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Sample records for geosynthetic clay liner

  1. 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...

  2. 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.

  3. 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.

  4. 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...

  5. Effect of temperature on hydration of geosynthetic clay liners in landfills.

    PubMed

    Barclay, Arden; Rayhani, Mohammad T

    2013-03-01

    Geosynthetic clay liners (GCLs) have gained popularity as a barrier system in modern landfill construction. As such, it is depended upon to provide a level of impermeability to prevent the escape of contaminants into the surrounding soil and groundwater. It has been proven that a GCL's hydraulic conductivity is closely related to its moisture content. GCLs are known to absorb moisture from the underlying soil after installation. In a landfill, temperatures near the liner can reach upwards of 55ºC. The effect of these elevated temperatures on the hydration process of the GCL was determined for two types of GCL over two types of subsoil: sand and clay. It was found that elevated temperatures prevented the GCL from reaching moisture content levels that would be acceptable in a real-life scenario. Temperatures in landfills could be expected to cause a GCL to reach a moisture equilibrium at roughly 16% gravimetric moisture content, where GCL at room temperature would reach higher than 100% gravimetric moisture content. The significant difference in moisture equilibrium of GCLs at different temperatures may suggest that the heat naturally produced in landfills could negatively affect the liner's hydraulic performance. The importance of allowing a GCL to properly hydrate before heat exposure must be better understood in order to minimize the potential negative effect of a landfill on our environment and our livelihood. This study also confirmed that the hydration potential of GCL depends on the method of GCL manufacture and the subsoil characteristics.

  6. 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.

  7. Characterization of Geosynthetic Clay Liner Bentonite using Micro-analytical Methods

    SciTech Connect

    Lange, K.; Rowe, R; Jamieson, H; Flemming, R; Lanzirotti, A

    2010-01-01

    In barrier design, familiarity of the structure and composition of the soil material at the micron scale is necessary for delineating the retention mechanisms of introduced metals, such as the formation of new mineral phases. In this study, the mineralogical and chemical makeup of the bentonite from a geosynthetic clay liner (GCL) was extensively characterized using a combination of conventional benchtop X-ray diffraction (XRD) and micro X-ray diffraction ({mu}XRD) with synchrotron-generated micro X-ray fluorescence ({mu}XRF) elemental mapping and {mu}XRD (S-{mu}XRD). These methods allow for the non-destructive, in situ investigation of a sample, with {micro}m spatial resolution. Synchrotron-based hard X-ray microprobes are specifically advantageous to the study of trace metals due to higher spatial resolution (<10 {micro}m) and higher analytical sensitivity (femtogram detection) than is possible using normal laboratory-based instruments. Minerals comprising less than 5% of the total bentonite sample such as gypsum, goethite and pyrite were identified that were not accessible by other conventional methods for the same GCL bentonite. Two dimensional General Area Diffraction Detector System (GADDS) images proved to be particularly advantageous in differentiating between the microcrystalline clay, which appeared as homogeneous Debye rings, and the 'spotty' or 'grainy' appearance of primary, more-coarsely-crystalline, accessory minerals. For S-{mu}XRD, the tunability of the synchrotron X-rays allowed for efficient distinction of both clay minerals at low scattering angles and in identifying varying Fe oxide minerals at higher angles. GCL samples permeated with metal-bearing mining solutions were also examined in order to consider how mechanisms of metal attenuation may be identified using the same techniques. In addition to the cation exchange capacity from the montmorillonite clay, tests showed how minerals comprising only 1-2% of the bentonite such as goethite could

  8. Characterization of humic substances in landfill leachate and impact on the hydraulic conductivity of geosynthetic clay liners.

    PubMed

    Han, Young-Soo; Lee, Jai-Young; Miller, Carol J; Franklin, Lance

    2009-05-01

    A detailed characterization was performed on the humic substances present in landfill leachate derived from the older (10-year) and younger (6-month) municipal landfill cells at a site in Inchion, Korea. The characterization focused on the humic and fulvic acid components of the leachate, relying on information gleaned from the UV/visible spectroscopy, molecular weight distribution, and Fourier transform infrared spectroscopy. The effect of the leachates, and specific components of the leachates, on the hydraulic conductivity of a geosynthetic clay liner (GCL), was evaluated. The humic acid extracted from the older leachate was composed primarily of high molecular weight and aromatic compounds, which is typical for humic acids. However, the humic acid extracted from the younger leachate showed characteristics more similar with fulvic acids, indicating that the younger humic acid was at the initial stage of humification. The hydraulic conductivity of the GCLs to the humic and fulvic acids of the older and younger leachate was similar to those permeated with the distilled deionized water (DI). However, the hydraulic conductivity of the samples tested with the raw leachate was more than 200 times the DI value. This fact suggests that cations present in leachate, rather than humic substances, are the key factor in the increase of the permeability.

  9. 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.

  10. Protective effect of overlying geosynthetic on geomembrane liner observed from landfill field tests and inclined board laboratory experiments.

    PubMed

    Chung, Moonkyung; Seo, Min Woo; Kim, Kang Suk; Park, Jun Boum

    2006-06-01

    Geosynthetic liner systems are generally installed in landfill sites to prevent toxic leachate from escaping into the adjoining environment by utilizing their impervious characteristics. Therefore, it is important to protect the geomembrane from being damaged or destroyed during all phases of landfilling, namely landfill construction, waste tipping and landfill closure. This paper presents firstly the observed performance of a geomembrane liner from a landfill site where the geomembrane liner was installed on the slopes of a Korean landfill; and secondly the results of an inclined board laboratory test. Two types of experiments were conducted to identify the protecting effect of the overlaying geosynthetic on the geomembrane liners. At a testing landfill site, the slope consisted of three different sub-inclines and two 2-m-wide intermediate levels. The sub-inclines were each 8 m in vertical height and their angle of inclination was 1: 1.5 (vertical: horizontal). The reported observations were made for a time period of approximately 1 year, until the landfill was filled with wastes to the top of the uppermost slope. In addition, inclined board laboratory tests were carried out. During the inclined board test, a base table is inclined slowly and steadily until the block located on the base table starts to slide, when the tension and displacements of two geosynthetics, namely the geomembrane liner and protecting geotextile, are measured. In conclusion, test results showed that the down-drag force generated by waste accumulation and sliding of upper material was to a large extent dissipated through the elongation of the protecting geosynthetic overlying the geomembrane and thus was not transferred to the geomembrane. Unless the protecting geosynthetic undergoes structural failure, this stress relaxation phenomenon continues to occur so that the magnitude of tensile force to be applied on the geomembrane remains marginal.

  11. REPORT OF THE 1995 WORKSHOP ON GEOSYNTHETIC CLAY LINERS

    EPA Science Inventory

    A workshop was held at the EPA's National Risk Management Research Laboratory in Cincinnati, Ohio, on August 9 and 10, 1995. On August 9, attendees were shown field plots of GCLs that have been constructed at a site in Cincinnati, and given a detailed account of the test plot la...

  12. Hydraulic conductivity of compacted clay liners permeated with inorganic salt solutions.

    PubMed

    Yilmaz, Gonca; Yetimoglu, Temel; Arasan, Seracettin

    2008-10-01

    Due to their low permeability, geosynthetic clay liners (GCLs) and compacted clay liners (CCLs) are the main materials used in waste disposal landfills. The hydraulic conductivity of GCLs and CCLs is closely related to the chemistry of the permeant fluid. In this study, the effect on the hydraulic conductivity of clays of five different inorganic salt solutions as permeant fluid was experimentally investigated. For this purpose, NaCl, NH(4)Cl, KCl, CaCl(2), and FeCl( 3) inorganic salt solutions were used at concentrations of 0.01, 0.10, 0.25, 0.50, 0.75 and 1 M. Laboratory hydraulic conductivity tests were conducted on low plasticity (CL) and high plasticity (CH) compacted raw clays. The change in electrical conductivity and pH values of the clay samples with inorganic salt solutions were also determined. The experimental test results indicated that the effect of inorganic salt solutions on CL clay was different from that on CH clay. The hydraulic conductivity was found to increase for CH clay when the salt concentrations increased whereas when the salt concentrations were increased, the hydraulic conductivity decreased for the CL clay.

  13. Attenuation of heavy metals by geosynthetics in the coal gangue-filled columns.

    PubMed

    Wang, Ping; Hu, Zhenqi; Wang, Peijun

    2013-01-01

    In the subsided areas backfilled with coal gangue, an issue of continuing environmental concern is the migration of hazardous metals to the subsurface soil and groundwater. As an effective isolation material, geosynthetics have been scarcely applied into mining areas reclamation of China. This paper describes research aimed at characterizing the behaviours of different geosynthetics in the leaching columns filled with coal gangues. Four types of geosynthetics were selected: fibres needle-punched nonwoven geotextiles, high-density polyethylene, needle-punched Na-bentonite geosynthetic clay liner (GCL-NP) and Na-bentonite geosynthetic-overbited film. Heavy metals were significantly attenuated and by monitoring aqueous solutions in the whole percolation period, negative correlation was found between pH value and concentration of heavy metals. Generally, GCL-NP showed comparatively better effects on attenuating the migration of heavy metals. According to the meta-analysis of heavy metals present in the leachates and retained in the columns, geosynthetics have good capabilities of sorption and retardation, which can delay the breakthrough time of heavy metals and retard the accumulation in the subsurface. Future research will use X-ray diffraction and micro-imaging (electron microprobe and scanning electron microscopy) to further explain retention mechanisms.

  14. Radium migration through clay liners at waste disposal sites.

    PubMed

    Bosco, M E; Cunha, I I; Saito, R T

    2001-02-05

    The migration of 226Ra through the bottom compacted clay liner of the wastewater disposal reservoirs of an industrial plant that processes uranium ore was evaluated. An instrumental method for 226Ra analysis in soils, consisting of detector calibration, the determination of detector counting efficiency, cumulative counting of both background and soil samples in regular counting intervals, and photo-peak smoothing was developed. The 226Ra was analyzed by means of its granddaughter 214Bi, at a photo-peak of 609 keV. The results showed that most of the 226Ra which diffused from the solution into the soil was retained in the upper layer of the sample, and that just a small percentage migrated to the subjacent layers. This methodology is adequate for the assessment of the migration of radionuclides through soil layers and for environmental impact studies related to contamination of soils by radionuclides.

  15. 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.

  16. Geosynthetics conquer the landfill law

    SciTech Connect

    Derian, L.; Gharios, K.M. . Solid Waste Management Div.); Kavazanjian, E. Jr.; Snow, M.S. )

    1993-12-01

    Los Angeles' last operating landfill is undergoing a 4 million m[sup 3] expansion using innovative materials in the liner system to overcome difficult site conditions. The design represents the first approved alternative in California -- and perhaps in the nation -- to the Resource Conservation and Recovery Act's Subtitle D regulations for liner systems. This article examines the regulatory journey that led to approval and the liner's design and construction. Steep slopes at Los Angeles' only operating municipal solid-waste landfill (MSW) forced designers to use an innovative geosynthetic liner and leachate collection system. Its use sets a precedent for alternatives to the prescriptive regulations for liner systems present in Subtitle D of the Resource and Conservation Recovery Act (RCRA). To provide uninterrupted service at the landfill, design and construction proceeded concurrently with regulatory approval.

  17. Degradation of geocomposite clay liners due to geochemical reactions in sodium bentonite

    SciTech Connect

    Sivalingam, S. )

    1993-03-01

    Geocomposite clay liners are commonly used as permeability barriers in landfills, hazardous waste facilities, overlying caps, secondary containments for tank farms, industrial and decorative lagoons and as slurry walls. Most recent geocomposite liners are manufactured using sodium bentonite sandwiched between two polypropylene geotextile. Na-bentonite is widely used because of its high swelling capacity, its low permeability when hydrated, high cation exchange capacity and low cost. Na-bentonite used in geo-composite liners showed degradation due to numerous geochemical reactions within the clays and cover materials at the site. The clays within the liner has undergone changes in pH from pH9 to pH5, dehydration and replacement of interlayer Na by Ca and Mg ions. Cation exchange capacity (CEC) reduced from 110 meq/100 gm to 72.5 meq/100 gm. The reduction in CEC maybe attributed to transformation of clay minerals. Analytical electron microscopy data show a decrease in Na and an increase in Ca and Mg. This observation is confirmed by the results obtained from cation exchange capacity measurements and XRD. These changes in Na-bentonite increased the permeability of the liner by 2 to 4 orders of magnitude and caused the liners to leak.

  18. Evaluating the Long-Term Performance of Geosynethic Clay Liners Exposed to Freeze-Thaw

    SciTech Connect

    Robert K. Podgorney; Jesse E. Bennett

    2006-02-01

    Geosynethic clay liners have become an increasingly common component in landfill liner and cover systems since their introduction in the early 1980’s. An important consideration for landfills and covers constructed in the frost zone of cold climates is the possible deterioration in performance due to freeze-thaw cycling over the design life of the liner or cover system, which can be up to 1,000 years. The literature contains several examples showing that geosynethic clay liners can withstand a limited number of freeze-thaw events, but data on long-term performance are lacking The objective of this study was to examine the long-term performance of geosynethic clay liners exposed to repeated freeze-thaw cycles, encompassing their application as a final cover as well as a bottom liner. Laboratory analysis of hydraulic conductivity was performed after as many as 150 freeze-thaw cycles, with no appreciable changes observed. Based upon an analytical heat transfer analysis, this equates to [at least] 150 years of field service for placement depths greater then approximately 30 cm below the surface of the liner. The long-term insusceptibility of GCLs to increased hydraulic conductivity as a response to repeated freeze-thaw cycling is largely due to the self-healing characteristics of the sodium bentonite used in their construction. GCLs perform well and maintain efficiency as a barrier to flow after 150 freeze-thaw cycles. Other factors, such as permeant chemistry, physical disturbance, desiccation, etc., may be much more important factors to consider when planning for the long-term performance of GCLs.

  19. A performance-based method for calculating the design thickness of compacted clay liners exposed to high strength leachate under simulated landfill conditions.

    PubMed

    Safari, Edwin; Jalili Ghazizade, Mahdi; Abdoli, Mohammad Ali

    2012-09-01

    Compacted clay liners (CCLs) when feasible, are preferred to composite geosynthetic liners. The thickness of CCLs is typically prescribed by each country's environmental protection regulations. However, considering the fact that construction of CCLs represents a significant portion of overall landfill construction costs; a performance based design of liner thickness would be preferable to 'one size fits all' prescriptive standards. In this study researchers analyzed the hydraulic behaviour of a compacted clayey soil in three laboratory pilot scale columns exposed to high strength leachate under simulated landfill conditions. The temperature of the simulated CCL at the surface was maintained at 40 ± 2 °C and a vertical pressure of 250 kPa was applied to the soil through a gravel layer on top of the 50 cm thick CCL where high strength fresh leachate was circulated at heads of 15 and 30 cm simulating the flow over the CCL. Inverse modelling using HYDRUS-1D indicated that the hydraulic conductivity after 180 days was decreased about three orders of magnitude in comparison with the values measured prior to the experiment. A number of scenarios of different leachate heads and persistence time were considered and saturation depth of the CCL was predicted through modelling. Under a typical leachate head of 30 cm, the saturation depth was predicted to be less than 60 cm for a persistence time of 3 years. This approach can be generalized to estimate an effective thickness of a CCL instead of using prescribed values, which may be conservatively overdesigned and thus unduly costly.

  20. 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.

  1. A review of aqueous-phase VOC transport in modern landfill liners.

    PubMed

    Edil, Tuncer B

    2003-01-01

    Leachates from municipal solid waste (MSW) and hazardous waste landfills contain a wide range of volatile organic compounds (VOCs) in addition to inorganic compounds. VOCs have been shown to migrate and contaminate the surrounding environment and impair the use of groundwater. Therefore, the effectiveness of modern landfill liner systems to minimize migration of VOCs is of concern. Most modern landfills employ a composite liner consisting of a geomembrane overlying a compacted clay liner or a geosynthetic clay liner. The geomembrane is often believed to be the primary barrier to contaminant transport. However, for VOCs, the clay component usually controls the rate of transport since VOCs are shown to diffuse through geomembrane at appreciable rates. Additionally, analyses have shown that transport of volatile organic compounds (VOCs) generally is more critical than transport of inorganic compounds (e.g., toxic heavy metals), even though VOCs are often found at lower concentrations in leachates. Therefore, the effectiveness of modern landfill liner systems to minimize migration of VOCs and transport of VOCs through clay liners and modeling of transport through composite liners merit scrutiny. This paper presents a review of recent research by the author and others on these topics. A systematic and comprehensive approach to determine mass transport parameters for transport of VOCs in liquid phase through compacted clay liners, geosynthetic clay liners (GCLs), and geomembranes has enabled to develop realistic models to predict mass flux of VOCs through modern composite liners and provide a quantitative basis to evaluate potential for transport of dissolved VOCs and the equivalency of different composite liners.

  2. 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.

  3. 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.

  4. Effects of leachate concentration on the integrity of solidified clay liners.

    PubMed

    Xue, Qiang; Zhang, Qian

    2014-03-01

    This study aimed to evaluate the impact of landfill leachate concentration on the degradation behaviour of solidified clay liners and to propose a viable mechanism for the observed degradation. The results indicated that the unconfined compressive strength of the solidified clay decreased significantly, while the hydraulic conductivity increased with the leachate concentration. The large pore proportion in the solidified clay increased and the sum of medium and micro pore proportions decreased, demonstrating that the effect on the solidified clay was evident after the degradation caused by exposure to landfill leachate. The unconfined compressive strength of the solidified clay decreased with increasing leachate concentration as the leachate changed the compact structure of the solidified clay, which are prone to deformation and fracture. The hydraulic conductivity and the large pore proportion of the solidified clay increased with the increase in leachate concentration. In contrast, the sum of medium and micro pore proportions showed an opposite trend in relation to leachate concentration, because the leachate gradually caused the medium and micro pores to form larger pores. Notably, higher leachate concentrations resulted in a much more distinctive variation in pore proportions. The hydraulic conductivity of the solidified clay was closely related to the size, distribution, and connection of pores. The proportion of the large pores showed a positive correlation with the increase of hydraulic conductivity, while the sum of the proportions of medium and micro pores showed a negative correlation.

  5. Geosynthetics in geoenvironmental engineering.

    PubMed

    Müller, Werner W; Saathoff, Fokke

    2015-06-01

    Geosynthetics are planar polymeric products, which are used in connection with soil, rock or other soil-like materials to fulfill various functions in geoenvironmental engineering. Geosynthetics are of ever-growing importance in the construction industry. Sealing of waste storage facilities to safely prevent the emission of wastewater, landfill gas and contaminated dust as well as the diffusion of pollutants into the environment and coastal protection against storms and floods and reconstruction after natural disaster are important fields of application. We will give an overview of the various geosynthetic products. Two examples of the material problems related to geosynthetics are discussed in detail: the effect of creep on the long-term performance of geocomposite drains and the numerical simulation of the interaction of soil with geogrids. Both issues are of importance for the use of these products in landfill capping systems. The various functions, which geosynthetics may fulfill in the protection of coastal lines, are illustrated by case studies. The geosynthetic market is evaluated and economical and environmental benefits, as well as environmental side effects related to the use of geosynthetics, are discussed.

  6. Geosynthetics in geoenvironmental engineering

    NASA Astrophysics Data System (ADS)

    Müller, Werner W.; Saathoff, Fokke

    2015-06-01

    Geosynthetics are planar polymeric products, which are used in connection with soil, rock or other soil-like materials to fulfill various functions in geoenvironmental engineering. Geosynthetics are of ever-growing importance in the construction industry. Sealing of waste storage facilities to safely prevent the emission of wastewater, landfill gas and contaminated dust as well as the diffusion of pollutants into the environment and coastal protection against storms and floods and reconstruction after natural disaster are important fields of application. We will give an overview of the various geosynthetic products. Two examples of the material problems related to geosynthetics are discussed in detail: the effect of creep on the long-term performance of geocomposite drains and the numerical simulation of the interaction of soil with geogrids. Both issues are of importance for the use of these products in landfill capping systems. The various functions, which geosynthetics may fulfill in the protection of coastal lines, are illustrated by case studies. The geosynthetic market is evaluated and economical and environmental benefits, as well as environmental side effects related to the use of geosynthetics, are discussed.

  7. Geosynthetics in geoenvironmental engineering

    PubMed Central

    Müller, Werner W; Saathoff, Fokke

    2015-01-01

    Geosynthetics are planar polymeric products, which are used in connection with soil, rock or other soil-like materials to fulfill various functions in geoenvironmental engineering. Geosynthetics are of ever-growing importance in the construction industry. Sealing of waste storage facilities to safely prevent the emission of wastewater, landfill gas and contaminated dust as well as the diffusion of pollutants into the environment and coastal protection against storms and floods and reconstruction after natural disaster are important fields of application. We will give an overview of the various geosynthetic products. Two examples of the material problems related to geosynthetics are discussed in detail: the effect of creep on the long-term performance of geocomposite drains and the numerical simulation of the interaction of soil with geogrids. Both issues are of importance for the use of these products in landfill capping systems. The various functions, which geosynthetics may fulfill in the protection of coastal lines, are illustrated by case studies. The geosynthetic market is evaluated and economical and environmental benefits, as well as environmental side effects related to the use of geosynthetics, are discussed. PMID:27877792

  8. 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.

  9. Hydraulic performance of compacted clay liners under simulated daily thermal cycles.

    PubMed

    Aldaeef, A A; Rayhani, M T

    2015-10-01

    Compacted clay liners (CCLs) are commonly used as hydraulic barriers in several landfill applications to isolate contaminants from the surrounding environment and minimize the escape of leachate from the landfill. Prior to waste placement in landfills, CCLs are often exposed to temperature fluctuations which can affect the hydraulic performance of the liner. Experimental research was carried out to evaluate the effects of daily thermal cycles on the hydraulic performance of CCLs under simulated landfill conditions. Hydraulic conductivity tests were conducted on different soil specimens after being exposed to various thermal and dehydration cycles. An increase in the CCL hydraulic conductivity of up to one order of magnitude was recorded after 30 thermal cycles for soils with low plasticity index (PI = 9.5%). However, medium (PI = 25%) and high (PI = 37.2%) plasticity soils did not show significant hydraulic deviation due to their self-healing potential. Overlaying the CCL with a cover layer minimized the effects of daily thermal cycles, and maintained stable hydraulic performance in the CCLs even after exposure to 60 thermal cycles. Wet-dry cycles had a significant impact on the hydraulic aspect of low plasticity CCLs. However, medium and high plasticity CCLs maintained constant hydraulic performance throughout the test intervals. The study underscores the importance of protecting the CCL from exposure to atmosphere through covering it by a layer of geomembrane or an interim soil layer.

  10. The impact of leachate from clean coal technology waste on the stability of clay and synthetic liners. Topical report, March 1, 1995--March 31, 1996

    SciTech Connect

    Brown, T.

    1998-02-01

    This project was developed to provide design criteria for landfill disposal sites used for sludges such as those generated using the Clean Coal Technologies (CCT) tested at the Public Service Company of Colorado`s Arapahoe Power Plant. The CCT wastes used were produced at the Arapahoe Plant Unit No. 4, which was equipped with the integrated dry NO{sub x}/SO{sub 2} emissions control system installed under the Clean Coal Technology Program. The investigation emphasized the potential impact of clean coal technology materials (sodium and calcium injection systems and urea injection) on the permeability and stability characteristics of clay liner materials and the stability of synthetic liner materials. Flexible-wall permeameters were used to determine the hydraulic conductivities (HC) of the clay liner materials affected by various compactive conditions. Tests were conducted using the waste materials overlying the clay liner materials through wet/dry cycles, freeze/thaw cycles, and over 120-day periods. The impact of CCT materials on the characteristics of the clay liner materials studied in this project was minimal. The HC measurements of the waste/clay liner systems were similar to those of the water/clay liner systems. HC decreased for clay liners compacted at moisture levels slightly higher than optimum (standard Procter) and increased for liners compacted at moisture levels lower than optimum (standard Procter). Although some swelling was evident in the sodium materials, the sludge materials did not have a negative impact on the integrity of the liners over 120-day tests. Wet/dry cycles tended to result in lower HC, while freeze/thaw cycles substantially increased HC for the liners tested.

  11. Analysis of diffusion-adsorption equivalency of landfill liner systems for organic contaminants.

    PubMed

    Xie, Haijian; Chen, Yunmin; Ke, Han; Tang, Xiaowu; Chen, Renpeng

    2009-01-01

    The equivalence between multilayered barriers regarding diffusion and adsorption was studied. The bottom boundary of the liner system is defined by assuming concentration continuous and flux continuous conditions of the contaminant between the bottom liner layer and the underlying soil. Five different liner systems were compared in terms of solute breakthrough time. The results of the analysis showed that breakthrough time of the hydrophobic organic compounds for a 2-meter-thick compacted clay liner (CCL) could be 3-4 orders of magnitude is greater than the breakthrough time for a geosynthetic clay liner (GCL) composite liner. The GM/GCL and GM/CCL composite liner systems provide a better diffusion barrier for the hydrophilic organic compounds than that for the hydrophobic compounds due to their different Henry's coefficient. The calculated breakthrough times of the organic contaminants for the Chinese standard liner systems were found to be generally greater than those for the GCL alternatives, for the specific conditions examined. If the distribution coefficient increases to 2.8 for the hydrophobic compounds or 1.0 for the hydrophilic compounds, the thickness of the attenuation layer needed to achieve the same breakthrough time as the standard liner systems can be reduced by a factor of about 1.9-2.4. As far as diffusive and adsorption contaminant transport are concerned, GM or GCL is less effective than CCL.

  12. Hydraulic performance of Compacted Clay Liners (CCLs) under combined temperature and leachate exposures.

    PubMed

    Aldaeef, A A; Rayhani, M T

    2014-12-01

    Experimental investigations were carried out to investigate the effect of thermo-chemical exposures on the hydraulic performance of Compacted Clay Liners (CCLs) in landfills. Hydraulic conductivity of most CCL specimens was increased by two to three times their initial values when exposed to 55 °C for 75 days. CCL specimens also experienced increases in their hydraulic conductivities when exposed to leachate at room temperature. This behaviour could be due to the decrease in viscosity when the permeant was changed from tap water to leachate. However, as the leachate exposure time exceeded the first 15 days, hydraulic conductivity readings decreased to as much as one order of magnitude after 75 days of leachate permeation at room temperature. The gradual decrease in the CCLs hydraulic conductivities was most likely due to chemical precipitation and clogging of pore voids within the soils which seemed to reduce the effective pore volume. The rate of hydraulic conductivity reduction due to leachate permeation was slower at higher temperatures, which was attributed to the lower permeant viscosity and lower clogging occurrence. The observed hydraulic behaviours were correlated to the physical, mineral, and chemical properties of the CCLs and described below.

  13. Hydraulic conductivity study of compacted clay soils used as landfill liners for an acidic waste

    SciTech Connect

    Hamdi, Noureddine; Srasra, Ezzeddine

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Examined the hydraulic conductivity evolution as function of dry density of Tunisian clay soil. Black-Right-Pointing-Pointer Follow the hydraulic conductivity evolution at long-term of three clay materials using the waste solution (pH=2.7). Black-Right-Pointing-Pointer Determined how compaction affects the hydraulic conductivity of clay soils. Black-Right-Pointing-Pointer Analyzed the concentration of F and P and examined the retention of each soil. - Abstract: Three natural clayey soils from Tunisia were studied to assess their suitability for use as a liner for an acid waste disposal site. An investigation of the effect of the mineral composition and mechanical compaction on the hydraulic conductivity and fluoride and phosphate removal of three different soils is presented. The hydraulic conductivity of these three natural soils are 8.5 Multiplication-Sign 10{sup -10}, 2.08 Multiplication-Sign 10{sup -9} and 6.8 Multiplication-Sign 10{sup -10} m/s for soil-1, soil-2 and soil-3, respectively. Soil specimens were compacted under various compaction strains in order to obtain three wet densities (1850, 1950 and 2050 kg/m{sup 3}). In this condition, the hydraulic conductivity (k) was reduced with increasing density of sample for all soils. The test results of hydraulic conductivity at long-term (>200 days) using acidic waste solution (pH = 2.7, charged with fluoride and phosphate ions) shows a decrease in k with time only for natural soil-1 and soil-2. However, the specimens of soil-2 compressed to the two highest densities (1950 and 2050 kg/m{sup 3}) are cracked after 60 and 20 days, respectively, of hydraulic conductivity testing. This damage is the result of a continued increase in the internal stress due to the swelling and to the effect of aggressive wastewater. The analysis of anions shows that the retention of fluoride is higher compared to phosphate and soil-1 has the highest sorption capacity.

  14. A steady-state approach for evaluating the impact of solute transport through composite liners on groundwater quality.

    PubMed

    Foose, Gary J

    2010-01-01

    New adaptations of analytical equations for predicting the impact of solute transport through composite landfill liners on groundwater quality for steady-state conditions are presented. Analytical equations are developed for evaluating average concentration and mass flow rate in an underlying aquifer resulting from diffusion of volatile organic compounds (VOCs) through intact composite liners and transport of inorganic constituents through defects in composite liners. The equations are applied to evaluate the effectiveness and equivalency of composite liners having either a 0.6 m-thick compacted soil liner or a 6.5 mm-thick geosynthetic clay liner (GCL) overlying an intermediate attenuation layer and an aquifer having horizontal flow. Example analyses for designing composite liners meeting particular performance criteria are also provided. The analytical equations are relatively simple to apply and can be used for preliminary design and analysis, to evaluate experimental results, and to possibly verify more complex numerical models for evaluating the impact of landfills on groundwater quality if consistency of the assumptions of the analytical equations and the more complex numerical models can be specified.

  15. An analytical model for volatile organic compound transport through a composite liner consisting of a geomembrane, a GCL, and a soil liner.

