu, Beibei; Zhang, Xiaojia; Lin, Douglas N. C.

    2016-06-01

    Radial velocity and transit surveys have found that the fraction of FGKM stars with close-in super-Earth(s) (η ⊕) is around 30%–50%, independent of the stellar mass M * and metallicity Z *. In contrast, the fraction of solar-type stars harboring one or more gas giants (η J) with masses M p > 100 M ⊕ is nearly 10%–15%, and it appears to increase with both M * and Z *. Regardless of the properties of their host stars, the total mass of some multiple super-Earths systems exceeds the core mass of Jupiter and Saturn. We suggest that both super-Earths and supercritical cores of gas giants were assembled from a population of embryos that underwent convergent type I migration from their birthplaces to a transition location between viscously heated and irradiation-heated disk regions. We attribute the cause for the η ⊕–η J dichotomy to conditions required for embryos to merge and to acquire supercritical core mass ({M}{{c}}˜ 10 {M}\\oplus ) for the onset of efficient gaseous envelope accretion. We translate this condition into a critical disk accretion rate, and our analysis and simulation results show that it weakly depends on M * and decreases with metallicity of disk gas Z d. We find that embryos are more likely to merge into supercritical cores around relatively massive and metal-rich stars. This dependence accounts for the observed η J–M *. We also consider the {Z}{{d}}{--}{Z}* dispersed relationship and reproduce the observed η J–Z * correlation.

  19. Star formation in the first galaxies - III. Formation, evolution, and characteristics of the first metal-enriched stellar cluster

    NASA Astrophysics Data System (ADS)

    Safranek-Shrader, Chalence; Montgomery, Michael H.; Milosavljević, Miloš; Bromm, Volker

    2016-01-01

    We simulate the formation of a low-metallicity (10-2 Z⊙) stellar cluster at redshift z ˜ 14. Beginning with cosmological initial conditions, the simulation utilizes adaptive mesh refinement and sink particles to follow the collapse and evolution of gas past the opacity limit for fragmentation, thus resolving the formation of individual protostellar cores. A time- and location-dependent protostellar radiation field, which heats the gas by absorption on dust, is computed by integration of protostellar evolutionary tracks. The simulation also includes a robust non-equilibrium chemical network that self-consistently treats gas thermodynamics and dust-gas coupling. The system is evolved for 18 kyr after the first protostellar source has formed. In this time span, 30 sink particles representing protostellar cores form with a total mass of 81 M⊙. Their masses range from ˜0.1 to 14.4 M⊙ with a median mass ˜0.5-1 M⊙. Massive protostars grow by competitive accretion while lower mass protostars are stunted in growth by close encounters and many-body ejections. In the regime explored here, the characteristic mass scale is determined by the cosmic microwave background temperature floor and the onset of efficient dust-gas coupling. It seems unlikely that host galaxies of the first bursts of metal-enriched star formation will be detectable with the James Webb Space Telescope or other next-generation infrared observatories. Instead, the most promising access route to the dawn of cosmic star formation may lie in the scrutiny of metal-poor, ancient stellar populations in the Galactic neighbourhood. The observable targets corresponding to the system simulated here are ultra-faint dwarf satellite galaxies such as Boötes II and Willman I.

  20. Migration and Growth of Protoplanetary Embryos. III. Mass and Metallicity Dependence for FGKM Main-sequence Stars

    NASA Astrophysics Data System (ADS)

    Liu, Beibei; Zhang, Xiaojia; Lin, Douglas N. C.

    2016-06-01

    Radial velocity and transit surveys have found that the fraction of FGKM stars with close-in super-Earth(s) (η ⊕) is around 30%-50%, independent of the stellar mass M * and metallicity Z *. In contrast, the fraction of solar-type stars harboring one or more gas giants (η J) with masses M p > 100 M ⊕ is nearly 10%-15%, and it appears to increase with both M * and Z *. Regardless of the properties of their host stars, the total mass of some multiple super-Earths systems exceeds the core mass of Jupiter and Saturn. We suggest that both super-Earths and supercritical cores of gas giants were assembled from a population of embryos that underwent convergent type I migration from their birthplaces to a transition location between viscously heated and irradiation-heated disk regions. We attribute the cause for the η ⊕-η J dichotomy to conditions required for embryos to merge and to acquire supercritical core mass ({M}{{c}}˜ 10 {M}\\oplus ) for the onset of efficient gaseous envelope accretion. We translate this condition into a critical disk accretion rate, and our analysis and simulation results show that it weakly depends on M * and decreases with metallicity of disk gas Z d. We find that embryos are more likely to merge into supercritical cores around relatively massive and metal-rich stars. This dependence accounts for the observed η J-M *. We also consider the {Z}{{d}}{--}{Z}* dispersed relationship and reproduce the observed η J-Z * correlation.

  1. Modeling, measuring, and mitigating instability growth in liner implosions on Z

    NASA Astrophysics Data System (ADS)

    Peterson, Kyle

    2015-11-01

    Electro-thermal instabilities result from non-uniform heating due to temperature dependence in the conductivity of a material. In this talk, we will discuss the role of electro-thermal instabilities on the dynamics of magnetically accelerated implosion systems. We present simulations that show electro-thermal instabilities form immediately after the surface material of a conductor melts and can act as a significant seed to subsequent magneto-Rayleigh-Taylor (MRT) instability growth. We discuss measurement results from experiments performed on Sandia National Laboratories Z accelerator to investigate signatures of electro-thermal instability growth on well-characterized initially solid aluminum or beryllium rods driven with a 20 MA, 100 ns risetime current pulse. These measurements show good agreement with electro-thermal instability simulations and exhibit larger instability growth than can be explained by MRT theory alone. Recent experiments have confirmed simulation predictions of dramatically reduced instability growth in solid metallic rods when thick dielectric coatings are used to mitigate density perturbations arising from the electro-thermal instability. These results provide further evidence that the inherent surface roughness of the target is not the dominant seed for the MRT instability, in contrast with most inertial confinement fusion approaches. These results suggest a new technique for substantially reducing the integral MRT growth in magnetically driven implosions. Indeed, recent results on the Z facility with 100 km/s Al and Be liner implosions show substantially reduced growth. These new results include axially magnetized, CH-coated beryllium liner radiographs in which the inner liner surface is observed to be remarkably straight and uniform at a radius of about 120 microns (convergence ratio ~20). Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under

  2. Impact of Iron-Reducing Bacteria on Metals and Radionuclides Adsorbed to Humic-Coated Iron(III) Oxides

    SciTech Connect

    Burgos, W. D.

    2005-02-01

    This is the final report for Grant No. DEFGO2-98ER62691 submitted to the DOE NABR Program. This research has focused on (1) the role of natural organic matter (NOM), quinines, and complexants in enhancing the biological reduction of solid-phase crystalline ferric oxides, (2) the effect of heavy metals (specifically zinc) and NOM on ferric oxide bioreduction, (3) the sorption of Me(II) [Cu(II), Fe(II), Mn(II) and Zn(II)] to ferric oxides and subsequent Me(II)-promoted phase transformations of the ferric oxides, and (4) the development of reaction-based biogeochemical models to numerically simulate our experimental results.

  3. In-situ studies on the performance of landfill caps (compacted soil liners, geomembranes, geosynthetic clay liners, capillary barriers)

    SciTech Connect

    Melchior, S.

    1997-12-31

    Since 1986 different types of landfill covers have been studied in-situ on the Georgswerder landfill in Hamburg, Germany. Water balance data are available for eight years. The performance of different carriers has been measured by collecting the leakage on areas ranging from 100 m{sup 2} to 500 m{sup 2}. Composite liners with geomembranes performed best, showing no leakage. An extended capillary barrier also performed well. The performance of compacted soil liners, however, decreased severely within five years due to desiccation, shrinkage and plant root penetration (liner leakage now ranging from 150 mm/a to 200 mm/a). About 50 % of the water that reaches the surface of the liner is leaking through it. The maximum leakage rates have increased from 2 x 10{sup -10} m{sup 3} m{sup -2} s{sup -1} to 4 x 10{sup -8} m{sup 3} m{sup -2} s{sup -1}. Two types of geosynthetic clay liners (GCL) have been tested for two years now with disappointing results. The GCL desiccated during the first dry summer of the study. High percolation rates through the GCL were measured during the following winter (45 mm resp. 63 mm in four months). Wetting of the GCL did not significantly reduce the percolation rates.

  4. Microbial Mineral Transformations at the Fe(II)/Fe(III) Redox Boundary for Solid Phase Capture of Strontium and Other Metal/Radionuclide Contaminants

    SciTech Connect

    F. G. Ferris; E. E. Roden

    2000-01-31

    The migration of {sup 90}Sr in groundwater is a significant environmental concern at former nuclear weapons production sites in the US and abroad. Although retardation of {sup 90}Sr transport relative to mean groundwater velocity is known to occur in contaminated aquifers, Sr{sup 2+} does not sorb as strongly to iron oxides and other mineral phases as do other metal-radionuclides contaminants. Thus, some potential exists for extensive {sup 90}Sr migration from sources of contamination. Chemical or biological processes capable of retarding or immobilizing Sr{sup 2+} in groundwater environments are of interest from the standpoint of understanding controls on subsurface Sr{sup 2+} migration. In addition, it may be possible to exploit such processes for remediation of subsurface Sr contamination. In this study the authors examined the potential for the solid phase sorption and incorporation of Sr{sup 2+} into carbonate minerals formed during microbial Fe(III) oxide reduction as a first step toward evaluating whether this process could be used to promote retardation of {sup 90}Sr migrations in anaerobic subsurface environments. The demonstration of Sr{sup 2+} capture in carbonate mineral phases formed during bacterial HFO reduction and urea hydrolysis suggests that microbial carbonate mineral formation could contribute to Sr{sup 2+} retardation in groundwater environments. This process may also provide a mechanism for subsurface remediation of Sr{sup 2+} and other divalent metal contaminants that form insoluble carbonate precipitates.

  5. Acoustic Liner Drag: Measurements on Novel Facesheet Perforate Geometries

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.; Jones, Michael G.

    2016-01-01

    Interest in characterization of the aerodynamic drag of acoustic liners has increased in the past several years. This paper details experiments in the NASA Langley Grazing Flow Impedance Tube to quantify the relative drag of several perforate-over-honeycomb liner configurations at flow speeds of centerline flow Mach number equals 0.3 and 0.5. Various perforate geometries and orientations are investigated to determine their resistance factors using a static pressure drop approach. Comparison of these resistance factors gives a relative measurement of liner drag. For these same flow conditions, acoustic measurements are performed with tonal excitation from 400 to 3000 hertz at source sound pressure levels of 140 and 150 decibels. Educed impedance and attenuation spectra are used to determine the impact of variations in perforate geometry on acoustic performance.

  6. Progress In Magnetized Target Fusion Driven by Plasma Liners

    NASA Technical Reports Server (NTRS)

    Thio, Francis Y. C.; Kirkpatrick, Ronald C.; Knapp, Charles E.; Cassibry, Jason; Eskridge, Richard; Lee, Michael; Smith, James; Martin, Adam; Wu, S. T.; Schmidt, George; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Magnetized target fusion (MTF) attempts to combine the favorable attributes of magnetic confinement fusion (MCF) for energy confinement with the attributes of inertial confinement fusion (ICF) for efficient compression heating and wall-free containment of the fusing plasma. It uses a material liner to compress and contain a magnetized plasma. For practical applications, standoff drivers to deliver the imploding momentum flux to the target plasma remotely are required. Spherically converging plasma jets have been proposed as standoff drivers for this purpose. The concept involves the dynamic formation of a spherical plasma liner by the merging of plasma jets, and the use of the liner so formed to compress a spheromak or a field reversed configuration (FRC).

  7. Color stability of long-term soft denture liners.

    PubMed

    Shotwell, J L; Razzoog, M E; Koran, A

    1992-11-01

    The use of resilient denture liners in complete denture construction has become increasingly popular for providing comfort for denture wearers. The primary disadvantage of these materials is that the physical and mechanical properties change rapidly with time in a service environment. The purpose of this study is to evaluate the color stability of five commercially available soft denture liners as a function of accelerated aging. Color measurements were made before aging with a colorimeter and data processor. The samples were then weathered for 100 hours in an accelerated aging chamber in the presence of a xenon ultraviolet visible-light source, an intermittent water spray at 110 degrees F, and 90% humidity. After aging, color measurements were made again and color differences (delta E) were calculated. Results were statistically tested with analysis of variance and Scheffé intervals were calculated at 0.96. It was concluded that accelerated aging can be used to evaluate color stability of soft denture liners.

  8. Fracture control method for composite tanks with load sharing liners

    NASA Technical Reports Server (NTRS)

    Bixler, W. D.

    1975-01-01

    The experimental program was based on the premise that the plastic sizing cycle, which each pressure vessel is subjected to prior to operation, acts as an effective proof test of the liner, screening out all flaws or cracks larger than a critical size. In doing so, flaw growth potential is available for cyclic operation at pressures less than the sizing pressure. Static fracture and cyclic life tests, involving laboratory type specimens and filament overwrapped tanks, were conducted on three liner materials: (1) 2219-T62 aluminum, (2) Inconel X750 STA, and (3) cryoformed 301 stainless steel. Variables included material condition, thickness, flaw size, flaw shape, temperature, sizing stress level, operating stress level and minimum-to-maximum operating stress ratio. From the empirical data base obtained, a procedure was established by which the service life of composite tanks with load sharing liners could be guaranteed with a high degree of confidence.

  9. Cast adrift: Gortex cast liners allow greater patient activity.

    PubMed

    Dubowitz, Gerald; Miller, Deborah M

    2003-01-01

    Extremity fractures are a common injury, with nearly 1.5 million cases reported in the United States in 1998. Treatment often involves lengthy periods of immobilization. This report outlines the use of a Gortex cast liner by a subject who was able to engage in swimming and scuba diving during the healing process. We report that a Gortex cast liner may be considered for an active patient who is keen to return to limited activities during fracture healing. Apparently because of a lack of knowledge of their existence, physicians currently are underutilizing this method of casting in active patients. The use of Gortex liners elsewhere has been reported to have higher patient and physician satisfaction in both use and performance, with no reported detrimental effects on outcome.

  10. Optimization of a Ranchero driven high energy liner driver system

    SciTech Connect

    Atchison, Walter L; Kaul, Ann; Rousculp, Chris L; Watt, Robert G

    2008-01-01

    An experimental series is planned to implode a dense heavy liner to a velocity in excess of 1 cm/microsecond (10 mm/microsecond) using a RANCHERO coaxial explosive flux compression generator. The goal of this study is to choose the liner mass and starting radius that will deliver the greatest amount of kinetic energy to a target at 1 cm final radius. In this study we used the 1D-MHD simulation code RA YEN to search for the proper initial conditions. The results will be used as a starting point for 2-D simulations and preliminary designs for the first experiments planned in the 2009/2010 time frame. The preliminary results indicate that a liner velocity of 1.25 cm/microsecond and a kinetic energy of greater than 4 megajoules may be possible.

  11. Transmissivity evolution through interface of composite liners under applied constraint.

    PubMed

    Diagne, M

    2011-08-01

    In landfill liners, geomembranes have defects that constitute preferential passages of leachate from rainwater percolation. Non-woven geotextiles are widely used in wastelandfills as materials having the functions of protection, separation, filtration and drainage. This study seeks to select geotextiles through an investigation conducted among landfill operators who commonly arise a geotextile in the geomembrane-clay interface to facilitate geomembrane welding and to prevent its puncture by angular materials. It also attempts to find out the influence of geotextile in a decimetric transmissivity cell size under 50 kPa stress and smooth ground surface. The results show that the transmissivity in composite liner interface is almost the same as the one calculated with the European standard EN ISO 12958. Transmissivity depends on the mechanical stress applied to the bottom liner, on the geotextile type in the interface and on the ground surface.

  12. Experimental and Theoretical Investigation of a Series of Novel Dimanganese(III) μ-Hydroxo Bisporphyrins: Magneto-Structural Correlation and Effect of Metal Spin on Porphyrin Core Deformation.

    PubMed

    Sil, Debangsu; Bhowmik, Susovan; Khan, Firoz Shah Tuglak; Rath, Sankar Prasad

    2016-04-01

    The synthesis, structure, and properties of a new family of five ethane-bridged dimanganese(III) μ-hydroxo bisporphyrins with the same core structure but different counteranions are reported here. Additions of 10% Brønsted acids such as HI, HBF4, HSbF6, HPF6, and HClO4 to a dichloromethane solution of the dichloro dimanganese(III) bisporphyrin produces complexes having a remarkably bent μ-hydroxo group with I3(-), BF4(-), SbF6(-), PF6(-), and ClO4(-) as counteranions, respectively. The X-ray structures of all complexes have been determined, which have revealed the presence of two equivalent high-spin manganese(III) centers with equally distorted porphyrin rings in the complexes, in sharp contrast with the case for the diiron(III) μ-hydroxo bisporphyrin analogues. (1)H NMR spectra have shown highly deshielded meso resonances, unlike the case for the diiron(III) analogues, where the meso resonances are highly shielded. The variable-temperature magnetic data have been subjected to a least-squares fit which provides a moderate antiferromagnetic coupling through the hydroxo bridge between two zero-field split Mn(III) centers with coupling constant (J) values ranging from -29.5 to -38.6 cm(-1). Fairly good correlations are observed for J with Mn-O(H) distances and Mn-O(H)-Mn angles for all the complexes except for that having an I3(-) counteranion. DFT calculations support the stabilization of two equivalent high-spin Mn(III) porphyrin cores in the complexes and have also explored the role of metal spin in controlling porphyrin ring deformation. Unlike diiron(III) μ-hydroxo bisporphyrin complexes, the dimanganese(III) analogues do not have easily accessible spin states of the metal attainable by subtle environmental perturbations and, therefore, can only stabilize the high-spin state with a variety of counteranions. PMID:27002790

  13. Globular cluster ages determined from the Oosterhoff period-metallicity effect using oxygen-enhanced isochrones. III

    NASA Astrophysics Data System (ADS)

    Sandage, Allan

    1993-08-01

    The new brighter calibration of absolute luminosities of RR Lyrae stars by about 0.25 mag as a function of metallicity via the Oosterhoff period effect gives a revised age of the Galactic globular cluster system as 14 Gyr when used with the oxygen-enhanced main-sequence termination models of Bergbush and VandenBerg (1992). There is no correlation of cluster age with metallicity. The presence or absence of age differences between any two clusters is neither proof nor disproof of the Eggen-Lynden Bell-Sandage model of the formation of the Galaxy by collapse. If there were different density regimes within the initial density fluctuation that was the protogalaxy, then there has been a hierarchy of collapse times for the various parts of the present Galaxy. The age of the universe is 15 Gyr, based on the age of the Galaxy at 14 Gyr, to which 1 Gyr is added for the gestation time of the galaxies. The ratio of this age to the inverse Hubble constant with H(0) about 45 km/s Mpc, based on a recent concordant determination using supernovae of type Ia, is close to the critical value of 2/3 required if the deceleration is caused by a mean density just equal to that needed for closure. For the first time, these new data give the possibility that Omega = 1 from this timing test.

  14. Analysis of the magnetic coupling in binuclear systems. III. The role of the ligand to metal charge transfer excitations revisited

    NASA Astrophysics Data System (ADS)

    Calzado, Carmen J.; Angeli, Celestino; Taratiel, David; Caballol, Rosa; Malrieu, Jean-Paul

    2009-07-01

    In magnetic coordination compounds and solids the magnetic orbitals are essentially located on metallic centers but present some delocalization tails on adjacent ligands. Mean field variational calculations optimize this mixing and validate a single band modelization of the intersite magnetic exchange. In this approach, due to the Brillouin's theorem, the ligand to metal charge transfer (LMCT) excitations play a minor role. On the other hand the extensive configuration interaction calculations show that the determinants obtained by a single excitation on the top of the LMCT configurations bring an important antiferromagnetic contribution to the magnetic coupling. Perturbative and truncated variational calculations show that contrary to the interpretation given in a previous article [C. J. Calzado et al., J. Chem. Phys. 116, 2728 (2002)] the contribution of these determinants to the magnetic coupling constant is not a second-order one. An analytic development enables one to establish that they contribute at higher order as a correlation induced increase in the LMCT components of the wave function, i.e., of the mixing between the ligand and the magnetic orbitals. This larger delocalization of the magnetic orbitals results in an increase in both the ferro- and antiferromagnetic contributions to the coupling constant.

  15. Analysis of the magnetic coupling in binuclear systems. III. The role of the ligand to metal charge transfer excitations revisited.