    PubMed

    Xie, Haijian; Jiang, Yuansheng; Zhang, Chunhua; Feng, Shijin

    2015-02-01

    An analytical model for volatile organic compounds (VOCs) transport through a composite liner consisting of a geomembrane (GM), a geosynthetic clay liner (GCL), and a soil liner (SL) was developed for the assessment of the performance of this triple liner system. Both advection through the defects of GM and diffusion in the intact GM were considered in the model, and dimensionless analytical solution was obtained. The soil concentration profiles obtained by the proposed analytical solution have a good agreement with those obtained by the finite-layer-based software POLLUTE v7. The effects of leachate head, length of the connected wrinkles, and the interface transmissivity of GM/GCL on the breakthrough curves of the liner system were then investigated. Results show that the 30-year base flux of the liner system for the case with leachate head = 10 m and length of the connected wrinkles = 1,000 m can be over 60 times greater than that of the pure diffusion case. The length of the connected wrinkles of the GM has greater influence on the base flux of the liner system than on the base concentration. The interface transmissivity has negligible effect on the solute breakthrough curves of the liner system for relatively low values of the length of the connected wrinkles (e.g., <100 m). The groundwater protection level achieved by GM/CCL is more effective than that by GM/GCL/SL in the earlier times. However, the steady state base flux for GM/GCL/SL can be seven to eight times lower than that for GM/CCL. The analytical solution can also be used for experimental data fitting, verification of complicated numerical models, and preliminary design of composite liners.

  16. Hydraulic conductivity study of compacted clay soils used as landfill liners for an acidic waste.

    PubMed

    Hamdi, Noureddine; Srasra, Ezzeddine

    2013-01-01

    Three natural clayey soils from Tunisia were studied to assess their suitability for use as a liner for an acid waste disposal site. An investigation of the effect of the mineral composition and mechanical compaction on the hydraulic conductivity and fluoride and phosphate removal of three different soils is presented. The hydraulic conductivity of these three natural soils are 8.5 × 10(-10), 2.08 × 10(-9) and 6.8 × 10(-10)m/s for soil-1, soil-2 and soil-3, respectively. Soil specimens were compacted under various compaction strains in order to obtain three wet densities (1850, 1950 and 2050 kg/m(3)). In this condition, the hydraulic conductivity (k) was reduced with increasing density of sample for all soils. The test results of hydraulic conductivity at long-term (>200 days) using acidic waste solution (pH=2.7, charged with fluoride and phosphate ions) shows a decrease in k with time only for natural soil-1 and soil-2. However, the specimens of soil-2 compressed to the two highest densities (1950 and 2050 kg/m(3)) are cracked after 60 and 20 days, respectively, of hydraulic conductivity testing. This damage is the result of a continued increase in the internal stress due to the swelling and to the effect of aggressive wastewater. The analysis of anions shows that the retention of fluoride is higher compared to phosphate and soil-1 has the highest sorption capacity.

  17. Steady-state analytical models for performance assessment of landfill composite liners.

    PubMed

    Xie, Haijian; Jiang, Yuansheng; Zhang, Chunhua; Feng, Shijin; Qiu, Zhanhong

    2015-08-01

    One-dimensional mathematical models were developed for organic contaminant transport through landfill composite liners consisting of a geomembrane (GM) and a geosynthetic clay liner (GCL) or a GM and a compacted clay liner (CCL). The combined effect of leakage through GM defects, diffusion in GM and the underlying soil liners, and degradation in soil liners were considered. Steady state analytical solutions were provided for the proposed mathematical models, which consider the different combinations of advection, diffusion, and degradation. The analytical solutions of the time lag for contaminant transport in the composite liners were also derived. The performance of GM/GCL and GM/CCL was analyzed. For GM/GCL, the bottom flux can be reduced by a factor of 4 when the leachate head decreases from 10 to 0.3 m. The influence of degradation can be ignored for GM/GCL. For GM/CCL, when the leachate head decreases from 10 to 0.3 m, the bottom flux decreases by a factor of 2-4. Leachate head has greater influence on bottom flux in case of larger degradation rate (e.g., half-life = 1 year) compared to the case with lower degradation rate (e.g., half-life = 10 years). As contaminant half-life in soil liner decreases from 10 to 1 year, bottom flux decreases by approximately 2.7 magnitudes of orders. It is indicated that degradation may have greater influence on time lag of composite liner than leachate head. As leachate head increases from zero to 10 m, time lag for GM/CCL can be reduced by 5-6 years. Time lag for the same composite liner can be reduced by 10-11 years as contaminant half-life decreases from 10 to 1 year. Reducing leachate head acting on composite liners and increasing the degradation capacity of the soil liner would be the effective methods to improve the performance of the composite liners. The proposed analytical solutions are relatively simple and can be used for preliminary design and performance assessment of composite liners.

  18. Variation of crack intensity factor in three compacted clay liners exposed to annual cycle of atmospheric conditions with and without geotextile cover.

    PubMed

    Safari, E; Jalili Ghazizade, M; Abduli, M A; Gatmiri, B

    2014-08-01

    Performance of compacted clay liners commonly used as landfill barrier systems can be subject to decline in terms of hydraulic conductivity if left exposed to atmospheric conditions for an extended period of time prior to placement of overlaying layers. The resulting desiccation cracking can lead to increased hydraulic conductivity. Desiccation crack intensity was studied for three clayey soils commonly used for construction of landfill barrier system in a relatively large scale test setup exposed to real time atmospheric conditions over a complete annual cycle. A white separator geotextile cover was presumed to be capable of reducing the intensity of desiccation cracking through absorbing and maintaining higher amounts of moisture and reducing the temperature of the soil surface in comparison to a directly exposed soil surface. Desiccation cracking was monitored using a digital imaging technique for three compacted clay liners in two sets, one open to air and the second covered with the white geotextile. Crack intensity factor approached a relatively stable phase after certain cycles corresponding to atmospheric dry wet cycles. The results indicated that the white separator geotextile was capable of reducing the crack intensity factor by 37.4-45.9% throughout the experiment including the cyclic phase of desiccation cracking. During the stable phase, the maximum reduction in crack intensity factor of 90.4% as a result of applying geotextile cover was observed for the soil with the lowest plastic index and clay content and therefore the lowest magnitude of crack intensity factor. The other two soils with similar clay content but different plastic index showed 23.6% and 52.2% reductions in crack intensity factor after cyclic phase when covered with geotextile.

  19. An analytical model for solute transport through a GCL-based two-layered liner considering biodegradation.

    PubMed

    Guan, C; Xie, H J; Wang, Y Z; Chen, Y M; Jiang, Y S; Tang, X W

    2014-01-01

    An analytical model for solute advection and dispersion in a two-layered liner consisting of a geosynthetic clay liner (GCL) and a soil liner (SL) considering the effect of biodegradation was proposed. The analytical solution was derived by Laplace transformation and was validated over a range of parameters using the finite-layer method based software Pollute v7.0. Results show that if the half-life of the solute in GCL is larger than 1 year, the degradation in GCL can be neglected for solute transport in GCL/SL. When the half-life of GCL is less than 1 year, neglecting the effect of degradation in GCL on solute migration will result in a large difference of relative base concentration of GCL/SL (e.g., 32% for the case with half-life of 0.01 year). The 100-year solute base concentration can be reduced by a factor of 2.2 when the hydraulic conductivity of the SL was reduced by an order of magnitude. The 100-year base concentration was reduced by a factor of 155 when the half life of the contaminant in the SL was reduced by an order of magnitude. The effect of degradation is more important in approving the groundwater protection level than the hydraulic conductivity. The analytical solution can be used for experimental data fitting, verification of complicated numerical models and preliminary design of landfill liner systems.

  20. Frost effects on soil liner systems results of a research project

    SciTech Connect

    Erickson, A.E.; Chamberlain, E.J.; Benson, C.H.

    1995-12-31

    A research study was completed on the impact of frost action (freeze-thaw) on compacted clay liners, sand-bentonite liners, and geosynthetic clay liners (GCLs) under field and laboratory conditions. The goal of the research discussed in this paper was to improve understanding of the effect of freeze-thaw on these parts of liner systems so that design and construction could be improved. The U.S. Army Corps Cold Regions Research Engineering Laboratory (CRREL), CH2M HILL, Inc., and a team of industrial partners joined together in a cooperative effort to fund and complete this study under the U.S. Army Corps Construction Productivity Advancement Research (CPAR) program. IN 1992 and 1993, five large-scale compacted-soil test pads, and nine GCL test pans were constructed at WMX, Inc.`s Parkview Landfill in Milwaukee, Wisconsin. Two of the large-scale test pads were constructed of a low-plasticity clay, two were of a medium-plasticity clay, and one was a sand-bentonite mixture manufactured in a mobile mixer onsite. Three different GCL products were used in the GCL test pans. All of these materials were tested in the field for at least one winter; in the CRREL laboratory in Hanover, New Hampshire; and at the University of Wisconsin-Madison. Results of these tests indicate that the hydraulic conductivity of compacted clay increases significantly in the field after one winter of freezing. In laboratory testing, the use of thin-walled shelby tubes changes the clay structure and masks the effect of freeze-thaw. These tests indicated that the detrimental effects of freeze-thaw were reversed by increasing confining pressure. The hydraulic conductivity of the sand-bentonite test pad was found to be below 1x10{sup {minus}8} cm/s after two winter seasons. The GCLs showed no increase in hydraulic conductivity from freeze-thaw action. However, the field test results raised questions that need to be resolved.

  1. Modeling sorption and diffusion of organic sorbate in hexadecyltrimethylammonium-modified clay nanopores - a molecular dynamics simulation study.

    PubMed

    Zhao, Qian; Burns, Susan E

    2013-03-19

    Organoclays are highly sorptive engineered materials that can be used as amendments in barrier systems or geosynthetic liners. The performance of confining and isolating the nonpolar organic contaminants by those barrier/lining systems is essentially controlled by the process of organic contaminant mass transport in nanopores of organoclays. In this article, we use molecular dynamics (MD) simulations to study the sorption and diffusion of organic sorbates in interlayers of sodium montmorillonite and hexadecyltrimethylammonium (HDTMA(+))-modified montmorillonite clays. Simulated system consisted of the clay framework, interlayer organic cation, water, and organic sorbate. Their interactions were addressed by the combined force field of ClayFF, constant-valence force field, and SPC water model. Simulation results indicated that in HDTMA coated clay nanopores, diffusion of nonpolar species benzene was slowed because they were subjected to influence of both the pore wall and the HDTMA surfactant. This suggested the nonpolar organic compound diffusion in organophilic clays can be affected by molecular size of diffusive species, clay pore size, and organic surfactant loading. Additionally, a model that connected the diffusion rate of organic compounds in the bulk organoclay matrix with macropores and nanopores was established. The impact of intercalated organic cations on the diffusion dominated mass transport of organic compounds yielded insight into the prediction of the apparent diffusion behavior of organic compounds in organic-modified clays.

  2. Modeling of geosynthetic reinforced capping systems

    SciTech Connect

    Viswanadham, B.V.S.; Koenig, D.; Jessberger, H.L.

    1997-12-31

    The investigation deals with the influence of a geosynthetic reinforcement on the deformation behavior and sealing efficiency of the reinforced mineral sealing layer at the onset of non-uniform settlements. The research program is mainly concentrated in studying the influence of reinforcement inclusion in restraining cracks and crack propagation due to soil-geosynthetic bond efficiency. Centrifuge model tests are conducted in the 500 gt capacity balanced beam Bochum geotechnical Centrifuge (Z1) simulating a differential deformation of a mineral sealing layer of a landfill with the help of trap-door arrangement. By comparing the performance of the deformed mineral sealing layer with and without geogrid, the reinforcement ability of the geogrid in controlling the crack propagation and permeability of the mineral swing layer is evaluated.

  3. Improving Rutting Resistance of Pavement Structures Using Geosynthetics: An Overview

    PubMed Central

    Karim, Mohamed Rehan; Khodaii, Ali; Almasi, Mohammad Hadi

    2014-01-01

    A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting). PMID:24526919

  4. Application and analysis of anchored geosynthetic systems for stabilization of abandoned mine land slopes

    SciTech Connect

    Vitton, S.J.; Whitman, F.; Liang, R.Y.; Harris, W.W.

    1996-12-31

    An anchored geosynthetic system (AGS) was used in the remediation of a landslide associated with an abandoned coal mine located near Hindman, Kentucky. In concept, AGS is a system that provides in-situ stabilization of soil slopes by combining a surface-deployed geosynthetic with an anchoring system of driven reinforcing rods similar to soil nailing. Installation of the system of driven reinforcing rods similar to soil nailing. Installation of the system involves tensioning a geosynthetic over a slope`s surface by driving anchors through the geosynthetic at a given spacing and distance. By tensioning the geosynthetic over the slope`s surface, a compressive load is applied to the slope. Benefits of AGS are described to include the following: (1) increase soil strength due to soil compression including increased compressive loading on potential failure surfaces, (2) soil reinforcement through soil nailing, (3), halt of soil creep, (4) erosion control, and (5) long term soil consolidation. Following installation of the AGS and one year of monitoring, it was found that the anchored geosynthetic system only provided some of the reported benefits and in general did not function as an active stabilization system. This was due in part to the inability of the system to provide and maintain loading on the geosynthetic. The geosynthetic, however, did tension when slope movement occurred and prevented the slope from failing. Thus, the system functioned more as a passive restraint system and appeared to function well over the monitoring period.

  5. USER'S GUIDE TO GEOSYNTHETIC MODELING SYSTEM: GM SYSTEM VERSION 1.1

    EPA Science Inventory

    The document is a user manual for the Geosynthetic Modeling System. The menu-driven analytical system performs design calculations for 28 different landfill design applications that incorporate geosynthetic materials. The results of each set of design calculations are compared wi...

  6. 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.

  7. 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.

  8. Seismic performance of geosynthetic-soil retaining wall structures

    NASA Astrophysics Data System (ADS)

    Zarnani, Saman

    Vertical inclusions of expanded polystyrene (EPS) placed behind rigid retaining walls were investigated as geofoam seismic buffers to reduce earthquake-induced loads. A numerical model was developed using the program FLAC and the model validated against 1-g shaking table test results of EPS geofoam seismic buffer models. Two constitutive models for the component materials were examined: elastic-perfectly plastic with Mohr-Coulomb (M-C) failure criterion and non-linear hysteresis damping model with equivalent linear method (ELM) approach. It was judged that the M-C model was sufficiently accurate for practical purposes. The mechanical property of interest to attenuate dynamic loads using a seismic buffer was the buffer stiffness defined as K = E/t (E = buffer elastic modulus, t = buffer thickness). For the range of parameters investigated in this study, K ≤50 MN/m3 was observed to be the practical range for the optimal design of these systems. Parametric numerical analyses were performed to generate design charts that can be used for the preliminary design of these systems. A new high capacity shaking table facility was constructed at RMC that can be used to study the seismic performance of earth structures. Reduced-scale models of geosynthetic reinforced soil (GRS) walls were built on this shaking table and then subjected to simulated earthquake loading conditions. In some shaking table tests, combined use of EPS geofoam and horizontal geosynthetic reinforcement layers was investigated. Numerical models were developed using program FLAC together with ELM and M-C constitutive models. Physical and numerical results were compared against predicted values using analysis methods found in the journal literature and in current North American design guidelines. The comparison shows that current Mononobe-Okabe (M-O) based analysis methods could not consistently satisfactorily predict measured reinforcement connection load distributions at all elevations under both static

  9. Analysis on the Long Term Effect of Trial Test Road Constructed on Batu Pahat Soft Clay (BPSC) at Recess UTHM

    NASA Astrophysics Data System (ADS)

    Idrus, M. M. M.; Edayu, A. E.; Adnan, Z.; Ismail, B.

    2016-07-01

    The reinforcement used in soil for construction of roads on the soft clay is very important as it will determine the level of service of the road after it was built. Damage or defects on the road surface to be an indicator of the level of the road has dropped and shows the deformation of the road. For this research, an analysis has carried out on the long-term effect of trial test road constructed on Batu Pahat Soft Clay (BPSC) at RECESS UTHM. Through this research, the reinforcement using Rawell Geosynthetic Clay Liner (RGCL) was the best with the stability is 14964 N, a low flow is 2.69mm, stiffness modulus is 1766 MPa, the peak load is 739.4 N and a lower horizontal deformation which is 1.71 µm compared Woven Geotextile section and section without geotextile [1] [9]. In terms of deformation can be seen clearly from physical observations that section without geotextile suffered significant damage than others. Settlement of road can also be analyzed by a longitudinal section that plotted based on the result of leveling work. After that, settlements are more visible way on the right side of the road trial. Through lab tests conducted, it indicate that the coring samples obtained from sites of each section meets the specifications set by the Jabatan Kerja Raya (JKR) in terms of stability, flow and stiffness [1]. Through this study, a trial road built on soft soil can be used as a test site because of the uniqueness of these roads which has three different types of reinforcements.

  10. A Simplified Method for Analysis of Geosynthetic Reinforcement Used in Pile Supported Embankments

    PubMed Central

    Fei, Kang

    2014-01-01

    The inclusion of geosynthetic reinforcement in the piled embankment can help transfer loads to the piles and reduce total and differential settlements. In order to select the appropriate reinforcement material, the reasonable calculation of the deflection and tension is very important. Current design methods usually do not represent the true three-dimensional (3D) nature of the displacements, strains, and stresses of the geosynthetics, and the resulting error may be large and cannot be neglected in some cases. In this study, two- and three-dimensional finite element analyses were conducted to identify the behavior of geosynthetic reinforcement and investigate the accuracy of the assumptions made in the current design methods. Based on the numerical results, a new 3D deflected shape of the geosynthetic reinforcement was suggested, and then the corresponding governing equation was derived and solved based on the membrane theory. To investigate the validity of the proposed method, the predicted maximum deflection, deflection shape, and the developed tensile force of the geosynthetics have been compared with the experimental data collected from the literatures and finite element analysis results. PMID:25215318

  11. Monitoring the performance of geosynthetic materials within pavement systems using MEMS

    NASA Astrophysics Data System (ADS)

    Attoh-Okine, Nii O.; Ayenu-Prah, Albert Y.; Mensah, Stephen A.

    2005-05-01

    Geosynthetic materials have found useful applications when unbound aggregates have been placed on cohesive soil with very weak subgrade. They have also been successfully used in retarding reflective cracking in both flexible and composite pavements. There are many applications of geosynthetics in pavement engineering yet there is considerable lack of understanding in the behavior of the material. Geosynthetic materials exhibit very peculiar properties in the area of tensile strength and reinforcement. MEMS are miniature sensing or actuating devices that can interact with other environments (provided no adverse reaction occurs) to either obtain information or alter it. With remote query capability, it appears such devices can be embedded in pavement systems as testing and monitoring tools. The aim of this paper is to propose both field and laboratory methods for monitoring geotextile performance using MEMS.

  12. Hydraulic conductivity of landfill liners containing benzyltriethylammonium-bentonite

    USGS Publications Warehouse

    Smith, James A.; Franklin, Pamela M.; Jaffe, Peter R.

    1992-01-01

    Varying weight percentages of an Ottawa sand, benzyltriethylammonium-bentonite (BTEA-clay), Wyoming bentonite (Na-clay), and water were mixed uniformly and compacted to simulate sand-and-clay liners for waste-disposal facilities. The hydraulic conductivities of the compacted soil cores were measured in triplicate. The hydraulic conductivities of cores containing 92 percent sand and 8 percent BTEA-clay were about of 10-4 cm/s. The hydraulic conductivities of cores containing 92 percent sand and 8 percent Na-clay and of cores containing 88 percent sand, 8 percent Na-clay, and 4 percent BTEA-clay were about 10-8 cm/s.

  13. IN-SERVICE HYDRAULIC CONDUCTIVITY OF GCLS IN LANDFILL COVERS - LABORATORY AND FIELD STUDIES

    EPA Science Inventory

    Laboratory experiments using multi-species inorganic solutions (containing calcium and sodium) were conducted on specimens of a new geosynthetic clay liner (GCL) containing sodium bentonite to determine how cation exchange and desiccation affected the hydraulic conductivity. Calc...

  14. Ball clay

    USGS Publications Warehouse

    Virta, Robert L.

    2010-01-01

    The article reports on the global market performance of ball clay in 2009 and presents an outlook for its 2010 performance. Several companies mined ball call in the country including Old Hickey Clay Co., Kentucky-Tennessee Clay Co., and H.C. Spinks Clay Co. Information on the decline in ball clay imports and exports is also presented.

  15. 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.

  16. Clays, specialty

    USGS Publications Warehouse

    Virta, R.L.

    1998-01-01

    Part of a special section on the state of industrial minerals in 1997. The state of the specialty clay industry worldwide for 1997 is discussed. The specialty clays mined in the U.S. are ball clay, fuller's earth, bentonite, fire clay, and kaolin. Sales of specialty clays in the U.S. were around 17 Mt in 1997. Approximately 53 kt of specialty clays were imported.

  17. Development of reactive artificial liner using recycled materials. 2. Chemical transport properties.

    PubMed

    Chin, Johnnie Y; Asavanich, Pitch; Moon, Kyong-Whan; Park, Jae K

    2013-07-01

    Volatile organic compounds (VOCs) have so far been found to permeate through geomembranes within days and potentially pollute the surrounding groundwater if no sufficient depth of underlain soil barrier existed In order to cope with the fast breakthrough of VOCs through high-density polyethylene (HDPE) geomembrane in the composite liner system, a composite material made of recycled materials was proposed and its mechanical properties were analyzed in a previous study. This artificial liner was composed of crumb rubber, organo-clay, silica fume and epoxy binder together with an environmentally-friendly solvent recycled from paper pulping, and dimethyl sulfoxide as a plasticizer. In this study, the new artificial liner and a typical HDPE geomembrane were tested to compare their abilities to mitigate the movement of VOCs, specifically partition coefficient, diffusion coefficient and mass fluxes. It was found that this new artificial liner had 2-3 orders of magnitude less VOC mass flux than the HDPE geomembrane. The new artificial liner is thought to have a great potential for containing VOCs, even with a thickness of 2.5 cm, and as a substitute for the clay liner. The cost of installing the artificial liner was estimated to be $13.78/m(2). This is lower than the current geomembrane-related price of $19.70-26.91/m(2). The new liner might give a new perspective in future liner design and alleviate the concerning issue of groundwater pollution caused by landfill leachate, which might contain highly mobile VOCs.

  18. 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.

  19. Combustor liner support assembly

    NASA Technical Reports Server (NTRS)

    Halila, Ely E. (Inventor)

    1994-01-01

    A support assembly for a gas turbine engine combustor includes an annular frame having a plurality of circumferentially spaced apart tenons, and an annular combustor liner disposed coaxially with the frame and including a plurality of circumferentially spaced apart tenons circumferentially adjoining respective ones of the frame tenons for radially and tangentially supporting the liner to the frame while allowing unrestrained differential thermal radial movement therebetween.

  20. Clay Play

    ERIC Educational Resources Information Center

    Rogers, Liz; Steffan, Dana

    2009-01-01

    This article describes how to use clay as a potential material for young children to explore. As teachers, the authors find that their dialogue about the potential of clay as a learning medium raises many questions: (1) What makes clay so enticing? (2) Why are teachers noticing different play and conversation around the clay table as compared to…

  1. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2001-01-01

    Part of the 2000 annual review of the industrial minerals sector. A general overview of the ball clay industry is provided. In 2000, sales of ball clay reached record levels, with sanitary ware and tile applications accounting for the largest sales. Ball clay production, consumption, prices, foreign trade, and industry news are summarized. The outlook for the ball clay industry is also outlined.

  2. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2007-01-01

    The article offers information on ball clay. Among the companies that mine ball clay in the U.S. are H.C. Spinks Clay, Kentucky-Tennessee Clay and Old Hickory Clay. In 2006, an estimated 1.2 million tons of the mineral was sold or used domestically and exported. Forty-percent of the total sales is accounted for ceramic floor and wall tile followed by sanitaryware and miscellaneous ceramics. Its average value was $ 45 per ton in 2006.

  3. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2011-01-01

    The article discusses the latest developments in the global ball clay mining industry, particularly in the U.S., as of June 2011. It cites several firms that are involved in ball clay mining in the U.S., including HC Spins Clay Co. Inc., the Imerys Group and Old Hickory Clay Co. Among the products made from ball clay are ceramic tiles, sanitaryware, as well as fillers, extenders and binders.

  4. Strain gage installation and survivability on geosynthetics used in flexible pavements

    NASA Astrophysics Data System (ADS)

    Brooks, Jeremy A.

    The use of foil type strain gages on geosynthetics is poorly documented. In addition, very few individuals are versed in proper installation techniques or calibration methods. Due to the limited number of knowledgeable technicians there is no information regarding the susceptibility of theses gages to errors in installation by inexperienced installers. Also lacking in the documentation related to the use of foil type strain gages on geosynthetics is the survivability of the gages in field conditions. This research documented procedures for installation, calibration, and survivability used by the project team to instruments a full scale field installation in Marked Tree, AR. This research also addressed sensitivity to installation errors on both geotextile and geogrid. To document the process of gage installation an experienced technician, Mr. Joe Ables, formerly of the UASCE Waterways Experiment Station, was consulted. His techniques were combined with those discovered in related literature and those developed by the research team to develop processes that were adaptable to multiple gage geometries and parent geosynthetics. These processes were described and documented in a step by step manner with accompanying photographs, which should allow virtually anyone with basic electronics knowledge to install these gages properly. Calibration of the various geosynthetic / strain gage combinations was completed using wide width tensile testing on multiple samples of each material. The tensile testing process was documented and analyzed using digital photography to analyze strain on the strain gage itself. Calibration factors for each geosynthtics used in the full scale field testing were developed. In addition, the process was thoroughly documented to allow future researchers to calibrate additional strain gage and geosynthetic combinations. The sensitivity of the strain gages to installation errors was analyzed using wide width tensile testing and digital photography to

  5. 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.

  6. Deformation Behaviors of Geosynthetic Reinforced Soil Walls on Shallow Weak Ground

    NASA Astrophysics Data System (ADS)

    Kim, You-Seong; Won, Myoung-Soo

    In this study, the fifteen-month behavior of two geosynthetic reinforced soil walls, which was constructed on the shallow weak ground, was measured and analyzed. The walls were backfilled with clayey soil obtained from the construction site nearby, and the safety factors obtained from general limit equilibrium analysis were less than 1.3 in both wall. To compare with the measured data from the real GRS walls and unreinforced soil mass, a series of finite element method (FEM) analyses on two field GRS walls and unreinforced soil mass were conducted. The FEM analysis results showed that failure plane of unreinforced soil mass was consistent with the Rankine active state, but failure plane did not occur in GRS walls. In addition, maximum horizontal displacements and shear strains in GRS walls were 50% smaller than those found in unreinforced soil mass. Modeling results such as the maximum horizontal displacements, horizontal pressure, and geosynthetic tensile strengths in GRS wall have a god agreement with the measured data. Based on this study, it could be concluded that geosynthetic reinforcement are effective to reduce the displacement of the wall face and/or the deformation of the backfill soil even if the mobilized tensile stress after construction is very small.

  7. Acoustic Liners for Turbine Engines

    NASA Technical Reports Server (NTRS)

    Jones, Michael G (Inventor); Grady, Joseph E (Inventor); Kiser, James D. (Inventor); Miller, Christopher (Inventor); Heidmann, James D. (Inventor)

    2016-01-01

    An improved acoustic liner for turbine engines is disclosed. The acoustic liner may include a straight cell section including a plurality of cells with straight chambers. The acoustic liner may also include a bent cell section including one or more cells that are bent to extend chamber length without increasing the overall height of the acoustic liner by the entire chamber length. In some cases, holes are placed between cell chambers in addition to bending the cells, or instead of bending the cells.

  8. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2013-01-01

    Four companies — H.C. Spinks Clay Co., Inc., Imerys, Old Hickory Clay Co. and Unimin Corp. — mined ball clay in five U.S. states in 2012. Production, on the basis of preliminary data, was 900 kt (992,000 st), with an estimated value of $42.3 million. This was a slight increase in tonnage from 886 kt (977,000 st), with a value of $40.9 million in 2011. Tennessee was the leading ball clay producing state, with 63 percent of domestic production, followed by Texas, Mississippi, Kentucky and Indiana. Reported ball clay production from Indiana probably was fire clay rather than ball clay. About 69 percent of total ball clay production was airfloat, 20 percent was crude and 11 percent was water-slurried.

  9. Fire clay

    USGS Publications Warehouse

    Virta, R.L.

    2011-01-01

    The article discusses the latest developments in the fire clay industry, particularly in the U.S., as of June 2011. It claims that the leading fire clay producer in the U.S. is the state of Missouri. The other major producers include California, Texas and Washington. It reports that the use of heavy clay products made of fire clay like brick, cement and lightweight aggregate has increased slightly in 2010.

  10. Clays, common

    USGS Publications Warehouse

    Virta, R.L.

    1998-01-01

    Part of a special section on the state of industrial minerals in 1997. The state of the common clay industry worldwide for 1997 is discussed. Sales of common clay in the U.S. increased from 26.2 Mt in 1996 to an estimated 26.5 Mt in 1997. The amount of common clay and shale used to produce structural clay products in 1997 was estimated at 13.8 Mt.

  11. Clay Houses

    ERIC Educational Resources Information Center

    Pedro, Cathy

    2011-01-01

    In this article, the author describes a project designed for fourth-graders that involves making clay relief sculptures of houses. Knowing the clay houses will become a family heirloom makes this lesson even more worth the time. It takes three classes to plan and form the clay, and another two to underglaze and glaze the final products.

  12. 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…

  13. 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.

  14. Fire clay

    USGS Publications Warehouse

    Virta, R.L.

    2013-01-01

    Four companies mined fire clay in three states in 2012. Production, based on a preliminary survey of the fire clay industry, was estimated to be 230 kt (254,000 st) valued at $6.98 million, an increase from 215 kt (237,000 st) valued at $6.15 million in 2011. Missouri was the leading producing state, followed by Colorado and Texas, in decreasing order by quantity. The number of companies mining fire clay declined in 2012 because several common clay producers that occasionally mine fire clay indicated that they did not do so in 2012.

  15. 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.

  16. Well liner running shoe

    SciTech Connect

    Bell, J.F.

    1994-01-11

    Wellbore liners are set with a running shoe comprising a cylindrical body, end cap, check valve and receiver member in assembly. The receiver member includes threads for receiving the coupling sleeve of a running tool, and retaining wickers for engagement with a cement plug or dart to retain the same permanently engaged with and blocking the flow of fluid through the running shoe. A running tool for use with the shoe includes a coupling sleeve which is retained on a support mandrel by a collar which is secured to the mandrel with a shear pin so that pressuring up the workstring, in the event of a stuck coupling sleeve, will permit retrieval of the main part of the running tool and the workstring. The interior parts of the running shoe are made of aluminum or plastic for easy drill-out to extend the wellbore beyond the end of the liner. 3 figs.

  17. Evaluation of oxidative behavior of polyolefin geosynthetics utilizing accelerated aging tests based on temperature and pressure

    NASA Astrophysics Data System (ADS)

    Li, Mengjia

    Polyolefin geosynthetics are susceptible to oxidation, which eventually leads to the reduction in their engineering properties. In the application of polyolefin geosynthetics, a major issue is an estimate of the materials durability (i.e. service lifetime) under various aging conditions. Antioxidant packages are added to the polyolefin products to extend the induction time, during which antioxidants are gradually depleted and polymer oxidation reactions are prevented. In this PhD study, an improved laboratory accelerating aging method under elevated and high pressure environments was applied to evaluate the combined effect of temperature and pressure on the depletion of the antioxidants and the oxidation of polymers. Four types of commercial polyolefn geosynthetic materials selected for aging tests included HDPE geogrid, polypropylene woven and nonwoven geotextiles. A total of 33 different temperature/pressure aging conditions were used, with the incubation duration up to 24 months. The applied oven temperature ranged from 35°C to 105°C and the partial oxygen pressure ranged from 0.005 MPa to 6.3 MPa. Using the Oxidative Induction Time (OIT) test, the antioxidant depletion, which is correlated to the decrease of the OIT value, was found to follow apparent first-order decay. The OIT data also showed that, the antioxidant depletion rate increased with temperature according to the Arrhenius equation, while under constant temperatures, the rate increased exponentially with the partial pressure of oxygen. A modified Arrhenius model was developed to fit the antioxidant depletion rate as a function of temperature and pressure and to predict the antioxidant lifetime under various field conditions. This study has developed new temperature/pressure incubation aging test method with lifetime prediction models. Using this new technique, the antioxidant lifetime prediction results are close to regular temperature aging data while the aging duration can be reduced considerably

  18. Fire clay

    USGS Publications Warehouse

    Virta, R.L.

    2006-01-01

    In 2005, six companies mined fire clay in Missouri, Ohio and South Carolina. Production was estimate to be 300 kt with a value of $8.3 million. Missouri was the leading producer state followed by Ohio and South Carolina. For the third consecutive year, sales and use of fire clays have been relatively unchanged. For the next few years, sales of fire clay is forecasted to remain around 300 kt/a.

  19. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2000-01-01

    Part of the 1999 Industrial Minerals Review. The state of the ball clay industry in 1999 is presented. Record highs in the sales and use of ball clay were attained in 1999 due to the continued strength of the U.S. economy. U.S. production was estimated at 1.25 million st for the year, with more than half of that amount mined in Tennessee. Details of the consumption, price, imports, and exports of ball clay in 1999 and the outlook for ball clay over the next few years are provided.

  20. LINER FOR EXTRUSION BILLET CONTAINERS

    DTIC Science & Technology

    Shrink-fit assembly device for buildup of ceramic-coated liner and sleeve assemblies was tested and modified to develop desired temperatures and...preliminary evaluation of suitability for extrusion liner use. Procedures were developed for welding short, hollow ceramic cylinders of high-strength metal...carbides and borides to form a ceramic extrusion liner of suitable length. Disassembly tooling for rapid separation of shrink-fitted sleeves from a worn

  1. 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.

  2. 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

  3. Leakage performance of the GM + CCL liner system for the MSW landfill.

    PubMed

    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.

  4. 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.

  5. LINER FOR EXTRUSION BILLET CONTAINERS

    DTIC Science & Technology

    Rokide-process alumina and zirconia coatings and a Udimet 700 superalloy liner were evaluated by extrusion of 3 1/2-in. billets of Inconel 713C...One coating did with stand extrusion at 3450 F without apparent wear. The Udimet 700 liner did not show wear at 2000 F, but did react with the TZM

  6. Space sail liner

    NASA Astrophysics Data System (ADS)

    Lukyanov, A. V.

    1983-09-01

    Space vehicles, fit to ply between space objects and to transport hundreds of tons, will be necessary for research expeditions to planets and for asteroids materials supply to future space settlements, factories and satellite solar power stations. The means of creating such sail "liners" are discussed in the paper. The liner's solar sail area is dozens to hundreds of km 2. The sail is produced by combining in line small standard controlled units assembled or deployed in space. The equations of motion and sail control are considered. It is shown how superlight rotating reflectors, investigated by the author before, could be used to construct a sail. Another construction may be obtained by means of connecting stiff framework square reflectors and can be easily realized. Using deployable tubes made of composite straps will essentially lighten the square unit framework. Commercially available 4-μm thick aluminized mylar film and considerably thinner film may be used, and its mass will be most of the sail mass. Assembling of such a sail may be carried out on the orbiting assembling station.

  7. Fire clay

    USGS Publications Warehouse

    Virta, R.L.

    2012-01-01

    Five companies mined fire clay in four states in 2011. Production, based on a preliminary survey of the fire clay industry, was estimated to be 240 kt (265,000 st), valued at $7.68 million, an increase from 216 kt (238,000 st), valued at $6.12 million in 2010. Missouri was the leading producing state, followed by Texas, Washington and Ohio, in decreasing order by quantity.

  8. Polypropylene Fiber Amendments to Alleviate Initiation and Evolution of Desiccation Cracks in Bentonite Liners

    NASA Astrophysics Data System (ADS)

    Tuller, M.; Gebrenegus, T. B.

    2009-12-01

    Sodium saturated bentonite is a major constituent of compacted and geosynthetic liners and covers for hydraulic isolation of hazardous waste, playing a crucial role in protecting groundwater and other environmental resources from harmful landfill leachates. Due to favorable hydraulic properties (i.e., low permeability), large surface area and associated adsorption capacity for particular contaminants, and relative abundance and low cost, bentonite is the material of choice in many modern waste containment systems. However, long-term interactions between bentonite and waste leachate and exposure of bentonite to desiccative conditions may significantly deteriorate liner or cover performance and ultimately lead to failure of containment systems. In the presented study, the potential usefulness of polypropylene fiber amendments for preventing initiation and evolution of desiccation cracks, while maintaining acceptably low permeability under saturated conditions was investigated. Well-controlled desiccation experiments were conducted using initially saturated bentonite-sand mixtures that contained varying amounts of polypropylene fibers. Initiation and evolution of surface cracks were observed by means of X-Ray Computed Tomography (CT). Advanced image analysis techniques were employed to characterize and quantify 2-D and 3-D features of the evolving crack networks. Potential negative effects of employed additives on saturated hydraulic conductivity were determined with fully-automated Flexible Wall Permeametry (FWP).

  9. 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.

  10. Clay Minerals

    SciTech Connect

    Mueller, Karl T.; Sanders, Rebecca L.; Washton, Nancy M.

    2014-03-14

    Clay minerals are important components of the environment and are involved or implicated in processes such as the uptake of pollutants and the release of nutrients and as potential platforms for a number of chemical reactions. Owing to their small particle sizes (typically, on the order of microns or smaller) and mixing with a variety of other minerals and soil components, advanced characterization methods are needed to study their structures, dynamics, and reactivities. In this article, we describe the use of solid-state NMR methods to characterize the structures and chemistries of clay minerals. Early one-pulse magic-angle spinning (MAS) NMR studies of 27Al and 29Si have now been enhanced and extended with new studies utilizing advanced methodologies (such as Multiple Quantum MAS) as well as studies of less-sensitive nuclei. In additional work, the issue of reactivity of clay minerals has been addressed, including studies of reactive surface area in the environment. Utilizations of NMR-sensitive nuclides within the clay minerals themselves, and in molecules that react with specific sites on the clay mineral surfaces, have aided in understanding the reactivity of these complex aluminosilicate systems.

  11. Ball clay

    USGS Publications Warehouse

    Virta, R.L.

    2012-01-01

    Four companies — H.C. Spinks Clay Co., Inc., Imerys Group, Old Hickory Clay Co., and Unimin Corp. — mined ball clay in four states in 2011. Production, on the basis of preliminary data, was 940 kt (1.04 million st) with an estimated value of $44.2 million. This is a 3-percent increase in tonnage from 912 kt (1.01 million st) with a value of $41.3 million that was produced in 2010. Tennessee was the leading producing state with 63 percent of domestic production, followed by Texas, Mississippi and Kentucky. About 69 percent of production was airfloat, 20 percent was crude and 11 percent was water-slurried.

  12. Machine Gun Liner Bond Strength

    DTIC Science & Technology

    2007-08-01

    investigation does not constitute a complete analysis of liner failures in the M2 machine gun. The fact that two different liner-failure modes were...An order-of-magnitude estimate can be made of the bond strength in this case using a standard elastic analysis and some reasonable assumptions... analysis of the forces on the machine gun bullet, it was found that the measured bond strength was adequate to resist the reaction forces produced when

  13. FGD liner experiments with wetlands

    SciTech Connect

    Mitsch, W.J.; Ahn, C.; Wolfe, W.E.

    1999-07-01

    The construction of artificial wetlands for wastewater treatment often requires impermeable liners not only to protect groundwater resources but also to ensure that there is adequate water in the wetland to support appropriate aquatic life, particularly wetland vegetation. Liners or relatively impervious site soils are very important to the success of constructed treatment wetlands in areas where ground water levels are typically close to the ground surface. This study, carried out at the Olentangy River Wetland Research Park, investigated the use of FGD material from sulfur scrubbers as a possible liner material for constructed wetlands. While several studies have investigated the use of FGD material to line ponds, no studies have investigated the use of this material as a liner for constructed wetlands. They used experimental mesocosms to see the effect of FGD liner materials in constructed wetlands on water quality and on wetland plant growth. This paper presents the results of nutrient analyses and physicochemical investigation of leachate and surface outflow water samples collected from the mesocosms. Plant growth and biomass of wetland vegetation are also included in this paper. First two year results are reported by Ahn et al. (1998, 1999). The overall goal of this study is the identification of advantages and disadvantages of using FGD by-product as an artificial liner in constructed wetlands.

  14. Field trip guidebook on environmental impact of clays along the upper Texas coast

    NASA Technical Reports Server (NTRS)

    Garcia, Theron D.; Ming, Douglas W.; Tuck, Lisa Kay

    1991-01-01

    The field trip was prepared to provide an opportunity to see first hand some the environmental hazards associated with clays in the Houston, Texas area. Because of the very high clay content in area soils and underlying Beaumont Formation clay, Houston is a fitting location to host the Clay Mineral Society. Examinations were made of (1) expansive soils, (2) subsidence and surface faulting, and (3) a landfill located southeast of Houston at the Gulf Coast Waste Disposal Authority where clay is part of the liner material.

  15. Clay for Little Fingers.

    ERIC Educational Resources Information Center

    Koster, Joan Bouza

    1999-01-01

    Discusses the renewed interest in clay as a modeling compound in early childhood programs; describes the nature of clay and presents a working vocabulary. Suggests methods of working with clay, including introducing clay to children, discovering its uses, clean up, firing clay, and finishing baked clay. Includes activity suggestions and…

  16. Fire clay

    USGS Publications Warehouse

    Virta, R.L.

    2004-01-01

    Seven companies mined fire clay in four states during 2003. From 1984 to 1992, production declined to 383 kt (422,000 st) from a high of 1.04 Mt (1.14 million st) as markets for clay-based refractories declined. Since 1992, production levels have been erratic, ranging from 383 kt (422,000 st) in 1992 and 2001 to 583 kt (642,000 st) in 1995. Production in 2003, based on preliminary data, was estimated to be around 450 kt (496,000 st) with a value of about $10.5 million. This was about the same as in 2002. Missouri remained the leading producer state, followed by South Carolina, Ohio and California.

  17. Surface treatment using metal foil liner

    NASA Technical Reports Server (NTRS)

    Garvey, Ray

    1989-01-01

    A metal foil liner can be used to seal large area surfaces. Characteristics of the two-layer foil liner are discussed. Micrographs for foil-to-foil, foil-to-composite, visible seams, and hidden seams are examined.

  18. Evaluation of Comfort Liners for Pilot Helmets.

    DTIC Science & Technology

    1994-09-01

    coated open-cell foam system called a Thermoformed Liner (TFL) by Kaiser Electronics. Coefficient of friction, compression and creep data are generated on each of the II helmet comfort liner materials.

  19. Investigation of degree of saturation in landfill liners using electrical resistivity imaging.

    PubMed

    Kibria, Golam; Hossain, Md Sahadat

    2015-05-01

    During construction of compacted clay liners and evapotranspiration (ET) covers, quality control involves laboratory and field tests in individual lifts. However, the available methods may be inadequate to determine non-uniform compaction conditions, poor bonding of lifts, and/or variable soil composition. Moreover, the applicability of the available methods is restricted, in many instances, when spatial variability of the subsurface is expected. Resistivity Imaging (RI) is a geophysical method employed to investigate a large area in a rapid and non-destructive way. High resistivity of clay liner soil is an indication of a low degree of saturation, high air-filled voids, and poor lift bonding. To utilize RI as a quality control tool in a landfill liner, it is important to determine the saturation condition of the compacted soils because compaction and permeability of liner soil are functions of degrees of saturation. The objective of the present study is to evaluate the degree of saturation of a municipal solid waste (MSW) landfill liner, using RI. Electrical resistivity tests were performed in the laboratory, at varied moisture contents and dry unit weights, on four types of soil samples, i.e., highly plastic clay (CH), low plastic clay (CL), Ca-bentonite, and kaolinite. According to the experimental results, electrical resistivity of the specimens decreased as much as 15.3 times of initial value with increase in the degrees of saturation from 23% to 100%. In addition, cation exchange capacity (CEC) substantially affected resistivity. A multiple linear regression (MLR) model was developed to correlate electrical resistivity with degree of saturation and CEC using experimental results. Additionally, RI tests were conducted on compacted clay liners to determine the degrees of saturation, and predicted degrees of saturation were compared with the in-situ density tests. The study results indicated that the developed model can be utilized for liner soils having CEC

  20. An Evaluation of Long-Term Performance of Liner Systems for Low-Level Waste Disposal Facilities

    SciTech Connect

    Arthur S. Rood; Annette L. Schafer; A. Jeffrey Sondrup

    2011-03-01

    Traditional liner systems consisting of a geosynthetic membrane underlying a waste disposal facility coupled with a leachate collection system have been proposed as a means of containing releases of low-level radioactive waste within the confines of the disposal facility and thereby eliminating migration of radionuclides into the vadose zone and groundwater. However, this type of hydraulic containment liner system is only effective as long as the leachate collection system remains functional or an overlying cover limits the total infiltration to the volumetric pore space of the disposal system. If either the leachate collection system fails, or the overlying cover becomes less effective during the 1,000’s of years of facility lifetime, the liner may fill with water and release contaminated water in a preferential or focused manner. If the height of the liner extends above the waste, the waste will become submerged which could increase the release rate and concentration of the leachate. If the liner extends near land surface, there is the potential for contamination reaching land surface creating a direct exposure pathway. Alternative protective liner systems can be engineered that eliminate radionuclide releases to the vadose zone during operations and minimizing long term migration of radionuclides from the disposal facility into the vadose zone and aquifer. Non-traditional systems include waste containerization in steel or composite materials. This type of system would promote drainage of clean infiltrating water through the facility without contacting the waste. Other alternatives include geochemical barriers designed to transmit water while adsorbing radionuclides beneath the facility. Facility performance for a hypothetical disposal facility has been compared for the hydraulic and steel containerization liner alternatives. Results were compared in terms of meeting the DOE Order 435.1 low-level waste performance objective of 25 mrem/yr all-pathways dose

  1. 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.

  2. High Temperature Acoustic Liner Technology

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Jones, Michael G.; Posey, Joe W.

    1999-01-01

    This paper describes work currently in progress at Langley on liner concepts that employ structures that may be suitable for broadband exhaust noise attenuation in high speed flow environments and at elevated temperatures characteristic of HSCT applications. Because such liners will need to provide about 10 dB suppression over a 2 to 3 octave frequency range, conventional single-degree-of-freedom resonant structures will not suffice. Bulk absorbers have the needed broadband absorption characteristic; however, at lower frequencies they tend to be inefficient.

  3. A laboratory study on migration of K+ in a two-layer landfill liner system.

    PubMed

    Du, Yan Jun; Hayashi, Shigenori

    2005-10-01

    Contaminant transport through the clay liner and the underIying secondary leachate drain layer (SLDL) in landfills was studied through a laboratory test, and analysis method on the transport of K+ in a two-layer soil system. The soils used for this study were Ariake clay and the underlying layer, Shirasu soil from the Kyushu region of Japan, representing the clay liner material and SLDL material, respectively. The effective diffusion coefficients (De) of the selected target chemical species, potassium (K+) for the Ariake clay and Shirasu soil were back-calculated using a computer program, and it was found that values of De derived from this study were consistent with those previously published. The hypothesis that the mechanical dispersion process can be negligible has been proved to be reasonable based on both the observation that the predicted values fit the experimental data and the analyses of two dimensionless parameters. Parametric analysis showed the transport of K+ through the soils is controlled by advection-diffusion rather than diffusion only, whereas at low Darcy velocity (i.e. < or = 10(-9) m s(-1)), transport of K+ would be controlled by diffusion. The test results and parametric analysis may be applied in design of landfill liners and SLDLs, particularly in coastal areas.

  4. Geotechnical characterization of mined clay from Appalachian Ohio: challenges and implications for the clay mining industry.

    PubMed

    Moran, Anthony R; Hettiarachchi, Hiroshan

    2011-07-01

    Clayey soil found in coal mines in Appalachian Ohio is often sold to landfills for constructing Recompacted Soil Liners (RSL) in landfills. Since clayey soils possess low hydraulic conductivity, the suitability of mined clay for RSL in Ohio is first assessed by determining its clay content. When soil samples are tested in a laboratory, the same engineering properties are typically expected for the soils originated from the same source, provided that the testing techniques applied are standard, but mined clay from Appalachian Ohio has shown drastic differences in particle size distribution depending on the sampling and/or laboratory processing methods. Sometimes more than a 10 percent decrease in the clay content is observed in the samples collected at the stockpiles, compared to those collected through reverse circulation drilling. This discrepancy poses a challenge to geotechnical engineers who work on the prequalification process of RSL material as it can result in misleading estimates of the hydraulic conductivity of the samples. This paper describes a laboratory investigation conducted on mined clay from Appalachian Ohio to determine how and why the standard sampling and/or processing methods can affect the grain-size distributions. The variation in the clay content was determined to be due to heavy concentrations of shale fragments in the clayey soils. It was also concluded that, in order to obtain reliable grain size distributions from the samples collected at a stockpile of mined clay, the material needs to be processed using a soil grinder. Otherwise, the samples should be collected through drilling.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. A waterproof cast liner earns high marks.

    PubMed

    Selesnick, H; Griffiths, G

    1997-09-01

    Nondisplaced and stable fractures or severe sprains may be casted using fiberglass and a waterproof liner. Application of the liner is illustrated and described here. Allergic reactions, liner bulkiness, cast application and removal, and cost of materials have not proven to be problems. Among 337 patients fitted with this liner, odor, itching, and difficulties with drying were minimal, even though patients swam, bathed, or received hydrotherapy. Minor skin complications occurred in 5.9% of patients. Physician and patient satisfaction with the liner was high.

  10. 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.

  11. Clay: The Forgotten Art.

    ERIC Educational Resources Information Center

    Martin, Doris Marie

    1995-01-01

    Discusses the tactile and kinesthetic areas of learning children experience when using clay. Includes practical tips for using and storing clay for preschool use and notes the differences between potters' clay and play dough. (HTH)

  12. 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.

  13. Segmented Liner to Control Mode Scattering

    NASA Technical Reports Server (NTRS)

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

    2013-01-01

    The acoustic performance of duct liners can be improved by segmenting the treatment. In a segmented liner treatment, one stage of liner reduces the target sound and scatters energy into other acoustic modes, which are attenuated by a subsequent stage. The Curved Duct Test Rig is an experimental facility in which sound incident on the liner can be generated in a specific mode and the scatter of energy into other modes can be quantified. A series of experiments is performed in which the baseline configuration is asymmetric, that is, a liner is on one side wall of the test duct and the wall opposite is acoustically hard. Segmented liner treatment is achieved by progressively replacing sections of the hard wall opposite with liner in the axial direction, from 25% of the wall surface to 100%. It is found that the energy scatter from the (0,0) to the (0,1) mode reduces as the percentage of opposite wall treatment increases, and the frequency of peak attenuation shifts toward higher frequency. Similar results are found when the incident mode is of order (0,1) and scatter is into the (0,0) mode. The propagation code CDUCT-LaRC is used to predict the effect of liner segmenting on liner performance. The computational results show energy scatter and the effect of liner segmentation that agrees with the experimental results. The experiments and computations both show that segmenting the liner treatment is effective to control the scatter of incident mode energy into other modes. CDUCT-LaRC is shown to be a valuable tool to predict trends of liner performance with liner configuration.

  14. Killer clays! Natural antibacterial clay minerals

    USGS Publications Warehouse

    Williams, L.B.; Holland, M.; Eberl, D.D.; Brunet, T.; De Courrsou, L. B.

    2004-01-01

    The clay chemical properties that may be important in medicine were investigated. It was found that natural clay minerals can have striking and very specific effects on microbial populations. The effects can range from potentially enhanced microbial growth to complete sterilization. This paper presents evidence that natural clay minerals can be effective antimicrobial agents.

  15. IRIDIUM LINER FOR NASA 5 LBF CLASS MATERIAL TEST CHAMBER IRIDIUM LINER FOR ATLANTIC RESEARCH CORPORA

    NASA Technical Reports Server (NTRS)

    1995-01-01

    IRIDIUM LINER FOR NASA 5 LBF CLASS MATERIAL TEST CHAMBER IRIDIUM LINER FOR ATLANTIC RESEARCH CORPORATION 5 LBF CLASS ROCKET CHAMBER 25 LBF CLASS 75 HFC 25 TAC CERAMIC COMPOSITE ROCKET CHAMBER FROM REFRACTURY COMPOSITES INC. PURCHASE ORDER C-551941-

  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. Wear materials; 2: Optimizing liner alloy choice

    SciTech Connect

    Stefanovic, T. )

    1993-12-01

    This paper describes a new liner designed for a copper ore crusher in Yugoslavia. The experience gained over the past ten years of operation at the Bor copper mines has shown that correct selection of wear material for crusher liners is critical to successful plant performance. With the new wear resistant liners, the crusher development program has increased the concentrator throughput from 8.0 to 9.6 million tons/year. The ultimate goal of the project is to identify the proper liner material that will extend liner life, reduce cyclic stress on major crusher components, and simplify crusher control and adjustment. This paper describes the various liners materials and the mechanisms of wear.

  18. Cost Estimate for Gun Liner Emplacement

    DTIC Science & Technology

    2011-08-01

    Investigations of Explosively-Bonded Gun Tube Liners; ARDEC Technical Report RDAR-WSB-TR-09016; September 2009. 3. Miller, Mark D.; Campo , Frank. Chromium...Watervliet, NY, July 2010. 4. Miller, Mark D.; Campo , Frank; de Rosset, William S. Explosive Bonding of Refractory Metal Liners. in Proceedings of... Campo , Frank; Todaro, Mark; Hydrew, Josh; de Rosset, William S. Ballistic Tests of Explosively-Bonded Gun Tube Liner; ARDEC/Benét Laboratories

  19. 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.

  20. Duct Liner Optimization for Turbomachinery Noise Sources

    DTIC Science & Technology

    1975-11-01

    AD-A279 441lIIIflhIh* NASA TECHNICAL NASA TMA X-72789 MEMORANDUM oo £ 00 r-:. DUCT LINER OPTIMIZATION FOR TURBOMACHINERY w NOISE SOURCES By Harold C...Recipient’s r.atalog No. NASA TM X-72789! 4 Title diid Subtitle 5. Rewrt Date Duct Liner Optimization for Turbomachinery Noise Sources November 1975...profiles is combined wit., a numerical minimization algorithm to predict optimal liner configurations having one, two, and three sections. Source models

  1. 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.

  2. 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.

  3. Imprinted Clay Coil Vessels

    ERIC Educational Resources Information Center

    Lohr, Tresa Rae

    2006-01-01

    The author teaches clay vessel construction in the fifth grade, and it is amazing what can be accomplished in one forty-five minute period when the expectations are clarified in the initial lesson. The author introduces clay coil vessels with a discussion of the sources of clay and how clay relates to fifth-grade science curriculum concepts such…

  4. Elastomer liners for geothermal tubulars Y267 EPDM Liner Program:

    SciTech Connect

    Hirasuna, A.R.; Davis, D.L.; Flickinger, J.E.; Stephens, C.A.

    1987-12-01

    The elastomer, Y267 EPDM, has been identified as a hydrothermally stable material which can operate at temperatures in excess of 320/sup 0/C. The goal of the Y267 Liner Program was to demonstrate the feasibility of using this material as a liner for mild steel tubulars to prevent or mitigate corrosion. If successful, the usage of EPDM lined pipe by the geothermal community may have a significant impact on operating costs and serve as a viable alternative to the use of alloyed tubulars. Tooling procedures were developed under this program to mold a 0.64 cm (0.25'') thick Y267 EPDM liner into a tubular test section 61 cm (2') in length and 19.1 cm (7.5'') in diameter (ID). A successful effort was made to identify a potential coupling agent to be used to bond the elastomer to the steel tubular wall. This agent was found to withstand the processing conditions associated with curing the elastomer at 288/sup 0/C and to retain a significant level of adhesive strength following hydrothermal testing in a synthetic brine at 260/sup 0/C for a period of 166 hours. Bonding tests were conducted on specimens of mild carbon steel and several alloys including Hastelloy C-276. An objective of the program was to field test the lined section of pipe mentioned above at a geothermal facility in the Imperial Valley. Though a test was conducted, problems encountered during the lining operation precluded an encouraging outcome. The results of the field demonstration were inconclusive. 6 refs., 13 figs., 13 tabs

  5. Refractory Metal Liner Processing for M242 Medium Caliber Barrels

    DTIC Science & Technology

    2013-01-01

    public release; distribution unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT The process for attaching a refractory metal liner to a gun tube...known as Gun Liner Emplacement with an Elastomeric Material (GLEEM) has been developed for the 25 mm Bushmaster medium caliber cannon. Stellite 25 liners...liner stretching. 15. SUBJECT TERMS refractory metal, gun tube liner, M242 barrel, elastomer, liner processing 16. SECURITY CLASSIFICATION OF: 17

  6. Common clay and shale

    USGS Publications Warehouse

    Virta, R.L.

    2011-01-01

    The article discusses the latest developments in the global common clay and shale industry, particularly in the U.S. It claims that common clay and shale is mainly used in the manufacture of heavy clay products like brick, flue tile and sewer pipe. The main producing states in the U.S. include North Carolina, New York and Oklahoma. Among the firms that manufacture clay and shale-based products are Mid America Brick & Structural Clay Products LLC and Boral USA.

  7. 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.

  8. Liquid-cooled liner for helmets

    NASA Technical Reports Server (NTRS)

    Williams, B. A.; Elkins, W.

    1974-01-01

    Liner acts as coolant tubing, manifold, and supporting structures. Fabric of waffle-design is made of several integrated channels (or capillaries) through which coolant liquid can flow. Thin and light-weight liner can be incorporated into any type of helmet or head gear.

  9. 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.

  10. 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

  11. 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.

  12. NGC 5252 - a Liner undercover

    NASA Astrophysics Data System (ADS)

    Goncalves, A. C.; Veron, P.; Veron-Cetty, M.-P.

    1998-05-01

    Ground based long slit spectroscopic observations of the nuclear region of NGC 5252, and Hubble Space Telescope (HST) Faint Object Spectrograph (FOS) spectra of the nucleus and two bright knots located 0.36'' NE and 0.31'' SW from it, show that the nuclear region exhibits the characteristics of a Liner with exceptionally strong [O i] emission, all lines being broad (FWHM ~ 1100kms(-1) ), while the gas outside the nucleus has a typical Seyfert 2 spectrum with relatively narrow lines ( ~ 200-300kms(-1) ). We suggest that all the emitting gas is photoionized by the hidden non-thermal nuclear source detected through near-infrared (Kotilainen & Prieto 1995) and X-ray (Cappi et al. 1996) observations, the ionizing continuum, in the case of the central Liner, being ``filtered'' by a matter-bounded highly ionized cloud, hidden from our view by the same material obscuring the central continuum source. Based on observations collected at the Observatoire de Haute-Provence (CNRS, France) and Hubble Space Telescope data obtained from the Space Telescope European Coordinating Facility (ST-ECF) Archive.

  13. 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.

  14. 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.

  15. How to prevent deep-well liner failure

    SciTech Connect

    Durham, K.S.

    1987-11-01

    This article discusses three liner design rules to prevent deep-well liner failure. They are: 1) Always select heavier weight casing, all other things being equal. 2) Always suspect that liner tops and casing shoes will leak. Design accordingly. 3) Liner tension designs should always include ballooning and temperature effects of stimulation. The article also gives some guidelines that will lead to better deep-well liner designs and reduce mechanical risk, according to the author.

  16. Clays in prebiological chemistry

    NASA Technical Reports Server (NTRS)

    Rao, M.; Oro, J.; Odom, D. G.

    1980-01-01

    The ways in which clays have been utilized in studies of prebiological chemistry are reviewed, and an assessment is given of the possible role of clays in prebiological systems. The adsorption of organic molecules on clays has been demonstrated, as has the synthesis of bioorganic monomers in the presence of clays. For instance, amino acids, purines and pyrimidines have been obtained from carbon monoxide and nitric acid in the presence of clays at relatively high temperatures (250-325 C). The oligomerization of biochemical monomers, mediated by clays, has also been shown to result in the formation of polymer molecules basic to life. Clays have also been found to affect the condensation of mononucleotides to oligonucleotides.

  17. Drapery assembly including insulated drapery liner

    DOEpatents

    Cukierski, Gwendolyn

    1983-01-01

    A drapery assembly is disclosed for covering a framed wall opening, the assembly including drapery panels hung on a horizontal traverse rod, the rod having a pair of master slides and means for displacing the master slides between open and closed positions. A pair of insulating liner panels are positioned behind the drapery, the remote side edges of the liner panels being connected with the side portions of the opening frame, and the adjacent side edges of the liner panels being connected with a pair of vertically arranged center support members adapted for sliding movement longitudinally of a horizontal track member secured to the upper horizontal portion of the opening frame. Pivotally arranged brackets connect the center support members with the master slides of the traverse rod whereby movement of the master slides to effect opening and closing of the drapery panels effects simultaneous opening and closing of the liner panels.

  18. Gun Liner Emplacement With an Elastomeric Material

    DTIC Science & Technology

    2010-04-01

    Include area code) 410 -306-0816 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 iii Contents List of Figures iv  List of Tables v...12  Figure 9. Inner diameter measurements for Stellite liners no. 1 and 2...5  Table 2. Bond strength results for 4-in Stellite 25 liners ................................................................6  Table 3. Bond

  19. Liner target interaction experiments on Pegasus II

    SciTech Connect

    Hockaday, M.P.; Chrien, R.E.; Bartsch, R.