    PubMed

    Calzado, Carmen J; Angeli, Celestino; Taratiel, David; Caballol, Rosa; Malrieu, Jean-Paul

    2009-07-28

    In magnetic coordination compounds and solids the magnetic orbitals are essentially located on metallic centers but present some delocalization tails on adjacent ligands. Mean field variational calculations optimize this mixing and validate a single band modelization of the intersite magnetic exchange. In this approach, due to the Brillouin's theorem, the ligand to metal charge transfer (LMCT) excitations play a minor role. On the other hand the extensive configuration interaction calculations show that the determinants obtained by a single excitation on the top of the LMCT configurations bring an important antiferromagnetic contribution to the magnetic coupling. Perturbative and truncated variational calculations show that contrary to the interpretation given in a previous article [C. J. Calzado et al., J. Chem. Phys. 116, 2728 (2002)] the contribution of these determinants to the magnetic coupling constant is not a second-order one. An analytic development enables one to establish that they contribute at higher order as a correlation induced increase in the LMCT components of the wave function, i.e., of the mixing between the ligand and the magnetic orbitals. This larger delocalization of the magnetic orbitals results in an increase in both the ferro- and antiferromagnetic contributions to the coupling constant.

  16. 17O nuclear quadrupole coupling constants of water bound to a metal ion: A gadolinium(III) case study

    NASA Astrophysics Data System (ADS)

    Yazyev, Oleg V.; Helm, Lothar

    2006-08-01

    Rotational correlation times of metal ion aqua complexes can be determined from O17 NMR relaxation rates if the quadrupole coupling constant of the bound water oxygen-17 nucleus is known. The rotational correlation time is an important parameter for the efficiency of Gd3+ complexes as magnetic resonance imaging contrast agents. Using a combination of density functional theory with classical and Car-Parrinello molecular dynamics simulations we performed a computational study of the O17 quadrupole coupling constants in model aqua ions and the [Gd(DOTA)(H2O)]- complex used in clinical diagnostics. For the inner sphere water molecule in the [Gd(DOTA)(H2O)]- complex the determined quadrupole coupling parameter χ√1+η2/3 of 8.7MHz is very similar to that of the liquid water (9.0MHz ). Very close values were also predicted for the the homoleptic aqua ions of Gd3+ and Ca2+. We conclude that the O17 quadrupole coupling parameters of water molecules coordinated to closed shell and lanthanide metal ions are similar to water molecules in the liquid state.

  17. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... pressure-integrity test below that liner shoe, or subsequent liner shoes if set. The District Manager may... a minimum of 500 psi above the formation fracture pressure at the casing shoe into which the...

  18. Optimization of Microphone Locations for Acoustic Liner Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; June, J. C.

    2015-01-01

    Two impedance eduction methods are explored for use with data acquired in the NASA Langley Grazing Flow Impedance Tube. The first is an indirect method based on the convected Helmholtz equation, and the second is a direct method based on the Kumaresan and Tufts algorithm. Synthesized no-flow data, with random jitter to represent measurement error, are used to evaluate a number of possible microphone locations. Statistical approaches are used to evaluate the suitability of each set of microphone locations. Given the computational resources required, small sample statistics are employed for the indirect method. Since the direct method is much less computationally intensive, a Monte Carlo approach is employed to gather its statistics. A comparison of results achieved with full and reduced sets of microphone locations is used to determine which sets of microphone locations are acceptable. For the indirect method, each array that includes microphones in all three regions (upstream and downstream hard wall sections, and liner test section) provides acceptable results, even when as few as eight microphones are employed. The best arrays employ microphones well away from the leading and trailing edges of the liner. The direct method is constrained to use microphones opposite the liner. Although a number of arrays are acceptable, the optimum set employs 14 microphones positioned well away from the leading and trailing edges of the liner. The selected sets of microphone locations are also evaluated with data measured for ceramic tubular and perforate-over-honeycomb liners at three flow conditions (Mach 0.0, 0.3, and 0.5). They compare favorably with results attained using all 53 microphone locations. Although different optimum microphone locations are selected for the two impedance eduction methods, there is significant overlap. Thus, the union of these two microphone arrays is preferred, as it supports usage of both methods. This array contains 3 microphones in the upstream

  19. Constraining the Accretion Mode in LINER 1.9s

    NASA Astrophysics Data System (ADS)

    Sabra, Bassem; Der Sahaguian, Elias; Badr, Elie

    2016-01-01

    The accretion mode and the dominant power source in low-ionization nuclear emission-line regions (LINERs), a class of active galactic nuclei (AGN), are still elusive. We focus on a sample of 22 LINER 1.9s (Ho et al. 1997), a subclass of LINERs that show broad Halpha lines, a signature of blackhole-powered accretion, to test the hypothesis that the ionizing continuum emitted by a radiatively inefficient accretion flow (RIAF) could lead to the LINER ultraviolet (UV) emission-line ratios. Optical line-ratio diagrams are a weak diagnostic tool in distinguishing between possible power sources (Sabra et al. 2003). We search the Mikulski Archive for Space Telescopes (MAST) for UV spectra of the objects in the above sample and also perform photoionization simulations using CLOUDY (Ferland et al. 2013). Unfortunately, only one object (NGC 1052; Gabel et al. 2000) of the 22 LINER 1.9s has UV spectra that cover many emission lines; the rest of the objects either do not have any UV spectra, the spectral coverage is in-adequate, or the spectra have very low signal-to-noise ratios. Our photoionization simulations set up two identical grids of clouds with a range of densities and ionization parameters. We illuminate one grid with radiation emitted by a thin accretion disk (AD) and we illuminate the other grid with radiation from a RIAF. We overplot the UV emission-line ratio predictions for AD and RIAF illumination, together with the available line ratios for NGC 1052. Initial results show that UV lines could be used as diagnostics for the accretion mode in AGN. More UV spectral coverage of LINER 1.9s is needed in order to more fully utilize the diagnostic powers of UV emission line ratios.

  20. Blood levels of the heavy metal, lead, and caries in children aged 24-72 months: NHANES III.

    PubMed

    Wiener, R Constance; Long, D Leann; Jurevic, Richard J

    2015-01-01

    Lead remains a significant pollutant. It has acute toxic and chronic effects on many tissues and accumulates in teeth and bones. The researchers for this study investigated the association of blood lead levels with the extent/severity of caries as measured by the number of decayed/filled teeth of children aged 24-72 months using data from NHANES III (the Third National Health and Nutrition Examination Survey), accounting for the excess zero caries in the analysis and using less than 2 µg/dl as the reference blood lead level (n = 3,127). Zero-inflated negative binomial regression models indicated unadjusted extent/severity mean ratios of 1.79, 1.88 and 1.94 for the number of decayed/filled teeth in children whose blood lead levels were 2-5, 5-10 and >10 µg/dl, respectively, compared with children having <2 µg/dl blood lead levels. The results did not attenuate when other variables were added to the model for the 5-10 and >10 µg/dl levels of exposure. The adjusted extent/severity mean ratios were 1.84, 2.14 and 1.91, respectively, for the categories. This study indicated a strong association of blood lead levels with increasing numbers of carious teeth in children aged 24-72 months. These findings support other studies in an innovative analysis handling cases of children with no caries. The findings may inform caries risk assessment.

  1. Blood levels of the heavy metal, lead, and caries in children aged 24-72 months: NHANES III.

    PubMed

    Wiener, R Constance; Long, D Leann; Jurevic, Richard J

    2015-01-01

    Lead remains a significant pollutant. It has acute toxic and chronic effects on many tissues and accumulates in teeth and bones. The researchers for this study investigated the association of blood lead levels with the extent/severity of caries as measured by the number of decayed/filled teeth of children aged 24-72 months using data from NHANES III (the Third National Health and Nutrition Examination Survey), accounting for the excess zero caries in the analysis and using less than 2 µg/dl as the reference blood lead level (n = 3,127). Zero-inflated negative binomial regression models indicated unadjusted extent/severity mean ratios of 1.79, 1.88 and 1.94 for the number of decayed/filled teeth in children whose blood lead levels were 2-5, 5-10 and >10 µg/dl, respectively, compared with children having <2 µg/dl blood lead levels. The results did not attenuate when other variables were added to the model for the 5-10 and >10 µg/dl levels of exposure. The adjusted extent/severity mean ratios were 1.84, 2.14 and 1.91, respectively, for the categories. This study indicated a strong association of blood lead levels with increasing numbers of carious teeth in children aged 24-72 months. These findings support other studies in an innovative analysis handling cases of children with no caries. The findings may inform caries risk assessment. PMID:25358243

  2. Reaction mechanism of the epsilon subunit of E. coli DNA polymerase III: insights into active site metal coordination and catalytically significant residues.

    PubMed

    Cisneros, G Andrés; Perera, Lalith; Schaaper, Roel M; Pedersen, Lars C; London, Robert E; Pedersen, Lee G; Darden, Thomas A

    2009-02-01

    The 28 kDa epsilon subunit of Escherichia coli DNA polymerase III is the exonucleotidic proofreader responsible for editing polymerase insertion errors. Here, we study the mechanism by which epsilon carries out the exonuclease activity. We performed quantum mechanics/molecular mechanics calculations on the N-terminal domain containing the exonuclease activity. Both the free-epsilon and a complex epsilon bound to a theta homologue (HOT) were studied. For the epsilon-HOT complex Mg(2+) or Mn(2+) were investigated as the essential divalent metal cofactors, while only Mg(2+) was used for free-epsilon. In all calculations a water molecule bound to the catalytic metal acts as the nucleophile for hydrolysis of the phosphate bond. Initially, a direct proton transfer to H162 is observed. Subsequently, the nucleophilic attack takes place followed by a second proton transfer to E14. Our results show that the reaction catalyzed with Mn(2+) is faster than that with Mg(2+), in agreement with experiment. In addition, the epsilon-HOT complex shows a slightly lower energy barrier compared to free-epsilon. In all cases the catalytic metal is observed to be pentacoordinated. Charge and frontier orbital analyses suggest that charge transfer may stabilize the pentacoordination. Energy decomposition analysis to study the contribution of each residue to catalysis suggests that there are several important residues. Among these, H98, D103, D129, and D146 have been implicated in catalysis by mutagenesis studies. Some of these residues were found to be structurally conserved on human TREX1, the exonuclease domains from E. coli DNA-Pol I, and the DNA polymerase of bacteriophage RB69.

  3. Redox-inactive metal ions modulate the reactivity and oxygen release of mononuclear non-haem iron(III)–peroxo complexes

    SciTech Connect

    Bang, Suhee; Lee, Yong -Min; Hong, Seungwoo; Cho, Kyung -Bin; Nishida, Yusuke; Seo, Mi Sook; Sarangi, Ritimukta; Fukuzumi, Shunichi; Nam, Wonwoo

    2014-09-14

    Redox-inactive metal ions that function as Lewis acids play pivotal roles in modulating the reactivity of oxygen-containing metal complexes and metalloenzymes, such as the oxygen-evolving complex in photosystem II and its small-molecule mimics. Here we report the synthesis and characterization of non-haem iron(III)–peroxo complexes that bind redox-inactive metal ions, (TMC)FeIII–(μ,η22-O2)–Mn+ (Mn+ = Sr2+, Ca2+, Zn2+, Lu3+, Y3+ and Sc3+; TMC, 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane). We demonstrate that the Ca2+ and Sr2+ complexes showed similar electrochemical properties and reactivities in one-electron oxidation or reduction reactions. However, the properties and reactivities of complexes formed with stronger Lewis acidities were found to be markedly different. In conclusion, complexes that contain Ca2+ or Sr2+ ions were oxidized by an electron acceptor to release O2, whereas the release of O2 did not occur for complexes that bind stronger Lewis acids. Furthermore, we discuss these results in the light of the functional role of the Ca2+ ion in the oxidation of water to dioxygen by the oxygen-evolving complex.

  4. Fracture Test Methods for Plastically Responding COPV Liners

    NASA Technical Reports Server (NTRS)

    Dawicke, David S.; Lewis, Joseph C.

    2009-01-01

    An experimental procedure for evaluating the validity of using uniaxial tests to provide a conservative bound on the fatigue crack growth rate behavior small cracks in bi-axially loaded Composite Overwrapped Pressure Vessel (COPV) liners is described. The experimental procedure included the use of a laser notch to quickly generate small surface fatigue cracks with the desired size and aspect ratios. An out-of-plane constraint system was designed to allow fully reversed, fully plastic testing of thin sheet uniaxial coupons. Finally, a method was developed to determine to initiate small cracks in the liner of COPVs.

  5. Diagnosing magnetized liner inertial fusion experiments on Z

    SciTech Connect

    Hansen, S. B. Gomez, M. R.; Sefkow, A. B.; Slutz, S. A.; Sinars, D. B.; Hahn, K. D.; Harding, E. C.; Knapp, P. F.; Schmit, P. F.; Awe, T. J.; McBride, R. D.; Jennings, C. A.; Geissel, M.; Harvey-Thompson, A. J.; Peterson, K. J.; Rovang, D. C.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Hess, M. H.; and others

    2015-05-15

    Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (∼10{sup 12} DD neutrons) from multi-keV deuterium plasmas inertially confined by slow (∼10 cm/μs), stable, cylindrical implosions. Effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 10{sup 10}. Analysis of extensive power, imaging, and spectroscopic x-ray measurements provides a detailed picture of ∼3 keV temperatures, 0.3 g/cm{sup 3} densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  6. Novel Processing of 81-mm Cu Shaped Charge Liners

    SciTech Connect

    Schwartz, A; Korzekwa, D

    2002-01-16

    A seven-step procedure was developed for producing shaped charge liner blanks by back extrusion at liquid nitrogen temperatures. Starting with a 38.1-mm diameter, 101.6-mm long cylinder at 77K, three forging steps with a flat-top die are required to produce the solid cone while maintaining low temperature. The solid cone is forged in four individual back extrusions at 77K to produce the rough liner blank. This procedure is capable of being run in batch processes to improve the time efficiency.

  7. Shock-absorbing behavior of four processed soft denture liners.

    PubMed

    Kawano, F; Kon, M; Koran, A; Matsumoto, N

    1994-12-01

    The cushioning effect of soft denture liners was evaluated with the use of a free drop test with an accelerometer. The materials tested included SuperSoft, Kurepeet-Dough, Molteno Soft, and Molloplast-B brands. All materials were found to reduce the impact force when compared with denture base resin. A 2.4 mm layer of soft denture material demonstrated good shock absorption. The Molloplast-B and Molteno Soft materials showed excellent shock absorption. When the soft denture liner was stored in distilled water for 180 days, the damping effect recorded for all materials tested was increased. The aging of all materials also affected the cushioning effect.

  8. Thermal Radiation Brightness in Double Liner and Dynamic Hohlraum

    NASA Astrophysics Data System (ADS)

    Zakharov, S. V.; Novikov, V. G.

    2001-10-01

    In the concept of the magnetically driven Double Liner ^1 and Dynamic Hohlraum ^2, the high intensity thermal X-radiation is generated by strongly radiating shock wave of colliding outer onto inner dens plasma shells (liners). The radiation is partially trapped by the outer liner and due to that radiation field inside may be much more intensive than outside. That trapped radiation may be used to irradiate a target for High Energy Density Physics or Inertial Confinement Fusion research. In this report we propose some ideas to optimize the Double Liner system to enhance trapped radiation brightness in current and future experiments. Our ideas are based on the model ^1 and new level of understanding of physical processes in Double Liner dynamics and radiation behavior in non-LTE heavy ion plasmas. In our model, due to a diffusive and convective (in view of Rayleigh-Taylor instability) penetration of high magnetic field into heavy ion plasma of the outer shell the radiating shock wave is generated in a substance of the inner liner by the compressed magnetic field pressure. The high intensity thermal radiation is produced in the shock wave as result of a chain of processes i.e. light ion component viscosity heating, electron heating in ion-electron elastic collisions, electron excitation of doped multicharged (Z>>1) ions. For this reason and to be optically thin to ensure a penetration of radiation to target from one side and to produce the line X-radiation effectively from the other one the inner shell substance is compounded from light and heavy atoms in certain proportion. The radiation is reabsorbed and thermolized by outer liner plasma shell. To intensify reabsorbing and thermolizing the outer shell has to contain some portion of the same kind of heavy ions like inner one and to consist of mixture of heavy ions with overlapping line wings of different ions and covering the whole substantial spectral band. Brightness for pure tungsten outer shell and optimal

  9. Diagnosing magnetized liner inertial fusion experiments on Z

    DOE PAGES

    Hansen, Stephanie B.; Gomez, Matthew R.; Sefkow, Adam B.; Slutz, Stephen A.; Sinars, Daniel Brian; Hahn, Kelly; Harding, Eric; Knapp, Patrick; Schmit, Paul; Awe, Thomas James; et al

    2015-05-14

    The Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (~1012 DD neutrons) from multi-keV deuterium plasmasinertially confined by slow (~10 cm/μs), stable, cylindrical implosions. Moreover, effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 1010. Further analysis of extensive power, imaging, and spectroscopicx-ray measurements provides a detailed picture of ~3 keV temperatures, 0.3 g/cm3 densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  10. Diagnosing magnetized liner inertial fusion experiments on Z

    SciTech Connect

    Hansen, Stephanie B.; Gomez, Matthew R.; Sefkow, Adam B.; Slutz, Stephen A.; Sinars, Daniel Brian; Hahn, Kelly; Harding, Eric; Knapp, Patrick; Schmit, Paul; Awe, Thomas James; McBride, Ryan D.; Jennings, Christopher; Geissel, Matthias; Harvey-Thompson, Adam James; Peterson, K. J.; Rovang, Dean C.; Chandler, Gordon A.; Cooper, Gary Wayne; Cuneo, Michael Edward; Herrmann, Mark C.; Mark Harry Hess; Johns, Owen; Lamppa, Derek C.; Martin, Matthew; Porter, J. L.; Robertson, G. K.; Rochau, G. A.; Ruiz, C. L.; Savage, M. E.; Smith, I. C.; Stygar, W. A.; Vesey, R. A.; Blue, B. E.; Ryutov, D.; Schroen, Diana; Tomlinson, K.

    2015-05-14

    The Magnetized Liner Inertial Fusion experiments performed at Sandia's Z facility have demonstrated significant thermonuclear fusion neutron yields (~1012 DD neutrons) from multi-keV deuterium plasmasinertially confined by slow (~10 cm/μs), stable, cylindrical implosions. Moreover, effective magnetic confinement of charged fusion reactants and products is signaled by high secondary DT neutron yields above 1010. Further analysis of extensive power, imaging, and spectroscopicx-ray measurements provides a detailed picture of ~3 keV temperatures, 0.3 g/cm3 densities, gradients, and mix in the fuel and liner over the 1–2 ns stagnation duration.

  11. The analysis of directionality of honed cylinder liners surfaces.

    PubMed

    Pawlus, P; Reizer, R; Wieczorowski, M

    2014-01-01

    Various methods describing the directionality of honed cylinder liner surface topography are compared. The procedure of deep valleys recognition and determination of angular spectra on the basis of ratio of valleys widths in perpendicular directions is described in detail. The applications of deep valleys analysis, power spectral density, and cross-correlation functions for measured plateau-honed cylinder surface topographies were studied. It was found that method based on the deep valleys study assured correct values of honing angle estimation. Procedure of sampling interval selection for this method application was developed. Usefulness of deep valleys analysis for obtaining parameters characterizing other features specific for cylinder liner surfaces is described. PMID:23784941

  12. Hypervalent iodine(III)-induced oxidative [4+2] annulation of o-phenylenediamines and electron-deficient alkynes: direct synthesis of quinoxalines from alkyne substrates under metal-free conditions.

    PubMed

    Okumura, Sota; Takeda, Youhei; Kiyokawa, Kensuke; Minakata, Satoshi

    2013-10-18

    Hypervalent iodine(III)-induced oxidative [4+2] annulation of o-phenylenediamines and electron-deficient alkynes under metal-free conditions has been developed. The reaction allows for direct access to quinoxalines bearing two electron-withdrawing groups in an efficient manner.

  13. Resolution in electron microscope autoradiography. III. Iodine-125, the effect of heavy metal staining, and a reassessment of critical parameters

    PubMed Central

    1977-01-01

    Resolution for 125I-labeled specimens under electron microscope (EM) autoradiographic conditions was assessed experimentally. With this isotope the size of the silver halide crystal was the most important resolution-limiting factor. Heavy metal staining such as is routinely used in preparing animal tissues for EM autoradiography produced an improvement in resolution of approximately 15-20%. For a 500-1,000-A biological tissue section fixed with OsO4 and stained with uranyl acetate, we obtained resolution (half distance, HD) values of approximately 800 +/- 120 A using Ilford L4 emulsion and 500 +/- 70 A using a Kodak NTE-type emulsion. General aspects of resolution-limiting factors and comparison with 3H and 14C values are discussed. PMID:63463

  14. Some metal complexes of three new potentially heptadentate (N4O3) tripodal Schiff base ligands; synthesis, characterizatin and X-ray crystal structure of a novel eight coordinate Gd(III) complex

    NASA Astrophysics Data System (ADS)

    Golbedaghi, Reza; Moradi, Somaeyh; Salehzadeh, Sadegh; Blackman, Allan G.