    1995-09-01

    The Los Alamos High Energy Density Physics program uses capacitively driven low voltage, inductive-storage pulse power to implode cylindrical targets for hydrodynamics experiments. Once a precision driver liner was characterized an experimental series characterizing the aluminum target dynamics was performed. The target was developed for shock-induced quasi-particle ejecta experiments including holography. The concept for the Liner shock experiment is that the driver liner is used to impact the target liner which then accelerates toward a collimator with a slit in it. A shock wave is set up in the target liner and as the shock emerges from the back side of the target liner, ejecta are generated. By taking a laser hologram the particle distribution of the ejecta are hoped to be determined. The goal for the second experimental series was to characterize the target dynamics and not to measure and generate the ejecta. Only the results from the third shot, Pegasus II-26 fired April 26th, 1994, from the series is discussed in detail. The second experimental series successfully characterized the target dynamics necessary to move forward towards the planned quasi-ejecta experiments.

  20. 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.

  1. Tests for the evaluation of ammonium attenuation in MSW landfill leachate by adsorption into bentonite in a landfill liner.

    PubMed

    Pivato, A; Raga, R

    2006-01-01

    Uncontrolled leachate emissions are one of the key factors in the environmental impact of municipal solid waste (MSW) landfills. The concentration of ammonium, given the anaerobic conditions in traditional landfills, can remain significantly high for a very long period of time, as degradation does not take place and volatilisation is not significant (the pH is not high enough to considerably shift the equilibrium towards un-ionised ammonia). Recent years have witnessed a continuous enhancement of landfill technology in order to minimize uncontrolled emissions into the environment; bottom lining systems have been improved and more attention has been devoted to the study of the attenuation of the different chemicals in leachate in case of migration through the mineral barrier. Different natural materials have been considered for use as components of landfill liners in the last years and tested in order to evaluate the performance of the different alternatives. Among those materials, bentonite is often used, coupled with other materials in two different ways: in addition to in situ soil or in geocomposite clay liner (GCL). A lab-scale test was carried out in order to further investigate the influence of bentonite on the attenuation of ammonium in leachate passing through a landfill liner. Two different tests were conducted: a standardized batch test with pulverized bentonite and a batch test with compacted bentonite. The latter was proposed in order to better simulate the real conditions in a landfill liner. The two tests produced values for the partition coefficient K(d) higher than the average measured for other natural materials usually utilized as components of landfill liners. Moreover, the two tests showed similar results, thus providing a further validation of the suitability of the standard batch test with pulverized bentonite. A thorough knowledge of attenuation processes of ammonium in landfill liners is the basis for the application of risk analysis models

  2. 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.

  3. Permeability of Clay Concretes

    NASA Astrophysics Data System (ADS)

    Solomon, F.; Ekolu, S. O.

    2015-11-01

    This paper presents an investigation on the effect of clay addition on water permeability and air permeability of concretes. Clay concrete mixes consisted of 0 to 40% clay content incorporated as cement replacement. Flow methods using triaxial cells and air permeameters were used for measuring the injected water and air flows under pressure. It was found that the higher the clay content in the mixture, the greater the permeability. At higher water-cement ratios (w/c), the paste matrix is less dense and easily allows water to ingress into concrete. But at high clay contents of 30 to 40% clay, the variation in permeability was significantly diminished among different concrete mixtures. It was confirmed that air permeability results were higher than the corresponding water permeability values when all permeability coefficients were converted to intrinsic permeability values.

  4. Modified clay sorbents

    DOEpatents

    Fogler, H. Scott; Srinivasan, Keeran R.

    1990-01-01

    A novel modified clay sorbent and method of treating industrial effluents to remove trace pollutants, such as dioxins, biphenyls, and polyaromatics such as benzo(a)pyrene and pentachlorophenol. The novel clay sorbent has a composite structure in which the interlayer space of an expandable clay, such as smectite, is filled with polyvalent or multivalent inorganic cations which forces weaker surfactant cations to locate on the surface of the clay in such an orientation that the resulting composite is hydrophilic in nature. A specific example is cetylpyridinium-hydroxy aluminum-montmorillonite. In certain embodiments, a non-expanding clay, such as kaolinite, is used and surfactant cations are necessarily located on an external surface of the clay. A specific example is cetylpyridinium-kaolinite.

  5. Common clay and shale

    USGS Publications Warehouse

    Virta, R.L.

    2000-01-01

    Part of the 1999 Industrial Minerals Review. The clay and shale market in 1999 is reviewed. In the U.S., sales or use of clay and shale increased from 26.4 million st in 1998 to 27.3 million st in 1999, with an estimated 1999 value of production of $143 million. These materials were used to produce structural clay products, lightweight aggregates, cement, and ceramics and refractories. Production statistics for clays and shales and for their uses in 1999 are presented.

  6. Engineered clay-shredded tyre mixtures as barrier materials

    SciTech Connect

    Al-Tabbaa, A.; Aravinthan, T.

    1997-12-31

    An engineered clay consisting of kaolin and bentonite was mixed with shredded tyre in various weight percentages and examined for use as a constituent in a landfill liner. The clay-tyre mixtures properties in terms of compaction, unconfined compressive strength, permeability to water and paraffin, leachability, stress-strain behaviour, free swell behaviour and swelling pressure were investigated. The results show that the dry density and strength reduced with the addition of tyre and also with increased tyre content but that good interaction was developed between the clay and tyre. The strain at failure increased showing reinforcing effect of the tyre. The permeability to paraffin was considerably reduced compared to that to water due to the presence of the tyre which caused high swelling pressures to develop. The leachability results indicate initial high concentrations leaching out of the soil-tyre mixtures which will be subjected to dilution in the environment. This work adds evidence to the potential advantages of using soil-tyre mixtures as a landfill liner material.

  7. 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.

  8. 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.

  9. Experimental study of Human Adenoviruses interactions with clays

    NASA Astrophysics Data System (ADS)

    Bellou, Maria; Syngouna, Vasiliki; Paparrodopoulos, Spyros; Vantarakis, Apostolos; Chrysikopoulos, Constantinos

    2014-05-01

    Clays are used to establish low permeability liners in landfills, sewage lagoons, water retention ponds, golf course ponds, and hazardous waste sites. Human adenoviruses (HAdVs) are waterborne viruses which have been used as viral indicators of fecal pollution. The objective of this study was to investigate the survival of HAdV in static and dynamic clay systems. The clays used as a model were crystalline aluminosilicates: kaolinite and bentonite. The adsorption and survival of HAdVs onto these clays were characterized at two different controlled temperatures (4 and 25o C) under static and dynamic batch conditions. Control tubes, in the absence of clay, were used to monitor virus inactivation due to factors other than adsorption to clays (e.g. inactivation or sorption onto the tubes walls). For both static and dynamic batch experiments, samples were collected for a maximum period of seven days. This seven day time - period was determined to be sufficient for the virus-clay systems to reach equilibrium. To infer the presence of infectious HAdV particles, all samples were treated with Dnase and the extraction of viral nucleid acid was performed using a commercial viral RNA kit. All samples were analyzed by Real - Time PCR which was used to quantify viral particles in clays. Samples were also tested for virus infectivity by A549 cell cultures. Exposure time intervals in the range of seven days (0.50-144 hours) resulted in a load reduction of 0.74 to 2.96 logs for kaolinite and a reduction of 0.89 to 2.92 for bentonite. Furthermore, virus survival was higher onto bentonite than kaolinite (p

  10. Columns in Clay

    ERIC Educational Resources Information Center

    Leenhouts, Robin

    2010-01-01

    This article describes a clay project for students studying Greece and Rome. It provides a wonderful way to learn slab construction techniques by making small clay column capitols. With this lesson, students learn architectural vocabulary and history, understand the importance of classical architectural forms and their influence on today's…

  11. The Science of Clay

    ERIC Educational Resources Information Center

    Warwick, Sharon

    2005-01-01

    Students' natural curiosity provides a rich opportunity for teachers to make meaningful scientific connections between art and ceramics that will enhance the understanding of both natural forces and scientific aspects at work in the creation of clay artworks. This article discusses the scientific areas of study related to clay, which include…

  12. Clay Portrait Boxes

    ERIC Educational Resources Information Center

    Wilbert, Nancy Corrigan

    2009-01-01

    In an attempt to incorporate sculptural elements into her ceramics program, the author decided to try direct plaster casting of the face to make a plaster mold for clay. In this article, the author shares an innovative ceramics lesson that teaches students in making plaster casts and casting the face in clay. This project gives students the…

  13. Common clay and shale

    USGS Publications Warehouse

    Virta, R.L.

    2003-01-01

    Part of the 2002 industrial minerals review. The production, consumption, and price of shale and common clay in the U.S. during 2002 are discussed. The impact of EPA regulations on brick and structural clay product manufacturers is also outlined.

  14. Finicky clay divers

    NASA Astrophysics Data System (ADS)

    Cordry, Sean M.

    1998-02-01

    Clay spheres dropped into a dilute vinegar/baking-soda solution accumulate CO2 bubbles on their surfaces. Spheres below a certain size will then float, otherwise they remain sunken. Students must determine the maximum size that will float by considering the net density of the clay/bubble system.

  15. 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.

  16. SDU6 Interior Liner Testing & Evaluation

    SciTech Connect

    Skidmore, T. E.

    2016-10-14

    Two liner materials (Marseal® M-3500 and REMA Chemoline® 4CN) proposed for use as a liner inside the Saltstone Disposal Unit 6 (SDU6) were subjected to specific ASTM tests (tensile and lap-shear) after immersion in 50% and 100% simulant solutions for 1000 hours at the Savannah River Ecology Laboratory. Both liner materials exhibited good resistance to the simulant chemistry, at least based on the tests performed and the test duration/conditions imposed. In lap-shear tests, both materials failed in the base material rather than peeling apart, confirming good adhesion. The REMA 4CN bromobutyl elastomer showed superior bonding characteristics and absence of warping or delamination at the conditions tested. The Marseal M-3500 material (PVC/EVA blend with polyester reinforcement) exhibited deformation and debonding in some locations. The cause of the deformation and delamination observed in the Marseal M-3500 material is not fully known, but possibly attributed to thermomechanical stress at immersion temperatures, and the thermoplastic nature of the material. The immersion temperature (68 °C) is slightly greater than the maximum use temperature limit quoted for the Marseal M- 3500 liner (65 °C), though the basis for the service limit is unknown. The testing performed was limited in scope and only for these two liner materials. These tests were primarily performed to screen for severe incompatibility or short-term degradation in Saltstone bleedwater simulants at bounding solution temperatures. Additional testing is recommended to assess long-term performance and the overall service life of the liner.

  17. 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

  18. 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

  19. FOAM-IN-PLACE FORM FITTING HELMET LINERS

    DTIC Science & Technology

    A urethane foam formulation has been developed to produce foamed-in-place helmet liners for Air Force crash or flying helmets. High density urethane...foam helmet liners has been foamed-in-place directly on the flying crew member’s head, producing a perfectly fitting helmet liner with a minimum of...time, labor and inconvenience. These liners were produced at an extremely modest cost. Design and fabrication of a suitable mold in which the helmet

  20. 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).

  1. 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.

  2. Comparative evaluation of liner materials for inactive uranium-mill-tailings piles

    SciTech Connect

    Buelt, J.L.; Barnes, S.M.

    1981-01-01

    Under the funding of the Department of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Program, Pacific Northwest Laboratory (PNL) has completed the initial accelerated testing phase of eight candidate liner materials. The tests were designed to comparatively evaluate the long term effectiveness of liner materials as a radionuclide and hazardous chemical leachate barrier. The eight materials tested were selected from a technical review of published literature and industrial specialists. Conditions were then identified that would accelerate the aging processes expected in a uranium tailings environment for 1000 years. High calcium leachates were forced through thin layers of clay liners to accelerate the ion exchange rate of sodium and calcium. Asphalt and synthetic materials were accelerated by exposure to elevate temperatures, high concentrations of oxygen, and increased strengths of aqueous oxidizing agents. By comparing the changes of permeability with time of exposure, the most acceptable materials were then identified. These materials are a catalytically airblown asphalt membrane and natural soil amended with sodium bentonite. Both materials showed an increased resistance to leachate penetration throughout the exposure period with final permeabilities less than 10/sup -7/ cm/s. In addition, the asphalt membrane and sodium bentonite are among the least expensive materials to install at a disposal site. Therefore based on their economic and technical merits, these two materials are being evaluated further in field tests at Grand Junction, Colorado.

  3. Clays as prebiotic photocatalysts

    NASA Technical Reports Server (NTRS)

    Coyne, L. M.; Lawless, J.; Lahav, N.; Sutton, S.; Sweeney, M.

    1981-01-01

    Clay minerals catalyze peptide bond formation in fluctuating environments. A number of plausible mechanisms have been proposed and tested. The possibility that clays may actually be energizing the reaction by means of electronic excitation, creating mobile or trapped holes and electrons in the lattice, is explored. It has been discovered that clays emit light upon dehydration. The correlation between dehydration-induced, or thermoluminescent, processes and the yield of glycine oligomers after treatments known to affect the luminescent yields is being tested, in an effort to understand the catalytic mechanism

  4. Precision solid liner experiments on Pegasus II

    SciTech Connect

    Bowers, R.L.; Brownell, J.H.; Lee, H.

    1995-09-01

    Pulsed power systems have been used in the past to drive solid liner implosions for a variety of applications. In combination with a variety of target configurations, solid liner drivers can be used to compress working fluids, produce shock waves, and study material properties in convergent geometry. The utility of such a driver depends in part on how well-characterized the drive conditions are. This, in part, requires a pulsed power system with a well-characterized current wave form and well understood electrical parameters. At Los Alamos, the authors have developed a capacitively driven, inductive store pulsed power machine, Pegasus, which meets these needs. They have also developed an extensive suite of diagnostics which are capable of characterizing the performance of the system and of the imploding liners. Pegasus consists of a 4.3 MJ capacitor bank, with a capacitance of 850 {micro}f fired with a typical initial bank voltage of 90 kV or less. The bank resistance is about 0.5 m{Omega}, and bank plus power flow channel has a total inductance of about 24 nH. In this paper the authors consider the theory and modeling of the first precision solid liner driver fielded on the LANL Pegasus pulsed power facility.

  5. 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.

  6. 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.

  7. A liner timeline at Grand Central Sanitation

    SciTech Connect

    Woods, R.

    1994-08-01

    Since the promulgation of the minimum landfill liner requirements under RCRA's Subtitle D in September 1991, nearly every operating landfill in the US that has expanded horizontally has been brought up to speed with basic environmental protection measures, i.e., liners, leachate collection groundwater monitoring, etc. For most landfills, however, these changes did not happen overnight. For more than a decade, most of the states and countless private landfills have been anticipating the advent of Subtitle D and have been upgrading outdated landfills long before the federal regulations were enforced. Grand Central Sanitation, Inc. (GCS, Pen Argyl, Pa.), for example, is a case in point. The family-run company's sanitary landfill began operation as a 52-acre, natural renovation, or earthen barrier, fill in the early 1950s and its first two fill areas, now closed, had only natural soils as a liner. Today, GCS's facility has more than doubled its permitted capacity. Its 10th disposal cell, now under construction, is triple-lined with the latest synthetic geomembranes, including high-density polyethylene (HDPE) liners, geotextiles, geonets, and leachate collection systems.

  8. 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.

  9. Evaluation of multidimensional transport through a field-scale compacted soil liner

    USGS Publications Warehouse

    Willingham, T.W.; Werth, C.J.; Valocchi, A.J.; Krapac, I.G.; Toupiol, C.; Stark, T.D.; Daniel, D.E.

    2004-01-01

    A field-scale compacted soil liner was constructed at the University of Illinois at Urbana-Champaign by the U.S. Environmental Protection Agency (USEPA) and Illinois State Geological Survey in 1988 to investigate chemical transport rates through low permeability compacted clay liners (CCLs). Four tracers (bromide and three benzoic acid tracers) were each added to one of four large ring infiltrometers (LRIs) while tritium was added to the pond water (excluding the infiltrometers). Results from the long-term transport of Br- from the localized source zone of LRI are presented in this paper. Core samples were taken radially outward from the center of the Br- LRI and concentration depth profiles were obtained. Transport properties were evaluated using an axially symmetric transport model. Results indicate that (1) transport was diffusion controlled; (2) transport due to advection was negligible and well within the regulatory limits of ksat???1 ?? 10-7 cm/s; (3) diffusion rates in the horizontal and vertical directions were the same; and (4) small positioning errors due to compression during soil sampling did not affect the best fit advection and diffusion values. The best-fit diffusion coefficient for bromide was equal to the molecular diffusion coefficient multiplied by a tortuosity factor of 0.27, which is within 8% of the tortuosity factor (0.25) found in a related study where tritium transport through the same liner was evaluated. This suggests that the governing mechanisms for the transport of tritium and bromide through the CCL were similar. These results are significant because they address transport through a composite liner from a localized source zone which occurs when defects or punctures in the geomembrane of a composite system are present. ?? ASCE.

  10. Common clay and shale

    USGS Publications Warehouse

    Virta, R.L.

    2004-01-01

    Part of the 2003 industrial minerals review. The legislation, production, and consumption of common clay and shale are discussed. The average prices of the material and outlook for the market are provided.

  11. The Performance of Four Different Mineral Liners on the Transportation of Chlorinated Phenolic Compounds to Groundwater in Landfills.

    PubMed

    Adar, Elanur; Bilgili, Mehmet Sinan

    2015-01-01

    The aim of this study was to investigate the efficiency of four different mineral liners (clay, bentonite, kaoline, and zeolite) which could be utilized to prevent the transport of phenolic compounds to groundwater through alternative liner systems. Four laboratory-scale HDPE reactors with 80 cm height and 40 cm inner diameter were operated for a period of 180 days. Results indicated that the transport of mono- or dichlorophenols is significantly prevented by the liner systems used, while the transport of highly chlorinated phenolic compounds cannot be prevented by the landfill liner system effectively. Highly chlorinated phenolic compounds in groundwater can be found in higher concentrations than the leachate, as a result of the degradation and transformation of these compounds. Thus, the analysis of highly chlorinated phenolic compounds such as 2,4,6-TCP, 2,3,6-TCP, 3,4,5-TCP, and PCP is of great significance for the studies to be conducted on the contamination of groundwater around landfills.

  12. The Performance of Four Different Mineral Liners on the Transportation of Chlorinated Phenolic Compounds to Groundwater in Landfills

    PubMed Central

    Adar, Elanur; Bilgili, Mehmet Sinan

    2015-01-01

    The aim of this study was to investigate the efficiency of four different mineral liners (clay, bentonite, kaoline, and zeolite) which could be utilized to prevent the transport of phenolic compounds to groundwater through alternative liner systems. Four laboratory-scale HDPE reactors with 80 cm height and 40 cm inner diameter were operated for a period of 180 days. Results indicated that the transport of mono- or dichlorophenols is significantly prevented by the liner systems used, while the transport of highly chlorinated phenolic compounds cannot be prevented by the landfill liner system effectively. Highly chlorinated phenolic compounds in groundwater can be found in higher concentrations than the leachate, as a result of the degradation and transformation of these compounds. Thus, the analysis of highly chlorinated phenolic compounds such as 2,4,6-TCP, 2,3,6-TCP, 3,4,5-TCP, and PCP is of great significance for the studies to be conducted on the contamination of groundwater around landfills. PMID:26759828

  13. Influence of atomic processes on the implosion of plasma liners

    SciTech Connect

    Kim, Hyoungkeun; Zhang Lina; Samulyak, Roman; Parks, Paul

    2012-08-15

    The influence of atomic physics processes on the implosion of plasma liners for magneto-inertial nuclear fusion has been investigated numerically by using the method of front tracking in spherically symmetric geometry and equation of state models accounting for dissociation and ionization. Simulation studies of the self-collapse of argon liners to be used in the Los Alamos Plasma Liner Experiment (PLX) program have been performed as well as studies of implosion of deuterium and argon liners on plasma targets. Results show that atomic processes in converging liners reduce the temperature of liners and increase the Mach number that results in the increase of the stagnation pressure and the fusion energy gain. For deuterium and argon liners imploding on plasma targets, dissociation and ionization increased the stagnation pressure and the fusion energy gain by the factor of 1.5 (deuterium) and 2 (argon) correspondingly. Similarly, ionization during the self-collapse of argon liners leads to approximately doubling of the Mach number and the stagnation pressure. The influence of the longitudinal density spread of the liner has also been investigated. The self-collapse stagnation pressure decreased by the factor of 8.7 when the initial position of the liner was shifted from the merging radius (33 cm) to the PLX chamber edge (137.2 cm). Simulations with and without the heat conduction demonstrated that the heat conduction has negligible effect on the self-collapse pressure of argon liners.

  14. 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.

  15. Clay Mineral: Radiological Characterization

    SciTech Connect

    Cotomacio, J. G.; Silva, P. S. C.; Mazzilli, B. P

    2008-08-07

    Since the early days, clays have been used for therapeutic purposes. Nowadays, most minerals applied as anti-inflammatory, pharmaceutics and cosmetic are the clay minerals that are used as the active ingredient or, as the excipient, in formulations. Although their large use, few information is available in literature on the content of the radionuclide concentrations of uranium and thorium natural series and {sup 40}K in these clay minerals.The objective of this work is to determine the concentrations of {sup 238}U, {sup 232}Th, {sup 226}Ra, {sup 228}Ra, {sup 210}Pb and {sup 40}K in commercial samples of clay minerals used for pharmaceutical or cosmetic purposes. Two kinds of clays samples were obtained in pharmacies, named green clay and white clay.Measurement for the determination of {sup 238}U and {sup 232}Th activity concentration was made by alpha spectrometry and gamma spectrometry was used for {sup 226}Ra, {sup 228}Ra, {sup 210}Pb and {sup 40}K determination. Some physical-chemical parameters were also determined as organic carbon and pH. The average activity concentration obtained was 906{+-}340 Bq kg{sup -1} for {sup 40}K, 40{+-}9 Bq kg{sup -1} for {sup 226}Ra, 75{+-}9 Bq kg{sup -1} for {sup 228}Ra, 197{+-}38 Bq kg{sup -1} for {sup 210}Pb, 51{+-}26 Bq kg{sup -1} for {sup 238}U and 55{+-}24 Bq kg{sup -1} for {sup 232}Th, considering both kinds of clay.

  16. Common clay and shale

    USGS Publications Warehouse

    Virta, R.L.

    2006-01-01

    At present, 150 companies produce common clay and shale in 41 US states. According to the United States Geological Survey (USGS), domestic production in 2005 reached 24.8 Mt valued at $176 million. In decreasing order by tonnage, the leading producer states include North Carolina, Texas, Alabama, Georgia and Ohio. For the whole year, residential and commercial building construction remained the major market for common clay and shale products such as brick, drain tile, lightweight aggregate, quarry tile and structural tile.

  17. Clay slurry and engineered soils as containment technologies for remediation of contaminated sites

    SciTech Connect

    Williams, J.R.; Dudka, S.; Miller, W.P.; Johnson, D.O.

    1997-12-31

    Clay Slurry and Engineered Soils are containment technologies for remediation of waste disposal sites where leaching, groundwater plumes and surface runoff of contaminants are serious ecological hazards to adjacent environments. This technology is a patent-pending process which involves the use of conditioned clay materials mixed with sand and water to form a readily pourable suspension, a clay slurry, which is either placed into a trench barrier system or allowed to de-water to create Engineered Soils. The Engineered Soil forms a layer impervious to water and air, therefore by inhibiting both water and oxygen from penetrating through the soil the material. This material can be installed in layers and as a vertical barrier to create a surface barrier containment system. The clay percentage in the clay slurry and Engineered Soils varies depending on site characteristics and desired performance standards. For example Engineered Soils with 1-2% of clay (dry wt.) had a hydraulic conductivity (K) of 10{sup -8} to 10{sup -1} cm/sec. Tests of tailing materials from a kyanite and pyrite mine showed that the clay slurry was effective not only in reducing the permeability of the treated tailings, but also in decreasing their acidity due to the inherent alkalinity of the clay. The untreated tailings had pH values in the range of 2.4 - 3.1; whereas, the effluent from clay and tailings mixtures had pH values in a slightly alkaline range (7.7-7.9). Pug-mills and high volume slurry pumps can be readily adapted for use in constructing and placing caps and creating Engineered Soils. Moreover, material on site or from a local sand supply can be used to create clay slurries and engineered soils. Clay materials used in cap construction are likewise readily available commercially. As a result, the clay slurry system is very cost effective compared to other capping systems, including the commonly used High Density Polyethylene (HDPE) liner systems.

  18. 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.

  19. 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.

  20. The utilization of sepiolite in landfill liners.

    PubMed

    Güney, Y; Ozdemir, H V

    2005-05-01

    In this study, sepiolite and natural soil-added sepiolite mixtures were studied to find out whether they can be used as compacted landfill liner, as they are an economic alternative to the other compacted day liners or not. Geotechnical and physico-chemical properties of sepiolite and sepiolite mixtures, containing 25% and 50% natural soil by weight, and compacted at water contents ranging from 35% to 60%, were determined by hydraulic conductivity, leachate analysis, unconfined compression strength, consolidation, volumetric shrinkage and swelling tests. The test results showed that the compacted natural soil-added sepiolite mixtures exhibit lower permeability and swelling properties, and higher compressive strength than pure sepiolite. The overall evaluation of the results has revealed that the natural soil-added sepiolite showed good promise and it can be used as a landfill barrier due to its high capacity of contaminant adsorption.

  1. Dewatering of industrial clay wastes

    SciTech Connect

    Smelley, A.G.; Scheiner, B.J.; Zatko, J.R.

    1980-01-01

    As a part of research conducted to effect pollution a dewatering technique that allows for disposal of clay wastes, for reuse of water now lost with clays, and for reclamation of mined land was developed. The technique utilizes a high-molecular-weight nonionic polyethylene oxide polymer (PEO) that has the ability to flocculate and dewater materials containing clay wastes. In laboratory experiments, coal-clay waste, potash-clay brine slurry, phosphatic clay waste, uranium tailings, and talc tailings were successfully consolidated. Coal-clay waste was consolidated from 3.6 to 57%; potash-clay brine slurry was consolidated from 3.8 to 35%; phosphatic clay waste from 15.6 to 49%; uranium tailings from 15.4 to 67%; tailings from talc production from 9.7 to 53%; and an acidic TiO/sub 2/ slurr slurry from 1.68 to 30%.

  2. Explosively Bonded Gun Tube Liner Development

    DTIC Science & Technology

    2015-04-01

    William S de Rosset prepared by Oak Ridge Institute for Science and Education Oak Ridge, TN 37830-0177 under contract ORISE 1120-1120-99...William S de Rosset Weapons and Materials Research Directorate, ARL prepared by Oak Ridge Institute for Science and Education Oak Ridge, TN...COVERED (From - To) 12 January 2014–1 January 2015 4. TITLE AND SUBTITLE Explosively Bonded Gun Tube Liner Development 5a. CONTRACT NUMBER ORISE 1120

  3. 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.

  4. Cavitation modeling and diesel engine cylinder liners

    NASA Astrophysics Data System (ADS)

    Chandekar, Gautam; Pardue, Sally

    2003-10-01

    A common occurrence of cavitation damage is the waterside pitting of a wet sleeve liner in a diesel engine. The automotive industry utilizes an ultrasonic test of 20 kHz according to ASTM standards to quantify the effectiveness of engine coolant additives to prevent damage. However, recent tests indicate a mismatch between the ultrasonic test results and actual engine test runs. The focus of this study is to generate numerical models of bubble dynamics using already published literature. In most of the published papers higher-range frequencies (ultrasonic >15 kHz) are used. It is useful to explore the results of lower excitation frequencies as the vibrating frequencies of a diesel engine liner are between 500-9000 Hz. A Rayleigh-Plesset equation, nonlinear in nature, is used to plot the relation between bubble radius and time. Plots of the numerical solution from MATLAB are compared with plots published in the literature. Results from when the frequency of excitation is changed to the liner wall frequency and the fluid properties are changed to approximate engine conditions will be presented. Future work will examine the energy released by the bubble collapse and its correlation with erosion measured as mass change in a standard test button.

  5. An analytical model for contaminant transport in landfill composite liners considering coupled effect of consolidation, diffusion, and degradation.

    PubMed

    Xie, Haijian; Yan, Huaxiang; Feng, Shijin; Wang, Qiao; Chen, Peixiong

    2016-10-01

    One-dimensional mathematical model is developed to investigate the behavior of contaminant transport in landfill composite liner system considering coupled effect of consolidation, diffusion, and degradation. The first- and second-type bottom boundary conditions are used to derive the steady-state and quasi-steady-state analytical solutions. The concentration profiles obtained by the proposed analytical solution are in good agreement with those obtained by the laboratory tests. The bottom concentration and flux of the soil liners can be greatly reduced when the degradation effect and porosity changing are considered. For the case under steady-state, the bottom flux and concentration for the case with t 1/2 =10 years can be 2.8 and 5.5 times lower than those of the case with t 1/2 =100 years, respectively. The bottom concentration and flux of the soil liners can be greatly reduced when the coefficient of volume compressibility decreases. For quasi-steady-state and with t 1/2 = 10 years, the bottom flux and concentration for the case with m v  = 0.02/MPa can be 17.4 and 21 times lower than the case with m v  = 0.5/MPa. This may be due to the fact that the true fluid velocity induced by consolidation is greater for the case with high coefficient of volume compressibility. The bottom flux for the case with single compacted clay liner (CCL) can be 1.5 times larger than that for the case with GMB/CCL considering diffusion and consolidation for DCM. The proposed analytical model can be used for verification of more complicated numerical models and assessment of the coupled effect of diffusion, consolidation, and degradation on contaminant transport in landfill liner systems.

  6. 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.

  7. Shaped Charge Liner Materials: Resources, Processes, Properties, Costs, and Applications

    DTIC Science & Technology

    1991-02-01

    SUBTITLE 5. FUNDING NUMBERS Shaped Charge Liner Materials: Resources, Processes, Properties, Costs, and Applications 2 6. AUTHOC Steven M. Buc 7...summaries of the mineral availability, Cq prmarymetal refinement processeb, material costs in raw form and as finished shaped charge liners , relevant... liner materials. 94-11479 gI 14, SUBJECT TERMS iSt NUMBER OF PAGIS 13chrg wrhad :xplosively formed penetrators material R. PRCE COEV" processing

  8. Composite liner, multi-megabar shock driver development

    SciTech Connect

    Bartsch, R.R.; Clark, D.A.; Morgan, D.V.

    1998-12-31

    A magnetically imploded, cylindrical, multi-layer liner is under development for use as an equation of state shock driver using energetic, pulsed-power sources. The stability and uniformity of the imploding liner has been investigated on the Pegasus pulsed-power facility at liner velocities of >7 mm/usec. Using a thick aluminum driver layer to carry the current and a platinum impactor layer to generate the shock on impact with a target, the expected platinum-on-platinum shock level is 6 to 8 Mbar for operation of the Pegasus capacitor bank at the maximum charge voltage of 90 kV. The initial liner design utilized 8 grams of aluminum with a 1 gram (12-micron thick) layer of platinum on the inside. The inner surface was observed with flash radiography oriented transversely to the axis of the collapsing liner, and with fiber-optic time-of-arrival detectors on the target. Short wavelength perturbations of the inner surface along the axial direction were observed with amplitudes between 200 to 400 microns. A second liner was evaluated with increased aluminum mass and thickness to avoid drive current penetration and the resulting melting and susceptibility to Rayleigh Taylor instabilities. With 10 grams of aluminum at an initial radius of 2.5 cm, the initial liner thickness was almost 50% greater than for the first liner. This liner was observed to be more uniform at impact than the initial design, with perturbed amplitudes less than 100 to 200 microns at wavelengths of a few millimeters. Based on these results a third experiment is being prepared with the 10 gram aluminum liner of the second design and with a 1 gram, 15 micron platinum impactor layer. Liner stability measurements will be presented, application of this liner system to EOS measurement will be discussed, and the evolution to higher energy experiments on ATLAS will be presented.

  9. LIQUID BUTANE FILLED LOAD FOR A LINER DRIVEN PEGASUS EXPERIMENT

    SciTech Connect

    M.A. SALAZAR; W. ANDERSON; ET AL

    2001-06-01

    A hydrogen rich, low density liquid, contained within the internal volume of a cylindrical liner, was requested of the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division for one of the last liner driven experiments conducted on the Los Alamos Pegasus facility. The experiment was a continuation of the Raleigh-Taylor hydrodynamics series of experiments and associated liners that have been described previously [1,2].

  10. Liquid butane filled load for a liner driven Pegasus experiment.

    SciTech Connect

    Salazar, M. A.; Armijo, E. V.; Anderson, W. E.; Atchison, W. L.; Bartos, J. J.; Garcia, F.; Randolph, B.; Sheppard, M. G.; Stokes, J. L.

    2001-01-01

    A hydrogen rich, low density liquid, contained within the internal volume of a cylindrical liner, was requested of the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division for one of the last liner driven experiments conducted on the Los Alamos Pegasus facility. The experiment (Fig.1) was a continuation of the Raleigh-Taylor hydrodynamics series of experiments and associated liners that have been described previously.

  11. Long-term non-isothermal reactive transport model of compacted bentonite, concrete and corrosion products in a HLW repository in clay

    NASA Astrophysics Data System (ADS)

    Mon, Alba; Samper, Javier; Montenegro, Luis; Naves, Acacia; Fernández, Jesús

    2017-02-01

    Radioactive waste disposal in deep geological repositories envisages engineered barriers such as carbon-steel canisters, compacted bentonite and concrete liners. The stability and performance of the bentonite barrier could be affected by the corrosion products at the canister-bentonite interface and the hyper-alkaline conditions caused by the degradation of concrete at the bentonite-concrete interface. Additionally, the host clay formation could also be affected by the hyper-alkaline plume at the concrete-clay interface. Here we present a non-isothermal multicomponent reactive transport model of the long-term (1 Ma) interactions of the compacted bentonite with the corrosion products of a carbon-steel canister and the concrete liner of the engineered barrier of a high-level radioactive waste repository in clay. Model results show that magnetite is the main corrosion product. Its precipitation reduces significantly the porosity of the bentonite near the canister. The degradation of the concrete liner leads to the precipitation of secondary minerals and the reduction of the porosity of the bentonite and the clay formation at their interfaces with the concrete liner. The reduction of the porosity becomes especially relevant at t = 104 years. The zones affected by pore clogging at the canister-bentonite and concrete-clay interfaces at 1 Ma are approximately equal to 1 and 3.3 cm thick, respectively. The hyper-alkaline front (pH > 8.5) spreads 2.5 cm into the clay formation after 1 Ma. Our simulation results share the key features of the models reported by others for engineered barrier systems at similar chemical conditions, including: 1) Pore clogging at the canister-bentonite and concrete-clay interfaces; 2) Narrow alteration zones; and 3) Limited smectite dissolution after 1 Ma.

  12. Long-term non-isothermal reactive transport model of compacted bentonite, concrete and corrosion products in a HLW repository in clay.

    PubMed

    Mon, Alba; Samper, Javier; Montenegro, Luis; Naves, Acacia; Fernández, Jesús

    2017-02-01

    Radioactive waste disposal in deep geological repositories envisages engineered barriers such as carbon-steel canisters, compacted bentonite and concrete liners. The stability and performance of the bentonite barrier could be affected by the corrosion products at the canister-bentonite interface and the hyper-alkaline conditions caused by the degradation of concrete at the bentonite-concrete interface. Additionally, the host clay formation could also be affected by the hyper-alkaline plume at the concrete-clay interface. Here we present a non-isothermal multicomponent reactive transport model of the long-term (1Ma) interactions of the compacted bentonite with the corrosion products of a carbon-steel canister and the concrete liner of the engineered barrier of a high-level radioactive waste repository in clay. Model results show that magnetite is the main corrosion product. Its precipitation reduces significantly the porosity of the bentonite near the canister. The degradation of the concrete liner leads to the precipitation of secondary minerals and the reduction of the porosity of the bentonite and the clay formation at their interfaces with the concrete liner. The reduction of the porosity becomes especially relevant at t=10(4)years. The zones affected by pore clogging at the canister-bentonite and concrete-clay interfaces at 1Ma are approximately equal to 1 and 3.3cm thick, respectively. The hyper-alkaline front (pH>8.5) spreads 2.5cm into the clay formation after 1Ma. Our simulation results share the key features of the models reported by others for engineered barrier systems at similar chemical conditions, including: 1) Pore clogging at the canister-bentonite and concrete-clay interfaces; 2) Narrow alteration zones; and 3) Limited smectite dissolution after 1Ma.

  13. 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.

  14. Moving Along: Sporting Clay.

    ERIC Educational Resources Information Center

    Hiller, Peter

    2002-01-01

    Presents a junior high school student art project where three-dimensional art sculptures of surfing, snow boarding, or dirt biking were created. Discusses how the students created their three-dimensional works of art using a clay-slab technique. (CMK)

  15. Rattles of Clay.

    ERIC Educational Resources Information Center

    Banning, Donna

    1983-01-01

    Using the rattles of Native American cultures as inspiration, students used pinching, coiling, and slab and molding techniques to form the bodies of rattles and clay pellets for sound. Surface decoration included glazed and unglazed areas as well as added handles, feathers, and leather. (IS)

  16. Common clay and shale

    USGS Publications Warehouse

    Virta, R.L.

    2001-01-01

    Part of the 2000 annual review of the industrial minerals sector. A general overview of the common clay and shale industry is provided. In 2000, U.S. production increased by 5 percent, while sales or use declined to 23.6 Mt. Despite the slowdown in the economy, no major changes are expected for the market.

  17. Modeling in Ceramic Clay

    ERIC Educational Resources Information Center

    Miller, Louis J.

    1976-01-01

    Modeling is an additive process of building up a sculpture with some plastic material like clay. It affords the student an opportunity to work in three dimensions, a creative relief from the general two-dimensional drawing and design activities that occupy a large segment of time in the art curriculum. (Author/RK)

  18. Bentonite mat demonstration. Final report

    SciTech Connect

    Serrato, M.G.

    1994-12-30

    The Bentonite Mat Demonstration was developed to provide the Environmental Restoration Department with field performance characteristics and engineering data for an alternative closure cover system configuration. The demonstration was initiated in response to regulatory concerns regarding the use of an alternative cover system for future design configurations. These design considerations are in lieu of the US Environmental Protection Agency (EPA) Recommended Design for Closure Cover Systems and specifically a single compacted kaolin clay layer with a hydraulic conductivity of 1 {times} 10{sup {minus}7} cm/sec. This alternative configuration is a composite geosynthetic material hydraulic barrier consisting from bottom to top: 2 ft compacted sandy clay layer (typical local Savannah River Site soil type) that is covered by a bentonite mat--geosynthetic clay liner (GCL) and is overlaid by a 40 mil High Density Polyethylene (HDPE) geomembrane--flexible membrane liner. This effort was undertaken to obtain and document the necessary field performance/engineering data for future designs and meet regulatory technical requirements for an alternative cover system configuration. The composite geosynthetic materials hydraulic barrier is the recommended alternative cover system configuration for containment of hazardous and low level radiological waste layers that have a high potential of subsidence to be used at the Savannah River Site (SRS). This alternative configuration mitigates subsidence effects in providing a flexible, lightweight cover system to maintain the integrity of the closure. The composite geosynthetic materials hydraulic barrier is recommended for the Sanitary Landfill and Low Level Radiological Waste Disposal Facility (LLRWDF) Closures.

  19. Clay Animals and Their Habitats

    ERIC Educational Resources Information Center

    Adamson, Kay

    2010-01-01

    Creating clay animals and their habitats with second-grade students has long been one of the author's favorite classroom activities. Students love working with clay and they also enjoy drawing animal homes. In this article, the author describes how the students created a diorama instead of drawing their clay animal's habitat. This gave students…

  20. 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.

  1. 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.

  2. Conceptual design for high mass imploding liner experiments

    SciTech Connect

    Reinovsky, R.E.; Clark, D.A.; Ekdahl, C.A.

    1996-12-31

    We have summarized some of the motivation behind high energy liner experiments. We have identified the 100-cm-diameter Disk Explosive-Magnetic Gene promising candidate for powering such experiments and described a phenomenological modeling approach used to understand the limits of DEMG operation. We have explored the liner implosion parameter space that can be addressed by such systems and have selected a design point from which to develop a conceptual experiment. We have applied the phenomenological model to the point design parameters and used 1 D MHD tools to assess the behavior of the liner for parameters at the design point. We have not to optimized the choice of pulse power or liner parameters. We conclude that operating in the velocity range of 10-20 km/s, kinetic energies around 100 MJ are practical with currents approaching 200 MA in the liner. Higher velocities (up to almost 40 km/s) are achieved on the inner surface of a thick liner when the liner collapses to I -cm radius. At 6-cm radius the non- optimized liners explored here are attractive drivers for experiments exploring the compression of magnetized plasmas and at 1 cm they are equally attractive drivers for shock wave experiments in the pressure range of 30-100 Mbar. An experiment based on this design concept is scheduled to be conducted in VNIIEF in August 1996.

  3. Cotton liners to mediate glove comfort for greenhouse applicators.

    PubMed

    Stone, J; Coffman, C; Imerman, P M; Song, K; Shelley, M

    2005-10-01

    Greenhouse applicators' acceptance of cotton knit gloves worn as liners under nitrile chemical-resistant gloves (CRG) for pesticide application was investigated through a wear study in Iowa and New York. Comfort was assessed by questionnaires and interviews with 10 applicators. Contamination levels of four pesticides on CRG and liners at thumb, forefinger, palm, and cuff locations were determined by chemical analysis using high-performance liquid chromatography or gas chromatography. Applicators reported feeling more comfortable with cotton liners under their CRG than without and that cotton liners were easy to manage. Contamination was significantly greater on nitrile CRG than on cotton liners underneath, but a few liner specimens had measurable contamination. No significant contamination differences were found between right- and left-hand gloves. Contamination varied significantly by hand location, with cuffs least, and by pesticide, with chlorpyrifos most. These results support the Environmental Protection Agency's recommendation that liners should be disposable, but further work on liners and their laundering feasibility seems indicated.

  4. 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...

  5. Development of Standardized Material Testing Protocols for Prosthetic Liners.

    PubMed

    Cagle, John C; Reinhall, Per G; Hafner, Brian J; Sanders, Joan E

    2017-04-01

    A set of protocols was created to characterize prosthetic liners across six clinically relevant material properties. Properties included compressive elasticity, shear elasticity, tensile elasticity, volumetric elasticity, coefficient of friction (CoF), and thermal conductivity. Eighteen prosthetic liners representing the diverse range of commercial products were evaluated to create test procedures that maximized repeatability, minimized error, and provided clinically meaningful results. Shear and tensile elasticity test designs were augmented with finite element analysis (FEA) to optimize specimen geometries. Results showed that because of the wide range of available liner products, the compressive elasticity and tensile elasticity tests required two test maxima; samples were tested until they met either a strain-based or a stress-based maximum, whichever was reached first. The shear and tensile elasticity tests required that no cyclic conditioning be conducted because of limited endurance of the mounting adhesive with some liner materials. The coefficient of friction test was based on dynamic coefficient of friction, as it proved to be a more reliable measurement than static coefficient of friction. The volumetric elasticity test required that air be released beneath samples in the test chamber before testing. The thermal conductivity test best reflected the clinical environment when thermal grease was omitted and when liner samples were placed under pressure consistent with load bearing conditions. The developed procedures provide a standardized approach for evaluating liner products in the prosthetics industry. Test results can be used to improve clinical selection of liners for individual patients and guide development of new liner products.

  6. 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...

  7. 21 CFR 872.3250 - Calcium hydroxide cavity liner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (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 a prepared cavity before insertion of restorative material, such as amalgam, to protect the pulp of a...

  8. 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, ...

  9. 49 CFR 193.2187 - Nonmetallic membrane liner.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Design Lng Storage Tanks § 193.2187 Nonmetallic membrane liner. A flammable nonmetallic membrane liner may not be used as an inner container in a storage tank....

  10. 49 CFR 193.2187 - Nonmetallic membrane liner.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Design Lng Storage Tanks § 193.2187 Nonmetallic membrane liner. A flammable nonmetallic membrane liner may not be used as an inner container in a storage...

  11. 49 CFR 193.2187 - Nonmetallic membrane liner.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Design Lng Storage Tanks § 193.2187 Nonmetallic membrane liner. A flammable nonmetallic membrane liner may not be used as an inner container in a storage tank....

  12. 49 CFR 193.2187 - Nonmetallic membrane liner.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Design Lng Storage Tanks § 193.2187 Nonmetallic membrane liner. A flammable nonmetallic membrane liner may not be used as an inner container in a storage tank....

  13. 49 CFR 193.2187 - Nonmetallic membrane liner.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Design Lng Storage Tanks § 193.2187 Nonmetallic membrane liner. A flammable nonmetallic membrane liner may not be used as an inner container in a storage tank....

  14. Clay Nanocomposite/Aerogel Sandwich Structures for Cryotanks

    NASA Technical Reports Server (NTRS)

    Miller, Sandi; Leventis, Nicholas; Johnston, J. Chris; Meador, Michael

    2006-01-01

    GRC research has led to the development of epoxy-clay nanocomposites with 60-70% lower gas permeability than the base epoxy resin. Filament wound carbon fiber reinforced tanks made with this nanocomposite had a five-fold lower helium leak rate than the corresponding tanks made without clay. More recent work has produced new composites with more than a 100-fold reduction in helium permeability. Use of these advanced, high barrier composites would eliminate the need for a liner in composite cryotanks, thereby simplifying construction and reducing propellant leakage. Aerogels are attractive materials for use as cryotank insulation because of their low density and low thermal conductivity. However, aerogels are fragile and have poor environmental stability, which have limited their use to certain applications in specialized environments (e.g., in certain types of nuclear reactors as Cerenkov radiation detectors, and as thermal insulators aboard space rovers on Mars). New GRC developed polymer crosslinked aerogels (X-Aerogels) retain the low density of conventional aerogels, but they demonstrate a 300-fold increase in their mechanical strength. Currently, our strongest materials combine a density of approx. 0.45 g/cc, a thermal conductivity of approx. 0.04 W/mK and a compressive strength of 185 MPa. Use of these novel aerogels as insulation materials/structural components in combination with the low permeability of epoxy-clay nanocomposites could significantly reduce cryotank weight and improve durability.

  15. Clay at Nili Fossae

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This image of the Nili Fossae region of Mars was compiled from separate images taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and the High-Resolution Imaging Science Experiment (HiRISE), two instruments on NASA's Mars Reconnaissance Orbiter. The images were taken at 0730 UTC (2:30 a.m. EDT) on Oct. 4, 2006, near 20.4 degrees north latitude, 78.5 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36 to 3.92 micrometers, and shows features as small as 18 meters (60 feet) across. HiRISE's image was taken in three colors, but its much higher resolution shows features as small as 30 centimeters (1 foot) across.

    CRISM's sister instrument on the Mars Express spacecraft, OMEGA, discovered that some of the most ancient regions of Mars are rich in clay minerals, formed when water altered the planet's volcanic rocks. From the OMEGA data it was unclear whether the clays formed at the surface during Mars' earliest history of if they formed at depth and were later exposed by impact craters or erosion of the overlying rocks. Clays are an indicator of wet, benign environments possibly suitable for biological processes, making Nili Fossae and comparable regions important targets for both CRISM and HiRISE.

    In this visualization of the combined data from the two instruments, the CRISM data were used to calculate the strengths of spectral absorption bands due to minerals present in the scene. The two major minerals detected by the instrument are olivine, a mineral characteristic of primitive igneous rocks, and clay. Areas rich in olivine are shown in red, and minerals rich in clay are shown in green. The derived colors were then overlayed on the HiRISE image.

    The area where the CRISM and HiRISE data overlap is shown at the upper left, and is about 5 kilometers (3 miles) across. The three boxes outlined in blue are enlarged to show how the different minerals in the scene match up with different landforms. In the image

  16. 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.

  17. Nondestructive evaluation of environmental barrier coatings in CFCC combustor liners.

    SciTech Connect

    Sun, J. G.; Benz, J.; Ellingson, W. A.; Kimmel, J. B.; Price, J. R.; Energy Technology; Solar Turbines, Inc

    2007-01-01

    Advanced combustor liners fabricated of SiC/SiC continuous fiber-reinforced ceramic composite (CFCC) and covered with environmental barrier coatings (EBCs) have been successfully tested in Solar Turbines Inc. field engines. The primary goal for the CFCC/EBC liners is to reach a 30,000-h lifetime. Because the EBCs, when applied on the hot surfaces of liners, protect the underlying CFCC from oxidation damage, their performance is critical in achieving the lifetime goal. To determine CFCC/EBC liner condition and assess operating damage, the liners were subjected to nondestructive evaluation (NDE) during various processing stages, as well as before and after the engine test. The NDE techniques included pulsed infrared thermal imaging, air-coupled ultrasonic scanning, and X-ray computerized tomography. It was found that EBC damage and spallation depend on the condition of the CFCC material. The NDE results and correlations with destructive examination are discussed.

  18. 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.

  19. Cementation of a polyethylene liner into a metal acetabular shell: a biomechanical study.

    PubMed

    Hofmann, Aaron A; Prince, Edward J; Drake, F Thurston; Hunt, Kenneth J

    2009-08-01

    Cementation of a liner into a well-fixed acetabular shell is common in revision hip arthroplasty. We compare the biomechanical strengths of cemented liners with standard locked liners. Fifty polyethylene liners were inserted into acetabular shells using the standard locking mechanism or 1 of 2 cement types then loaded to failure by torsion or lever-out testing. Lever-out testing showed that all cemented liners failed at similar loads to standard locked liners. With torsion testing, cemented liners failed at significantly higher loads than standard locked liners; roughening the liner increased load to failure. Cementation of an acetabular liner into a metal shell is safe and strong and a good alternative to metal shell replacement. Saw roughening of the polyethylene liner strengthens the poly-cement interface.

  20. 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.

  1. Re-Use of Clean Coal Technology By-Products in the Construction of Low Permeability Liners. Final report

    SciTech Connect

    Wolfe, William E.; Butalia, Tarunjit S.; Walker, Harold; Mitsch, William

    2005-07-15

    This final project report presents the results of a research program conducted at The Ohio State University from January 3, 2000 to June 30, 2005 to investigate the long-term use of stabilized flue gas desulfurization (FGD) materials in the construction of low permeability liners for ponds and wetlands. The objective of the research program was to establish long-term field-verified time-dependent relationships for the performance of liners constructed from stabilized FGD byproducts generated in Ohio. The project objective was accomplished with a coordinated program of testing and analyzing small-scale laboratory specimens under controlled conditions, mediumscale wetland experiments, and monitoring of a full-scale FGD-lined pond facility. Although the specific uses directly addressed by this report include liners for surface impoundments, the results presented in this study are also useful in other applications especially in the design of daily covers and liners for landfills, seepage cutoff walls and trenches, and for nutrient retention and pollution mitigation wetlands. The small-scale laboratory tests and monitoring of the full-scale FGD lined facility (capacity of one million gallons) shows that stabilized FGD materials can be used as low permeability liners in the construction of water and manure holding ponds. Actual long-term permeability coefficients in the range of 10-7 cm/sec (3 x 10-9 ft/sec) can be obtained in the field by compacting lime and fly ash enriched stabilized FGD materials. Leachate from the FGD material meets Ohio’s non-toxic criteria for coal combustion by-products, and for most potential contaminants the national primary and secondary drinking water standards are also met. The low permeability non-toxic FGD material investigated in this study poses very minimal risks, if any, for groundwater contamination. The FGD wetland experiments indicated no significant differences in phosphorus retention between the clay and FGD

  2. 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.

  3. Two-dimensional modeling of magnetically imploded liners

    SciTech Connect

    Atchison, W.L.; Bowers, R.L.; Brownell, J.H.; Lee, H.

    1996-11-01

    Magnetically imploded massive cylindrical liner drivers have been studied in two-dimensions for low, intermediate and high energy pulsed power systems. The simulations have been carried out using a resistive Eulerian magnetohydrodynamics computational model which includes material strength, and models the interactions between the imploding liner and the electrode walls. The computations simulate the generation of perturbations and their subsequent growth during the implosion. At low energies a solid liner remains in the plastic regime, reaching an inner cylindrical target with velocities of a few mm per {mu}s. At higher energies (where one-dimensional models predict implosion velocities of order 1 cm/{mu}s or more) resistive heating of the liner results in melting, and the effects of magnetically driven instabilities become important. We discuss the two-dimensional issues which arise in these systems. These include: the onset of perturbations associated with the motion of the liner along the electrodes; the growth of instabilities in liquid layers; and the suppression of instability growth during the implosion by maintaining a solid inner layer. Studies have been made of liners designed for the Pegasus capacitor bank facility (currents in the 5 - 12 MA regime), and for the Procyon high explosive system (currents in the 20 MA regime). This work focus on the design and performance of the first Pegasus composite megabar liner experiment.

  4. 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.

  5. 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.

  6. 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

  7. Nondestructive test to track pollutant transport into landfill liners

    NASA Astrophysics Data System (ADS)

    Bezzar, A.; Ghomari, F.

    2009-03-01

    Over the last decade, waste disposal has become a particularly sensitive issue in Algeria. New legislation concerning landfill liner design has been adopted. Traditional methods of landfill liner characterization involve soil sampling and chemical analysis, which are costly, destructive and time-consuming. New techniques are currently being investigated that aim to provide nondestructive liner characterisation. This paper details technical aspects associated with electrical conductivity measurements within landfill liners and presents experimental work to show the direct application of electrical techniques to track ionic movement through a sand bentonite liner under chemically induced flow. Samples of sand bentonite were mixed and compacted with NaCl electrolytes at different concentrations. The electrical conductivities of compacted specimens were measured with a two-electrode cell. The effects of frequency and electrolyte concentration on the conductivity measurement were explored. The relationship between the soil electrical conductivity and the NaCl electrolyte concentration in interstitial pore fluid was determined. The conductivity measurements were used to quantify the pore fluid concentration and effective diffusion coefficient of sand bentonite liners. It is concluded here that the electrical conductivity of compacted specimens depends mainly on the salt concentration in the pore fluid, and that this approach could therefore be used to track ionic movement through liners during diffusion.

  8. 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

  9. Liners for ion transport membrane systems

    DOEpatents

    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.

  10. A sensate liner for personnel monitoring applications

    NASA Astrophysics Data System (ADS)

    Lind, Eric J.; Jayaraman, Sundaresan; Park, Ms. Sungmee; Rajamanickam, Rangaswamy; Eisler, Robert, , Dr.; Burghart, Mr. George; McKee, Mr. Tony

    This program develops and demonstrates technologies useful for implementing a manageable cost effective systems approach to monitoring the medical condition of personnel by way of an instrumented uniform hereafter referred to as a Sensate Liner (SL). The SL consists of a form fitting garment which contains and interconnects sensing elements and devices to an electronics pack containing a processor and transmitter. The SL prototype requires fiber, textile, garment and sensor development. The SL textile consists of a mesh of electrically and optically conductive fibers integrated into the normal structure (woven or knitted) of fibers and yarns selected for comfort and durability. A suite of SL garment compatible embedded biological and physical sensors are then integrated into the SL. The initial SL sensor suite is selected to improve triage for combat casualties. Additional SL sensor concepts for medical monitoring will be discussed.

  11. A Sensate Liner for personnel monitoring applications.

    PubMed

    Lind, E J; Jayaraman, S; Park, S; Rajamanickam, R; Eisler, R; Burghart, G; McKee, T

    1998-01-01

    This program develops and demonstrates technologies useful for implementing a manageable cost effective systems approach to monitoring the medical condition of personnel by way of an instrumented uniform hereafter referred to as a Sensate Liner (SL). The SL consists of a form fitting garment which contains and interconnects sensing elements and devices to an electronics pack containing a processor and transmitter. The SL prototype requires fiber, textile, garment and sensor development. The SL textile consists of a mesh of electrically and optically conductive fibers integrated into the normal structure (woven or knitted) of fibers and yarns selected for comfort and durability. A suite of SL garment compatible embedded biological and physical sensors are then integrated into the SL. The initial SL sensor suite is selected to improve triage for combat casualties. Additional SL sensor concepts for medical monitoring will be discussed.

  12. A sensate liner for biomedical monitoring applications.

    PubMed

    Lind, E J; Jayaraman, S; Park, S; Rajamanickam, R; Eisler, R; Burghart, G; McKee, T

    1998-01-01

    This program develops and demonstrates technologies useful for implementing a manageable cost effective systems approach to monitoring the medical condition of personnel by way of an instrumented uniform hereafter referred to as a Sensate Liner (SL). The SL consists of a form fitting garment which contains and interconnects sensing elements and devices to an electronics pack containing a processor and transmitter. The SL prototype requires fiber, textile, garment and sensor development. The SL textile consists of a mesh of electrically and optically conductive fibers integrated into the normal structure (woven or knitted) of fibers and yarns selected for comfort and durability. A suite of SL garment compatible embedded biological and physical sensors are then integrated into the SL. The initial SL sensor suite is selected to improve triage for combat casualties. Additional SL sensor concepts for medical monitoring will be discussed.

  13. 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.

  14. Pegasus liner stability experiments: Diagnostics and experimental results

    SciTech Connect

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

    1998-12-31

    A series of experiments to compare imploding cylindrical liner performance with Magneto-HydroDynamic (MHD) modeling has been performed at the Los Alamos National Laboratory Pegasus capacitor bank. Several configurations of aluminum liners have been used; some with initial perturbations and some smooth. Instability growth resulting from the perturbations has been observed with high resolution. Load diagnostics included radial x-rays, fiber optic impact pins, and VISAR (Velocity Interferometer for a Surface of Any Reflector). Diagnostic results and comparisons for several liner stability (LS) experiments are presented.

  15. 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.

  16. Progress Report on Rotating Liquid Liner Implosion Experiment, 1 June to 31 December 1975.

    DTIC Science & Technology

    A critical question in the use of imploding liner flux compression for controlled fusion has been the stability of the inner surface of the liner ...To study the problem experimentally, the existing NRL Imploding Liner Facility was modified to allow the implosion of rotating liquid metal liners ...Rotational stabilization of lthe inner surface of a decelerating liquid sodium-potassium liner has been demonstrated, with excellent circularity of the

  17. Re-Use of Clean Coal Technology By-Products in the Construction of Low Permeability Liners. Final report, 10/1/1996 - 3/31/2000

    SciTech Connect

    Wolfe, William E.; Butalia, Tarunjit S.; Whitlach, Jr., E. Earl; Mitsch, William

    2000-12-31

    retention giving rise to the potential use of these materials as a liners for wastewater treatment wetlands. While plant growth was observed to be less vigorous for FGD lined wetland mesocosms compared to the control, the above and below ground biomass were not significantly different. Cost estimates for FGD liners compared favorably with clay liners for varying haul distances.

  18. 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.

  19. 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.

  20. Development of composite pressure vessels with nonmetallic liners

    NASA Astrophysics Data System (ADS)

    Murray, Con F.; Newhouse, Norman L.; Schimenti, John D.; Tiller, Dale B.

    1992-07-01

    Brunswick composites has developed metallic liners and composite cylinders for use in military and civilian aircraft, missiles, inflation systems and space applications. At present an all-composite pressurant tank is being developed for use in the natural gas vehicle (NGV). This tank uses a plastic liner of high density polyethylene (HDPE) as a leak-tight permeation barrier. Tank characteristics and testing are described. HDPE reduces cost, meets all space and missile pressurant tank requirements, and is readily availble. Test results indicate that an all-composite pressurant tank with an HDPE liner provides a tough, high cycle life, lightweight, environmentally stable pressurant tank with very low permeability. HDPE offers a viable, low cost alternative to conventional metal liners as well as many design advantages.

  1. Survey of Technologies for Monitoring Containment Liners and Covers

    EPA Pesticide Factsheets

    The report provides information on innovative long-term monitoring technologies to detect contaminant releases beneath a liner containment system and identify potential problems with the integrity of final containment covers.

  2. Liner protected carbon-carbon heat pipe concept

    NASA Astrophysics Data System (ADS)

    Rovang, Richard D.; Hunt, Maribeth E.

    1992-01-01

    A lightweight, high performance radiator concept using carbon-carbon heat pipes is being developed to support space nuclear power applications, specifically the SP-100 system. Carbon-carbon has been selected as an outer structural tube member because of its high temperature and strength characteristics; however, this material must be protected from the potassium heat pipe working fluid. A metallic liner approach is being taken to provide this fluid barrier. Feasibility issues associated with this approach include materials compatibility, fabricastion of the thin-walled liner, bonding the liner to the carbon-carbon tube, mismatch of coefficient of thermal expansion (CTE), carbon diffusion, and end cap closures. To resolve these issues, a series of test coupons have been fabricated and tested, assessing various liner materials, braze alloys, and substrate precursors. These tests will lead to a final heat pipe architecture, material selection, and component assembly.