    2016-03-01

    The symmetrical and asymmetrical potentially heptadentate (N4O3) tripodal Schiff base ligands (H3L1-H3L3) were synthesized from the condensation reaction of three tripodal tetraamine ligands tpt (trpn), tris (3-aminopropyl) amine; ppe (abap), (2-aminoethyl)bis(3-aminopropyl)amine, and tren, tris(2-aminoethyl)amine, with 5-methoxysalicylaldehyde. Then, the reaction of Ln(III) (Ln = Gd, La and Sm), Al(III), and Fe(III) metal ions with the above ligands was investigated. The resulting compounds were characterized by IR, mass spectrometry and elemental analysis in all cases and NMR spectroscopy in the case of the Schiff base ligands. The X-ray crystal structure of the Gd complex of H3L3 ligand showed that in addition to all donor atoms of the ligand one molecule of H2O is also coordinated to the metal ion and a neutral eight-coordinate complex is formed.

  15. Blood levels of the heavy metal, lead, and caries in children ages 24-72 months: NHANES III

    PubMed Central

    Wiener, RC; Long, DL; Jurevic, RJ

    2014-01-01

    Lead remains a significant pollutant. It has acute toxic and chronic effects on many tissues and accumulates in teeth and bones. The researchers for this study investigated the association of blood lead levels and the extent/severity of caries as measured by the number of decayed/filled teeth of children 24 to72 months using data from the Third National Health and Nutrition Examination Survey (NHANES III) accounting for the excess zero caries in the analysis and using less than 2 μg/dL as the reference blood lead level (N=3127). Zero-inflated negative binomial (ZINB) regression models indicated unadjusted extent/severity mean ratios of 1.79, 1.88, and 1.94 for the number of decayed/filled teeth in children whose blood lead levels were 2-5 μg/dL, 5-10 μg/dL, and >10 μg/dL, respectively when compared with children having less than 2 μg/dL blood lead levels. The results did not attenuate when other variables were added to the model for the 5-10 μg/dL, and >10 μg/dL levels of exposure. The adjusted extent/severity mean ratios were 1.84, 2.14, and 1.91, respectively for the categories. This study indicated a strong association of blood lead levels and increasing numbers of carious teeth in children 24 to72 months. These findings support other studies in an innovative analysis handling cases children with no caries. The findings may inform caries risk assessment. PMID:25358243

  16. Liner Optimization Studies Using the Ducted Fan Noise Prediction Code TBIEM3D

    NASA Technical Reports Server (NTRS)

    Dunn, M. H.; Farassat, F.

    1998-01-01

    In this paper we demonstrate the usefulness of the ducted fan noise prediction code TBIEM3D as a liner optimization design tool. Boundary conditions on the interior duct wall allow for hard walls or a locally reacting liner with axially segmented, circumferentially uniform impedance. Two liner optimization studies are considered in which farfield noise attenuation due to the presence of a liner is maximized by adjusting the liner impedance. In the first example, the dependence of optimal liner impedance on frequency and liner length is examined. Results show that both the optimal impedance and attenuation levels are significantly influenced by liner length and frequency. In the second example, TBIEM3D is used to compare radiated sound pressure levels between optimal and non-optimal liner cases at conditions designed to simulate take-off. It is shown that significant noise reduction is achieved for most of the sound field by selecting the optimal or near optimal liner impedance. Our results also indicate that there is relatively large region of the impedance plane over which optimal or near optimal liner behavior is attainable. This is an important conclusion for the designer since there are variations in liner characteristics due to manufacturing imprecisions.

  17. Effect of liner and porcelain application on zirconia surface structure and composition.

    PubMed

    Alghazzawi, Tariq F; Janowski, Gregg M

    2016-01-01

    The purpose of this study was to determine if there is an effect of liner and porcelain application (layering and pressing techniques) on the surface of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP), which were exposed to permutations of liner, layered porcelain, and pressed porcelain. Scanning electron microscope (SEM)/energy dispersive spectroscope (EDS) was used to identify changes in composition and microstructure after removing liner and porcelain with hydrofluoric acid. Simulated aging was also conducted to determine the effect of liner and porcelain on low-temperature degradation. The control group had a typical equiaxed grain structure, referred to as unaffected. When covered with liner or porcelain, some areas changed in structure and composition and were termed affected. The frequency of affected structure decreased when liner was covered with either layered porcelain or pressed porcelain. There were statistical differences (P<0.05) in the composition between affected and unaffected for zirconium (layered porcelain with liner: affected=60% (0.8%) (m/m), unaffected=69% (4%), layered porcelain without liner: affected=59% (3%), unaffected=65% (3%)) and oxygen (layered porcelain with liner: affected=35% (2%), unaffected=26% (4%), layered porcelain without liner: affected=35% (3%), unaffected=30% (2%)). However, there were statistical differences (P<0.05) in the composition for zirconium and oxygen of the aged layered porcelain without liner only. The liner should not be used before porcelain application, especially when using the layering technique for zirconia restorations. Furthermore, pressing should be considered the technique of choice over layering.

  18. Failure assessment of aluminum liner based filament-wound hybrid riser subjected to internal hydrostatic pressure

    NASA Astrophysics Data System (ADS)

    Dikshit, Vishwesh; Seng, Ong Lin; Maheshwari, Muneesh; Asundi, A.

    2015-03-01

    The present study describes the burst behavior of aluminum liner based prototype filament-wound hybrid riser under internal hydrostatic pressure. The main objective of present study is to developed an internal pressure test rig set-up for filament-wound hybrid riser and investigate the failure modes of filament-wound hybrid riser under internal hydrostatic burst pressure loading. The prototype filament-wound hybrid riser used for burst test consists of an internal aluminum liner and outer composite layer. The carbon-epoxy composites as part of the filament-wound hybrid risers were manufactured with [±55o] lay-up pattern with total composite layer thickness of 1.6 mm using a CNC filament-winding machine. The burst test was monitored by video camera which helps to analyze the failure mechanism of the fractured filament-wound hybrid riser. The Fiber Bragg Grating (FBG) sensor was used to monitor and record the strain changes during burst test of prototype filament-wound hybrid riser. This study shows good improvements in burst strength of filament-wound hybrid riser compared to the monolithic metallic riser. Since, strain measurement using FBG sensors has been testified as a reliable method, we aim to further understand in detail using this technique.

  19. Tribological behavior of plasma spray coatings for marine diesel engine piston ring and cylinder liner

    NASA Astrophysics Data System (ADS)

    Hwang, Jong-Hyun; Han, Myoung-Seoup; Kim, Dae-Young; Youn, Joong-Geun

    2006-06-01

    High-temperature wear characteristics between plasma spray coated piston rings and cylinder liners were investigated to find the optimum combination of coating materials using the disc-on-plate reciprocating wear test in dry conditions. The disc and plate represented the piston ring and the cylinder liner, respectively. Coating materials studied were Cr2O3-NiCr, Cr2O3-NiCr-Mo, and Cr3C2-NiCr-Mo. Plasma spray conditions for the coating materials were established adjusting stand-off distance to obtain a coating with a porosity content of ˜5%. It was found that a dissimilar coating combination of Cr2O3-NiCr-Mo and Cr3C2-NiCr-Mo provided the best antiwear performance. The addition of molybdenum was found to be beneficial to improve the wear resistance of the coating. Hardness differences between mating surfaces were also important factors in determining the wear characteristics, so that it should be controlled below 300 in Vickers hardness under dry conditions. Adhesive wear accompanying with metal transfer was a dominant wear mechanism for dry conditions.

  20. Structural, photolysis and biological studies of novel mixed metal Cu(I)-Sb(III) mixed ligand complexes.

    PubMed

    Tsiatouras, V; Banti, C N; Grześkiewicz, A M; Rossos, G; Kourkoumelis, N; Kubicki, M; Hadjikakou, S K

    2016-10-01

    Direct reaction of copper(I) halides with triphenylstibine (tpSb) and 2-mercapto-thiazolidine (tzdtH) in 1:1:1 molar ratio, results in the formation of the [CuX(μ2-S)-tzdtH)(tpSb)]2 (X=Cl (1), Br (2) and I (3)) complexes. The complexes have been characterized by melting point, FT-IR, UV-vis, (1)H NMR spectroscopic data and X-ray crystallography. Complexes 1-3 are di-nuclear and they are the first examples of mixed metals (CuSb), mixed ligand (thioamide, stibine and halogen) containing complexes. Two μ2-S (1-3) atoms bridge the two copper(I) ions with tetrahedral geometry. The coordination sphere around copper atoms is completed by one Sb from tpSb and one halogen (chlorine, bromine or iodine) atom. Intermolecular via N-H⋯X (Cl (1) and Br (2)) interactions stabilized the assembly. The short coppercopper bond distances of 3.103 (1), 3.061 (2) and 3.110, 3.108 (3) Ǻ found in 1-3 indicates d(10)-d(10) interaction between metal centers. The complexes exhibit high photo-sensitivity to UVB light. The complexes 1-3 and the already known [Cu(μ2-I)(tpSb)2]2 (4) were tested for their in vitro cytotoxic activity against human cancer cell lines: MCF-7 (breast, estrogen receptor (ER) positive), MDA-MB-231 (breast, estrogen receptor (ER) negative) and MRC-5 (normal human fetal lung fibroblast cells) with sulforhodamine B (SRB) colorimetric assay. Since estrogen receptors (ERs) are located in MCF-7, in contrast to MDA-MB-231 cells, the estrogenic effect of 1-4 on MCF-7 cells was studied by the mean of methylene blue assay. Compound 4 exhibits the highest estrogenic effect. None of 1-4 exceeds the activity of cisplatin against MCF-7 cells, but they are more active than cisplatin towards MDA-MB-231 cells. UVB light increases the effectiveness of complexes on MCF-7 cells which in the case of 4 is up to 28% higher than the corresponding initial complex (without irradiation). PMID:27599113

  1. FORENSIC INVESTIGATION OF A GENERATION OLD CIPP LINER

    EPA Science Inventory

    There is limited information regarding the in-situ performance of rehabilitation methods used for prolonging the service life of buried municipal pipeline systems. With some CIPP liners nearly 30 years in service, municipalities are expressing a strong interest in the collection ...

  2. Slope Stability of Geosynthetic Clay Liner Test Plots

    EPA Science Inventory

    Fourteen full-scale field test plots containing five types of geosynthetic clay liners (GCLs) were constructed on 2H:IV and 3H:IV slopes for the purpose of assessing slope stability. The test plots were designed to simulate typical final cover systems for landfill. Slides occurr...

  3. Fracture Mechanics Analysis of LH2 Feed Line Flow Liners

    NASA Technical Reports Server (NTRS)

    James, Mark A.; Dawicke, David S.; Brzowski, Matthew B.; Raju, Ivatury S.; Elliott, Kenny B.; Harris, Charles E.

    2006-01-01

    Inspections of the Space Shuttle Main Engine revealed fatigue cracks growing from slots in the flow liner of the liquid hydrogen (LH2) feed lines. During flight, the flow liners experience complex loading induced by flow of LH2 and the resonance characteristics of the structure. The flow liners are made of Inconel 718 and had previously not been considered a fracture critical component. However, fatigue failure of a flow liner could have catastrophic effect on the Shuttle engines. A fracture mechanics study was performed to determine if a damage tolerance approach to life management was possible and to determine the sensitivity to the load spectra, material properties, and crack size. The load spectra were derived separately from ground tests and material properties were obtained from coupon tests. The stress-intensity factors for the fatigue cracks were determined from a shell-dynamics approach that simulated the dominant resonant frequencies. Life predictions were obtained using the NASGRO life prediction code. The results indicated that adequate life could not be demonstrated for initial crack lengths of the size that could be detected by traditional NDE techniques.

  4. A flash x-ray system for diagnosing liner implosions

    SciTech Connect

    Anderson, B. G.; Oro, D. M.; Olson, R. T.; Studebaker, J. K.; Platts, D.

    2003-01-01

    This paper describes a low energy flash X-ray system that is ideal for radiographing a wide variety of experimental phenomenon on both capacitor-bank pulsed power facilities and explosively driven magnetic-flux compression experiments. The versatility of this system has allowed us to obtain both single X-radiographs of imploding liners and multiple, temporally resolved radiographic sequences of target evolution. The dynamic liner radiographs are acquired with radially oriented X-ray heads that are instrumental for observing and diagnosing liner shape and symmetry, Rayleigh-Taylor instability growth, and liner-glide plane interaction (see Fig. 1). Multiframe radiographs acquired along the axis of a cylindrical target are used to provide physical data on phenomena such as shock-driven target hydrodynamics, Richtmyer-Meshkov instability growth, spall, fiction, and equations of state. The flexibility of this X-ray system has also allowed it to be successfully fielded both at various gas and powder gun facilities and explosively driven shock physics experiments.

  5. Conductivity and transit time estimates of a soil liner

    USGS Publications Warehouse

    Krapac, I.G.; Cartwright, K.; Panno, S.V.; Hensel, B.R.; Rehfeldt, K.H.; Herzog, B.L.

    1990-01-01

    A field-scale soil linear was built to assess the feasibilty of constructing a liner to meet the saturated hydraulic conductivity requirement of the U.S. EPA (i.e., less than 1 ?? 10-7 cm/s), and to determine the breakthrough and transit times of water and tracers through the liner. The liner, 8 ?? 15 ?? 0.9 m, was constructed in 15-cm compacted lifts using a 20,037-kg pad-foot compactor and standard engineering practices. Estimated saturated hydraulic conductivities were 2.4 ?? 10-9 cm/s, based on data from large-ring infiltrometers; 4.0 ?? 10-8 cm/s from small-ring infiltrometers; and 5.0 ?? 10-8 cm/s from a water-balance analysis. These estimates were derived from 1 year of monitoring water infiltration into the linear. Breakthrough of tracers at the base of the liner was estimated to be between 2 and 13 years, depending on the method of calculation and the assumptions used in the calculation.

  6. Contoured-gap coaxial guns for imploding plasma liner experiments

    NASA Astrophysics Data System (ADS)

    Witherspoon, F. D.; Case, A.; Brockington, S.; Cassibry, J. T.; Hsu, S. C.

    2014-10-01

    Arrays of supersonic, high momentum flux plasma jets can be used as standoff compression drivers for generating spherically imploding plasma liners for driving magneto-inertial fusion, hence the name plasma-jet-driven MIF (PJMIF). HyperV developed linear plasma jets for the Plasma Liner Experiment (PLX) at LANL where two guns were successfully tested. Further development at HyperV resulted in achieving the PLX goal of 8000 μg at 50 km/s. Prior work on contoured-gap coaxial guns demonstrated an approach to control the blowby instability and achieved substantial performance improvements. For future plasma liner experiments we propose to use contoured-gap coaxial guns with small Minirailgun injectors. We will describe such a gun for a 60-gun plasma liner experiment. Discussion topics will include impurity control, plasma jet symmetry and topology (esp. related to uniformity and compactness), velocity capability, and techniques planned for achieving gun efficiency of >50% using tailored impedance matched pulse forming networks. Mach2 and UAH SPH code simulations will be included. Work supported by US DOE DE-FG02-05ER54810.

  7. Retrospective Study of In-Service CIPP Liners

    EPA Science Inventory

    Cured-in-place pipe (CIPP) has been used for rehabilitation of deteriorating wastewater pipes for nearly 30 years in the US with much success. However, little quantitative data is available regarding the performance of these liners, to verify their estimated design life of 50 yea...

  8. Risk assessment for the transportation of radioactive zeolite liners

    SciTech Connect

    Not Available

    1982-01-01

    The risk is estimated for the shipment of radioactive zeolite liners in support of the Zeolite Vitrification Demonstration Program currently underway at Pacific Northwest Laboratory under the sponsorship of the US Department of Energy. This program will establish the feasibility of zeolite vitrification as an effective means of immobilizing high-specific-activity wastes. In this risk assessment, it is assumed that two zeolite liners, each loaded around July 1, 1981 to 60,000 Ci, will be shipped by truck around January 1, 1982. However, to provide a measure of conservatism, each liner is assumed to initially hole 70,000 Ci, with the major radioisotopes as follow: /sup 90/Sr = 3000 Ci, /sup 134/Cs = 7000 Ci, /sup 137/Cs = 60,000 Ci. Should shipment take place with essentially no delay after initial loading (regardless of loading date), the shipment loading would be only 2.7% higher than that for the assumed six-month delay. This would negligibly affect the overall risk. As a result of this risk assessment, it is concluded that the transport of the radioactive zeolite liners from TMI to PNL by truck can be conducted at an insignificant level of risk to the public.

  9. Improved materials for durable rings, liners, and injector nozzles

    SciTech Connect

    Mehan, R.L.; Rairden, J.R.

    1990-06-01

    This report is the first Topical Report on the subject of Durability. The work was performed at GE's Research and Development Center (GE-CRD) in support of GE Transportations system's (GETS) effort to develop the necessary technology for future commercialization of a coal-fueled diesel power system. The technical areas covered are durable materials development for piston rings, cylinder liners, and injector nozzles. The development of an erosion-resistant nozzle for the coal-fueled locomotive was given the highest priority. Erosion tests demonstrated that nozzles built of diamond would withstand the erosive nature of the high-velocity slurry. A nozzle with diamond nozzles was designed, fabricated, and tested in a test engine. The development of piston rings and cylinder liners that could withstand the abrasive nature of the coal ash-deposited on the combustion liner was also a high priority activity. Bench scale tests were used to select optimized materials and processing conditions for plasma-deposited coatings. Tungsten carbide/cobalt was the material of choice for both the ring and liner. Small-scale engine components were built and tested. Finally, test were conducted to identify the optimum plasma spray processing conditions for deposits of tungsten carbide/cobalt mixtures. The results of these tests are described. 13 refs., 21 figs., 10 tabs.

  10. Mesoscale Probing of Local Perturbations in PBX-driven Liners

    NASA Astrophysics Data System (ADS)

    Plaksin, Igor; Guirguis, Raafat; Rodrigues, Luis; Mendes, Ricardo; Plaksin, Svyatoslav; ADAI, Univ of Coimbra; NSWC-IH Collaboration

    2013-06-01

    Efforts are aimed on experimental studies of how to improve a dynamic performance of the shaped charge jet. We postulated four basic elements to the problem: (1) The fluctuations in properties inherent in PBXs cause kinetic localizations in the detonation reaction zone (DRZ) structure, which cause (2) perturbations in the detonation products velocity and pressure, which induce (3) Perturbations in the response of the PBX-driven liner; and (4) Local perturbations/instabilities in liner are amplified during its collapse phase causing micro-fragmentations and ejected debris from the cumulative jet at initial stage, and then the incoherence and premature breakup of the resulting shaped charge jet. Spatially-resolved scenarios of each of phenomena (1-4) were obtained in experiments with copper-liners and HMX-based PBXs fabricated on maximum packing density of crystalline constituents, in which the DRZ-induced perturbations were recorded and quantitatively measured in the mesoscale range with application of the 96-channel optical analyzer MCOA-UC. Obtained experimental evidence is indicative that ejecta from the DRZ and ejecta-driven detonation cells are dominating in wide spectrum perturbations translated to a PBX-driven liner. This work was supported by the Office of Naval Research under the ONR and ONR Global Grants N00014-12-1-0477 and N62909-12-1-7131 with Drs. Clifford Bedford and Shawn Thorne Program Managers.

  11. Fracture of the alumina-bearing couple delta ceramic liner.

    PubMed

    Taheriazam, Afshin; Mohajer, Mohammad Azizbaig; Aboulghasemian, Mansoour; Hajipour, Babak

    2012-01-01

    The fracture rate of third-generation ceramic liners is greatly reduced compared with first- and second-generation liners because of improvements in the design and manufacturing process. Fractures of the alumina-bearing couple are rare for the same reason.This article describes a case of a fracture of an alumina-bearing couple delta ceramic liner without trauma history that was treated with ceramic-on-polyethylene revision total hip arthroplasty. A 57-year-old man was admitted to the hip ward because of an alumina-bearing couple delta ceramic liner fracture. He underwent hip replacement by anterior approach 18 months previously in the same center because of left hip primary osteoarthritis. He received a 54×36-mm modular press-fit cup ceramic alumina-bearing couple delta insert. Probable causes of such fractures are manufacture production failure and edge loading based on cup inclination, but in our patient, inacceptable range of motion, failure of the locking mechanism during implantation insertion, or cracking were possible causes of fracture.Although the fracture rate of third-generation alumina-bearing couples is low, we believe that it may not be possible to eliminate the actual risk of alumina head fracture. Patients should be informed about the potential for this complication before receiving an alumina-bearing couple.