  3. X-ray emission from LINERs observed with ASCA

    NASA Astrophysics Data System (ADS)

    Terashima, Y.

    We searched for evidence of the presence of AGN in LINERs using X-ray images and spectra up to 10 keV obtained with ASCA. We detected hard point-like nuclear sources with X-ray luminosities of 1040 - 1041 ergs s-1 from LINER 1s. Their Hα luminosities are positively correlated with the X-ray luminosities. These facts strongly support that these LINER 1s are ionized by low luminosity AGN. LINER 2s in the present sample have systematically lower X-ray to Hα luminosity ratio (LXLHα) suggesting that there exist other ionizing source or that the AGN is heavily obscured even at energies above 2 keV. X-ray properties of low luminosity AGNs are also discussed.

  4. 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.

  5. 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.

  6. Analytical Characterization of Natural Clay

    NASA Astrophysics Data System (ADS)

    El-Sheikhy, Refat; Al-Shamrani, Mosleh

    2010-10-01

    The current paper introduces the study of morphology and electronic microscopy characterization of one type of the smectite Saudi nano clay montmorillonite type. During the last decade, nanotechnology achieved a recognized progress in many fields based mainly on synthesized materials. Much attention is devoted to produce natural nano particles. It was found that the clay is one of the rare materials which have platelets of nano scale size. The nano clay minerals are found in different types. It is investigated that the nano clay minerals have super properties which can not be found in the other materials. The Kingdom of Saudi Arabia has many zones having different types of good nano clays. These nano clays are found in certain mixtures with other different materials such as Mg, Ca, Fe and others. By developing an innovated technique we could extract Saudi Arabian nano clay with high grade purity. The results are very interesting. The produced nano clay particles are with good quality and super properties. It can be used in many fields of nanocomposites.

  7. 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

  8. The performance of natural clay as a barrier to the diffusion of municipal solid waste landfill leachates.

    PubMed

    Cuevas, Jaime; Ruiz, Ana I; de Soto, Isabel S; Sevilla, Teresa; Procopio, Jesús R; Da Silva, Pilar; Gismera, Ma Jesús; Regadío, Mercedes; Sánchez Jiménez, Nicanor; Rodríguez Rastrero, Manuel; Leguey, Santiago

    2012-03-01

    In this paper, the diffusion of solutes in natural clay from a concentrated solution consisting primarily of ammonium, sodium and chloride ions at a pH level of 8 was studied and was based on an existing 20-year-old landfill. Contaminant transport through clay liners was predicted using transport and reaction geochemical codes to help explain the experimental data. The model predicted the chloride anion diffusion and cation exchange processes for three different experiments: (1) small-scale interactions in compacted clay, (2) 1:1 European Union (EU) Directive demonstration experiments (0.5-m-thick clay barrier), and (3) analysis of a bore hole with core recovery drilled in an old landfill located above a similar type of clay as that studied in (1) and (2). Orders of magnitude between 10(-10) and 10(-9) m(2) s(-1) were used for the apparent diffusion coefficient to fit the chloride profiles at the different scales; however, at larger space and time scales, diffusion was retarded due to the presence of more consolidated, non-mechanically disturbed clay materials at large depths in a natural clay-rock emplacement.

  9. 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.

  10. 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.

  11. Mineral resource of the Month: Clay

    USGS Publications Warehouse

    Virta, Robert L.

    2010-01-01

    Clays were one of the first mineral commodities used by people. Clay pottery has been found in archeological sites that are 12,000 years old, and clay figurines have been found in sites that are even older.

  12. 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.

  13. 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.

  14. Suppression of Helmholtz resonance using inside acoustic liner

    NASA Astrophysics Data System (ADS)

    Hong, Zhiliang; Dai, Xiwen; Zhou, Nianfa; Sun, Xiaofeng; Jing, Xiaodong

    2014-08-01

    When a Helmholtz resonator is exposed to grazing flow, an unstable shear layer at the opening can cause the occurrence of acoustic resonance under appropriate conditions. In this paper, in order to suppress the flow-induced resonance, the effects of inside acoustic liners placed on the side wall or the bottom of a Helmholtz resonator are investigated. Based on the one-dimensional sound propagation theory, the time domain impedance model of a Helmholtz resonator with inside acoustic liner is derived, and then combined with a discrete vortex model the resonant behavior of the resonator under grazing flow is simulated. Besides, an experiment is conducted to validate the present model, showing significant reduction of the peak sound pressure level achieved by the use of the side-wall liners. And the simulation results match reasonably well with the experimental data. The present results reveal that the inside acoustic liner can not only absorb the resonant sound pressure, but also suppress the fluctuation motion of the shear layer over the opening of the resonator. In all, the impact of the acoustic liners is to dampen the instability of the flow-acoustic coupled system. This demonstrates that it is a convenient and effective method for suppressing Helmholtz resonance by using inside acoustic liner.

  15. 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.

  16. How to select an effective waste pit liner

    SciTech Connect

    Hinds, A.A.; Legget, L.H.; Liao, A.

    1987-01-01

    This article reports that the use of earthen pits is widespread in the oil and gas industry. These pits are used to contain produced water as well as waste fluids and solids from drilling activities. The pits contain a myriad of metals, salts, minerals and organic compounds. Sometimes, a pit liner may be needed to ensure the integrity of the earthen pit. The pit liner should act as an impervious barrier between the contained fluids and soil or ground water outside the pit. It is imperative to construct the pit and liner to prevent leakage of pit contents and consequent potential contamination of the surrounding environment. In the United States, the construction of oilfield pits and the need for pit liners is typically governed by state oil and gas regulatory requirements. Standards for the construction and composition of pit liners vary considerably from state to state. Thus, when choosing a pit liner or constructing an oilfield waste pit, it is important to determine the legal requirements applicable in the state where the pit is located.

  17. Spherically symmetric simulation of plasma liner driven magnetoinertial fusion

    SciTech Connect

    Samulyak, Roman; Parks, Paul; Wu Lingling

    2010-09-15

    Spherically symmetric simulations of the implosion of plasma liners and compression of plasma targets in the concept of the plasma jet driven magnetoinertial fusion have been performed using the method of front tracking. The cases of single deuterium and xenon liners and double layer deuterium-xenon liners compressing various deuterium-tritium targets have been investigated, optimized for maximum fusion energy gains, and compared with theoretical predictions and scaling laws of [P. Parks, Phys. Plasmas 15, 062506 (2008)]. In agreement with the theory, the fusion gain was significantly below unity for deuterium-tritium targets compressed by Mach 60 deuterium liners. The most optimal setup for a given chamber size contained a target with the initial radius of 20 cm compressed by a 10 cm thick, Mach 60 xenon liner, achieving a fusion energy gain of 10 with 10 GJ fusion yield. Simulations also showed that composite deuterium-xenon liners reduce the energy gain due to lower target compression rates. The effect of heating of targets by alpha particles on the fusion energy gain has also been investigated.

  18. 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.

  19. Clay energetics in chemical evolution

    NASA Technical Reports Server (NTRS)

    Coyne, L. M.

    1986-01-01

    Clays have been implicated in the origin of terrestrial life since the 1950's. Originally they were considered agents which aid in selecting, concentrating and promoting oligomerization of the organic monomeric substituents of cellular life forms. However, more recently, it has been suggested that minerals, with particular emphasis on clays, may have played a yet more fundamental role. It has been suggested that clays are prototypic life forms in themselves and that they served as a template which directed the self-assembly of cellular life. If the clay-life theory is to have other than conceptual credibility, clays must be shown by experiment to execute the operations of cellular life, not only individually, but also in a sufficiently concerted manner as to produce some semblance of the functional attributes of living cells. Current studies are focussed on the ability of clays to absorb, store and transfer energy under plausible prebiotic conditions and to use this energy to drive chemistry of prebiotic relevance. Conclusions of the work are applicable to the role of clays either as substrates for organic chemistry, or in fueling their own life-mimetic processes.

  20. 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.

  1. Clay and pillard clay membranes: Synthesis, characterization and transport properties

    NASA Astrophysics Data System (ADS)

    Vercauteren, Sven

    In this work, the preparation and characterization of ceramic multilayer membranes with an Alsb2Osb3-pillared montmorillonite (Al-PILC) and a Laponite separating layer have been studied. Al-PILC is a pillared clay prepared by intercalation of polyoxo cations of aluminium between the montmorillonite clay sheets, followed by a thermal treatment (400sp°C) to obtain rigid oxide pillars. The free spacing between the clay plates is about 0.8 nm. Laponite is a synthetic clay with a pore structure formed by the stacking of very small clay plates. To deposit an Al-PILC top layer on a macro- or mesoporous aluminiumoxide support membrane, two preparation routes were considered. According to the standard preparation route of a pillared clay, the easiest way is to use a suspension of clay mixed with the pillaring solution in which the support membrane is dipped. However, it is not possible to deposit uniform and crack-free top layers in this way because of the formation of unstable suspensions. A second preparation route is based on an indirect pillaring procedure. By dipping a support membrane in a stable clay suspension, a thin clay film is deposited in a first step. Pillaring is achieved via immersion of the supported clay film in the pillaring solution in a second step. After a washing procedure, the membrane is dried and calcined at 400sp°C. Laponite membranes were simply prepared by dipping a support membrane in a suspension of this synthetic clay in water. Afterwards a drying at room temperature and a calcination at 400 ar 500sp°C is performed. Both membrane types were tested for gas separation and pervaporation purposes. Transport of permanent gases (He, N2) occurs by means of Knudsen diffusion. Diffusion is kinetically controlled and for a binary mixture, the maximum separation factor is determined by the difference in molecular weight of both components. From pervaporation experiments with water/alcohol mixtures it was found that Al-PILC membranes can be used for

  2. Scanning electron microscopy of clays and clay minerals

    USGS Publications Warehouse

    Bohor, B.F.; Hughes, R.E.

    1971-01-01

    The scanning electron microscope (SEM) proves to be ideally suited for studying the configuration, texture, and fabric of clay samples. Growth mechanics of crystalline units-interpenetration and interlocking of crystallites, crystal habits, twinning, helical growth, and topotaxis-also are uniquely revealed by the SEM. Authigenic kaolins make up the bulk of the examples because their larger crystallite size, better crystallinity, and open texture make them more suited to examination by the SEM than most other clay mineral types. ?? 1971.

  3. GuideLiner Balloon Assisted Tracking (GBAT): A New Addition to the Interventional Toolbox

    PubMed Central

    Elbarouni, Basem; Moussa, Motaz; Kass, Malek; Toleva, Olga; Vo, Minh

    2016-01-01

    The use of guide extension catheters, such as GuideLiner, allows for increased guide support and facilitates device delivery in tortuous vessels. In cases which the GuideLiner catheter cannot be advanced even with balloon anchoring technique, we inflate a noncompliant balloon protruding from the GuideLiner catheter at nominal pressure and both the GuideLiner and the balloon are advanced over the coronary guidewire through the tortuous segments. This technique can be applied to 5.5 Fr., 6 Fr., and 7 Fr. GuideLiner catheters. This technique is termed GuideLiner Balloon Assisted Tracking (GBAT). PMID:28116176

  4. Tool for Taking Clay Impressions

    NASA Technical Reports Server (NTRS)

    Duncan, R. S.

    1984-01-01

    Clay impression of small parts taken with tool consisting of hollow tube closed at one end. Slots at other end admit part short distance into tube. Impression used to make silicone rubber mold for examination.

  5. 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

  6. 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.

  7. Demonstration of a wireless, self-powered, electroacoustic liner system.

    PubMed

    Phipps, Alex; Liu, Fei; Cattafesta, Louis; Sheplak, Mark; Nishida, Toshikazu

    2009-02-01

    This paper demonstrates the system operation of a self-powered active liner for the suppression of aircraft engine noise. The fundamental element of the active liner system is an electromechanical Helmholtz resonator (EMHR), which consists of a Helmholtz resonator with one of its rigid walls replaced with a circular piezoceramic composite plate. For this system demonstration, two EMHR elements are used, one for acoustic impedance tuning and one for energy harvesting. The EMHR used for acoustic impedance tuning is shunted with a variable resistive load, while the EMHR used for energy harvesting is shunted to a flyback power converter and storage element. The desired acoustic impedance conditions are determined externally, and wirelessly transmitted to the liner system. The power for the receiver and the impedance tuning circuitry in the liner are supplied by the harvested energy. Tuning of the active liner is demonstrated at three different sound pressure levels (148, 151, and 153 dB) in order to show the robustness of the energy harvesting and storage system. An acoustic tuning range of approximately 200 Hz is demonstrated for each of the three available power levels.

  8. 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

  9. Scattering of acoustic duct modes by axial liner splices

    NASA Astrophysics Data System (ADS)

    Tam, Christopher K. W.; Ju, Hongbin; Chien, Eugene W.

    2008-03-01

    Recent engine test data and results of computational analysis show that the engine inlet acoustic liner splices have a significant impact on aircraft flight noise certification and cabin noise levels. The phenomenon of scattering of acoustic duct modes by axial liner splices is investigated. Previous studies, invariably, follow the frequency-domain approach. The present study, however, uses the time-domain approach. It is demonstrated that time-domain computation yields results that are in close agreement with frequency-domain results. The scattering phenomenon under consideration is very complex. This study concentrates on the effects of four parameters. They are the width of the splices, the frequency of the incident duct mode, the number of splices and the length of splices. Based on the computed results, the conditions under which scattered wave modes would significantly increase the intensity of transmitted waves are identified. It is also found that surface scattering by liner splices has the tendency to distribute energy equally to all the cut-on scattered azimuthal modes. On the other hand, for each scattered azimuthal mode, the high-order cut-on radial mode, generally, has the highest intensity. Moreover, scattering by liner splices is a local phenomenon. It is confined primarily to an area of the duct adjacent to the junction between the hard wall near the fan face and the spliced liner.

  10. 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

  11. 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).

  12. 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.

  13. Metal liner-driven quasi-isentropic compression of deuterium

    SciTech Connect

    Weinwurm, Marcus; Bland, Simon N.; Chittenden, Jeremy P.

    2013-09-15

    Properties of degenerate hydrogen and deuterium (D) at pressures of the order of terapascals are of key interest to Planetary Science and Inertial Confinement Fusion. In order to recreate these conditions in the laboratory, we present a scheme, where a metal liner drives a cylindrically convergent quasi-isentropic compression in a D fill. We first determined an external pressure history for driving a self-similar implosion of a D shell from a fictitious flow simulation [D. S. Clark and M. Tabak, Nucl. Fusion 47, 1147 (2007)]. Then, it is shown that this D implosion can be recreated inside a beryllium liner by shaping the current pulse. For a peak current of 10.8 MA cold and nearly isochoric D is assembled at around 12 500 kg/m{sup 3}. Finally, our two-dimensional Gorgon simulations show the robustness of the implosion method to the magneto-Rayleigh-Taylor instability when using a sufficiently thick liner.

  14. 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.

  15. 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

  16. 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.

  17. Five synthetic rubber pond liners protect against leakage and weather

    SciTech Connect

    Weinreich, G.; Hofsess, R.; Toy, D.A.

    1987-03-01

    More than 137 million cu ft of pipeline quality gas is produced daily at the Great Plains Coal Gasification Project in Beulah, ND. The facility is the only commercial plant in the US which produces gaseous and liquid fuels from low-grade coal. The plant needs to recycle and reuse 100% of the organic process wastewater, requiring a complicated treatment system of cooling towers, evaporators, a liquid waste incinerator and other units, each of which has its own surge pond. In total, the plant has five surge ponds which hold near 80 million gallons. To prevent the seepage of wastewater from the surge ponds into the ground water, a liner material was needed that would fulfill several design criteria. The liner had to be resistant to degradation caused by a very wide range of temperatures and it had to have a low coefficient of expansion. Resistance to both organic and inorganic chemical substances was another key requirement. Finally, the liner material needed to be easy to seam during field installation. An elastomeric membrane liner using the synthetic rubber and reinforcing polyester scrim best met the plant's requirements. One of the primary reasons for selecting synthetic rubber was its low coefficient of expansion. Extreme seasonal weather conditions, with temperatures ranging from below zero in the winter to over 100/sup 0/F in the summer, are common in North Dakota. And because the level of wastewater in the ponds constantly varies, a liner is frequently exposed to the elements. Overall, the synthetic rubber pond liners have performed through extreme weather conditions and have proven to be a cost-effective solution to wastewater storage at the gasification project.

  18. A Prospective Randomized Crossover Study on the Comparison of Cotton Versus Waterproof Cast Liners

    PubMed Central

    Guillen, Philip T.; Fuller, Corey B.; Riedel, Barth B.; Wongworawat, Montri D.

    2016-01-01

    Background: Many fractures are treated with casting which can cause complications likely from inability to wash the extremity. Gore-Tex-based waterproof cast liner has been compared with cotton liner and shown to be superior in physician and patient scoring but also has high cost and difficult application. The purpose of this study is to compare newer generation waterproof liners with traditional cotton liner. It is the first study to compare this new waterproof liner and cotton liner in a crossover model, allowing patients to swim in the pool with the cast. Methods: Twenty patients (ages 3-30) with upper extremity injuries were randomized to waterproof-liner or cotton-liner casts made of fiberglass. Patients would switch cast liners halfway between their treatments to fulfill crossover criteria. All fractures were within a 2-week period from original incident. At each clinic visit, patients evaluated comfort parameters through questionnaires, and physicians rated skin condition. Patients were also asked which cast liner they preferred at the end of the study. Results: There were no unscheduled cast changes. The waterproof-liner group had better scores for odor (P = .041), sweat (P = .016), and overall physician-rated score (P = .038). There was no significant difference in other patient-rated parameters. Seventy-five percent of patients preferred waterproof casting to the cotton liner. Conclusions: This new waterproof cast liner, compared with cotton cast liner, had better odor, sweat, and overall physician scores. The waterproof liners allow patients to rinse casts daily, and the majority of patients prefer waterproof to cotton liner. PMID:27418889

  19. 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.

  20. Stresses in polyethylene liners in a semiconstrained ankle prosthesis.

    PubMed

    Miller, M C; Smolinski, P; Conti, S; Galik, K

    2004-10-01

    A finite element model of a semiconstrained ankle implant with the tibia and fibula was constructed so that the stresses in the polyethylene liner could be computed. Two different widths of talar components were studied and proximal boundary conditions were computed from an inverse process providing a load of five times body weight appropriately distributed across the osseous structures. von Mises stresses indicated small regions of localized yielding and contact stresses that were similar to those in acetabular cup liners. A wider talar component with 36% more surface area reduced contact stress and von Mises stresses at the center of the polyethylene component by 17%.

  1. 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.

  2. 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.

  3. 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.

  4. Diagnosing magnetized liner inertial fusion experiments on Z

    DOE PAGES

    Hansen, Stephanie B.; Gomez, Matthew R.; Sefkow, Adam B.; ...

    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.

  5. Molding Helmet Liners from Nylon Cloth Made from 1050 Denier Type 700 Nylon Yarns

    DTIC Science & Technology

    Helmet liners were satisfactorily molded from 14 ounce, 2 x 2 basket- weave nylon fabric made of 1050 denier, 168 filaments, 3 to 4 Z turns per inch...type 700 nylon yarn. These helmets liners satisfied the autoclave and the ballistics resistant requirements of Military Specification MIL-L-41800, Liner , Soldier’s Steel Helmet, 1 May 1961.

  6. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., 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 pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least...

  7. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., 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 pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least...

  8. 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 pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least...

  9. 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

    ... (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 stock... status for activity related to the manufacturing and distribution of aluminum foil liner stock...

  10. 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.

  11. Atom exchange between aqueous Fe(II) and structural Fe in clay minerals.

    PubMed

    Neumann, Anke; Wu, Lingling; Li, Weiqiang; Beard, Brian L; Johnson, Clark M; Rosso, Kevin M; Frierdich, Andrew J; Scherer, Michelle M

    2015-03-03

    Due to their stability toward reductive dissolution, Fe-bearing clay minerals are viewed as a renewable source of Fe redox activity in diverse environments. Recent findings of interfacial electron transfer between aqueous Fe(II) and structural Fe in clay minerals and electron conduction in octahedral sheets of nontronite, however, raise the question whether Fe interaction with clay minerals is more dynamic than previously thought. Here, we use an enriched isotope tracer approach to simultaneously trace Fe atom movement from the aqueous phase to the solid ((57)Fe) and from the solid into the aqueous phase ((56)Fe). Over 6 months, we observed a significant decrease in aqueous (57)Fe isotope fraction, with a fast initial decrease which slowed after 3 days and stabilized after about 50 days. For the aqueous (56)Fe isotope fraction, we observed a similar but opposite trend, indicating that Fe atom movement had occurred in both directions: from the aqueous phase into the solid and from the solid into aqueous phase. We calculated that 5-20% of structural Fe in clay minerals NAu-1, NAu-2, and SWa-1 exchanged with aqueous Fe(II), which significantly exceeds the Fe atom layer exposed directly to solution. Calculations based on electron-hopping rates in nontronite suggest that the bulk conduction mechanism previously demonstrated for hematite1 and suggested as an explanation for the significant Fe atom exchange observed in goethite2 may be a plausible mechanism for Fe atom exchange in Fe-bearing clay minerals. Our finding of 5-20% Fe atom exchange in clay minerals indicates that we need to rethink how Fe mobility affects the macroscopic properties of Fe-bearing phyllosilicates and its role in Fe biogeochemical cycling, as well as its use in a variety of engineered applications, such as landfill liners and nuclear repositories.

  12. Clay minerals for advanced ceramics

    SciTech Connect

    Murray, H.H. )

    1989-11-01

    The author describes new and improved beneficiation techniques available to allow the production of clay minerals of exceptionally high purity. This is particularly true for kaolins and smectites. Wet processing techniques include particle size separation, high intensity magnetic separation, chemical leaching, flotation, and selective flocculation. The blending of clay minerals with other minerals provides opportunities to make special ceramic materials such as cordierite and other minerals that have very special ceramic properties including low heat expansion, high fired strength, low absorption, and other desired qualities.

  13. Boron enrichment in martian clay.

    PubMed

    Stephenson, James D; Hallis, Lydia J; Nagashima, Kazuhide; Freeland, Stephen J

    2013-01-01

    We have detected a concentration of boron in martian clay far in excess of that in any previously reported extra-terrestrial object. This enrichment indicates that the chemistry necessary for the formation of ribose, a key component of RNA, could have existed on Mars since the formation of early clay deposits, contemporary to the emergence of life on Earth. Given the greater similarity of Earth and Mars early in their geological history, and the extensive disruption of Earth's earliest mineralogy by plate tectonics, we suggest that the conditions for prebiotic ribose synthesis may be better understood by further Mars exploration.

  14. Boron Enrichment in Martian Clay

    PubMed Central

    Nagashima, Kazuhide; Freeland, Stephen J.

    2013-01-01

    We have detected a concentration of boron in martian clay far in excess of that in any previously reported extra-terrestrial object. This enrichment indicates that the chemistry necessary for the formation of ribose, a key component of RNA, could have existed on Mars since the formation of early clay deposits, contemporary to the emergence of life on Earth. Given the greater similarity of Earth and Mars early in their geological history, and the extensive disruption of Earth's earliest mineralogy by plate tectonics, we suggest that the conditions for prebiotic ribose synthesis may be better understood by further Mars exploration. PMID:23762242

  15. 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.

  16. Auto-magnetizing liners for magnetized inertial fusion

    NASA Astrophysics Data System (ADS)

    Slutz, S. A.; Jennings, C. A.; Awe, T. J.; Shipley, G. A.; Hutsel, B. T.; Lamppa, D. C.

    2017-01-01

    The MagLIF (Magnetized Liner Inertial Fusion) concept [Slutz et al., Phys. Plasmas 17, 056303 (2010)] has demonstrated fusion-relevant plasma conditions [Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z accelerator using external field coils to magnetize the fuel before compression. We present a novel concept (AutoMag), which uses a composite liner with helical conduction paths separated by insulating material to provide fuel magnetization from the early part of the drive current, which by design rises slowly enough to avoid electrical breakdown of the insulators. Once the magnetization field is established, the drive current rises more quickly, which causes the insulators to break down allowing the drive current to follow an axial path and implode the liner in the conventional z-pinch manner. There are two important advantages to AutoMag over external field coils for the operation of MagLIF. Low inductance magnetically insulated power feeds can be used to increase the drive current, and AutoMag does not interfere with diagnostic access. Also, AutoMag enables a pathway to energy applications for MagLIF, since expensive field coils will not be damaged each shot. Finally, it should be possible to generate Field Reversed Configurations (FRC) by using both external field coils and AutoMag in opposite polarities. This would provide a means to studying FRC liner implosions on the 100 ns time scale.

  17. Demonstration test of burner liner strain measurement systems: Interim results

    NASA Technical Reports Server (NTRS)

    Stetson, K. A.; Grant, H. P.

    1983-01-01

    Work is in progress to demonstrate two techniques for static strain measurements on a jet engine burner liner. Measurements are being made with a set of resistance strain gages made from Kanthal A-1 wire and via heterodyne speckle photogrammetry. The background of the program is presented along with current results.

  18. 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.

  19. Hydrodynamic Liner Experiments Using the Ranchero Flux Compression Generator System

    SciTech Connect

    Goforth, J.H.; Atchison, W.L.; Fowler, C.M.; Lopez, E.A.; Oona, H.; Tasker, D.G.; King, J.C.; Herrera, D.H.; Torres, D.T.; Sena, F.C.; McGuire, J.A.; Reinovsky, R.E.; Stokes, J.L.; Tabaka, L.J.; Garcia, O.F.; Faehl, R.J.; Lindemuth, I.R.; Keinigs, R.K.; Broste, B.

    1998-10-18

    The authors have developed a system for driving hydrodynamic liners at currents approaching 30 MA. Their 43 cm module will deliver currents of interest, and when fully developed, the 1.4 m module will allow similar currents with more total system inductance. With these systems they can perform interesting physics experiments and support the Atlas development effort.

  20. 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.

  1. 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.

  2. Auto-magnetizing liners for magnetized inertial fusion

    DOE PAGES

    Slutz, S. A.; Jennings, C. A.; Awe, T. J.; ...

    2017-01-20

    Here, the MagLIF (Magnetized Liner Inertial Fusion) concept has demonstrated fusion-relevant plasma conditions on the Z accelerator using external field coils to magnetize the fuel before compression. We present a novel concept (AutoMag), which uses a composite liner with helical conduction paths separated by insulating material to provide fuel magnetization from the early part of the drive current, which by design rises slowly enough to avoid electrical breakdown of the insulators. Once the magnetization field is established, the drive current rises more quickly, which causes the insulators to break down allowing the drive current to follow an axial path andmore » implode the liner in the conventional z-pinch manner. There are two important advantages to AutoMag over external field coils for the operation of MagLIF. Low inductance magnetically insulated power feeds can be used to increase the drive current, and AutoMag does not interfere with diagnostic access. Also, AutoMag enables a pathway to energy applications for MagLIF, since expensive field coils will not be damaged each shot. Finally, it should be possible to generate Field Reversed Configurations (FRC) by using both external field coils and AutoMag in opposite polarities. This would provide a means to studying FRC liner implosions on the 100 ns time scale.« less

  3. Examination of resistivity issues in solid liner z-pinches

    SciTech Connect

    Atchison, W.L.; Faehl, R.J.; Reinovsky, R.E.

    1999-07-01

    Experiments being conducted at the Los Alamos National lab Pegasus facility are examining driving an aluminum liner with a pulsed magnetic field. The Pegasus facility provides a current of 5 to 8 Mega-amps to compress a cylindrical liner. Liners of various size and thickness are used, depending on the specific experimental objectives. In several of these experiments, a B-dot probe has been used to measure the field diffused through the liners. This data has been compared to predictions of field penetrations using numerical simulations. These predictions were made with a 2D Eulerian and a 1D Lagrangian MHD code. The simulations were made with a wide variety of resistivity models including both SESAME tabular values and analytic models. the results of these comparisons show that the behavior of aluminum in the region from a few tenths of a eV to 1eV and densities from about .2 to 3.0 g/cc is not reproduced well. While this is understandable based on the back of conclusive data in the region, these experiments confirm the in-applicability of extrapolating existing models into this region where phase changes are drastically changing the behavior.

  4. Development of variable-rate sprayer for nursery liner applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sensor-guided application technologies are needed to achieve constant spray deposition for the rapid growth of nursery liner trees during a growing season. An experimental real-time variable-rate sprayer that implemented 20 Hz ultrasonic sensors and pulse width modulation (PWM) solenoid valve-contro...

  5. 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.

  6. 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 ...

  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. 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 872.3250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... prepared cavity before insertion of restorative material, such as amalgam, to protect the pulp of a...

  9. 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... prepared cavity before insertion of restorative material, such as amalgam, to protect the pulp of a...

  10. 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 872.3250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... prepared cavity before insertion of restorative material, such as amalgam, to protect the pulp of a...

  11. 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 872.3250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... prepared cavity before insertion of restorative material, such as amalgam, to protect the pulp of a...

  12. 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.

  13. 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.

  14. 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.

  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. 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.

  17. 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.

  18. Prosthetic liners for lower limb amputees: a review of the literature.

    PubMed

    Klute, Glenn K; Glaister, Brian C; Berge, Jocelyn S

    2010-06-01

    Prosthetic liners exist to improve amputee safety and comfort by adding a cushioning layer between the residual limb and the prosthetic socket. Many choices in liner technology are available, and clinicians often rely on personal intuition and experience to choose which liners are appropriate for which patients. The purpose of this study was to examine the literature to find what scientific evidence exists to inform prescription practices. 'Prosthetic liner' was used as a search term in the Web of Science and PubMed research databases. Fourteen scientific articles met the eligibility criteria and are discussed in this review. The results of this review suggest that there is little scientific evidence to inform prosthetic liner prescription practices. Liner material properties have been well-studied, but their influence on in vivo performance is not well understood. Understanding liner effect on function would be an area of great usefulness.

  19. Biodegradable Pectin/clay Aerogels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodegradable, foamlike materials based on renewable pectin and sodium montmorillonite clay were fabricated through a simple, environmentally friendly freeze-drying process. Addition of multivalent cations (Ca2+ and Al3+) resulted in apparent crosslinking of the polymer, and enhancement of aerogel p...