  12. Evaluation of a stack: A concrete chimney with brick liner

    SciTech Connect

    Joshi, J.R.; Amin, J.A.; Porthouse, R.A.

    1995-12-31

    A 200 ft. tall stack, consisting of a concrete chimney with an independent acid proof brick liner built in the 1950`s, serving the Separations facility at the Savannah River Site (SRS), was evaluated for the performance category 3 (PC3) level of Natural Phenomena Hazards (NPH) effects. The inelastic energy absorption capacity of the concrete chimney was considered in the evaluation of the earthquake resistance, in particular, to compute the F{sub {mu}} factor. The calculated value of F{sub {mu}} exceeded 3.0, while the seismic demand for the PC3 level, using an F{sub {mu}} value of 1.5, was found to be less than the capacity of the concrete chimney. The capacity formulation of ACI 307 was modified to incorporate the effect of an after design opening on the tension side. There are considerable uncertainties in determining the earthquake resistance of the independent brick liner. The critical liner section, located at the bottom of the breeching opening, does not meet the current recommendations. A discussion is provided for the possible acceptable values for the ``Moment Reduction Factor``, R{sub w} or F{sub {mu}} for the liner. Comments are provided on the comparison of stack demands using response spectra (RS) versus time history (TH) analysis, with and without soil structure interaction (SSI) effects.

  13. 225-B Pool Cell 5 Liner Leak Investigation

    SciTech Connect

    Rasmussen, J.H., Westinghouse Hanford

    1996-06-07

    This document describes the actions taken to confirm and respond to a very small (0.046 ml/min) leak in the stainless steel liner of Hanford`s Waste Encapsulation and Storage Facility (WESF) storage pool cell 5 in Building 225-B. Manual level measurements confirmed a consistent weekly accumulation of 0.46 liters of water in the leak detection grid sump below the pool cell 5 liner. Video inspections and samples point to the capsule storage pool as the source of the water. The present leak rate corresponds to a decrease of only 0.002 inches per week in the pool cell water level, and consequently does not threaten any catastrophic loss of pool cell shielding and cooling water. The configuration of the pool cell liner, sump system, and associated risers will limit the short-term consequences of even a total liner breach to a loss of 1 inch in pool cell level. The small amount of demineralized pool cell water which has been in contact with the concrete structure is not enough to cause significant structural damage. However, ongoing water-concrete interaction increases. The pool cell leak detection sump instrumentation will be modified to improve monitoring of the leak rate in the future. Weekly manual sump level measurements continue in the interim. Contingency plans are in place to relocate the pool cell 5 capsules if the leak worsens.

  14. Filament wound metal lined propellant tanks for future Earth-to-orbit transports

    NASA Technical Reports Server (NTRS)

    Macconochie, Ian O.; Davis, Robert B.; Freeman, William T., Jr.

    1988-01-01

    For future Earth-to-orbit transport vehicles, reusability and lighter weights are sought for the main propellant tanks. To achieve this, a filament wound tank with a metal liner and an intermediate layer of foam-filled honeycomb is proposed. A hydrogen tank is used as an example. To accommodate mismatches in the expansion of liner and overwrap a design is proposed wherin the liner is configured so that the extension of the liner under pressure matches the expected contraction of the same liner due to the presence of a cryogen. In operation, the liner is pressurized at a rate such that the pressure strain matches the contraction due to decrease in temperature. As an alternate approach, compressive pre-stress is placed in the liner such that it will not separate from the overwrap. A finite element program is used to show stresses in the liner and overwrap for various tank pressures for the pre-stressed liner concept. A fracture mechanics analysis is made of the liners to determine tank life. The tank concept shown has a similar weight to the Shuttle external hydrogen tank, but the filament wound tank is expected to be reusable. Integration of the propellant tanks into a future transport vehicle is discussed.

  15. RQL Sector Rig Testing of SiC/SiC Combustor Liners

    NASA Technical Reports Server (NTRS)

    Verrilli, Michael J.; Martin, Lisa C.; Brewer, David N.

    2002-01-01

    Combustor liners, manufactured from silicon carbide fiber-reinforced silicon carbide (SiC/SiC) were tested for 260 hr using a simulated gas turbine engine cycle. This report documents the results of the last 56 hr of testing. Damage occurred in one of the six different components that make up the combustor liner set, the rich zone liner. Cracks in the rich zone liner initiated at the leading edge due to stresses resulting from the component attachment configuration. Thin film thermocouples and fiber optic pyrometers were used to measure the rich zone liner's temperature and these results are reported.

  16. High-temperature combustor liner tests in structural component response test facility

    NASA Technical Reports Server (NTRS)

    Moorhead, Paul E.

    1988-01-01

    Jet engine combustor liners were tested in the structural component response facility at NASA Lewis. In this facility combustor liners were thermally cycled to simulate a flight envelope of takeoff, cruise, and return to idle. Temperatures were measured with both thermocouples and an infrared thermal imaging system. A conventional stacked-ring louvered combustor liner developed a crack at 1603 cycles. This test was discontinued after 1728 cycles because of distortion of the liner. A segmented or float wall combustor liner tested at the same heat flux showed no significant change after 1600 cycles. Changes are being made in the facility to allow higher temperatures.

  17. Comparison of Two Acoustic Waveguide Methods for Determining Liner Impedance

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Watson, Willie R.; Tracy, Maureen B.; Parrott, Tony L.

    2001-01-01

    Acoustic measurements taken in a flow impedance tube are used to assess the relative accuracy of two waveguide methods for impedance eduction in the presence of grazing flow. The aeroacoustic environment is assumed to contain forward and backward-traveling acoustic waves, consisting of multiple modes, and uniform mean flow. Both methods require a measurement of the complex acoustic pressure profile over the length of the test liner. The Single Mode Method assumes that the sound pressure level and phase decay-rates of a single progressive mode can be extracted from this measured complex acoustic pressure profile. No a priori assumptions are made in the Finite Element. Method regarding the modal or reflection content in the measured acoustic pressure profile. The integrity of each method is initially demonstrated by how well their no-flow impedances match those acquired in a normal incidence impedance tube. These tests were conducted using ceramic tubular and conventional perforate liners. Ceramic tubular liners were included because of their impedance insensitivity to mean flow effects. Conversely, the conventional perforate liner was included because its impedance is known to be sensitive to mean flow velocity effects. Excellent comparisons between impedance values educed with the two waveguide methods in the absence of mean flow and the corresponding values educed with the normal incident impedance tube were observed. The two methods are then compared for mean flow Mach numbers up to 0.5, and are shown to give consistent results for both types of test liners. The quality of the results indicates that the Single Mode Method should be used when the measured acoustic pressure profile is clearly dominated by a single progressive mode, and the Finite Element Method should be used for all other cases.

  18. Liners and Low Luminosity AGN in the ROSAT Database

    NASA Technical Reports Server (NTRS)

    Elvis, Martin; West, Donald K. (Technical Monitor)

    2003-01-01

    This program has led to a series of papers being written and published in the Astrophysical Journal. Together these papers try to explain major parts of the LINER and low luminosity AGN puzzle. One paper ('Accretion Disk Instabilities, Cold Dark Matter Models, and Their Role in Quasar Evolution', Hatziminaoglou E., Siemiginowska A., & Elvis M., 2001, ApJ, 547, 90) describes an analytical model for the evolution of the quasar luminosity function. By combining the Press-Schechter formalism for the masses of initial structures with the luminosity distribution for a population of single mass black holes given by an unstable accretion disk an almost complete end-to-end physics-based model of quasar evolution is produced. In this model black holes spend 75% of their time in a low accretion state (at L(Edd)). This low state population of black holes is likely to be observed as the LINER and low luminosity AGNs in the local universe. Another paper ('Broad Emission Line Regions in AGN: the Link with the Accretion Power', Nicastro F., 2000, ApJ Letters, 530, L65) gives a physical basis for why low state black holes appear as LINERS. By linking the Lightman-Eardley instability in an accretion disk to the ori.gin of a wind that contains the broad emission line cloud material this model explains the large widths seen in these lines as being the Keplerian velocity of the disk at the instability radius. For LINERS the key is that below an accretion rate of 10(exp -3)M(sub Edd)the Lightman-Eardley instability falls within the innermost stable orbit of the disk, and so leaves the entire disk stable. No wind occurs, and so no broad emission lines are seen. Most LINERS are likely to be black holes in this low state. Tests of this model are being considered.

  19. A Comparative Study of Four Impedance Eduction Methodologies Using Several Test Liners

    NASA Technical Reports Server (NTRS)

    Watson, Willie R.; Jones, Michael G.

    2013-01-01

    A comparative study of four commonly used impedance eduction methods is presented for a range of liner structures and test conditions. Two of the methods are restricted to uniform flow while the other two accommodate both uniform and boundary layer flows. Measurements on five liner structures (a rigid-wall insert, a ceramic tubular liner, a wire mesh liner, a low porosity conventional liner, and a high porosity conventional liner) are obtained using the NASA Langley Grazing Flow Impedance Tube. The educed impedance of each liner is presented for forty-two test conditions (three Mach numbers and fourteen frequencies). In addition, the effects of moving the acoustic source from upstream to downstream and the refractive effects of the mean boundary layer on the wire mesh liner are investigated. The primary conclusions of the study are that: (1) more accurate results are obtained for the upstream source, (2) the uniform flow methods produce nearly identical impedance spectra at and below Mach 0.3 but significant scatter in the educed impedance occurs at the higher Mach number, (3) there is better agreement in educed impedance among the methods for the conventional liners than for the rigid-wall insert, ceramic, or wire mesh liner, and (4) the refractive effects of the mean boundary layer on the educed impedance of the wire mesh liner are generally small except at Mach 0.5.

  20. Macron Formed Liner Compression as a Practical Method for Enabling Magneto-Inertial Fusion

    SciTech Connect

    Slough, John

    2011-12-10

    The entry of fusion as a viable, competitive source of power has been stymied by the challenge of finding an economical way to provide for the confinement and heating of the plasma fuel. The main impediment for current nuclear fusion concepts is the complexity and large mass associated with the confinement systems. To take advantage of the smaller scale, higher density regime of magnetic fusion, an efficient method for achieving the compressional heating required to reach fusion gain conditions must be found. The very compact, high energy density plasmoid commonly referred to as a Field Reversed Configuration (FRC) provides for an ideal target for this purpose. To make fusion with the FRC practical, an efficient method for repetitively compressing the FRC to fusion gain conditions is required. A novel approach to be explored in this endeavor is to remotely launch a converging array of small macro-particles (macrons) that merge and form a more massive liner inside the reactor which then radially compresses and heats the FRC plasmoid to fusion conditions. The closed magnetic field in the target FRC plasmoid suppresses the thermal transport to the confining liner significantly lowering the imploding power needed to compress the target. With the momentum flux being delivered by an assemblage of low mass, but high velocity macrons, many of the difficulties encountered with the liner implosion power technology are eliminated. The undertaking to be described in this proposal is to evaluate the feasibility achieving fusion conditions from this simple and low cost approach to fusion. During phase I the design and testing of the key components for the creation of the macron formed liner have been successfully carried out. Detailed numerical calculations of the merging, formation and radial implosion of the Macron Formed Liner (MFL) were also performed. The phase II effort will focus on an experimental demonstration of the macron launcher at full power, and the demonstration

  1. The role of the substrate on the dispersion in accumulation in III-V compound semiconductor based metal-oxide-semiconductor gate stacks

    SciTech Connect

    Krylov, Igor; Ritter, Dan; Eizenberg, Moshe

    2015-09-07

    Dispersion in accumulation is a widely observed phenomenon in metal-oxide-semiconductor gate stacks based on III-V compound semiconductors. The physical origin of this phenomenon is attributed to border traps located in the dielectric material adjacent to the semiconductor. Here, we study the role of the semiconductor substrate on the electrical quality of the first layers at atomic layer deposited (ALD) dielectrics. For this purpose, either Al{sub 2}O{sub 3} or HfO{sub 2} dielectrics with variable thicknesses were deposited simultaneously on two technology important semiconductors—InGaAs and InP. Significantly larger dispersion was observed in InP based gate stacks compared to those based on InGaAs. The observed difference is attributed to a higher border trap density in dielectrics deposited on InP compared to those deposited on InGaAs. We therefore conclude that the substrate plays an important role in the determination of the electrical quality of the first dielectric monolayers deposited by ALD. An additional observation is that larger dispersion was obtained in HfO{sub 2} based capacitors compared to Al{sub 2}O{sub 3} based capacitors, deposited on the same semiconductor. This phenomenon is attributed to the lower conduction band offset rather than to a higher border trap density.

  2. Completion of the alkali metal titanium (III) pyrophosphate series: Synthesis and structure of AITiP 2O 7 ( AI = K, Rb, Cs)

    NASA Astrophysics Data System (ADS)

    Wang, Shumin; Hwu, Shiou-Jyh

    1991-05-01

    The structure of a new titanium (III) pyrophosphate RbTiP 2O 7 has been determined. It crystallizes in a monoclinic unit cell ( {P2 1}/{c}, Z = 4 ) with dimensions a = 7.542 (7) Å, b = 10.256 (2) Å, c = 8.270 (3) Å, β = 105.59 (5)°, V = 616.2 (6) Å 3. The single crystal structure refinement gives a final structure solution with R index on F20 of 0.046 for 101 variables and GOF = 1.76. RbTiP 2O 7 is isostructural with KAlP 2O 7, whose structure is also adopted by trivalent transition metal containing pyrophosphates; namely MIMoP 2O 7 ( MI = K, Rb, and Cs) and KFeP 2O 7. The potassium and cesium analogues are also synthesized. The structure differences between LiTiP 2O 7, NaTiP 2O 7 (β-phase), and (K,Rb,Cs)TiP 2O 7 are contrasted by the connectivity of the TiO 6 octahedra and P 2O 7 pyrophosphate groups. The structural relationship between RbTiP 2O 7 and previously reported BaTi 2(P 2O 7) 2 versus the role of electropositive cations in the formation of Ti(P 2O 7) nO 6-2 n units ( n is 1 for Rb + and 2 for Ba 2+) are discussed.

  3. Consideration of liners and covers in performance assessments

    SciTech Connect

    Phifer, Mark A.; Seitz, Robert R.; Suttora, Linda C.

    2014-09-18

    On-site disposal cells are in use and being considered at several United States Department of Energy (USDOE) sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These disposal cells are typically regulated by States and/or the U.S. Environmental Protection Agency under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) in addition to having to comply with requirements in DOE Order 435.1, Radioactive Waste Management due to the radioactive waste. The USDOE-Environmental Management Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these CERCLA disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to CERCLA risk assessments and DOE Order 435.1 performance assessments in support of a Record of Decision and Disposal Authorization Statement, respectively. One of the issues considered by the working group, which is addressed in this report, was how to appropriately consider the performance of covers and liners/leachate collections systems in the context of a DOE Order 435.1 performance assessment (PA). This same information may be appropriate for consideration within CERCLA risk assessments for these facilities. These OSDCs are generally developed to meet hazardous waste (HW) disposal design standards under the Resource Conservation and Recovery Act (RCRA) as well as the DOE Order 435.1 performance based standards for disposal of radioactive waste. To meet the standards for HW, the facilities typically include engineered covers and liner/leachate collection systems. Thus, when considering such facilities in the context of a DOE Order 435.1 PA, there is a need to address the evolution of performance of covers and liner/leachate collection systems in the context of meeting a performance standard considering time

  4. Template-assisted synthesis of III-nitride and metal-oxide nano-heterostructures using low-temperature atomic layer deposition for energy, sensing, and catalysis applications (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Biyikli, Necmi; Ozgit-Akgun, Cagla; Eren, Hamit; Haider, Ali; Uyar, Tamer; Kayaci, Fatma; Guler, Mustafa Ozgur; Garifullin, Ruslan; Okyay, Ali K.; Ulusoy, Gamze M.; Goldenberg, Eda

    2015-08-01

    Recent experimental research efforts on developing functional nanostructured III-nitride and metal-oxide materials via low-temperature atomic layer deposition (ALD) will be reviewed. Ultimate conformality, a unique propoerty of ALD process, is utilized to fabricate core-shell and hollow tubular nanostructures on various nano-templates including electrospun nanofibrous polymers, self-assembled peptide nanofibers, metallic nanowires, and multi-wall carbon nanotubes (MWCNTs). III-nitride and metal-oxide coatings were deposited on these nano-templates via thermal and plasma-enhanced ALD processes with thickness values ranging from a few mono-layers to 40 nm. Metal-oxide materials studied include ZnO, TiO2, HfO2, ZrO2, and Al2O3. Standard ALD growth recipes were modified so that precursor molecules have enough time to diffuse and penetrate within the layers/pores of the nano-template material. As a result, uniform and conformal coatings on high-surface area nano-templates were demonstrated. Substrate temperatures were kept below 200C and within the self-limiting ALD window, so that temperature-sensitive template materials preserved their integrity III-nitride coatings were applied to similar nano-templates via plasma-enhanced ALD (PEALD) technique. AlN, GaN, and InN thin-film coating recipes were optimized to achieve self-limiting growth with deposition temperatures as low as 100C. BN growth took place only for >350C, in which precursor decomposition occured and therefore growth proceeded in CVD regime. III-nitride core-shell and hollow tubular single and multi-layered nanostructures were fabricated. The resulting metal-oxide and III-nitride core-shell and hollow nano-tubular structures were used for photocatalysis, dye sensitized solar cell (DSSC), energy storage and chemical sensing applications. Significantly enhanced catalysis, solar efficiency, charge capacity and sensitivity performance are reported. Moreover, core-shell metal-oxide and III-nitride materials

  5. Porosity of temporary denture soft liners containing antifungal agents

    PubMed Central

    Lima, Jozely Francisca Mello; Maciel, Janaína Gomes; Hotta, Juliana; Vizoto, Ana Carolina Pero; Honório, Heitor Marques; Urban, Vanessa Migliorini; Neppelenbroek, Karin Hermana

    2016-01-01

    ABSTRACT Incorporation of antifungals in temporary denture soft liners has been recommended for denture stomatitis treatment; however, it may affect their properties. Objective: To evaluate the porosity of a tissue conditioner (Softone) and a temporary resilient liner (Trusoft) modified by minimum inhibitory concentrations (MICs) of antifungal agents for Candida albicans biofilm. Material and Methods: The porosity was measured by water absorption, based on exclusion of the plasticizer effect. Initially, it was determined by sorption isotherms that the adequate storage solution for specimens (65×10×3.3 mm) of both materials was 50% anhydrous calcium chloride (S50). Then, the porosity factor (PF) was calculated for the study groups (n=10) formed by specimens without (control) or with drug incorporation at MICs (nystatin: Ny-0.032 g, chlorhexidine diacetate: Chx-0.064 g, or ketoconazole: Ke-0.128 g each per gram of soft liner powder) after storage in distilled water or S50 for 24 h, seven and 14 d. Data were statistically analyzed by 4-way repeated measures ANOVA and Tukey's test (α=.05). Results: Ke resulted in no significant changes in PF for both liners in water over 14 days (p>0.05). Compared with the controls, Softone and Trusoft PFs were increased at 14-day water immersion only after addition of Ny and Chx, and Chx, respectively (p<0.05). Both materials showed no significant changes in PF in up to 14 days of S50 immersion, compared with the controls (p>0.05). In all experimental conditions, Softone and Trusoft PFs were significantly lower when immersed in S50 compared with distilled water (p<0.05). Conclusions: The addition of antifungals at MICs resulted in no harmful effects for the porosity of both temporary soft liners in different periods of water immersion, except for Chx and Ny in Softone and Chx in Trusoft at 14 days. No deleterious effect was observed for the porosity of both soft liners modified by the drugs at MICs over 14 days of S50 immersion

  6. Is the enthalpy of fusion of tris(acetylacetonato)metal(III) complexes affected by their potential energy in the crystal state?