  20. ADSORPTION OF SURFACTANT ON CLAYS

    EPA Science Inventory

    Surfactants used to enhance remediation of soils by soil washing are often lost in the process. Neither the amount nor the cause of this loss is known. It is assumed that clays present in the soil are responsible for the loss of the surfactant. In this papere, adsorption prope...

  1. Picasso Masks: Cubism in Clay

    ERIC Educational Resources Information Center

    Daddino, Michelle

    2010-01-01

    This article describes an art project developed by the author which provides a way to further the children's understanding of Picasso's Cubism style in 3-D. Through this project, upper-elementary students learn a bit about the life and art of Picasso as they gain a firm understanding of the style of art known as Cubism, and apply clay techniques…

  2. Multifunctional epoxy composites with natural Moroccan clays

    NASA Astrophysics Data System (ADS)

    Monsif, M.; Zerouale, A.; Kandri, N. Idrissi; Allali, F.; Sgarbossa, P.; Bartolozzi, A.; Tamburini, S.; Bertani, R.

    2016-05-01

    Two natural Moroccan clays, here firstly completely characterized, have been used as fillers without modification in epoxy composites. Mechanical properties resulted to be improved and a significant antibacterial activity is exhibited by the epoxy composite containing the C2 clay.

  3. Stools - pale or clay-colored

    MedlinePlus

    ... gov/ency/article/003129.htm Stools - pale or clay-colored To use the sharing features on this page, please enable JavaScript. Stools that are pale, clay, or putty-colored may be due to problems ...

  4. Clay complexes support HDS catalyst.

    SciTech Connect

    Marshall, C. L.; Carrado, K.; Chemical Engineering

    2000-01-01

    Hydroprocessing represents a crucial component of petroleum refining operations both in terms of environmental and economic considerations. Regulations concerning maximum amount of sulfur content of gasoline and emissions of sulfur-oxide compounds upon combustion are becoming more and more stringent. One 1994-2000 focus of Argonne National Laboratory (ANL) has been the development of catalysts for hydrodesulfurization (HDS). Typical HDS catalysts are comprised of Co-Mo sulfides or Ni-Mo sulfides on an alumina support. Modification of the pore structure of the support has generated great attention among researchers. Most desulfurization test reactions have used dibenzothiophene (DBT) as the model compound to test various configurations of support material with Co-Mo-S and Ni-Mo-S catalysts. In this testing, the desired product would be biphenyl and hydrogen sulfide (H{sub 2}S). A competing reaction creates cyclohexylbenzene by saturating one aromatic ring prior to desulfurization. Ring saturation requires more costly hydrogen and is not desirable. Fortunately, a more effective catalyst for adding hydrogen at the sulfur site with hydrogenating the aromatic rings has been found. However, this has only been tested on DBT. HDS uses various types of catalysts to add hydrogen to reduce unwanted sulfur compounds. Typically this requires expensive, high-pressure, high-temperature equipment to produce the environmentally friendly low-sulfur fuels. ANL scientists identified several new desulfurization catalysts with improved HDS activity and selectivity. From these new catalysts, it may be possible to achieve HDS processing at lower temperature and pressure. The catalysts used for HDS at ANL are various clay complexes. Natural clays have a history of use in the hydroprocessing industry since they are abundant and inexpensive. ANL's approach is to create synthetic organo-clay complexes (SOCC). An advantage of SOCCs is that the pore size and distribution can be controlled by

  5. Mineral resource of the month: clays

    USGS Publications Warehouse

    Virta, Robert

    2004-01-01

    Clays represent one of the largest mineral commodities in the world in terms of mineral and rock production and use. Many people, however, do not recognize that clays are used in an amazingly wide variety of applications. Use continues to increase worldwide as populations and their associated needs increase. Robert Virta, clay and shale commodity specialist for the U.S. Geological Survey, has prepared the following information about clays.

  6. 21 CFR 186.1256 - Clay (kaolin).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Clay (kaolin). 186.1256 Section 186.1256 Food and... Substances Affirmed as GRAS § 186.1256 Clay (kaolin). (a) Clay (kaolin) Al2O3.2SiO2.nH2O, Cas Reg. No. 1332-58-7) consists of hydrated aluminum silicate. The commercial products of clay (kaolin)...

  7. 21 CFR 186.1256 - Clay (kaolin).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Clay (kaolin). 186.1256 Section 186.1256 Food and... Substances Affirmed as GRAS § 186.1256 Clay (kaolin). (a) Clay (kaolin) Al2O3.2SiO2.nH2O, Cas Reg. No. 1332-58-7) consists of hydrated aluminum silicate. The commercial products of clay (kaolin)...

  8. 21 CFR 186.1256 - Clay (kaolin).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Clay (kaolin). 186.1256 Section 186.1256 Food and... Substances Affirmed as GRAS § 186.1256 Clay (kaolin). (a) Clay (kaolin) Al2O3.2SiO2.nH2O, Cas Reg. No. 1332-58-7) consists of hydrated aluminum silicate. The commercial products of clay (kaolin)...

  9. 21 CFR 186.1256 - Clay (kaolin).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Clay (kaolin). 186.1256 Section 186.1256 Food and....1256 Clay (kaolin). (a) Clay (kaolin) Al2O3.2SiO2.nH2O, Cas Reg. No. 1332-58-7) consists of hydrated aluminum silicate. The commercial products of clay (kaolin) contain varying quantities of alkalies...

  10. 21 CFR 186.1256 - Clay (kaolin).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Clay (kaolin). 186.1256 Section 186.1256 Food and... Substances Affirmed as GRAS § 186.1256 Clay (kaolin). (a) Clay (kaolin) Al2O3.2SiO2.nH2O, Cas Reg. No. 1332-58-7) consists of hydrated aluminum silicate. The commercial products of clay (kaolin)...

  11. 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

  12. Clay & Children: More than Making Pots.

    ERIC Educational Resources Information Center

    Kolbe, Ursula

    1997-01-01

    Working with clay enables young children to express, explore, and communicate their feelings and ideas. This resource booklet for early childhood practitioners and it promotes the clay table as a special place for shared discoveries, social interaction, and discussion. The booklet provides a glossary of terms used in clay work, as well as reasons…

  13. Clay Cuffman: A Cool, Calm, Relaxed Guy

    ERIC Educational Resources Information Center

    Booth, Gina

    2010-01-01

    This article describes Clay Cuffman, a simple clay-sculpture project that requires two or three sessions, and works for students from the upper-elementary level through high school. It takes about 1.5 pounds of clay per student--about the size of a small grapefruit. The Cuffman project is a great way for upper-elementary through high-school…

  14. The systems containing clays and clay minerals from modified drug release: a review.

    PubMed

    Rodrigues, Luís Alberto de Sousa; Figueiras, Ana; Veiga, Francisco; de Freitas, Rivelilson Mendes; Nunes, Lívio César Cunha; da Silva Filho, Edson Cavalcanti; da Silva Leite, Cleide Maria

    2013-03-01

    Clays are materials commonly used in the pharmaceutical industry, either as ingredients or as active ingredients. It was observed that when they are administered concurrently, they may interact with drugs reducing their absorption. Therefore, such interactions can be used to achieve technological and biopharmaceutical advantages, regarding the control of release. This review summarizes bibliographic (articles) and technological (patents) information on the use of systems containing clays and clay minerals in modified drug delivery. In this area, formulations such natural clay, commercial clay, synthetic clay, composites clay-polymers, nanocomposites clay-polymers, films and hidrogels composites clay-polymers are used to slow/extend or vectorize the release of drugs and consequently they increase their bioavailability. Finally, this review summarizes the fields of technology and biopharmaceutical applications, where clays are applied.

  15. Modeling Radionuclide Transport in Clays

    SciTech Connect

    Zheng, Liange; Li, Lianchong; Rutqvist, Jonny; Liu, Hui -Hai; Birkholzer, Jens

    2012-05-01

    Clay/shale has been considered as potential host rock for geological disposal of high-level nuclear waste throughout the world, because of its low permeability, low diffusion coefficient, high retention capacity for radionuclides, and capability to self-seal fractures induced by tunnel excavation. For example, Callovo-Oxfordian argillites at the Bure site, France (Fouche et al., 2004), Toarcian argillites at the Tournemire site, France (Patriarche et al., 2004), Opalinus Clay at the Mont Terri site, Switzerland (Meier et al., 2000), and Boom clay at the Mol site, Belgium (Barnichon and Volckaert, 2003) have all been under intensive scientific investigation (at both field and laboratory scales) for understanding a variety of rock properties and their relationships to flow and transport processes associated with geological disposal of nuclear waste. Clay/shale formations may be generally classified as indurated or plastic clays (Tsang and Hudson, 2010). The latter (including Boom clay) is a softer material without high cohesion; its deformation is dominantly plastic. During the lifespan of a clay repository, the repository performance is affected by complex thermal, hydrogeological, mechanical, chemical (THMC) processes, such as heat release due to radionuclide decay, multiphase flow, formation of damage zones, radionuclide transport, waste dissolution, and chemical reactions. All these processes are related to each other. An in-depth understanding of these coupled processes is critical for the performance assessment (PA) of the repository. These coupled processes may affect radionuclide transport by changing transport paths (e.g., formation and evolution of excavation damaged zone (EDZ)) and altering flow, mineral, and mechanical properties that are related to radionuclide transport. While radionuclide transport in clay formation has been studied using laboratory tests (e,g, Appelo et al. 2010, Garcia-Gutierrez et al., 2008, Maes et al., 2008), short-term field

  16. 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

  17. Evaluation of Novel Liner Concepts for Fan and Airframe Noise Reduction

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Howerton, B. M.

    2016-01-01

    This paper presents a review of four novel liner concepts: soft vanes, over-the-rotor liners, external liners, and flap side-edge liners. A number of similarities in the design and evaluation of these concepts emerged during these investigations. Since these were the first attempts to study these particular liner concepts, there was limited information to guide the design process. In all cases, the target frequencies (or frequency range) were known, but the optimum acoustic impedance and optimum liner placement were typically not known. For these cases, the maximum available surface was used and a c-impedance was targeted based on the assumption the sound field impinges on the surface at normal incidence. This choice proved fruitful for every application. An impedance prediction model was used to design variable-depth liner configurations, and a graphical design code (ILIAD) was developed to aid in this process. The ability to build increasingly complex liner configurations via additive manufacturing was key, such that multiple designs could quickly be tested in a normal incidence impedance tube. The Two-Thickness Method was used to evaluate available bulk materials, such that bulk liners could also be considered for each application. These novel liner concepts provide sufficient noise reduction to warrant further investigations.

  18. 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.

  19. Production and grout liner for methane drainage in subterranean boreholes and method

    SciTech Connect

    Richards, W.L.; Henderson, R.L.; Aul, G.N.; Pauley, B.W.

    1987-08-18

    A process is described for recovering methane gas from subterranean coal seams using degas holes and sealing the degas holes after recovery of the methane gas in anticipation of mining of coal from the subterranean coal seam, the process comprising the steps of: drilling a generally horizontal degas hole into a subterranean coal seam using a drill bit and drill pipe; withdrawing the drill bit and drill pipe and thereafter replacing of the drill bit with a casing shoe; inserting the casing shoe and drill pipe into the degas hole; inserting the perforated liner into the borehole through the drill pipe; and, removing the drill pipe and casing shoe while holding the perforated liner within the degas hole, the casing shoe passing on the outside of the perforated liner as it is removed; collecting methane gas from the perforated liner, the methane gas entering the perforated liner through the perforations therein; thereafter pumping grout down the center of the perforated liner to the end of the degas hole; filling the end of the degas hole with grout until the end of the liner is filled with grout; increasing the pressure of the grout within the liner to force grout through the perforations in the liner to fill the degas hole along the length thereof; continuing to pump grout down the center of the perforated liner until the entire degas hole is filled with grout; and allowing the grout to set, thereby sealing the degas hole.

  20. 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.

  1. Energy conserving process for calcining clay

    SciTech Connect

    Baird, D.P.

    1990-08-14

    This patent describes an energy conversing process for calcining a clay. It comprises feeding a dry pulverized clay powder as feed material to a calciner to be calcined therein; passing the clay powder to be calcined through the calciner in direct heat exchange contact with a hot calcining gas passing therethrough whereby the clay powder is sufficiently heated to calcine substantially all the clay powder passing through the calciner and the hot calcining has is somewhat cooled; removing the calcined clay powder from the calciner and discharging the calcining from the calciner; subjecting the calciner discharge gas to electrostatic precipitation to clean the calciner discharge gas prior to venting the calciner discharge gas to the atmosphere whereby at least a substantial portion of calcined clay powder entrained in the calciner discharge gas is removed therefrom; collecting the hot calcined clay powder separated from the gas during electrostatic precipitation and mixing the collected hot calcined clay powder with the clay feed material being supplied to the calciner without substantially cooling the collected hot calcined clay powder prior to mixing with the feed material; and passing the calciner discharge has in heat exchange relationship with at least a portion of a cooling fluid prior to subjecting the calciner discharge gas to electrostatic precipitation.

  2. Contact micromechanics in granular media with clay

    SciTech Connect

    Ita, Stacey Leigh

    1994-08-01

    Many granular materials, including sedimentary rocks and soils, contain clay particles in the pores, grain contacts, or matrix. The amount and location of the clays and fluids can influence the mechanical and hydraulic properties of the granular material. This research investigated the mechanical effects of clay at grain-to-grain contacts in the presence of different fluids. Laboratory seismic wave propagation tests were conducted at ultrasonic frequencies using spherical glass beads coated with Montmorillonite clay (SWy-1) onto which different fluids were adsorbed. For all bead samples, seismic velocity increased and attenuation decreased as the contact stiffnesses increased with increasing stress demonstrating that grain contacts control seismic transmission in poorly consolidated and unconsolidated granular material. Coating the beads with clay added stiffness and introduced viscosity to the mechanical contact properties that increased the velocity and attenuation of the propagating seismic wave. Clay-fluid interactions were studied by allowing the clay coating to absorb water, ethyl alcohol, and hexadecane. Increasing water amounts initially increased seismic attenuation due to clay swelling at the contacts. Attenuation decreased for higher water amounts where the clay exceeded the plastic limit and was forced from the contact areas into the surrounding open pore space during sample consolidation. This work investigates how clay located at grain contacts affects the micromechanical, particularly seismic, behavior of granular materials. The need for this work is shown by a review of the effects of clays on seismic wave propagation, laboratory measurements of attenuation in granular media, and proposed mechanisms for attenuation in granular media.

  3. A mechanism of basal spacing reduction in sodium smectitic clay materials in contact with DNAPL wastes.

    PubMed

    Ayral-Cinar, Derya; Otero-Diaz, Margarita; Demond, Avery H

    2016-09-01

    There has been concern regarding the possible attack of clays in aquitards, slurry walls and landfill liners by dense nonaqueous phase liquid (DNAPL) wastes, resulting in cracking. Despite the fact that a reduction in basal spacing in sodium smectitic clay materials has been linked to cracking, no plausible mechanism by which this reduction occurs in contact with waste DNAPLs has been formulated. To elucidate a mechanism, screening studies were conducted that showed that the combination of an anionic surfactant (AOT), a nonionic surfactant (TritonX-100) and a chlorinated solvent, tetrachloroethylene (PCE), could replicate the basal spacing reduction and cracking behavior of water-saturated bentonite caused by two waste DNAPLs obtained from the field. FTIR measurements of this system showed a displacement of the HOH bending band of water symptomatic of desiccation. Sorption measurements showed that the uptake of AOT by bentonite increased eight fold in the presence of TritonX-100 and PCE. The evidence presented here supports a mechanism of syneresis, involving the extraction of water from the interlayer space of the clay through the synergistic sorption of a nonionic and anionic surfactant mixture. It is speculated that the solvation of water in reverse micellar aggregates is the process driving the syneresis.

  4. 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%).

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. Skin friction on a flat perforated acoustic liner

    NASA Technical Reports Server (NTRS)

    Boldman, D. R.; Brinich, P. F.

    1976-01-01

    The report concerns the measurement of friction coefficients of a typical perforated acoustic liner installed in the side of a wind tunnel. The results are compared with measured friction coefficients of a smooth hard wall for the same mean flow velocities in a wind tunnel. At a velocity of 61 m/sec, an increase in the local skin coefficient of only a few percent was observed, but at the highest velocity of 213 m/sec an increase of about 20% was obtained. This velocity is a realistic velocity for turbo-machinery components utilizing such liners, so a loss in performance is to be expected. Some tests were also performed to see if changes in the mean boundary layer induced by imposed noise would result in friction increase, but only at low velocity levels was such an increase in friction noted.

  13. 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

  14. 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.

  15. New Powder Technologies for Molybdenum Alloy Gun Barrel Liners

    DTIC Science & Technology

    1985-06-01

    bored from swaged rods (refs 1,2). Such liners failed after only a few rounds; transverse and longitudinal cracks were observed. A helical twisted 0.50...used by Nuclear Metals, Inc., Concord, MA (refs 7,8). For the REP, a water-cooled tungsten -tipped cathode is used to strike an electric arc to the... tungsten -tipped cathode, which has been found to introduce tungsten contamination. Both versions of the process have essentially the same constraint on

  16. 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.

  17. 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.

  18. Friction and wear behaviour of self lubricating bearing liners

    NASA Astrophysics Data System (ADS)

    Gay, Russell

    The thesis describes a numerical model for evaluating the variation of friction and wear of a self lubricating bearing liner over its useful wear life. Self-lubricating bearings have been in widespread use since the mid-1950s, particularly in the aerospace industry where they have the advantage of being low maintenance components. They are commonly used in relatively low speed, reciprocating applications such as control surface actuators, and usually consist of a spherical bearing with the inner and outer elements separated by a composite textile resin-bonded liner. A finite element model has been developed to predict the local stiffness of a particular liner at different states of wear. Results obtained using the model were used to predict the overall friction coefficient as it evolves due to wear, which is a novel approach. Experimental testing was performed on a bespoke flat-on-flat wear test rig with a reciprocating motion to validate the results of the friction model.. These tests were carried out on a commercially-available bearing liner, predominantly at a high contact pressure and an average sliding speed of 0.2 ms-1. Good agreement between predicted and experimentally measured wear was obtained when appropriate coefficients of friction were used in the friction model, and when the reciprocating sliding distance was above a critical value. A numerical wear model was also developed to predict the trend of backlash development in real bearing geometries using a novel approach. Results from the wear model were validated against full-scale bearing tests carried out elsewhere by the sponsoring company. Good agreement was obtained between the model predictions and the experimental results for the first 80% of the bearing wear life, and explanations for the discrepancy during the last 20% of the wear life have been proposed..

  19. THE COMPATIBILITY OF DENTURE CLEANSERS AND RESILIENT LINERS

    PubMed Central

    Oliveira, Luciana Valadares; Mesquita, Marcelo Ferraz; Henriques, Guilherme Elias Pessanha; Consani, Rafael Leonardo Xediek; Fragoso, Wagner Sotero

    2006-01-01

    Purpose: Difficulty in cleaning resilient denture liners remains a material disadvantage. The purpose of the present study was to evaluate the effect of denture cleansers on hardness of resilient liner materials. Materials and Methods: Three resilient liners, Luci Sof® (Dentsply), Molloplast-B® (Dentax), and Sofreliner® (Tokuyama), and two denture cleansers, Efferdent® (Warner-Lamber), and 0.5% alkaline hypochlorite preparation were used. Twenty specimens of each material were prepared, measuring 25X15X3mm. Two denture cleansing approaches were used: 1) alkaline hypochlorite, for 20 minutes; 2) alkaline peroxide, for 30 minutes. This procedure was repeated 8 times a day, during 90 days. The specimens were evaluated before and after 360 and 720 cycles, to simulate 1 and 2 years of clinical cleaning procedures, respectively. The Shore A hardness was evaluated in a durometer (Teclock GS-709A), with a penetrating load of 10N for 1 second. Any macroscopic changes, such as loss of color or alteration in surface texture were recorded by one observer. All numeric data were subject to ANOVA with repeated measures followed by Tukey's test (α= 0.05). Results: All materials were significantly different, independently to time and treatment. Initially, Luci Sof® and Sofreliner® immersed in either hypochlorite or peroxide increased the hardness mean values significantly. These hardness mean values decreased significantly after 720 cycles. Molloplast-B® showed no significant difference after the treatments, in any time. Conclusions: Denture cleansers had no effect on hardness of the resilient denture liners evaluated after 2 years of in vivo simulated conditions of hygiene. Sofreliner® was the smoothest material before and after all treatments. PMID:19089278

  20. 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.

  1. Hyperspectral analysis of clay minerals

    NASA Astrophysics Data System (ADS)

    Janaki Rama Suresh, G.; Sreenivas, K.; Sivasamy, R.

    2014-11-01

    A study was carried out by collecting soil samples from parts of Gwalior and Shivpuri district, Madhya Pradesh in order to assess the dominant clay mineral of these soils using hyperspectral data, as 0.4 to 2.5 μm spectral range provides abundant and unique information about many important earth-surface minerals. Understanding the spectral response along with the soil chemical properties can provide important clues for retrieval of mineralogical soil properties. The soil samples were collected based on stratified random sampling approach and dominant clay minerals were identified through XRD analysis. The absorption feature parameters like depth, width, area and asymmetry of the absorption peaks were derived from spectral profile of soil samples through DISPEC tool. The derived absorption feature parameters were used as inputs for modelling the dominant soil clay mineral present in the unknown samples using Random forest approach which resulted in kappa accuracy of 0.795. Besides, an attempt was made to classify the Hyperion data using Spectral Angle Mapper (SAM) algorithm with an overall accuracy of 68.43 %. Results showed that kaolinite was the dominant mineral present in the soils followed by montmorillonite in the study area.

  2. 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.

  3. 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.

  4. Simulation studies of plasma target compression by argon liners

    NASA Astrophysics Data System (ADS)

    Zhang, Lina; Kim, Hyoungkeun; Samulyak, Roman; Roman Samulyak Team

    2013-10-01

    Simulation studies of plasma liners, formed by the merger of argon plasma jets, and the compression of plasma targets in the concept of the plasma jet driven magnetoinertial fusion have been performed using FronTier code. FromTier is a hybrid Lagrangian-Eulerian code that uses explicit tracking of material interfaces, thus enabling accurate resolution of hydro instabilities, and average ionization EOS models for high-Z materials. The jets merger process is accomplished through a cascade of oblique shock waves leading to the non-uniformity of imploding plasma liner and causing the Reyleigh-Taylor instability of target during compression. The stagnation pressure, deconfinement time, Rayleigh-Taylor instabilities of the target surface, and the production of fusion neutrons were analyzed for 2D simulations that included 8, 16, and 32 jets, 3D simulation with 90 jets, and compared with the corresponding cylindrically (2D) and spherically (3D) symmetric simulations. The liner non-uniformity induces instabilities in the plasma targets that result in the reduction of stagnation pressure and fusion energy. For example, 8 time reduction of the stagnation pressure and 31 time reduction of the fusion energy was observed when the 2D simulation involving 16 jets was compared to 1D simulation.

  5. 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.

  6. 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.

  7. 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.

  8. Modernity and putty-clay

    NASA Astrophysics Data System (ADS)

    Ganesh, Trichur Kailas

    This dissertation addresses issues arising out of the problems of capital accumulation, productivity growth and 'putty-clay' technology. The concept of economic modernity occupies a central place in the subject-matter studied here in that it expresses both the incessant drive for newness that characterizes economic reality and the persistence of dated techniques that successfully resist replacement. This study examines the way in which an expansive development-theoretic 'putty-clay' framework may be employed to explain the historical processes behind both the avalanche of newness (innovations) and the conservatism of technology in the U.S. economy. The guiding link is the fixity of investments in physical capital equipment over time and space. The dilemma of fixed capital is studied in the context of the constant entrepreneurial search for flexibility and liquidity. The thesis advanced is that a development (Entwicklung)-theoretic 'putty-clay' conceptualization of the economic system adequately addresses the recurring problems of fixity, flexibility, and liquidity, and thereby permits important insights into the enigma surrounding the persistent productivity growth slowdown and 'stagflation' of the late sixties and seventies and the related phenomena of physical 'capital obsolescence' and the financial or 'speculative explosions' of our times. The notion of 'putty-clay' used here is an innovative one in that it departs from the growth-theoretic literature to re-appear as a Schumpeterian theory of modernity modified by a Veblenite view of an economic system directed by the exigencies of the 'machine-process'. The empirical aptitude of a macroeconomic 'putty-clay' model to explain capital obsolescence mediated by the energy 'crises' (supply shocks) of the seventies and eighties is examined in a separate chapter with results that differ markedly from the standard (Berndt and Wood) conclusions for the U.S. economy. The final chapter in the dissertation reverts to the

  9. Comparison of Calculated and Experimental Total-Pressure Loss and Airflow Distribution in Tubular Turbojet Combustors with Tapered Liners

    NASA Technical Reports Server (NTRS)

    Grobman, Jack S.

    1959-01-01

    Incompressible-flow calculations were performed to determine the effects of combustor geometric and operating variables on pressure loss and airflow distribution in a tubular combustor with a tapered liner. The calculations include the effects of momentum transfer between annulus and liner gas streams, annulus wall friction, heat release, and discharge coefficients of liner air-entry holes. Generalized curves are presented which show the effects of liner-wall inclination, liner open hole area, and temperature rise across the combustor on pressure loss and airflow distribution for a representative parabolic liner hole distribution. A comparison of the experimental data from 12 tapered liners with the theoretical calculations indicates that reasonable design estimates can be made from the generalized curves. The calculated pressure losses of the tapered liners are compared with those previously reported for tubular liners.

  10. 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.

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

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel L.; 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.

  12. Fusion Reactor and Break-Even Experiment Based on Stabilized Liner Compression of Plasma

    NASA Astrophysics Data System (ADS)

    Turchi, Peter; Frese, Sherry; Frese, Michael

    2016-10-01

    An optimum regime, known as magnetized-target or magneto-inertial fusion (MTF/MIF), requires magnetic fields at megagauss levels, which are attainable by use of dynamic conductors called liners. The stabilized liner compressor (SLC) provides the basis for controlled implosion and re-capture of the liner for reversible energy exchange between liner kinetic energy and the internal energy of a magnetized-plasma target. This exchange requires rotational stabilization of Rayleigh-Taylor modes on the inner surface of the liner and pneumatically driven free-pistons that eliminate such modes at the outer surface. We discuss the implications of the SLC approach for the power reactor, a breakeven experiment, and intermediate experiments to develop the plasma target. Features include the importance of pneumatic drive and the liner-blanket for economic feasibility of MTF/MIF. Supported by ARPA-E ALPHA Program.

  13. On the structure of plasma liners for plasma jet induced magnetoinertial fusion

    SciTech Connect

    Kim, Hyoungkeun; Zhang, Lina; Samulyak, Roman; Parks, Paul

    2013-02-15

    The internal structure and self-collapse properties of plasma liners, formed by the merger of argon plasma jets, have been studied via 3-dimensional numerical simulations using the FronTier code. We have shown that the jets merger process is accomplished through a cascade of oblique shock waves that heat the liner and reduce its Mach number. Oblique shock waves and the adiabatic compression heating have led to the 10 times reduction of the self-collapse pressure of a 3-dimensional argon liner compared to a spherically symmetric liner with the same pressure and density profiles at the merging radius. We have also observed a factor of 10 variations of pressure and density in the leading edge of the liner along spherical surfaces close to the interaction with potential plasma targets. Such a non-uniformity of imploding plasma liners presents problems for the stability of targets during compression.

  14. 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.

  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. 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.

  17. 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

  18. Effect of liner and porcelain application on zirconia surface structure and composition

    PubMed Central

    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

  19. Study of Liner Collapse, Jet Formation and Characteristics from Implosive Shaped Charge Systems

    DTIC Science & Technology

    1977-11-01

    later. Figure 14 shows a plot of the velocity versus time for ten different tracer particles placed on the inside surface of the hemispherical liner...while figures 15 through 17 show plots of velocities versus time of four particles placed across the liner thickness at three different locations, one on...experimental data. Figure 18 shows a plot of the average velocity components of the metallic liner as a function of time, while Figure 19 shows the different

  20. 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.

  1. A Method for Optimizing Non-Axisymmetric Liners for Multimodal Sound Sources

    NASA Technical Reports Server (NTRS)

    Watson, W. R.; Jones, M. G.; Parrott, T. L.; Sobieski, J.

    2002-01-01

    Central processor unit times and memory requirements for a commonly used solver are compared to that of a state-of-the-art, parallel, sparse solver. The sparse solver is then used in conjunction with three constrained optimization methodologies to assess the relative merits of non-axisymmetric versus axisymmetric liner concepts for improving liner acoustic suppression. This assessment is performed with a multimodal noise source (with equal mode amplitudes and phases) in a finite-length rectangular duct without flow. The sparse solver is found to reduce memory requirements by a factor of five and central processing time by a factor of eleven when compared with the commonly used solver. Results show that the optimum impedance of the uniform liner is dominated by the least attenuated mode, whose attenuation is maximized by the Cremer optimum impedance. An optimized, four-segmented liner with impedance segments in a checkerboard arrangement is found to be inferior to an optimized spanwise segmented liner. This optimized spanwise segmented liner is shown to attenuate substantially more sound than the optimized uniform liner and tends to be more effective at the higher frequencies. The most important result of this study is the discovery that when optimized, a spanwise segmented liner with two segments gives attenuations equal to or substantially greater than an optimized axially segmented liner with the same number of segments.

  2. 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

  3. Development of reduced drag concepts for acoustic liners using experimental methods

    NASA Astrophysics Data System (ADS)

    Jasinski, Christopher

    2016-11-01

    Commercial aircraft have used acoustic liners to reduce engine noise for many years, although their drag production has been largely unstudied. The next generation of aircraft may benefit from additional surface area covered by acoustic liner, thus understanding their drag production mechanism is crucial for future designs. An accurate direct aerodynamic drag measurement technique has been developed using a force balance with linear air bearings. Using 3D-printed and conventional liners, low-drag designs are being developed. This paper will investigate the underlying fluid mechanics governing the drag production in acoustic liners and describe new attempts to reduce aerodynamic drag.

  4. 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.

  5. 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.

  6. Ceramic coating effect on liner metal temperatures of film-cooled annular combustor

    NASA Technical Reports Server (NTRS)

    Claus, R. W.; Wear, J. D.; Liebert, C. H.