    PubMed

    Sabolović, Jasmina; Mrak, Zeljko; Kostrun, Sanja; Janeković, August

    2004-12-27

    In this Article we present enthalpies of fusion and melting points obtained from new thermochemical measurements of tris(acetylacetonato)metal(III), M(acac)(3), complexes (M = Fe, Al, Cr, Mn, Co) using differential scanning calorimetry (DSC) and evaluate them in relation to their different values found in the literature. An enthalpy of fusion of 27.67 kJ mol(-)(1) was derived for Mn(acac)(3) from a symmetrical DSC thermogram captured for the first time. The enthalpy value was indirectly confirmed with the solubility measurements of Mn(acac)(3) in acetylacetone. A hypothesis has been stated that the enthalpy of fusion and the potential energy of M(acac)(3) in the crystal state may be related. To calculate molecular in-crystal potential energy, in this Article we proposed a molecular mechanics model for the M(acac)(3) class of compounds. Nine X-ray crystal structures of M(acac)(3) complexes (M = Fe, Al, V, Mn, Co, Cr, Sc) were included in the modeling. The conformational potential energy was minimized for a molecule surrounded by other molecules in the crystal lattice. The partial charges from two schemes, the electrostatic potential (ESP) fit and the natural population analysis (NPA), were used to construct two types of force fields to examine which force field type would yield a better fit with the experimental thermal properties. The final force fields were named FF-ESP and FF-NPA. Both force field sets reproduced well the experimental crystal data of nine M(acac)(3) complexes as well as of tris(3-methyl-2,4-pentanedionato-O,O')cobalt(III). Only in-crystal potential energies derived by FF-NPA yielded a significant correlation (correlation coefficient R = -0.71) with the measured enthalpies of fusion. The enthalpy of fusion for Co(acac)(3) could not be determined experimentally because of simultaneous decomposition and fusion, and it is predicted to be 33.2 kJ mol(-)(1) from the correlation regression line.

  7. Innovative Liner Concepts: Experiments and Impedance Modeling of Liners Including the Effect of Bias Flow

    NASA Technical Reports Server (NTRS)

    Kelly, Jeff; Betts, Juan Fernando; Fuller, Chris

    2000-01-01

    The study of normal impedance of perforated plate acoustic liners including the effect of bias flow was studied. Two impedance models were developed by modeling the internal flows of perforate orifices as infinite tubes with the inclusion of end corrections to handle finite length effects. These models assumed incompressible and compressible flows, respectively, between the far field and the perforate orifice. The incompressible model was used to predict impedance results for perforated plates with percent open areas ranging from 5% to 15%. The predicted resistance results showed better agreement with experiments for the higher percent open area samples. The agreement also tended to deteriorate as bias flow was increased. For perforated plates with percent open areas ranging from 1% to 5%, the compressible model was used to predict impedance results. The model predictions were closer to the experimental resistance results for the 2% to 3% open area samples. The predictions tended to deteriorate as bias flow was increased. The reactance results were well predicted by the models for the higher percent open area, but deteriorated as the percent open area was lowered (5%) and bias flow was increased. A fit was done on the incompressible model to the experimental database. The fit was performed using an optimization routine that found the optimal set of multiplication coefficients to the non-dimensional groups that minimized the least squares slope error between predictions and experiments. The result of the fit indicated that terms not associated with bias flow required a greater degree of correction than the terms associated with the bias flow. This model improved agreement with experiments by nearly 15% for the low percent open area (5%) samples when compared to the unfitted model. The fitted model and the unfitted model performed equally well for the higher percent open area (10% and 15%).

  8. Impedance Eduction in Sound Fields With Peripherally Varying Liners and Flow

    NASA Technical Reports Server (NTRS)

    Watson, W. R.; Jones, M. G.

    2015-01-01

    A two-dimensional impedance eduction theory is extended to three-dimensional sound fields and peripherally varying duct liners. The approach is to first measure the acoustic pressure field at a series of flush-mounted wall microphones located around the periphery of the flow duct. The numerical solution for the acoustic pressure field at these microphones is also obtained by solving the three-dimensional convected Helmholtz equation using the finite element method. A quadratic objective function based on the difference between the measured and finite element solution is constructed and the unknown impedance function is obtained by minimizing this objective function. Impedance spectra educed for two uniform-structure liners (a wire-mesh and a conventional liner) and a hard-soft-hard peripherally varying liner (for which the soft segment is that of the conventional liner) are presented. Results are presented at three mean flow Mach numbers and fourteen sound source frequencies. The impedance spectra of the uniform-structure liners are also computed using a two-dimensional impedance eduction theory. The primary conclusions of the study are: 1) when measured data is used with the uniform-structure liners, the three-dimensional theory reproduces the same impedance spectra as the two-dimensional theory except for frequencies corresponding to very low or very high liner attenuation; and 2) good agreement between the educed impedance spectra of the uniform structure conventional liner and the soft segment of the peripherally varying liner is obtained.

  9. A Pegasus Dynamic Liner Friction Experiment

    SciTech Connect

    Hammerberg, J.E.; Kyrala, G.A.; Oro, D.M.; Fulton, R.D.; Anderson, W.E.; Obst, A.W.; Oona, H.; Stokes, J.; Wilke, M.D.

    1999-06-28

    The authors report on a pulsed power experiment performed at the Los Alamos National Laboratory Pegasus facility which was designed to measure material flow at metal interfaces driven to high relative velocities. Material motion at and near four flat Ta/Al(6061) interfaces was measured using flash radiographic techniques. A series of fine Pb wires (407 micron diameter) was implanted in the Al normal to the interfaces. The motion of these markers under shock loading provided a picture of material motion in the Al interfacial region. The surface roughness of the interfaces was varied between 32 and 125 micro-inches. The authors discuss the implications of these measurements for constitutive models of high speed friction and interfacial morphological change.

  10. Proposed ATLAS liner design fabricated for hydrodynamics experiments on Shiva Star

    SciTech Connect

    Anderson, W. E.; Adams, C. D.; Armijo, E. V.; Bartos, J. J.; Cameron, B. J.; Garcia, F.; Henneke, B.; Randolph, B.; Salazar, M. A.; Steckle, W. P. , Jr.; Turchi, Peter J.; Gale, D.

    2001-01-01

    An entirely new cylindrical liner system has been designed and fabricated for use on the Shiva Star capacitor bank. The design incorporates features expected to be applicable to a future power flow channel of the Atlas capacitor bank with the intention of keeping any required liner design modifications to a minimum when the power flow channel at Atlas is available. Four shots were successfully conducted at Shiva Star that continued a series of hydrodynamics physics experiments started on the Los Alamos Pegasus capacitor bank. Departures from the diagnostic suite that had previously been used at Pegasus required new techniques in the fabrication of the experiment insert package. We describe new fabrication procedures that were developed by the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division to fabricate the Shiva Star experiment loads. Continuing MST-7 development of interference fit processes for liner experiment applications, current joints at the glide planes were assembled by thermal shrink fit using liquid nitrogen as a coolant. The liner material was low strength, high conductance 1100 series aluminum. The liner glide plane electrodes were machined from full hard copper rod with a 10 ramp to maintain liner to glide plane contact as the liner was imploded. The parts were fabricated with 0.015 mm radial interference fit between the liner inside diameter (ID) and the glide plane outside diameter (OD). to form the static liner current joints. The liner was assembled with some axial clearance at each end to allow slippage if any axial force was generated as the liner assembly cassette was bolted into Shiva Star, a precaution to guard against buckling the liner during installation of the load cassette. Other unique or unusual processes were developed and are described. Minor adaptations of the liner design are now being fabricated for first Atlas experiments.

  11. The evolution of instabilities during magnetically driven liner implosions.

    SciTech Connect

    Jennings, Christopher A.; Slutz, Stephen A.; Cuneo, Michael Edward; McBride, Ryan D.; Herrmann, Mark C.; Sinars, Daniel Brian

    2010-11-01

    Numerical simulations [S.A. Slutz et al Phys. Plasmas 17, 056303 (2010)] indicate that fuel magnetization and preheat could enable cylindrical liner implosions to become an efficient means to generate fusion conditions. A series of simulations has been performed to study the stability of magnetically driven liner implosions. These simulations exhibit the initial growth and saturation of an electro-thermal instability. The Rayleigh-Taylor instability further amplifies the resultant density perturbations developing a spectrum of modes initially peaked at short wavelengths. With time the spectrum of modes evolves towards longer wavelengths developing an inverse cascade. The effects of mode coupling, the radial dependence of the magnetic pressure, and the initial surface roughness will be discussed.

  12. Active Control of Liner Impedance by Varying Perforate Orifice Geometry

    NASA Technical Reports Server (NTRS)

    Ahuji, K. K.; Gaeta, R. J., Jr.

    2000-01-01

    The present work explored the feasibility of controlling the acoustic impedance of a resonant type acoustic liner. This was accomplished by translating one perforate over another of the same porosity creating a totally new perforate that had an intermediate porosity. This type of adjustable perforate created a variable orifice perforate whose orifices were non-circular. The key objective of the present study was to quantify, the degree of attenuation control that can be achieved by applying such a concept to the buried septum in a two-degree-of-freedom (2DOF) acoustic liner. An additional objective was to examine the adequacy of the existing impedance models to explain the behavior of the unique orifice shapes that result from the proposed silding perforate concept. Different orifice shapes with equivalent area were also examined to determine if highly non-circular orifices had a significant impact on the impedance.

  13. Hydrocarbon-fuel/combustion-chamber-liner materials compatibility

    NASA Technical Reports Server (NTRS)

    Gage, Mark L.

    1990-01-01

    Results of material compatibility experiments using hydrocarbon fuels in contact with copper-based combustion chamber liner materials are presented. Mil-Spec RP-1, n- dodecane, propane, and methane fuels were tested in contact with OFHC, NASA-Z, and ZrCu coppers. Two distinct test methods were employed. Static tests, in which copper coupons were exposed to fuel for long durations at constant temperature and pressure, provided compatibility data in a precisely controlled environment. Dynamic tests, using the Aerojet Carbothermal Test Facility, provided fuel and copper compatibility data under realistic booster engine service conditions. Tests were conducted using very pure grades of each fuel and fuels to which a contaminant, e.g., ethylene or methyl mercaptan, was added to define the role played by fuel impurities. Conclusions are reached as to degradation mechanisms and effects, methods for the elimination of these mechanisms, selection of copper alloy combustion chamber liners, and hydrocarbon fuel purchase specifications.

  14. Demonstration of laser speckle system on burner liner cyclic rig

    NASA Technical Reports Server (NTRS)

    Stetson, K. A.

    1986-01-01

    A demonstration test was conducted to apply speckle photogrammetry to the measurement of strains on a sample of combustor liner material in a cyclic fatigue rig. A system for recording specklegrams was assembled and shipped to the NASA Lewis Research Center, where it was set up and operated during rig tests. Data in the form of recorded specklegrams were sent back to United Technologies Research Center for processing to extract strains. Difficulties were found in the form of warping and bowing of the sample during the tests which degraded the data. Steps were taken by NASA personnel to correct this problem and further tests were run. Final data processing indicated erratic patterns of strain on the burner liner sample.

  15. FRACTURE PROPAGATION PROPENSITY OF CERAMIC LINERS DURING IMPINGEMENT-SUBLUXATION

    PubMed Central

    Elkins, Jacob M.; Pedersen, Douglas R.; Callaghan, John J.; Brown, Thomas D.

    2011-01-01

    Although improvements in materials engineering have greatly reduced fracture rates in ceramic femoral heads, concerns still exist for liners. Ceramics are vulnerable fracture due to impact, and from stress concentrations (point and line loading) such as those associated with impingement-subluxation. Thus, ceramic cup fracture propensity is presumably very sensitive to surgical cup positioning. A novel fracture mechanics finite element formulation was developed to identify cup orientations most susceptible to liner fracture propagation, for several impingement-prone patient maneuvers. Other factors being equal, increased cup inclination and increased anteversion were found to elevate fracture risk. Squatting, stooping and leaning shoe-tie maneuvers were associated with highest fracture risk. These results suggest that fracture risk can be reduced by surgeons’ decreasing cup abduction and by patients’ avoiding of specific activities. PMID:21855277

  16. Precision high energy liner implosion experiments PHELIX [1

    SciTech Connect

    Reass, William A; Baca, David M; Griego, Jeffrey R; Reinovsky, Robert E; Rousculp, Christopher L; Turchi, Peter J

    2009-01-01

    This paper describes the hardware design of a small megajoule sized transformer coupled pulse power system utilized to drive hydrodynamic liner experiments with a nominal current capability of 10 megAmperes. The resulting liner velocities and characteristics provide properties of physics interest. The capacitor banks utilize the ''Atlas'' plastic cased 60 kV, 60 kJ capacitors [2] and railgaps [3]. The air insulated marx'S are configured to dive a multi-filar toroidal transformer. The 4:1 multi-filar toroidal transformer is mechanically part of a circular disc line and this feature results in an attractive inductance budget. Because of the compact size, re-usable transformer, and resulting low maintenance cost, shot rates can be high compared to other ''large'' machines or explosively driven hydrodynamic methods. The PHELIX modeling, construction status, and test results will also be provided.

  17. Composite-Material Tanks with Chemically Resistant Liners

    NASA Technical Reports Server (NTRS)

    DeLay, Thomas K.

    2004-01-01

    Lightweight composite-material tanks with chemically resistant liners have been developed for storage of chemically reactive and/or unstable fluids . especially hydrogen peroxide. These tanks are similar, in some respects, to the ones described in gLightweight Composite-Material Tanks for Cryogenic Liquids h (MFS-31379), NASA Tech Briefs, Vol. 25, No. 1 (January, 2001), page 58; however, the present tanks are fabricated by a different procedure and they do not incorporate insulation that would be needed to prevent boil-off of cryogenic fluids. The manufacture of a tank of this type begins with the fabrication of a reusable multisegmented aluminum mandrel in the shape and size of the desired interior volume. One or more segments of the mandrel can be aluminum bosses that will be incorporated into the tank as end fittings. The mandrel is coated with a mold-release material. The mandrel is then heated to a temperature of about 400 F (approximately equal to 200 C) and coated with a thermoplastic liner material to the desired thickness [typically approxiamtely equal to 15 mils (approximately equal to 0.38 mm)] by thermal spraying. In the thermal-spraying process, the liner material in powder form is sprayed and heated to the melting temperature by a propane torch and the molten particles land on the mandrel. The sprayed liner and mandrel are allowed to cool, then the outer surface of the liner is chemically and/or mechanically etched to enhance bonding of a composite overwrap. The etched liner is wrapped with multiple layers of an epoxy resin reinforced with graphite fibers; the wrapping can be done either by manual application of epoxy-impregnated graphite cloth or by winding of epoxy-impregnated filaments. The entire assembly is heated in an autoclave to cure the epoxy. After the curing process, the multisegmented mandrel is disassembled and removed from inside, leaving the finished tank. If the tank is to be used for storing hydrogen peroxide, then the liner material

  18. Micro-beam friction liner and method of transferring energy

    DOEpatents

    Mentesana, Charles

    2007-07-17

    A micro-beam friction liner adapted to increase performance and efficiency and reduce wear in a piezoelectric motor or actuator or other device using a traveling or standing wave to transfer energy in the form of torque and momentum. The micro-beam friction liner comprises a dense array of micro-beam projections having first ends fixed relative to a rotor and second ends projecting substantially toward a plurality of teeth of a stator, wherein the micro-beam projections are compressed and bent during piezoelectric movement of the stator teeth, thereby storing the energy, and then react against the stator teeth to convert the stored energy stored to rotational energy in the rotor.

  19. Zonal isolation and evaluation for cemented horizontal liners

    SciTech Connect

    Gai, H; Summers, T.D.; Cocking, D.A.; Greaves, C.

    1996-12-01

    This paper discusses the novel application of technology in the cementing and bond evaluation from the world-record breaking extended-reach drilling (ERD) wells in Wytch Farm, where horizontal liners of the order of 800 to 1,300 m at TVD of approximately 1,600 m have been successfully cemented and perforated. Detailed analysis of the conditions by a multidisciplinary team provided some practical procedures that enabled the authors to achieve their objectives of zonal isolation and cement bond evaluation successfully. Important aspects of zonal isolation, such as the use of spiral-blade centralizers, rotating the liner, and trials of the external casing packer (ECP), are discussed in detail. Cement bond evaluation is also detailed, involving coiled tubing (CT) deployment and various bond-logging tools, including ultrasonic tools. The cement bond log (CBL) was found to be surprisingly reliable if used correctly.

  20. Sound attenuation by liners in a blown flap environment

    NASA Technical Reports Server (NTRS)

    Parthasarathy, S. P.; Vijayaraghavan, A.

    1980-01-01

    Sound propagation through a hot wall-jet flow over an absorbing wall is studied. The radiated sound field subject to the influence of flow convection and refraction is evaluated, and the nature of acoustic attenuation attributable to a sound absorbing liner is determined. Using a two-dimensional model, the noise field under the aircraft is also determined, and a slug-flow model is used to describe the influence of flow, density, and temperature on acoustic sources in jets. Results show significant changes in the radiated source due to the interference phenomenon, and a good absorber has the potential of changing the sound pressure range of variation to unity. A liner is also found to increase or decrease sound pressure, depending on the frequency.

  1. NEW APPROACHES: A hot air balloon from dustbin liners

    NASA Astrophysics Data System (ADS)

    Weaver, Nicholas

    1998-07-01

    This article describes how a simple hot air balloon, inflated by a hair dryer, can be made out of household bin liners and Sellotape. It can be used at sixth-form level as an application of the ideal gas equation, = constant, and is rather more exciting than heated pistons. It gives a taste of a simple engineering design process, although the students do have to be reasonably adept at geometry and algebra.

  2. Reliability-based condition assessment of steel containment and liners

    SciTech Connect

    Ellingwood, B.; Bhattacharya, B.; Zheng, R.

    1996-11-01

    Steel containments and liners in nuclear power plants may be exposed to aggressive environments that may cause their strength and stiffness to decrease during the plant service life. Among the factors recognized as having the potential to cause structural deterioration are uniform, pitting or crevice corrosion; fatigue, including crack initiation and propagation to fracture; elevated temperature; and irradiation. The evaluation of steel containments and liners for continued service must provide assurance that they are able to withstand future extreme loads during the service period with a level of reliability that is sufficient for public safety. Rational methodologies to provide such assurances can be developed using modern structural reliability analysis principles that take uncertainties in loading, strength, and degradation resulting from environmental factors into account. The research described in this report is in support of the Steel Containments and Liners Program being conducted for the US Nuclear Regulatory Commission by the Oak Ridge National Laboratory. The research demonstrates the feasibility of using reliability analysis as a tool for performing condition assessments and service life predictions of steel containments and liners. Mathematical models that describe time-dependent changes in steel due to aggressive environmental factors are identified, and statistical data supporting the use of these models in time-dependent reliability analysis are summarized. The analysis of steel containment fragility is described, and simple illustrations of the impact on reliability of structural degradation are provided. The role of nondestructive evaluation in time-dependent reliability analysis, both in terms of defect detection and sizing, is examined. A Markov model provides a tool for accounting for time-dependent changes in damage condition of a structural component or system. 151 refs.

  3. Thin walled liner hanger equipment enables well deepening project

    SciTech Connect

    Sutherland, J.; Weaver, C.; Aiello, P.

    1996-12-31

    Shell Canada estimates that a thin-walled, slimhole design for liner equipment can save up to $3--4 million (US) per well in deep re-entry applications by allowing existing wells to be deepened (or sidetracked) rather than drilling new wells from surface. The design makes it possible to reenter existing wells, successfully isolate depleted zones, and deepen the well into virgin-pressured reservoirs. The design includes thin-walled, close-tolerance liner hangers, liner top packers, tie-back seal assemblies, and liner setting sleeves that provide reasonable burst and collapse resistance while maintaining an inside diameter to facilitate drilling deep, deviated 4-3/4 in. hole with a tapered 2-7/8 in. x 3-1/2 in. drill string. The authors will explain the design and the rationale behind it, and illustrate its value, using case studies from Shell Canada`s Waterton field as examples. In this field, gas-producing wells originally drilled in the 1950s, `60s and `70s to depths of up to 14,760 ft (4,500 m) were completed with perforations in 7 in. casing and open hole. These wells are now being reentered in an attempt to tap new reserves. The reentries encounter particularly challenging sour-gas/low-temperature/diverse-formation-pressure conditions. The objective of the reentry program is to seal off the depleted bottom zones of the wells and tap into the same fault-repeated formations at virgin pressure, at a deeper level.

  4. Unique anisotropic optical properties of a highly stable metal-organic framework based on trinuclear iron(iii) secondary building units linked by tetracarboxylic linkers with an anthracene core.

    PubMed

    Vinogradov, A V; Milichko, V A; Zaake-Hertling, H; Aleksovska, A; Gruschinski, S; Schmorl, S; Kersting, B; Zolnhofer, E M; Sutter, J; Meyer, K; Lönnecke, P; Hey-Hawkins, E

    2016-05-01

    A highly stable metal-organic framework, [{Fe3(ACTBA)2}X·6DEF]n (1; X = monoanion), based on trinuclear iron(iii) secondary building units connected by tetracarboxylates with an anthracene core, 2,6,9,10-tetrakis(p-carboxylatophenyl)anthracene (ACTBA), is reported. Depending on the direction of light polarisation, crystals of 1 exhibit anisotropic optical properties with birefringence Δn = 0.3 (λ = 590 nm). PMID:26906040

  5. Cubane-type Cu(II)4 and Mn(II)2Mn(III)2 complexes based on pyridoxine: a versatile ligand for metal assembling.

    PubMed

    Marino, Nadia; Armentano, Donatella; Mastropietro, Teresa F; Julve, Miguel; De Munno, Giovanni; Martínez-Lillo, José

    2013-10-21

    By using Vitamin B6 in its monodeprotonated pyridoxine form (PN-H) [PN = 3-hydroxy-4,5-bis(hydroxymethyl)-2-methylpyridine], two tetranuclear compounds of formula [Mn4(PN-H)4(CH3CO2)3Cl2]Cl·2CH3OH·2H2O (1) and [Cu4(PN-H)4Cl2(H2O)2]Cl2 (2) have been synthesized and magneto-structurally characterized. 1 crystallizes in the triclinic system with space group P1 whereas 2 crystallizes in the orthorhombic system with Fdd2 as space group. They exhibit Mn(II)2Mn(III)2 (1) and Cu(II)4 (2) cubane cores containing four monodeprotonated pyridoxine groups simultaneously acting as chelating and bridging ligands (1 and 2), three bridging acetate ligands in the syn-syn conformation (1), and two terminally bound chloride anions (1 and 2) plus two coordinated water molecules (2). The electroneutrality is achieved by the presence of chloride counterions in both compounds. Tri- [Mn(1) and Mn(3)] and divalent [Mn(2) and Mn(4)] manganese centers coexist in 1, all being six-coordinate with distorted Mn(1/3)O6 and Mn(2/4)O5Cl octahedral surroundings, respectively, the equatorial Mn-O bonds being about 0.2 Å shorter at the former ones. The two crystallographically independent copper(II) ions in 2 are five-coordinate in somewhat distorted CuO5 [Cu(1)] and CuO4Cl [Cu(2)] square pyramidal geometries. The values of the intracore metal-metal separation cover the ranges 3.144(1)-3.535(1) (1) and 2.922(6)-3.376(1) Å (2). The magnetic properties of 1 and 2 were investigated in the temperature range 1.9-300 K, and they correspond to an overall antiferromagnetic behavior with susceptibility maxima at 5.0 (1) and 65.0 K (2). The analysis of the magnetic susceptibility data showed the coexistence of intracore antiferro- and ferromagnetic interactions in the two compounds. Their values compare well with those existing in the literature for the parent systems.

  6. A Physics Exploratory Experiment on Plasma Liner Formation

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Knapp, Charles E.; Kirkpatrick, Ronald C.; Siemon, Richard E.; Turchi, Peter

    2002-01-01

    Momentum flux for imploding a target plasma in magnetized target fusion (MTF) may be delivered by an array of plasma guns launching plasma jets that would merge to form an imploding plasma shell (liner). In this paper, we examine what would be a worthwhile experiment to do in order to explore the dynamics of merging plasma jets to form a plasma liner as a first step in establishing an experimental database for plasma-jets driven magnetized target fusion (PJETS-MTF). Using past experience in fusion energy research as a model, we envisage a four-phase program to advance the art of PJETS-MTF to fusion breakeven Q is approximately 1). The experiment (PLX (Plasma Liner Physics Exploratory Experiment)) described in this paper serves as Phase I of this four-phase program. The logic underlying the selection of the experimental parameters is presented. The experiment consists of using twelve plasma guns arranged in a circle, launching plasma jets towards the center of a vacuum chamber. The velocity of the plasma jets chosen is 200 km/s, and each jet is to carry a mass of 0.2 mg - 0.4 mg. A candidate plasma accelerator for launching these jets consists of a coaxial plasma gun of the Marshall type.

  7. A semi-analytic model of magnetized liner inertial fusion

    SciTech Connect

    McBride, Ryan D.; Slutz, Stephen A.

    2015-05-15

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.

  8. Magnetized Target Fusion With Centimeter-Size Liner

    SciTech Connect

    Ryutov, D

    2005-07-21

    The author concentrates on the version of magnetized target fusion (MTF) that involves 3D implosions of a wall-confined plasma with the density in the compressed state {approx} 10{sup 21}-10{sup 22} cm{sup -3}. Possible plasma configurations suitable for this approach are identified. The main physics issues are outlined (equilibrium, stability, transport, plasma-liner interaction, etc). Specific parameters of the experiment reaching the plasma Q{approx}1 are presented (Q is the ratio of the fusion yield to the energy delivered to the plasma). It is emphasized that there exists a synergy between the physics and technology of MTF and dense Z-pinches (DZP). Specific areas include the particle and heat transport in a high-beta plasma, plasma-liner interaction, liner stability, stand-off problem for the power source, reaching a rep-rate regime in the energy-producing reactor, etc. Possible use of existing pulsed-power facilities for addressing these issues is discussed.

  9. A Computational Study of the Flow Physics of Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Tam, Christopher

    2006-01-01

    The present investigation is a continuation of a previous joint project between the Florida State University and the NASA Langley Research Center Liner Physics Team. In the previous project, a study of acoustic liners, in two dimensions, inside a normal incidence impedance tube was carried out. The study consisted of two parts. The NASA team was responsible for the experimental part of the project. This involved performing measurements in an impedance tube with a large aspect ratio slit resonator. The FSU team was responsible for the computation part of the project. This involved performing direct numerical simulation (DNS) of the NASA experiment in two dimensions using CAA methodology. It was agreed that upon completion of numerical simulation, the computed values of the liner impedance were to be sent to NASA for validation with experimental results. On following this procedure good agreements were found between numerical results and experimental measurements over a wide range of frequencies and sound-pressure-level. Broadband incident sound waves were also simulated numerically and measured experimentally. Overall, good agreements were also found.

  10. Aging test results of an asphalt membrane liner

    SciTech Connect

    Buelt, J.L.; Barnes, S.M.

    1983-07-01

    The objective of the asphalt aging study described in this report was to determine the expected performance lifetime of a catalytically airblown asphalt membrane as a seepage barrier for inactive uranium mill tailings. The study, conducted by Pacific Northwest Laboratory for the Department of Energy's Uranium Mill Tailings Remedial Action Program, showed through chemical compatibility tests that the asphalt membrane is well suited for this purpose. The chemical compatibility tests were designed to accelerate the aging reactions in the asphalt and to determine the accelerated aging effect. Higher temperatures and oxygen concentrations proved to be effective acceleration parameters. By infrared spectral analysis, the asphalt was determined to have undergone 7 years of equivalent aging in a 3-month period when exposed to 40/sup 0/C and 1.7 atm oxygen pressure. However, the extent of aging was limited to a maximum penetration of 0.5% of the total liner thickness. It was concluded that the liner could be expected to be effective as a seepage barrier for at least 1000 years before the entire thickness of the liner would be degraded.

  11. Effects of tacky mat contamination on bond degradation for Chemlok/liner and NBR/liner bonds

    NASA Technical Reports Server (NTRS)

    Padilla, A. M.

    1989-01-01

    Tacky mats are placed by the rubber lay-up areas for the solid rocket motor segments. These mats dust off the shoes prior to entering the platform where the lay-up work is performed. The possibility exists that a tacky mat could be touched with gloved hands prior to handling the uncured nitride butadiene rubber (NBR). Tests were run to determine if NBR were accidentally touched would there be any degradation of the liner/NBR bond. The tacky mats were judged solely on the basis of bond degradation caused by either direct or indirect contamination. Test results all indicate that there was no notable NBR/Chemlok or liner/NBR bond degradation on samples that came into contact with the tacky mat material. Testing procedures are described. The tacky mat adhesive composition does not contain fluorocarbons or release agents that would affect bonding.

  12. Liner surface improvements for low friction piston ring packs

    NASA Astrophysics Data System (ADS)

    Anderberg, C.; Dimkovski, Z.; Rosén, B.-G.

    2014-01-01

    The development of engine components in the automotive industry is governed by several constraints such as environmental legislation and customer expectations. About a half of the frictional losses in an internal combustion engine come from the interactions between the piston assembly and cylinder liner surface. The tribological considerations in the contact between the piston ring and cylinder liner have attracted much attention over the past few decades. Many non-conventional cylinder liner finishes have been, and are being, developed with the aim to reduce friction losses and oil consumption, but the effects of the surface finish on piston ring pack performance is not well understood. One way of reducing friction in the cylinder system is to reduce the tangential load from the piston ring pack, focusing on the oil control ring. However, the side-effect of this is a disappointingly increased oil consumption. In this study a number of different cylinder liner surface specifications were developed and implemented in test engines with the aim of maintaining the level for oil consumption when decreasing the tangential load for the piston ring pack. To improve our understanding of the result, the same surfaces were evaluated in elastic and elasto-plastic rough contact and hydrodynamic flow simulation models. It is shown that oil consumption is strongly related to surface texture on the cylinder liners and at lower speeds (900-1200 rpm), a ‘rougher surface’ with a high core (e.g. Sk) and valley roughness (e.g. Svk) results in higher oil consumption. At the medium speed range (1200-3600 rpm), oil consumption continues to dominate for the ‘rough’ surfaces but with a visible influence of a lower oil consumption for a decreased roughness within the ‘rough’ surface group. ‘Smooth’ surfaces with a ‘smooth’ core (Sk), irrespective of the valley component (Svk), show similar oil consumption. For engine speeds above 3600 rpms, an increase in plateau

  13. The effect of accelerated aging on color stability of denture liners.

    PubMed

    Anil, N; Hekimoglu, C; Sahin, S

    1998-09-01

    The objective of the present study was to determine the color changes resulting from the aging process in two cold and three hot curing soft liners and two hard liners. Seven samples were fabricated for each material. The initial color measurements were made with a UV-Visible Recording Spectrophotometer. The samples were then placed in an accelerated aging chamber to simulate the aging process. The color of the samples was then measured again with a colorimeter, and the color changes (delta E) were calculated. The critical mark of color change (delta E) has been quantified by the NBS. It was concluded that cold curing soft liners were not color-stable, and that hot curing soft liners and hard liners had similar color durability. These results suggest that colorants used in cold curing soft liners must be reinforced.

  14. Acoustic properties of multiple cavity resonance liner for absorbing higher-order duct modes.

    PubMed

    Zhou, Di; Wang, Xiaoyu; Jing, Xiaodong; Sun, Xiaofeng

    2016-08-01

    This paper describes analytical and experimental studies conducted to investigate the acoustic properties of axially non-uniform multiple cavity resonance liner for absorbing higher-order duct modes. A three-dimensional analytical model is proposed based upon transfer element method. The model is assessed by making a comparison with results of a liner performance experiment concerning higher-order modes propagation, and the agreement is good. According to the present results, it is found that the performance of multiple cavity resonance liner is related to the incident sound waves. Moreover, an analysis of the corresponding response of liner perforated panel-cavity system is performed, in which the features of resonance frequency and dissipation of the system under grazing or oblique incidence condition are revealed. The conclusions can be extended to typical non-locally reacting liners with single large back-cavity, and it would be beneficial for future non-locally reacting liner design to some extent. PMID:27586753

  15. Comparative Study between Dermo, Pelite, and Seal-In X5 Liners: Effect on Patient's Satisfaction and Perceived Problems

    PubMed Central

    Ali, Sadeeq; Abu Osman, Noor Azuan; Arifin, Nooranida; Gholizadeh, Hossein; Abd Razak, Nasrul Anwar; Wan Abas, Wan Abu Bakar

    2014-01-01

    Purpose. This study aimed to compare the effect of satisfaction and perceived problems between Pelite, Dermo with shuttle lock, and Seal-In X5 liners on the transtibial amputees. Material and Methods. A total of thirty transtibial amputees (17 male, 13 female) volunteered to take part in this research. Two prostheses were fabricated for each participant. Prosthetic Evaluation Questionnaire (PEQ) was filled in by the participants with the three liners. Results. The statistics highlight that Dermo liner showed significantly higher score (P = 0.05) in walking, walking on uneven surfaces, stairs walking, fitting, donning/doffing, sitting, suspension, and overall satisfaction with Dermo liner compared with Seal-In X5 and Pelite liners. Overall satisfaction was 34% higher with Dermo liner than Seal-In X5 liner and 28% higher than Pelite liner. Participants reported less problems with Dermo liner and significant differences (P < 0.05) were recorded between the three liners in sweating, skin irritation, frustration, and pain compared with Seal-In X5 and Pelite liners. Conclusion. Participants experienced high level of satisfaction and practiced fewer problems with Dermo liner. These results showed that there is good indication to believe that Dermo liner might be a good choice for transtibial users and might help the clinicians and prosthetic practitioners in selection criteria of prosthetic liners. PMID:25184154

  16. Effect of liner and porcelain application on zirconia surface structure and composition.

    PubMed

    Alghazzawi, Tariq F; Janowski, Gregg M

    2016-01-01

    The purpose of this study was to determine if there is an effect of liner and porcelain application (layering and pressing techniques) on the surface of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP), which were exposed to permutations of liner, layered porcelain, and pressed porcelain. Scanning electron microscope (SEM)/energy dispersive spectroscope (EDS) was used to identify changes in composition and microstructure after removing liner and porcelain with hydrofluoric acid. Simulated aging was also conducted to determine the effect of liner and porcelain on low-temperature degradation. The control group had a typical equiaxed grain structure, referred to as unaffected. When covered with liner or porcelain, some areas changed in structure and composition and were termed affected. The frequency of affected structure decreased when liner was covered with either layered porcelain or pressed porcelain. There were statistical differences (P<0.05) in the composition between affected and unaffected for zirconium (layered porcelain with liner: affected=60% (0.8%) (m/m), unaffected=69% (4%), layered porcelain without liner: affected=59% (3%), unaffected=65% (3%)) and oxygen (layered porcelain with liner: affected=35% (2%), unaffected=26% (4%), layered porcelain without liner: affected=35% (3%), unaffected=30% (2%)). However, there were statistical differences (P<0.05) in the composition for zirconium and oxygen of the aged layered porcelain without liner only. The liner should not be used before porcelain application, especially when using the layering technique for zirconia restorations. Furthermore, pressing should be considered the technique of choice over layering. PMID:27445089

  17. Investigation of Liner Characteristics in the NASA Langley Curved Duct Test Rig

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Brown, Martha C.; Watson, Willie R.; Jones, Michael G.

    2007-01-01

    The Curved Duct Test Rig (CDTR), which is designed to investigate propagation of sound in a duct with flow, has been developed at NASA Langley Research Center. The duct incorporates an adaptive control system to generate a tone in the duct at a specific frequency with a target Sound Pressure Level and a target mode shape. The size of the duct, the ability to isolate higher order modes, and the ability to modify the duct configuration make this rig unique among experimental duct acoustics facilities. An experiment is described in which the facility performance is evaluated by measuring the sound attenuation by a sample duct liner. The liner sample comprises one wall of the liner test section. Sound in tones from 500 to 2400 Hz, with modes that are parallel to the liner surface of order 0 to 5, and that are normal to the liner surface of order 0 to 2, can be generated incident on the liner test section. Tests are performed in which sound is generated without axial flow in the duct and with flow at a Mach number of 0.275. The attenuation of the liner is determined by comparing the sound power in a hard wall section downstream of the liner test section to the sound power in a hard wall section upstream of the liner test section. These experimentally determined attenuations are compared to numerically determined attenuations calculated by means of a finite element analysis code. The code incorporates liner impedance values educed from measured data from the NASA Langley Grazing Incidence Tube, a test rig that is used for investigating liner performance with flow and with (0,0) mode incident grazing. The analytical and experimental results compare favorably, indicating the validity of the finite element method and demonstrating that finite element prediction tools can be used together with experiment to characterize the liner attenuation.

  18. Ultrasonic inspection of a diffusion-bonded platelet rocket chamber liner

    NASA Technical Reports Server (NTRS)

    Matson, Douglas M.; Lansaw, John T.; Suits, Michael W.; Rose, Angela W.; Danek, Peg; Nelligan, Thomas J.; Mooney, Philip P.

    1993-01-01

    An ultrasonic inspection technique, which applies pulse-echo technology for examining the rocket chamber's liner-to-jacket interface was developed, which makes it possible to characterize disbonded layers in intimate contact. The method was used to inspect a simulated flat-geometry rocket chamber liner structure with debonded liner layers and to validate the use of boron nitride powder as a flaw introduction technique.

  19. Thermal model and associated novel approach for synchrotron radiation liner with end cooling

    SciTech Connect

    Shu, Quan-Sheng; Yu, Kun; Clay, W.; Maddocks, J.; Morales, G.; Zbasnik, J.

    1993-05-01

    An end-conductive cooling approach has been developed to reduce the radial space budget of a synchrotron radiation liner to permit the maximum possible liner tube inner diameter (ID). A thermal model has also been developed to analyze the thermal performance of such liners. This approach is found to be acceptable for a liner in a 5-m-long quadrupole magnet and 3-m-long spool piece, but not for a longer 15-m dipole. The heat transfer and temperature distribution were calculated respectively along the axis of two different liner models: 20 K and 80 K liner with different thicknesses (0.5--2 mm) of liner tubes and different emissivities (0.05--0.3) of liner surface for a variety of magnets. The thermal model is also applied to the case of an 80 K liner connected directly to a 4 K beam position monitor (BPM). In order to utilize the end cooling, a good thermal joint and a compact heat exchanger are designed.

  20. Aerogel Use as a Skin Protective Liner In Space Suits and Prosthetic Limbs Project

    NASA Technical Reports Server (NTRS)

    Roberson, Luke Bennett

    2014-01-01

    Existing materials for prosthetic liners tend to be thick and airtight, causing perspiration to accumulate inside the liner and potentially causing infection and injury. The purpose of this project was to examine the suitability of aerogel for prosthetic liner applications for use in space suits and orthopedics. Three tests were performed on several types of aerogel to assess the properties of each material, and our initial findings demonstrated that these materrials would be excellent candidates for liner applications for prosthetics and space suits. The project is currently on hold until additional funding is obtained for application testing at the VH Hospitals in Tampa

  1. Efficiency of pulse high-current generator energy transfer into plasma liner energy

    NASA Astrophysics Data System (ADS)

    Oreshkin, V. I.

    2013-08-01

    The efficiency of capacitor-bank energy transfer from a high-current pulse generator into kinetic energy of a plasma liner has been analyzed. The analysis was performed using a model including the circuit equations and equations of the cylindrical shell motion. High efficiency of the energy transfer into kinetic energy of the liner is shown to be achieved only by a low-inductance generator. We considered an "ideal" liner load in which the load current is close to zero in the final of the shell compression. This load provides a high (up to 80%) efficiency of energy transfer and higher stability when compressing the liner.

  2. Gas-puff liner implosion in the configuration with helical current return rods

    SciTech Connect

    Sorokin, S. A.

    2013-02-15

    Results of experiments with double-shell gas-puff liners carried out on a high-current MIG generator (2 MA, 80 ns) are presented. To stabilize the process of liner implosion and increase the efficiency of energy transfer from the generator to the liner plasma, a current return in the form of a multifilar helix was used. The effect of the configuration of the current return on the parameters of the generated pulses of argon and neon K-shell radiation (with photon energies of 3-5 and 0.9-1.5 keV, respectively) and the neutron yield from a deuterium liner were studied.

  3. Syntheses and characterization of one-dimensional alkali metal antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs)

    SciTech Connect

    Yohannan, Jinu P.; Vidyasagar, Kanamaluru

    2015-01-15

    Three new isostructural quaternary antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs) have been synthesized by using alkali metal thiosulfate flux and structurally characterized by X-ray diffraction. Their structures contain A{sup +} ions around the [Sb{sub 2}Sn{sub 3}S{sub 10}]{sup 2−} chains, which are built from SbS{sub 3} pyramids, SnS{sub 6} octahedra and SnS{sub 4} tetrahedra. Raman and Mössbauer spectroscopic measurements corroborate the oxidation states and coordination environments of Sb(III) and Sn(IV). All three compounds are wide band gap semiconductors. Potassium compound undergoes partial exchange with strontium, cadmium and lead ions. - Graphical abstract: Syntheses, crystal structure, spectroscopic and partial ion-exchange studies of new one-dimensional alkali metal antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs) are described. - Highlights: • Syntheses of new alkali metal antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs). • Wide band gap semiconductors with one-dimensional structure. • Topotactic partial exchange of K{sup +} ions of K{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} with Sr{sup 2+}, Cd{sup 2+} and Pb{sup 2+} ions.

  4. SAGE III

    Atmospheric Science Data Center

    2016-06-15

    SAGE III Data and Information The Stratospheric Aerosol and Gas ... on the spacecraft. SAGE III produced L1 and L2 scientific data from 5/07/2002 until 12/31/2005. The flight of the second instrument is as ... Guide Documents:  Project Guide Data Products User's Guide  (PDF) Relevant Documents:  ...

  5. Reducing the distal profile of dual mobility liners can mitigate soft-tissue impingement and liner entrapment without affecting mechanical performance.

    PubMed

    Varadarajan, Kartik Mangudi; Zumbrunn, Thomas; Duffy, Michael Patrick; Patel, Rajan; Freiberg, Andrew A; Rubash, Harry E; Malchau, Henrik; Muratoglu, Orhun K

    2016-05-01

    Soft-tissue impingement with dual mobility liners can cause anterior hip pain and intra-prosthetic dislocation. The hypothesis of this study was that reducing liner profile below the equator (contoured design) can mitigate soft-tissue impingement without compromising inner-head pull-out resistance and hip joint stability. The interaction of conventional and contoured liners with anterior soft tissues was evaluated in cadaver specimens via visual observation and fluoroscopic imaging. Resistance to inner-head pull-out was evaluated via finite element analyses, and hip joint stability was evaluated by rigid-body mechanics simulation of dislocation in two modes (A, B). Cadaveric experiments showed that distal portion of conventional liners impinge on anterior hip capsule and cause iliopsoas tenting at low flexion angles (≤30°). During hip extension, the rotation imparted to the liner from posterior engagement with femoral neck was impeded by anterior soft-tissue impingement. The iliopsoas tenting was significantly reduced with contoured liners (p ≤ 0.04). Additionally, the contoured and conventional liners had identical inner-head pull-out resistance (901 N vs. 909 N), jump distance (9.4 mm mode-A, 11.7 mm mode-B) and impingement-free range of motion (47° mode-A, 29° mode-B). Thus, soft-tissue impingement with conventional dual mobility liners may be mitigated by reducing liner profile below the equator, without affecting mechanical performance. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:889-897, 2016.

  6. DEVELOPMENT OF ASME SECTION X CODE RULES FOR HIGH PRESSURE COMPOSITE HYDROGEN PRESSURE VESSELS WITH NON-LOAD SHARING LINERS

    SciTech Connect

    Rawls, G.; Newhouse, N.; Rana, M.; Shelley, B.; Gorman, M.

    2010-04-13

    The Boiler and Pressure Vessel Project Team on Hydrogen Tanks was formed in 2004 to develop Code rules to address the various needs that had been identified for the design and construction of up to 15000 psi hydrogen storage vessel. One of these needs was the development of Code rules for high pressure composite vessels with non-load sharing liners for stationary applications. In 2009, ASME approved new Appendix 8, for Section X Code which contains the rules for these vessels. These vessels are designated as Class III vessels with design pressure ranging from 20.7 MPa (3,000 ps)i to 103.4 MPa (15,000 psi) and maximum allowable outside liner diameter of 2.54 m (100 inches). The maximum design life of these vessels is limited to 20 years. Design, fabrication, and examination requirements have been specified, included Acoustic Emission testing at time of manufacture. The Code rules include the design qualification testing of prototype vessels. Qualification includes proof, expansion, burst, cyclic fatigue, creep, flaw, permeability, torque, penetration, and environmental testing.

  7. Effectiveness of covers and liners made of red mud bauxite and/or cement kiln dust for limiting acid mine drainage

    SciTech Connect

    Duchesne, J.; Doye, I.

    2005-08-01

    This paper presents a laboratory investigation to evaluate the capacity of alkaline residues to inhibit acid mine drainage. Column tests were used to evaluate the geochemical behavior of cement kiln dust (CKD) and red mud bauxite (RMB) used as covers, liners, or mixed with acid producing tailings and waste rocks. The most important indicators of neutralization are pH and the concentrations of metals in solution. Initial leachate pH of samples with an alkaline cover composed of 10% CKD or 10% of a mixture of CKD and RMB was low, but rapidly increased to near 7.0 and stabilized for the duration of this study. The use of alkaline materials as a liner had a positive effect on the reduction of Fe, SO{sub 4} and other metals such as Cu and Zn concentrations and the number of viable bacteria. In the cases where the alkaline layer was used as a liner or mixed with the waste rocks, near neutral pH values were rapidly reached in the leachate. However, in these columns the leachate pH values decreased over time.

  8. Metal-poor Stars Observed with the Magellan Telescope. III. New Extremely and Ultra Metal-poor Stars from SDSS/SEGUE and Insights on the Formation of Ultra Metal-poor Stars

    NASA Astrophysics Data System (ADS)

    Placco, Vinicius M.; Frebel, Anna; Lee, Young Sun; Jacobson, Heather R.; Beers, Timothy C.; Pena, Jose M.; Chan, Conrad; Heger, Alexander

    2015-08-01

    We report the discovery of one extremely metal-poor (EMP; [{Fe}/{{H}}] \\lt -3) and one ultra metal-poor (UMP; [{Fe}/{{H}}] \\lt -4) star selected from the Sloan Digital Sky Survey/Sloan Extension for Galactic Understanding and Exploration survey. These stars were identified as EMP candidates based on their medium-resolution (R ˜ 2000) spectra, and were followed up with high-resolution (R ˜ 35,000) spectroscopy with the Magellan/Clay Telescope. Their derived chemical abundances exhibit good agreement with those of stars with similar metallicities. We also provide new insights on the formation of the UMP stars, based on comparisons with a new set of theoretical models of supernovae (SNe) nucleosynthesis. The models were matched with 20 UMP stars found in the literature, together with one of the program stars (SDSS J1204+1201), with [{Fe}/{{H}}]=-4.34. From fitting their abundances, we find that the SNe progenitors, for stars where carbon and nitrogen are measured, had masses ranging from 20.5 {M}⊙ to 28 {M}⊙ and explosion energies from 0.3 to 0.9× {10}51 {erg}. These results are highly sensitive to the carbon and nitrogen abundance determinations, which is one of the main drivers for a future high-resolution follow-up of UMP candidates. In addition, we are able to reproduce the different CNO abundance patterns found in UMP stars with a single progenitor type by varying its mass and explosion energy. Magellan Telescopes located at Las Campanas Observatory, Chile.

  9. Development of a Tunable Electromechanical Acoustic Liner for Engine Nacelles

    NASA Technical Reports Server (NTRS)

    Liu, Fei; Sheplak, Mark; Cattafesta, Louis N., III

    2007-01-01

    This report describes the development of a tunable electromechanical Helmholtz resonator (EMHR) for engine nacelles using smart materials technology. This effort addresses both near-term and long-term goals for tunable electromechanical acoustic liner technology for the Quiet Aircraft Technology (QAT) Program. Analytical models, i.e. lumped element model (LEM) and transfer matrix (TM) representation of the EMHR, have been developed to predict the acoustic behavior of the EMHR. The models have been implemented in a MATLAB program and used to compare with measurement results. Moreover, the prediction performance of models is further improved with the aid of parameter extraction of the piezoelectric backplate. The EMHR has been experimentally investigated using standard two-microphone method (TMM). The measurement results validated both the LEM and TM models of the EMHR. Good agreement between predicted and measured impedance is obtained. Short- and open circuit loads define the limits of the tuning range using resistive and capacitive loads. There is approximately a 9% tuning limit under these conditions for the non-optimized resonator configuration studied. Inductive shunt loads result in a 3 degree-of-freedom DOF) system and an enhanced tuning range of over 20% that is not restricted by the short- and open-circuit limits. Damping coefficient ' measurements for piezoelectric backplates in a vacuum chamber are also performed and indicate that the damping is dominated by the structural damping losses, such as compliant boundaries, and other intrinsic loss mechanisms. Based on models of the EMHR, a Pareto optimization design of the EMHR has been performed for the EMHR with non-inductive loads. The EMHR with non-inductive loads is a 2DOF system with two resonant fiequencies. The tuning ranges of the two resonant frequencies of the EMHR with non-inductive loads cannot be optimized simultaneously; a trade-off (i.e., a Pareto solution) must be reached. The Pareto solution

  10. Syntheses and crystal structures of the rare-earth metal(III) bromide ortho-oxidotungstates(VI) with the formula REBr[WO4] (RE = Y, Gd-Yb)

    NASA Astrophysics Data System (ADS)

    Schustereit, Tanja; Schleid, Thomas; Hartenbach, Ingo

    2015-10-01

    The rare-earth metal(III) bromide ortho-oxidotungstates(VI) with the formula REBr[WO4] crystallize triclinically in space group P 1 bar (a = 689-693, b = 715-728, c = 1074-1107 pm, α = 103-106, β ≈ 108 and γ = 93-95°, Z = 4) for RE = Y, Gd-Yb. Their crystal structure is isotypic with the most examples of the formally analogous lanthanoid(III) bromide oxidomolybdates(VI) REBr[MoO4] with RE = Y, Pr, Nd, Sm, Gd-Lu. It contains two crystallographically different rare-earth metal(III) cations with coordination numbers of seven plus one for (RE1)3+ and seven for (RE2)3+. The (RE1)3+ cations are surrounded by three Br- and four plus one O2- anions forming distorted trigonal dodecahedra, while the (RE2)3+ cations exhibit a coordination environment of one Br- and six O2- anions in the shape of a monocapped trigonal prism. Furthermore, the structure contains two crystallographically independent, isolated tetrahedral [WO4]2- units. All these polyhedra are fused together to form 1 ∞ {REBr[WO4]} chains running along [012]. Since the title compounds, synthesized by solid-state reactions from the underlying binaries, emerge as pure phases according to X-ray powder diffractometry, spectroscopic and magnetic measurements were performed.

  11. Flow Duct Data for Validation of Acoustic Liner Codes for Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Ahuja, K. K.; Munro, Scott; Gaeta, R. J., Jr.

    2000-01-01

    The objective of the study reported here was to acquire acoustic and flow data with hard and lined duct wall duct sections for validation of a liner prediction code being developed at NASA LaRC. Both the mean flowfield and acoustic flowfields were determined in a cross-plane of the rectangular duct. A flow duct facility with acoustic drivers connected to a rectangular (4.7 x 2.0 inch) source section and a linear acoustic liner mounted downstream of the source section was used in this study. The liner section was designed to allow liner materials to be placed on all 4 walls of the duct. The test liner was of the locally-reacting type and was made from a ceramic material. The material, consisting of a tubular structure, was provided by NASA LaRC. The liner was approximately 8.89 cm (3.5 inches) thick. For the current study, only the two "short" sides of the duct were lined with liner material. The other two sides were hard walls. Two especially built instrumentation sections were attached on either sides of the liner section to allow acoustic and flow measurements to be made upstream and downstream of the liner. The two instrumentation duct sections were built to allow measurement of acoustic and flow properties at planes perpendicular to flow upstream and downstream of the liner section. The instrumentation section was also designed to provide a streamwise gradient in acoustic (complex) pressure from which the acoustic particle velocity, needed for the model validation, can be computed. Flow measurements included pressure, temperature, and velocity profiles upstream of the liner section. The in-flow sound pressure levels and phases were obtained with a microphone probe equipped with a nose cone in two cross planes upstream of the liner and two cross plane downstream of the liner. In addition to the acoustic measurements at the cross planes. axial centerline acoustic data was acquired using an axially traversing microphone probe which was traversed from a location

  12. Failure analysis of retrieved PE-UHMW acetabular liners.

    PubMed

    Laska, Anna; Archodoulaki, Vasiliki-Maria; Duscher, Bernadette

    2016-08-01

    Ultra-high molecular weight polyethylene (PE-UHMW) acetabular liners have a limited lifespan in a patient's body. There are many factors affecting the performance of the implant and furthermore the properties of the polymeric material are changing after implantation. In this work material changes according to structure and morphology and their implication on mechanical properties are in focus. The physical and mechanical properties of ten crosslinked (xL) PE-UHMW and nine conventional (conv) gamma-sterilized PE-UHMW hip components, used as sliding surface in total hip joint replacement, with different in-vivo times are compared. The evaluation of the retrieved acetabular liners is performed in view of crosslinking and conventional gamma-sterilization but also in terms of the influence of gender concerning alteration in properties. The oxidative degradation in the PE-UHMW is investigated by means of Fourier Transformed Infrared Spectroscopy (FTIR). The characterization of the morphology is carried out via differential scanning calorimetry (DSC). A depth profile of the micro-hardness and elastic modulus is taken over the cross-section of the components in order to find the influence of chemical constitution and morphology on the micro-mechanical properties. It could be shown that crosslinking and oxidative degradation influence the degree of crystallinity of the polymer. Oxidation occurs for both types of the material due to in-vivo time. Higher degree of crystallinity can be correlated to higher hardness and indentation modulus. No unequivocal superiority of crosslinked over conventional liners can be observed. The influence of sex concerning alteration of the evaluated properties matters but need to be further investigated. PMID:26849029

  13. Fusion Ignition Rocket Engine with Ballistic Ablative Lithium Liner

    NASA Technical Reports Server (NTRS)

    Martin, Adam; Eskridge, Richard; Fimognari, Peter J., III.

    2005-01-01

    Thermo-nuclear fusion may be the key to a high Isp, high specific power (low alpha) propulsion system. In a fusion system energy is liberated within, and imparted directly to, the propellant. In principle, this can overcome the performance limitations inherent in systems that require thermal power transfer across a material boundary, and/or multiple power conversion stages (NTR, NEP). A thermo-nuclear propulsion system, which attempts to overcome some of the problems inherent in the ORION concept, is described. A passive tapered liner is launched behind a vehicle, through a hole in a pusher-plate, that is connected to the vehicle by a shock-absorbing mechanism. A dense FRC plasmoid is then accelerated to high velocity (in excess of 1,000 km/s) and shot through the hole into the liner, when it has reached a given point down-range. The kinetic energy of the FRC is converted into thermal and magnetic-field energy, igniting a fusion bum in the magnetically confined plasma. The fusion reaction serves as an ignition source for the liner, which is made out of detonable materials. The energy liberated in this process is converted to thrust by the pusher-plate, as in the classic ORION concept. However with this concept, the vehicle does not carry a magazine of pre-fabricated pulse-units. A magnetic nozzle may also be used, in place of the pusher-plate. Estimates of the conditions needed to achieve a sufficient gain will be presented, along with a description of the driver characteristics. The incorporation of this concept into the propulsion system of a spacecraft will also be discussed.

  14. Failure analysis of retrieved PE-UHMW acetabular liners.

    PubMed

    Laska, Anna; Archodoulaki, Vasiliki-Maria; Duscher, Bernadette

    2016-08-01

    Ultra-high molecular weight polyethylene (PE-UHMW) acetabular liners have a limited lifespan in a patient's body. There are many factors affecting the performance of the implant and furthermore the properties of the polymeric material are changing after implantation. In this work material changes according to structure and morphology and their implication on mechanical properties are in focus. The physical and mechanical properties of ten crosslinked (xL) PE-UHMW and nine conventional (conv) gamma-sterilized PE-UHMW hip components, used as sliding surface in total hip joint replacement, with different in-vivo times are compared. The evaluation of the retrieved acetabular liners is performed in view of crosslinking and conventional gamma-sterilization but also in terms of the influence of gender concerning alteration in properties. The oxidative degradation in the PE-UHMW is investigated by means of Fourier Transformed Infrared Spectroscopy (FTIR). The characterization of the morphology is carried out via differential scanning calorimetry (DSC). A depth profile of the micro-hardness and elastic modulus is taken over the cross-section of the components in order to find the influence of chemical constitution and morphology on the micro-mechanical properties. It could be shown that crosslinking and oxidative degradation influence the degree of crystallinity of the polymer. Oxidation occurs for both types of the material due to in-vivo time. Higher degree of crystallinity can be correlated to higher hardness and indentation modulus. No unequivocal superiority of crosslinked over conventional liners can be observed. The influence of sex concerning alteration of the evaluated properties matters but need to be further investigated.

  15. A Comparative Evaluation of Shear Bond Strength Between Two Commercially Available Heat Cured Resilient Liners and Denture Base Resin with Different Surface Treatments

    PubMed Central

    Khanna, Anshul; Karani, Jyoti T.; Madria, Kunal; Mistry, Saloni

    2015-01-01

    Background Soft denture liners are widespread materials used in prosthetic dentistry. Their mechanical properties have to meet several key requirements such as adequate bond to denture base resins in order to provide right function of masticatory system and oral hygiene. Aim To evaluate and compare the shear bond strength between two commercially available liners and polymethyl methacrylate (PMMA) denture base resin with different surface treatments. Materials and Methods The two soft denture liners - Luci-Sof (silicone based liner) and Super-Soft (acrylic based liner) and a polymethyl methacrylate denture base resin (Trevalon) were chosen for the study. A total of 80 samples were made, 40 each for each of the two materials under investigation. The 40 samples were further divided into four groups, containing 10 samples each. Group I: Consisted of an untreated surface of polymethyl methacrylate which acted as the control. Group II: The surface of polymethyl methacrylate surface was sandblasted. Group III: The polymethyl methacrylate surface was treated with monomer. Group IV: The lining material was processed with acrylic resin dough. The samples after thermocycling for 500 cycles with temperatures from 5° ± 1°C to 55° ± 1°C and a 60 sec dwell time were subjected to shear loading on universal testing machine at crosshead speed of 20mm/sec. A Scanning Electron Microscope and stereomicroscope analysis of the bond interface between the liner and the denture base was conducted for all the groups of the two materials under study. Statistical Analysis Data was analyzed using independent samples t-test, analysis of variance (ANOVA) and Post-Hoc Analysis. A significance level of α = 0.05 was used for statistical analyses. Results The bond strength was significantly different between Super- Soft and Luci-Sof (p<0.05) for all surface treatments. The scanning electron microscopy observations showed that the application of surface treatments modified the surface of the

  16. Development testing of grouting and liner technology for humid sites

    SciTech Connect

    Vaughan, N.D.

    1981-01-01

    Shallow land burial, although practiced for many years, has not always secured radionuclides from the biosphere in humid environments. To develop and demonstrate improved burial technology the Engineered Test Facility was implemented. An integral part of this experiment was site characterization, with geologic and hydrologic factors as major the components. Improved techniques for burial of low-level waste were developed and tested in the laboratory before being applied in the field. The two techniques studied were membrane trench liner and grouting void spaces.

  17. Nonlinear structural and life analyses of a combustor liner

    NASA Technical Reports Server (NTRS)

    Moreno, V.; Meyers, G. J.; Kaufman, A.; Halford, G. R.

    1982-01-01

    Three dimensional, nonlinear finite element structural analyses were performed for a simulated combustor liner specimen to assess the capability of nonlinear analyses using classical inelastic material models to represent the thermoplastic creep response of the one half scale component. Results indicate continued cyclic hardening and ratcheting while experimental data suggested a stable stress strain response after only a few loading cycles. The computed stress strain history at the critical location was put into two life prediction methods, strainrange partitioning and a Pratt and Whitney combustor life prediction method to evaluate their ability to predict cyclic crack initiation. It is found that the life prediction analyses over predicted the observed cyclic crack initiation life.

  18. Liner/target/CMU cassette design and fabrication

    SciTech Connect

    Griego, Jeffrey Randall

    2011-01-07

    As part of an ongoing collaboration in pulsed power technology and condensed matter shock physics with RFNCNNIIEF, the initial design for the target and central measuring unit (CMU) for a high-pressure, high-precision ({approx}1 %), Hugoniot, equation of state (EOS) experiment is shown. VNIIEF would design and construct the disk explosive magnetic generator (DEMG) with peak currents {approx}100 MA, and cylindrical liner system with peak velocity {approx}10-20 km/s. LANL would design and construct the target and velocimetry diagnostic system. The initial mechanical design features a 2 cm diameter target system and a 1 cm diameter CMU with 32 lines of sight for PDV.

  19. Synthesis, structural, optical and anti-rheumatic activity of metal complexes derived from (E)-2-amino-N-(1-(2-aminophenyl)ethylidene)benzohydrazide (2-AAB) with Ru(III), Pd(II) and Zr(IV)

    NASA Astrophysics Data System (ADS)

    Hosny, Nasser Mohammed; Sherif, Yousery E.

    2015-02-01

    Three new metal complexes derived from Pd(II), Ru(III) and Zr(IV) with (E)-2-amino-N-(1-(2-aminophenyl)ethylidene)benzohydrazide (2-AAB) have been synthesized. The isolated complexes were characterized by elemental analyses, FT-IR, UV-Vis, ES-MS, 1H NMR, XRD, thermal analyses (TGA and DTA) and conductance. The morphology and the particle size were determined by transmittance electron microscope (TEM). The results showed that, the ligand coordinates to Pd(II) in the enol form, while it coordinates to Ru(III) and Zr(IV) in the keto form. A square planar geometry is suggested for Pd(II) complex and octahedral geometries are suggested for Ru(III) and Zr(IV) complexes. The optical band gaps of the isolated complexes were measured and indicated the semi-conductivity nature of the complexes. The anti-inflammatory and analgesic activities of the ligand and its complexes showed that, Ru(III) complex has higher effect than the well known drug "meloxicam".

  20. Numerical investigation of an impact of a top gold metallization on output power of a p-up III-N-based blue-violet edge-emitting laser diode

    NASA Astrophysics Data System (ADS)

    Kuc, M.; Sarzała, R. P.; Stańczyk, S.; Perlin, P.

    2015-06-01

    The effect of modifications in epi-side (top) gold metallization on a thermal performance and on power roll-over of blue-vio- let III-N-based p-up edge-emitting ridge-waveguide laser diode (RW EEL) was explored in this paper. The calculations were carried out using a two-dimensional self-consistent electrical-thermal model combined with a simplified optical model tuned to a RW EEL fabricated in the Institute of High Pressure Physics (Unipress). Our results suggest that with proper modifica- tions in the III-N-based RW EEL, excluding modifications in its inner structure, it is possible to considerably improve the thermal performance and, thus, increase the maximal output power.

  1. Performance evaluation of a newly developed variable rate sprayer for nursery liner applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An experimental variable-rate sprayer designed for liner applications was tested by comparing its spray deposit, coverage, and droplet density inside canopies of six nursery liner varieties with constant-rate applications. Spray samplers, including water sensitive papers (WSP) and nylon screens, wer...

  2. Optimization of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Schiller, N. H.; Born, J. C.

    2016-01-01

    This paper employs three acoustic propagation codes to explore variable-depth liner configurations for the NASA Langley Grazing Flow Impedance Tube (GFIT). The initial study demonstrates that a variable impedance can acceptably be treated as a uniform impedance if the spatial extent over which this variable impedance occurs is less than one-third of a wavelength of the incident sound. A constrained optimization study is used to design a variable-depth liner and to select an optimization metric. It also provides insight regarding how much attenuation can be achieved with variable-depth liners. Another optimization study is used to design a liner with much finer chamber depth resolution for the Mach 0.0 and 0.3 test conditions. Two liners are designed based on spatial rearrangement of chambers from this liner to determine whether the order is critical. Propagation code predictions suggest this is not the case. Both liners are fabricated via additive manufacturing and tested in the GFIT for the Mach 0.0 condition. Predicted and measured attenuations compare favorably across the full frequency range. These results clearly suggest that the chambers can be arranged in any order, thus offering the potential for innovative liner designs to minimize depth and weight.

  3. Effects of Liner Length and Attenuation on NASA Langley Impedance Eduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.

    2016-01-01

    This study explores the effects of liner length and attenuation on the CHE (convected Helmholtz equation) impedance eduction method, in which the surface impedance of an acoustic liner is inferred through an iterative process based on repeated solutions to the convected Helmholtz equation. Wire mesh-over-honeycomb and perforate-over-honeycomb acoustic liners are tested in the NASA Langley Grazing Flow Impedance Tube, and the resultant data are processed using two impedance eduction methods. The first is the CHE method, and the second is a direct method (labeled the KT method) that uses the Kumaresan and Tufts algorithm to compute the impedance directly. The CHE method has been extensively used for acoustic liner evaluation, but experiences anomalous behavior under some test conditions. It is postulated that the anomalies are related to the liner length and/or attenuation. Since the KT method only employs data measured over the length of the liner, it is expected to be unaffected by liner length. A comparison of results achieved with the two impedance eduction methods is used to explore the interactive effects of liner length and attenuation on the CHE impedance eduction method.

  4. [Comparative study of the antimicrobial effect of various cavity liners used in conservative dentistry].

    PubMed

    Pumarola Suñé, J; Espias Gómez, A; Canalda Sahli, C

    1989-01-01

    We have compared the microbiological activity of the following cavity liners: Life, Dycal II, Calcipulpe, Pure calcium hydroxide and Cavitec; against five different bacterial strains: Veillonella parvula, Bacteroides fragilis, Peptococcus s.p., Staphylococcus aureus, and Streptococcus beta hemolytic: The results demonstrate the higher antimicrobial activity of the manufactured cavity liners with calcium hydroxide base in comparison with the pure calcium hydroxide.

  5. Field-scale investigation of infiltration into a compacted soil liner

    USGS Publications Warehouse

    Panno, Samuel V.; Herzog, Beverly L.; Cartwright, Keros; Rehfeldt, Kenneth R.; Krapac, Ivan G.; Hensel, Bruce R.

    1991-01-01

    The Illinois State Geological Survey constructed and instrumented an experimental compacted soil liner. Infiltration of water into the liner has been monitored for two years. The objectives of this investigation were to determine whether a soil liner could be constructed to meet the U.S. EPA's requirement for a saturated hydraulic conductivity of less than or equal to 1.0 ?? 10-7 cm/s, to quantify the areal variability of the hydraulic properties of the liner, and to determine the transit time for water and tracers through the liner. The liner measures 8m ?? 15m ?? 0.9m and was designed and constructed to simulate compacted soil liners built at waste disposal facilities. The surface of the liner was flooded to form a pond on April 12, 1988. Since flooding, infiltration has been monitored with four large-ring (LR) and 32 small-ring (SR) infiltrometers, and a water-balance (WB) method that accounted for total infiltration and evaporation. Ring-infiltrometer and WB data were analyzed using cumulative-infiltration curves to determine infiltration fluxes. The SR data are lognormally distributed, and the SR and LR data form two statistically distinct populations. Small-ring data are nearly identical with WB data; because there is evidence of leakage in the LRs, the SR and WB data are considered more reliable.

  6. 75 FR 1596 - Grant of Authority for Subzone Status, Reynolds Packaging LLC (Aluminum Foil Liner Stock...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-12

    ... Register (74 FR 14956, 4-2-2009) and the application has been processed pursuant to the FTZ Act and the... (Aluminum Foil Liner Stock), Louisville, Kentucky Pursuant to its authority under the Foreign-Trade Zones... to the Board for authority to establish a special-purpose subzone at the aluminum foil liner...

  7. Experimental Validation of Numerical Simulations for an Acoustic Liner in Grazing Flow

    NASA Technical Reports Server (NTRS)

    Tam, Christopher K. W.; Pastouchenko, Nikolai N.; Jones, Michael G.; Watson, Willie R.

    2013-01-01

    A coordinated experimental and numerical simulation effort is carried out to improve our understanding of the physics of acoustic liners in a grazing flow as well our computational aeroacoustics (CAA) method prediction capability. A numerical simulation code based on advanced CAA methods is developed. In a parallel effort, experiments are performed using the Grazing Flow Impedance Tube at the NASA Langley Research Center. In the experiment, a liner is installed in the upper wall of a rectangular flow duct with a 2 inch by 2.5 inch cross section. Spatial distribution of sound pressure levels and relative phases are measured on the wall opposite the liner in the presence of a Mach 0.3 grazing flow. The computer code is validated by comparing computed results with experimental measurements. Good agreements are found. The numerical simulation code is then used to investigate the physical properties of the acoustic liner. It is shown that an acoustic liner can produce self-noise in the presence of a grazing flow and that a feedback acoustic resonance mechanism is responsible for the generation of this liner self-noise. In addition, the same mechanism also creates additional liner drag. An estimate, based on numerical simulation data, indicates that for a resonant liner with a 10% open area ratio, the drag increase would be about 4% of the turbulent boundary layer drag over a flat wall.

  8. USER'S GUIDE TO FLEXIBLE MEMBRANE LINER ADVISORY EXPERT SYSTEM: FLEX VERSION 3.0

    EPA Science Inventory

    The guide is a user manual for the Flexible Membrane Liner Advisory Expert System (FLEX). The system assists in determining if a proposed synthetic liner material will be chemically resistant to a proposed or anticipated leachate from a hazardous waste land disposal site. More sp...

  9. Model and analysis of a cylindrical in-line hydraulic suppressor with a solid compressible liner

    NASA Astrophysics Data System (ADS)

    Marek, K. A.; Earnhart, N. E.; Cunefare, K. A.

    2014-12-01

    An in-line hydraulic noise suppressor with a lossy, compressible liner made of foamed polyurethane liner is introduced which is intended to provide an alternative to current in-line silencing devices using compressed nitrogen gas volumes. The liner is engineered to be compressible at elevated pressures, such that it can provide effective noise abatement for practical hydraulic systems. In support of such work, a multimodal model is developed to characterize the device and the liner material. Because the hydraulic system is pressurized after insertion of the liner, the model must address liner compression and the corresponding small gaps introduced in the expansion volume; additionally, both compression and shear wave propagation must be considered in the liner. Several mode matching solutions are investigated, and a pseudoinverse mode matching method is found to provide good convergence characteristics. The multimodal model is validated against a finite element model, and also used in an optimization algorithm to estimate the material properties of a prototype liner using experimental transmission loss data. Experimental results show broadband transmission loss performance at 2.8 MPa system pressure; transmission loss decreases with increasing system pressure, and data at 4.1 MPa system pressure produces about 4 dB less transmission loss than a similarly sized commercial device. The multimodal model with estimated material properties at 2.8 MPa achieves a root mean squared error of 1.7 dB or less for two different length devices over a frequency range of 50-2000 Hz.

  10. Effect of surface treatment and liner material on the adhesion between veneering ceramic and zirconia.

    PubMed

    Yoon, Hyung-in; Yeo, In-sung; Yi, Yang-jin; Kim, Sung-hun; Lee, Jai-bong; Han, Jung-suk

    2014-12-01

    Fully sintered zirconia blocks, each with one polished surface, were treated with one of the followings: 1) no treatment, 2) airborne-particle abrasion with 50μm alumina, and 3) airborne-particle abrasion with 125μm alumina. Before veneering with glass ceramic, either liner Α or liner B were applied on the treated surfaces. All veneered blocks were subjected to shear force in a universal testing machine. For the groups with liner A, irrespective of the particle size, air abrasion on Y-TZP surfaces provided greater bond strength than polishing. Application of liner B on an abraded zirconia surface yielded no significant influence on the adhesion. In addition, specimens with liner A showed higher bond strength than those with liner B, if applied on roughened surfaces. Fractured surfaces were observed as mixed patterns in all groups. For the liner A, surface treatment was helpful in bonding with veneering ceramic, while it was ineffective for the liner B. PMID:25282467

  11. Development of reactive artificial liner using recycled materials. 1. Mechanical properties and chemical compatibility.

    PubMed

    Chin, Johnnie Y; Moon, Kyong-Whan; Park, Jae K; Park, Daniel J

    2013-07-01

    There have been several studies showing that volatile organic compounds (VOCs) can diffuse a geomembrane within days and migrate to groundwater and the surrounding environment. To ease the concern of potential pollution of the surrounding environment, an alternative artificial liner consisting of recycled materials is proposed. This composite liner consisted of recycled crumb rubber, organo-clay, silica fume, and epoxy binder. Dimethyl sulfoxide, an environmentally-friendly solvent recycled from paper pulp, was used as a plasticizer. The objective of this study was to determine the best combination of ingredients used at the initial stage and to develop artificial liners suitable for containing VOCs in leachate by comparing various physical properties. A series of screening tests including bending, tearing and elongating was performed to determine the most suitable mixture ratios. Then, more intensive tests were performed with the specimens that had the best physical properties. The new artificial liner demonstrated satisfactory mechanical properties with the minimum elongation and maximum strength after 40 years. Both artificial liners and high-density polyethylene (HDPE) specimens had ~136 kg cm(-2) after 4 months of thermal stress while the artificial liner had 40% less elongation at break than HDPE. The artificial liner's fully developed strength was about ten times stronger than HDPE. This new type of composite material that can be applied on site may provide a new perspective in liner design and alleviate the issue of potential groundwater pollution caused by landfill leachate and highly mobile VOCs which is a matter of much concern. PMID:23585500

  12. [Comparative study of the antimicrobial effect of various cavity liners used in conservative dentistry].

    PubMed

    Pumarola Suñé, J; Espias Gómez, A; Canalda Sahli, C

    1989-01-01

    We have compared the microbiological activity of the following cavity liners: Life, Dycal II, Calcipulpe, Pure calcium hydroxide and Cavitec; against five different bacterial strains: Veillonella parvula, Bacteroides fragilis, Peptococcus s.p., Staphylococcus aureus, and Streptococcus beta hemolytic: The results demonstrate the higher antimicrobial activity of the manufactured cavity liners with calcium hydroxide base in comparison with the pure calcium hydroxide. PMID:2638022

  13. Modeling of Broadband Liners Applied to the Advanced Noise Control Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.

    2015-01-01

    The broadband component of fan noise has grown in relevance with an increase in bypass ratio and incorporation of advanced fan designs. Therefore, while the attenuation of fan tones remains a major factor in engine nacelle acoustic liner design, the simultaneous reduction of broadband fan noise levels has received increased interest. As such, a previous investigation focused on improvements to an established broadband acoustic liner optimization process using the Advanced Noise Control Fan (ANCF) rig as a demonstrator. Constant-depth, double-degree of freedom and variable-depth, multi-degree of freedom liner designs were carried through design, fabrication, and testing. This paper addresses a number of areas for further research identified in the initial assessment of the ANCF study. Specifically, incident source specification and uncertainty in some aspects of the predicted liner impedances are addressed. This information is incorporated in updated predictions of the liner performance and comparisons with measurement are greatly improved. Results illustrate the value of the design process in concurrently evaluating the relative costs/benefits of various liner designs. This study also provides further confidence in the integrated use of duct acoustic propagation/radiation and liner modeling tools in the design and evaluation of novel broadband liner concepts for complex engine configurations.

  14. Leakage Performance of the GM + CCL Liner System for the MSW Landfill

    PubMed Central

    Jingjing, Fan

    2014-01-01

    The contaminants in the landfill leachate press pose a grave threat to environment of the soil and the groundwater beneath the landfill. Despite there being strict requirements in relevant provisions of both domestic and foreign countries for the design of the bottom liner system. Pollution of the soil and the groundwater still took place in a number of landfills because of the leakage. To investigate the leakage rate of the liner systems, the minimum design requirements of the liner systems are summarized according to the provisions of four countries, including China, USA, Germany, and Japan. Comparative analyses using one-dimensional transport model are conducted to study the leakage performance of these liner systems composed of geomembrance (GM) and compacted clay layer (CCL) meeting the relevant minimum design requirements. Then parametric analyses are conducted to study the effects of the hydraulic head, the thickness of GM, the hydraulic conductivity of CCL, and so forth on the leakage performance of the liner system. It is concluded that the liner system designed according to the minimum design requirements of Germany provide the best antileakage performance, while that of Japan performs the lowest. The key parameters affecting the failure time of the liner system are summarized. Finally, some suggestions for the design of the liner systems are made according to the analyses. PMID:24719569

  15. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Casing and Cementing Requirements § 250.425 What are the requirements for...-integrity test below that liner shoe, or subsequent liner shoes if set. The District Manager may approve...

  16. Evaluation of a Variable-Impedance Ceramic Matrix Composite Acoustic Liner

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

    2014-01-01

    As a result of significant progress in the reduction of fan and jet noise, there is growing concern regarding core noise. One method for achieving core noise reduction is via the use of acoustic liners. However, these liners must be constructed with materials suitable for high temperature environments and should be designed for optimum absorption of the broadband core noise spectrum. This paper presents results of tests conducted in the NASA Langley Liner Technology Facility to evaluate a variable-impedance ceramic matrix composite acoustic liner that offers the potential to achieve each of these goals. One concern is the porosity of the ceramic matrix composite material, and whether this might affect the predictability of liners constructed with this material. Comparisons between two variable-depth liners, one constructed with ceramic matrix composite material and the other constructed via stereolithography, are used to demonstrate this material porosity is not a concern. Also, some interesting observations are noted regarding the orientation of variable-depth liners. Finally, two propagation codes are validated via comparisons of predicted and measured acoustic pressure profiles for a variable-depth liner.

  17. Evaluation of Parallel-Element, Variable-Impedance, Broadband Acoustic Liner Concepts

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Howerton, Brian M.; Ayle, Earl

    2012-01-01

    Recent trends in aircraft engine design have highlighted the need for acoustic liners that provide broadband sound absorption with reduced liner thickness. Three such liner concepts are evaluated using the NASA normal incidence tube. Two concepts employ additive manufacturing techniques to fabricate liners with variable chamber depths. The first relies on scrubbing losses within narrow chambers to provide acoustic resistance necessary for sound absorption. The second employs wide chambers that provide minimal resistance, and relies on a perforated sheet to provide acoustic resistance. The variable-depth chambers used in both concepts result in reactance spectra near zero. The third liner concept employs mesh-caps (resistive sheets) embedded at variable depths within adjacent honeycomb chambers to achieve a desired impedance spectrum. Each of these liner concepts is suitable for use as a broadband sound absorber design, and a transmission line model is presented that provides good comparison with their respective acoustic impedance spectra. This model can therefore be used to design acoustic liners to accurately achieve selected impedance spectra. Finally, the effects of increasing the perforated facesheet thickness are demonstrated, and the validity of prediction models based on lumped element and wave propagation approaches is investigated. The lumped element model compares favorably with measured results for liners with thin facesheets, but the wave propagation model provides good comparisons for a wide range of facesheet thicknesses.

  18. Evaluation of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

    2015-01-01

    This paper explores the effects of variable-depth geometry on the amount of noise reduction that can be achieved with acoustic liners. Results for two variable-depth liners tested in the NASA Langley Grazing Flow Impedance Tube demonstrate significant broadband noise reduction. An impedance prediction model is combined with two propagation codes to predict corresponding sound pressure level profiles over the length of the Grazing Flow Impedance Tube. The comparison of measured and predicted sound pressure level profiles is sufficiently favorable to support use of these tools for investigation of a number of proposed variable-depth liner configurations. Predicted sound pressure level profiles for these proposed configurations reveal a number of interesting features. Liner orientation clearly affects the sound pressure level profile over the length of the liner, but the effect on the total attenuation is less pronounced. The axial extent of attenuation at an individual frequency continues well beyond the location where the liner depth is optimally tuned to the quarter-wavelength of that frequency. The sound pressure level profile is significantly affected by the way in which variable-depth segments are distributed over the length of the liner. Given the broadband noise reduction capability for these liner configurations, further development of impedance prediction models and propagation codes specifically tuned for this application is warranted.

  19. Development of reactive artificial liner using recycled materials. 1. Mechanical properties and chemical compatibility.

    PubMed

    Chin, Johnnie Y; Moon, Kyong-Whan; Park, Jae K; Park, Daniel J

    2013-07-01

    There have been several studies showing that volatile organic compounds (VOCs) can diffuse a geomembrane within days and migrate to groundwater and the surrounding environment. To ease the concern of potential pollution of the surrounding environment, an alternative artificial liner consisting of recycled materials is proposed. This composite liner consisted of recycled crumb rubber, organo-clay, silica fume, and epoxy binder. Dimethyl sulfoxide, an environmentally-friendly solvent recycled from paper pulp, was used as a plasticizer. The objective of this study was to determine the best combination of ingredients used at the initial stage and to develop artificial liners suitable for containing VOCs in leachate by comparing various physical properties. A series of screening tests including bending, tearing and elongating was performed to determine the most suitable mixture ratios. Then, more intensive tests were performed with the specimens that had the best physical properties. The new artificial liner demonstrated satisfactory mechanical properties with the minimum elongation and maximum strength after 40 years. Both artificial liners and high-density polyethylene (HDPE) specimens had ~136 kg cm(-2) after 4 months of thermal stress while the artificial liner had 40% less elongation at break than HDPE. The artificial liner's fully developed strength was about ten times stronger than HDPE. This new type of composite material that can be applied on site may provide a new perspective in liner design and alleviate the issue of potential groundwater pollution caused by landfill leachate and highly mobile VOCs which is a matter of much concern.

  20. MEASUREMENT OF THE CURRENT AND SYMMETRY OF THE IMPACT LINER ON THE NTLX EXPERIMENTS

    SciTech Connect

    J. STOKES; J. PARKER; ET AL

    2001-06-01

    A series of four liner implosion experiments, denoted the Near Term Liner Experiments (NTLX) was recently conducted on the Shiva Star capacitor bank at the Air Force Research Laboratory (AFRL). Measurement of the driving currents in these experiments is required for post-shot analysis of the liner implosion and experiments conducted in the target cylinder. A Faraday rotation measurement was fielded on Shiva Star to measure the current and compare with the current measured by a Rogowski coil technique. The Faraday rotation technique measured the 16 MA currents in these experiments with better than 1% precision. In addition, six B-dot probes were fielded at equal angles around a circle in the powerflow channel outside the liner to measure the symmetry of the liner impact on the target cylinder. The B-dot probes measure the local I-dot, which has a jump when the liner impacts the target cylinder. A high-pass filter allows one to measure this jump more accurately. From the relative timing of the jump signals, the offset of the liner axis and the circularity of liner are inferred.