    1979-01-01

    An experimental and analytical investigation was conducted to determine the effect of a ceramic coating on the average metal temperatures of full annular, film cooled combustion chamber liner. The investigation was conducted at pressures from 0.50 to 0.062. At all test conditions, experimental results indicate that application of a ceramic coating will result in significantly lower wall temperatures. In a simplified heat transfer analysis, agreement between experimental and calculated liner temperatures was achieved. Simulated spalling of a small portion of the ceramic coating resulted in only small increases in liner temperature because of the thermal conduction of heat from the hotter, uncoated liner metal.

  7. Comparison of shaped charge liner cone and recovered jet fragment microstructures to elucidate dynamic recrystallization phenomena

    NASA Astrophysics Data System (ADS)

    Murr, L. E.; Niou, C.-S.; Sanchez, J. C.; Zernow, L.

    1995-01-01

    In order to prove the occurrence of dynamic recrystallization (DRX) following detonation of copper and tantalum shape charge liner cones, reductions in the starting grain size of the liner cones and recovered slug and jet fragments were compared. Forged copper cone liner having a grain size of 15 micrometer was also produced and the end point microstructures were compared with previous results and observations for a starting cone grain size of 35 micrometer. Microstructures in shaped charge starting liner cones and recovered jet fragments were observed by both optical metallography and transmission electron microscopy.

  8. The use of volcanic soil as mineral landfill liner--I. Physicochemical characterization and comparison with zeolites.

    PubMed

    Navia, Rodrigo; Hafner, Georg; Raber, Georg; Lorber, Karl E; Schöffmann, Elke; Vortisch, Walter

    2005-06-01

    The main physicochemical characteristics of the volcanic soil of Southern Chile, with allophane as the main pedogenic mineral phase were analysed and compared with common zeolites (clinoptilolite) of the European market. The ultimate goal of this study was to test volcanic soil for the use as mineral landfill liner. The main results indicated that the clay and silt fractions together of the volcanic soil were between 38 and 54%. The buffering capacity of the volcanic soil was higher compared with the studied zeolites, whereas the cationic exchange capacity of the volcanic soil (between 5.2 and 6.5 cmol + kg(-1)) is of the same order of magnitude of the studied zeolites (between 9.7 and 11.4 cmol + kg(-1)). Moreover, the anionic exchange capacity of the volcanic soil was higher compared to the zeolites analysed. The hydraulic conductivity of the volcanic soil, measured in the laboratory at maximum proctor density, ranges between 5.16 x 10(-9) and 6.48 x 10(-9) m s(-1), a range that is comparable to the value of 4.51 x 10(-9) m s(-1) of the studied zeolite. The Proctor densities of the volcanic soil are in a lower range (between 1.11 and 1.15 g ml(-1)) compared with zeolites (between 1.19 and 1.34 g ml(-1)). The volcanic soil physicochemical characteristics are comparable to all the requirements established in the Austrian landfill directive (DVO, 2000). Therefore, the use as mineral landfill basal sealing of the analysed volcanic soil appears reasonable, having a pollutant adsorption capacity comparable to zeolites. It is of special interest for Southern Chile, because there are no alternative mineral raw materials for basal liners of landfills.

  9. Mars, clays and the origins of life

    NASA Technical Reports Server (NTRS)

    Hartman, Hyman

    1989-01-01

    To detect life in the Martian soil, tests were designed to look for respiration and photosynthesis. Both tests (labeled release, LR, and pyrolytic release, PR) for life in the Martian soils were positive. However, when the measurement for organic molecules in the soil of Mars was made, none were found. The interpretation given is that the inorganic constituents of the soil of Mars were responsible for these observations. The inorganic analysis of the soil was best fitted by a mixture of minerals: 60 to 80 percent clay, iron oxide, quartz, and soluble salts such as halite (NaCl). The minerals most successful in simulating the PR and LR experiments are iron-rich clays. There is a theory that considers clays as the first organisms capable of replication, mutation, and catalysis, and hence of evolving. Clays are formed when liquid water causes the weathering of rocks. The distribution of ions such as aluminum, magnesium, and iron play the role of bases in the DNA. The information was stored in the distribution of ions in the octahedral and tetrahedral molecules, but that they could, like RNA and DNA, replicate. When the clays replicated, each sheet of clay would be a template for a new sheet. The ion substitutions in one clay sheet would give rise to a complementary or similar pattern on the clay synthesized on its surface. It was theorized that it was on the surface of replicating iron-rich clays that carbon dioxide would be fixed in the light into organic acids such as formic or oxalic acid. If Mars had liquid water during a warm period in its past, clay formation would have been abundant. These clays would have replicated and evolved until the liquid water was removed due to cooling of Mars. It is entirely possible that the Viking mission detected life on Mars, but it was clay life that awaits the return of water to continue its evolution into life based on organic molecules.

  10. Selective Clay Placement Within a Silicate-Clay Epoxy Blend Nanocomposite

    NASA Technical Reports Server (NTRS)

    Miller, Sandi G (Inventor)

    2013-01-01

    A clay-epoxy nanocomposite may be prepared by dispersing a layered clay in an alkoxy epoxy, such as a polypropylene oxide based epoxide before combining the mixture with an aromatic epoxy to improve the nanocomposite's thermal and mechanical properties.

  11. Iodide uptake by negatively charged clay interlayers?

    PubMed

    Miller, Andrew; Kruichak, Jessica; Mills, Melissa; Wang, Yifeng

    2015-09-01

    Understanding iodide interactions with clay minerals is critical to quantifying risk associated with nuclear waste disposal. Current thought assumes that iodide does not interact directly with clay minerals due to electrical repulsion between the iodide and the negatively charged clay layers. However, a growing body of work indicates a weak interaction between iodide and clays. The goal of this contribution is to report a conceptual model for iodide interaction with clays by considering clay mineral structures and emergent behaviors of chemical species in confined spaces. To approach the problem, a suite of clay minerals was used with varying degrees of isomorphic substitution, chemical composition, and mineral structure. Iodide uptake experiments were completed with each of these minerals in a range of swamping electrolyte identities (NaCl, NaBr, KCl) and concentrations. Iodide uptake behaviors form distinct trends with cation exchange capacity and mineral structure. These trends change substantially with electrolyte composition and concentration, but do not appear to be affected by solution pH. The experimental results suggest that iodide may directly interact with clays by forming ion-pairs (e.g., NaI(aq)) which may concentrate within the interlayer space as well as the thin areas surrounding the clay particle where water behavior is more structured relative to bulk water. Ion pairing and iodide concentration in these zones is probably driven by the reduced dielectric constant of water in confined space and by the relatively high polarizability of the iodide species.

  12. 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

  13. In situ clay formation : evaluation of a proposed new technology for stable containment barriers.

    SciTech Connect

    Nagy, Kathryn L.; DiGiovanni, Anthony Albert; Fredrich, Joanne T.

    2004-03-01

    Containment of chemical wastes in near-surface and repository environments is accomplished by designing engineered barriers to fluid flow. Containment barrier technologies such as clay liners, soil/bentonite slurry walls, soil/plastic walls, artificially grouted sediments and soils, and colloidal gelling materials are intended to stop fluid transport and prevent plume migration. However, despite their effectiveness in the short-term, all of these barriers exhibit geochemical or geomechanical instability over the long-term resulting in degradation of the barrier and its ability to contain waste. No technologically practical or economically affordable technologies or methods exist at present for accomplishing total remediation, contaminant removal, or destruction-degradation in situ. A new type of containment barrier with a potentially broad range of environmental stability and longevity could result in significant cost-savings. This report documents a research program designed to establish the viability of a proposed new type of containment barrier derived from in situ precipitation of clays in the pore space of contaminated soils or sediments. The concept builds upon technologies that exist for colloidal or gel stabilization. Clays have the advantages of being geologically compatible with the near-surface environment and naturally sorptive for a range of contaminants, and further, the precipitation of clays could result in reduced permeability and hydraulic conductivity, and increased mechanical stability through cementation of soil particles. While limited success was achieved under certain controlled laboratory conditions, the results did not warrant continuation to the field stage for multiple reasons, and the research program was thus concluded with Phase 2.

  14. 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.

  15. 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

  16. The polyhedral nature of LINERs: an XMM-Newton view of LINERs in radio galaxies

    NASA Astrophysics Data System (ADS)

    Gliozzi, M.; Foschini, L.; Sambruna, R. M.; Tavecchio, F.

    2008-02-01

    Aims:We investigate the origin of X-rays and the nature of accretion flow in 4 low-ionization nuclear emission-line regions (LINERs) hosted by radio galaxies, namely NGC 1692, PKS 0625-35, 3C 88, 3C 444, recently observed with XMM-Newton. Methods: We combine the results from the time-averaged spectral analysis with model-independent information from X-ray temporal and spectral variability analyses, and with additional broadband information (specifically from the UV band, covered by the Optical Monitor aboard XMM-Newton, and from archival radio data). Results: The values of the Eddington ratios L_bol/L_Edd of our sample span 2 orders of magnitude ranging between ~1×10-5 and 1×10-3. The 4 AGN are adequately fitted by the same continuum model that comprises at least one thermal component (kT ~ 0.65-1.45 keV) and a partially absorbed power law, whose relative contribution and photon index vary substantially from source to source. NGC 1692 and PKS 0625-35 have fairly steep power-law components (Γ ~ 2.5-2.9), perhaps indicative of synchrotron emission from the base of a jet. Conversely, the flat photon index derived for 3C 88 (Γ ~ 1.1) may be indicative of a heavily absorbed object. Finally, the time-averaged spectral properties of 3C 444 (Γ ~ 1.9 and an apparent line-like excess around 6.7 keV) are more in line with Seyfert-like objects. The temporal analysis reveals that PKS 0625-35 and 3C 88 are significantly variable in the soft (0.2-1 keV) energy band. PKS 0625-35 also shows suggestive evidence of spectral variability on timescales of months, with a spectral softening associated with the source brightening. NGC 1692 is only marginally variable in the soft band, whereas 3C 444 does not show significant variability on short timescales. The main findings from the broadband analysis can be summarized as follows: 1) 3C 444, PKS 0625-35, and NGC 1692 have αOX values consistent with the αOX - lUV correlation found by Steffen et al. (2006, AJ, 131, 2826) for Seyfert

  17. 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.

  18. Freeze-agglomeration: An alternative mechanism for clay film formation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oriented clay coatings (argillans, clay cutans, clay films, lamellae) are often interpreted to be caused by illuviation (pervection, lessivage) of fine clay particles. In montane meadow soils (Typic Humaquepts) of the northern Sierra Nevada Range, prominent clay cutans occur on ped faces of a paleos...

  19. 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.

  20. 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.

  1. Intercalated layered clay composites and their applications

    NASA Astrophysics Data System (ADS)

    Phukan, Anjali

    Supported inorganic reagents are rapidly emerging as new and environmentally acceptable reagents and catalysts. The smectite group of layered clay minerals, such as, Montmorillonite, provides promising character for adsorption, catalytic activity, supports etc. for their large surface area, swelling behavior and ion exchange properties. Aromatic compounds intercalated in layered clays are useful in optical molecular devices. Clay is a unique material for adsorption of heavy metals and various toxic substances. Clay surfaces are known to be catalytically active due to their surface acidity. Acid activated clays possess much improved surface areas and acidities and have higher pore volumes so that can absorb large molecules in the pores. The exchangeable cations in clay minerals play a key role in controlling surface acidity and catalytic activity. Recently, optically active metal-complex-Montmorillonite composites are reported to be active in antiracemization purposes. In view of the above, a research work, relating to the preparation of different modified clay composites and their catalytic applications were carried out. The different aspects and results of the present work have been reported in four major chapters. Chapter I: This is an introductory chapter, which contains a review of the literature regarding clay-based materials. Clay minerals are phyllosilicates with layer structure. Montmorillonite, a member of smectite group of clay, is 2:1 phyllosilicate, where a layer is composed of an octahedral sheet sandwiched by two tetrahedral sheets. Such clay shows cation exchange capacity (CEC) and is expressed in milli-equivalents per 100 gm of dry clay. Clays can be modified by interaction with metal ion, metal complexes, metal cluster and organic cations for various applications. Clays are also modified by treating with acid followed by impregnation with metal salts or ions. Montmorillonite can intercalate suitable metal complexes in excess of CEC to form double

  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. 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.

  4. 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.

  5. 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.

  6. Testing of elastomeric liners used in limb prosthetics: classification of 15 products by mechanical performance.

    PubMed

    Sanders, Joan E; Nicholson, Brian S; Zachariah, Santosh G; Cassisi, Damon V; Karchin, Ari; Fergason, John R

    2004-03-01

    The mechanical properties of 15 elastomeric liner products used in limb prosthetics were evaluated under compressive, frictional, shear, and tensile loading conditions. All testing was conducted at load levels comparable to interface stress measurements reported on transtibial amputee subjects. For each test configuration, materials were classified into four groups based on the shapes of their response curves. For the 15 liners tested, there were 10 unique classification sets, indicating a wide range of unique materials. In general, silicone gel liners classified within the same groups thus were quite similar to each other. They were of lower compressive, shear, and tensile stiffness than the silicone elastomer products, consistent with their lightly cross-linked, high-fluid content structures. Silicone elastomer products better spanned the response groups than the gel liners, demonstrating a wide range of compressive, shear, and tensile stiffness values. Against a skin-like material, a urethane liner had the highest coefficient of friction of any liner tested, although coefficients of friction values for most of the materials were higher than interface shear:pressure ratios measured on amputee subjects using Pelite liners. The elastomeric liner material property data and response groupings provided here can potentially be useful to prosthetic fitting by providing quantitative information on similarities and differences among products.

  7. 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...

  8. 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.

  9. 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.

  10. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations...) You must test each drilling liner (and liner-lap) to a pressure at least equal to the anticipated... drilling or other down-hole operations until you obtain a satisfactory pressure test. If the...

  11. 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.

  12. 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.

  13. Tendency of spherically imploding plasma liners formed by merging plasma jets to evolve toward spherical symmetry

    SciTech Connect

    Cassibry, J. T.; Stanic, M.; Hsu, S. C.; Witherspoon, F. D.; Abarzhi, S. I.

    2012-05-15

    We have performed three-dimensional (3D) simulations using smoothed particle hydrodynamics (SPH) in order to study the effects of discrete plasma jets on the processes of plasma liner formation, implosion on vacuum, and expansion. It was found that the pressure histories of the inner portion of the liner from 3D SPH simulations with a uniform liner and with 30 discrete plasma jets were qualitatively and quantitatively similar from peak compression through the complete stagnation of the liner. The 3D simulations with a uniform liner were first benchmarked against results from one-dimensional radiation-hydrodynamic simulations [T. J. Awe et al., Phys. Plasmas 18, 072705 (2011)]. Two-dimensional plots of the pressure field show that the discrete jet SPH case evolves towards a profile that is almost indistinguishable from the SPH case with a uniform liner, thus indicating that non-uniformities due to discrete jets are smeared out by late stages of the implosion. The processes of plasma liner formation and implosion on vacuum were shown to be robust against Rayleigh-Taylor instability growth. Finally, interparticle mixing for a liner imploding on vacuum was investigated. The mixing rate was found to be very small until after the peak compression for the 30 jet simulations.

  14. 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.

  15. 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.

  16. A comparison between the X-ray properties of LINERs/LLAGNs and normal galaxies

    NASA Astrophysics Data System (ADS)

    Awaki, H.

    I reviewed recent X-ray observations of LINERs and low luminosity AGNs (LLAGNs) with the Japanese X-ray satellite ASCA. The main purpose of the ASCA observations was to reveal the X-ray properties of these galaxies, especially nuclear activity. ASCA observed 15 LLAGNs and found nuclear X-ray emission for 13 LLAGNs except NGC 1672 and NGC 4501. On the other hand, compact hard X-ray emission probably associated with nuclear activity was found in seven LINERs, and six LINERs among seven have a broad Hα line. This result suggests that the excitation mechanism of these LINERs is photoionization. Soft X-ray emission from LINERs was found, and the emission can be associated with the starbust phenomenon in LINERs. I characterized the variability time scale using the Fourier timing analysis and deduced the lower limit of central black hole mass. The black hole masses are greater than 107 solar mass, which are consistent with those of high luminosity AGNs. However, the X-ray luminosity of LLAGNs and LINERs are only 11000 of that of high-luminosity AGNs. This indicates that LLAGNs and LINERs may turn into AGNs if fuel is supplied to the central black hole.

  17. Status of Duct Liner Technology for Application to Aircraft Engine Nacelles

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

    Grazing flows and high acoustic intensities impose unusual design requirements on acoustic liner treatments used in aircraft engine nacelles. Increased sound absorption efficiency (requiring increased accuracy of liner impedance specification) is particularly critical in the face of ever decreasing nacelle wall area available for liner treatments in modern, high-bypass ratio engines. This paper reviews the strategy developed at Langley Research Center for achieving a robust measurement technology that is crucial for validating impedance models for aircraft liners. Specifically, the paper describes the current status of computational and data acquisition technologies for reducing impedance in a flow duct. Comparisons of reduced impedances for a "validation liner" using 1980's and 2000's measurement technology are consistent, but show significant deviations (up to 0.5 c exclusive of liner anti-resonance region) from a first principles impedance prediction model as grazing flow centerline Mach numbers increase up to 0.5. The deviations, in part, are believed related to uncertainty in the choice of grazing flow parameters (e.g. cross-section averaged, core-flow averaged, or centerline Mach number?). Also, there may be an issue with incorporating the impedance discontinuities corresponding to the hard wall to liner interface (i.e. leading and trailing edge of test liner) within the discretized finite element model.

  18. 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...

  19. 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.

  20. [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.

  1. Sectioning Clay Models Makes Anatomy & Development Tangible

    ERIC Educational Resources Information Center

    Howell, Carina Endres; Howell, James Endres

    2010-01-01

    Clay models have proved to be useful teaching aids for many topics in biology that depend on three-dimensional reasoning. Students studying embryonic development struggle to mentally reconstruct the three-dimensional structure of embryos and larvae by observing prepared slides of cross-sectional slices. Students who build clay models of embryos…

  2. Clay smear: Review of mechanisms and applications

    NASA Astrophysics Data System (ADS)

    Vrolijk, Peter J.; Urai, Janos L.; Kettermann, Michael

    2016-05-01

    Clay smear is a collection of fault processes and resulting fault structures that form when normal faults deform layered sedimentary sections. These elusive structures have attracted deep interest from researchers interested in subsurface fluid flow, particularly in the oil and gas industry. In the four decades since the association between clay-smear structures and oil and gas accumulations was introduced, there has been extensive research into the fault processes that create clay smear and the resulting effects of that clay smear on fluid flow. We undertake a critical review of the literature associated with outcrop studies, laboratory and numerical modeling, and subsurface field studies of clay smear and propose a comprehensive summary that encompasses all of these elements. Important fault processes that contribute to clay smear are defined in the context of the ratio of rock strength and in situ effective stresses, the geometric evolution of fault systems, and the composition of the faulted section. We find that although there has been progress in all avenues pursued, progress has been uneven, and the processes that disrupt clay smears are mostly overlooked. We highlight those research areas that we think will yield the greatest benefit and suggest that taking these emerging results within a more process-based framework presented here will lead to a new generation of clay smear models.

  3. Surface geochemistry of the clay minerals

    PubMed Central

    Sposito, Garrison; Skipper, Neal T.; Sutton, Rebecca; Park, Sung-ho; Soper, Alan K.; Greathouse, Jeffery A.

    1999-01-01

    Clay minerals are layer type aluminosilicates that figure in terrestrial biogeochemical cycles, in the buffering capacity of the oceans, and in the containment of toxic waste materials. They are also used as lubricants in petroleum extraction and as industrial catalysts for the synthesis of many organic compounds. These applications derive fundamentally from the colloidal size and permanent structural charge of clay mineral particles, which endow them with significant surface reactivity. Unraveling the surface geochemistry of hydrated clay minerals is an abiding, if difficult, topic in earth sciences research. Recent experimental and computational studies that take advantage of new methodologies and basic insights derived from the study of concentrated ionic solutions have begun to clarify the structure of electrical double layers formed on hydrated clay mineral surfaces, particularly those in the interlayer region of swelling 2:1 layer type clay minerals. One emerging trend is that the coordination of interlayer cations with water molecules and clay mineral surface oxygens is governed largely by cation size and charge, similarly to a concentrated ionic solution, but the location of structural charge within a clay layer and the existence of hydrophobic patches on its surface provide important modulations. The larger the interlayer cation, the greater the influence of clay mineral structure and hydrophobicity on the configurations of adsorbed water molecules. This picture extends readily to hydrophobic molecules adsorbed within an interlayer region, with important implications for clay–hydrocarbon interactions and the design of catalysts for organic synthesis. PMID:10097044

  4. Uranium in clays of crystalline rocks

    SciTech Connect

    Simmons, G.; Caruso, L.

    1985-03-10

    Uraniferous clay aggregates in several granites have been examined in detail with a scanning electron microscope (SEM) equipped with a high resolution backscattered electron detector (BSE) and an energy dispersive x-ray system (EDS). The same polished sections used for the microscope observations were irradiated with thermal neutrons and the etched lexan detectors were then used to determine the location of uranium with a spatial resolution of a few microns. A set of 100 samples of the following granites were used for this study: Carnmenellis granite of southwestern England, Conway and Mount Osceola granites of central New Hampshire, Sherman granite of Wyoming and Colorado, Granite Mountains granite of Wyoming, several granites from central Maine, and the Graniteville granite of Missouri. These samples contain clay rich regions as large as a few millimeters that appear to consist entirely of clay when examined with the petrographic microscope. The clays are smectite, nontronite, or vermiculite. The fission track detectors show uranium to be present within the regions. Close examination with the BSE and EDS, however, shows in every instance that the host for the uranium is not clay but clay-sized grains of the following minerals: bastnesite group, hematite, siderite, secondary monazite, secondary thorite, and several different Y-bearing niobates. This finding may have severe implications for the long-term retention of uranium and transuranic elements adsorbed on clay. Perhaps the presence of clay is not significant for the long-term retention of radioisotopes. 22 refs., 7 figs.

  5. Using Clay Therapy To Change Negative Behaviors.

    ERIC Educational Resources Information Center

    Kahn, Victoria

    This manual describes a clay therapy program appropriate for use with students having a variety of exceptionalities and in an age range from 6 to 18 years. Organization and staffing are briefly discussed followed by a list of long range goals (affective, motoric, and aesthetic), suggestions for clay therapy implementation to achieve these goals,…

  6. Dehydration-induced luminescence in clay minerals

    NASA Technical Reports Server (NTRS)

    Coyne, L. M.; Lahav, N.; Lawless, J. G.

    1981-01-01

    Reports of triboluminescent phenomena in organic crystalline materials prompted a search for related processes in clay minerals. The reported extensive mechanical distortion produced on freezing and drying of montmorillonite was particularly interesting because of studies of condensation reactions in a wet/dry cycled reaction sequence. The discovery of an unusual luminescent process in several clay minerals is reported and its characteristics are described.

  7. The colloidal chemistry of ceramic clays

    NASA Technical Reports Server (NTRS)

    Phelps, G. W.

    1984-01-01

    The colloidal chemistry and mineralogy of two argil minerals were studied. Deposits of kaolin and of ceramic clays in the United States and England are discussed for the probable mechanism of formation. The structural modifications of the bed, original material associated with the clays and the proper use of flocculants are discussed.

  8. A finite element simulation of sound attenuation in a finite duct with a peripherally variable liner

    NASA Technical Reports Server (NTRS)

    Watson, W. R.

    1977-01-01

    Using multimodal analysis, a variational finite element method is presented for analyzing sound attenuation in a three-dimensional finite duct with a peripherally variable liner in the absence of flow. A rectangular element, with cubic shaped functions, is employed. Once a small portion of a peripheral liner is removed, the attenuation rate near the frequency where maximum attenuation occurs drops significantly. The positioning of the liner segments affects the attenuation characteristics of the liner. Effects of the duct termination are important in the low frequency ranges. The main effect of peripheral variation of the liner is a broadening of the attenuation characteristics in the midfrequency range. Because of matrix size limitations of the presently available computer program, the eigenvalue equations should be solved out of core in order to handle realistic sources.

  9. Effect of microseparation and third-body particles on dual-mobility crosslinked hip liner wear.

    PubMed

    Netter, Jonathan D; Hermida, Juan C; Chen, Peter C; Nevelos, James E; D'Lima, Darryl D

    2014-09-01

    Large heads have been recommended to reduce the risk of dislocation after total hip arthroplasty. One of the issues with larger heads is the risk of increased wear and damage in thin polyethylene liners. Dual-mobility liners have been proposed as an alternative to large heads. We tested the wear performance of highly crosslinked dual-mobility liners under adverse conditions simulating microseparation and third-body wear. No measurable increase in polyethylene wear rate was found in the presence of third-body particles. Microseparation induced a small increase in wear rate (2.9mm(3)/million cycles). A finite element model simulating microseparation in dual-mobility liners was validated using these experimental results. The results of our study indicate that highly crosslinked dual-mobility liners have high tolerance for third-body particles and microseparation.

  10. Field performance assessment of synthetic liners for uranium tailings ponds: a status report

    SciTech Connect

    Mitchell, D.H.; Spanner, G.E.

    1984-03-01

    The objective of this study is to provide a database to support US Nuclear Regulatory Commission (NRC) licensing of uranium tailings leachate isolation impoundments. This objective is being accomplished by determining the effectiveness of design, installation, and quality assurance practices associated with uranium mill tailings impoundments with flexible membrane liners. The program includes testing of chemical resistance and physical performance of liners, leak detection systems, and seam inspection techniques. This report presents the status of the program through September 1983. The report addresses impoundment design, installation, and inspection techniques used by the uranium milling industry. To determine the relative successes of these techniques, information has been collected from consultants, mill operators, and the synthetic liner industry. Progress in experimental tasks on chemical resistance of liners, physical properties of liners, and nondestructive examination of seams is reported. 25 references, 9 figures, 13 tables.

  11. The origins of liner material in a shaped charge jet particle

    SciTech Connect

    Zernow, L.; Chapyak, E.J.; Meyer, K.A.; Zernow, R.H.

    1992-02-01

    An improved high resolution LaGrangean tracer particle technique (using 198 identified tracer particles arranged as 99 particle pairs) has been used with an Eulerian Code (MESA 2D) to determine the locations in the jet to which liner material flows from various tagged locations in the liner, during the collapse, jet formation and jet stretching process. Time dependent strain and strain rate data has been computed, using the identified particle pairs of LaGrangean tracer particles as linear strain gauges. Sharp radial gradients of strain and strain rate have been found in the jet, with the liner material flowing nearest the jet axis being subjected to the highest strains and strain rates. Liner material from many extended initial locations along the liner can be traced by this method to jet locations corresponding to individual jet particles. The new quantitative data derived is illustrated with selected examples whose interpretation is discussed.

  12. The origins of liner material in a shaped charge jet particle

    SciTech Connect

    Zernow, L. ); Chapyak, E.J.; Meyer, K.A. ); Zernow, R.H. )

    1992-01-01

    An improved high resolution LaGrangean tracer particle technique (using 198 identified tracer particles arranged as 99 particle pairs) has been used with an Eulerian Code (MESA 2D) to determine the locations in the jet to which liner material flows from various tagged locations in the liner, during the collapse, jet formation and jet stretching process. Time dependent strain and strain rate data has been computed, using the identified particle pairs of LaGrangean tracer particles as linear strain gauges. Sharp radial gradients of strain and strain rate have been found in the jet, with the liner material flowing nearest the jet axis being subjected to the highest strains and strain rates. Liner material from many extended initial locations along the liner can be traced by this method to jet locations corresponding to individual jet particles. The new quantitative data derived is illustrated with selected examples whose interpretation is discussed.

  13. Reaching High-Yield Fusion with a Slow Plasma Liner Compressing a Magnetized Target

    SciTech Connect

    Ryutov, D D; Parks, P B

    2008-03-18

    Dynamics of the compression of a magnetized plasma target by a heavy liner made of partially ionized high high-Z material is discussed. A 'soft-landing' (shockless) mode of the liner deceleration is analyzed. Conclusion is drawn that such mode is possible for the liners whose thickness at the time of the first contact with the target is smaller than, roughly, 10% of the initial (un-compressed) target radius. A combination of the plasma liner with one or two glide cones allows for a direct access to the area near the center of the reactor chamber. One can then generate plasma target inside the plasma liner at the optimum time. The other advantage of the glide cones is that they can be used to deliver additional fuel to the center of the target near the point of a maximum compression and thereby increase the fusion yield.

  14. Using nonlinear optimization methods to reverse engineer liner material properties from EFP tests

    SciTech Connect

    Murphy, M.J.; Baker, E.L.

    1995-02-27

    The utility of variable metric nonlinear optimization methods for reverse engineering liner material constitutive modeling parameters is described. We use an effective new code created by coupling the nonlinear optimization code NLQPEB with the DYNA2D finite element hydrocode. The optimization code determines the ``best`` set of liner material properties by running DYNA2D in a loop, varying the liner model constitutive parameters, and minimizing the difference between the EFP profiles of the calculation and experiment. The results of four different EFP warhead tests with the same copper liner material are used to determine material parameters for the Steinberg-Guinan, Johnson-Cook, & Armstrong-Zerilli models. In a companion paper we describe the successful application of this methodology to the forward engineering of liner contours to achieve desired EFP shapes. The methodology of utilizing a coupled optimization/finite element code provides a significant improvement in warhead designs and the warhead design process.

  15. Clinical performance of Class I nanohybrid composite restorations with resin-modified glass-ionomer liner and flowable composite liner: A randomized clinical trial

    PubMed Central

    Suhasini, Krishtipati; Madhusudhana, Koppolu; Suneelkumar, Chinni; Lavanya, Anumula; Chandrababu, K. S.; Kumar, Perisetty Dinesh

    2016-01-01

    Background: Liners play a vital role in minimizing polymerization shrinkage stress by elastic bonding concept and increase the longevity and favorable outcome for composite restorations. Aims: The aim of this study was to evaluate the clinical performance of nanohybrid composite restorations using resin-modified glass-ionomer and flowable composite liners. Settings and Design: A single-centered, double-blinded randomized clinical trial, with split-mouth design and equal allocation ratio that was conducted in the Department of Conservative Dentistry and Endodontics. Materials and Methods: In forty patients, a total of eighty Class I restorations were placed with resin-modified glass-ionomer cement (RMGIC) liner (FUJI II LC, GC America) in one group and flowable composite liner (smart dentin replacement/SDR, Dentsply Caulk, Milford, DE, USA) in another group. All restorations were clinically evaluated by two examiners, immediately (baseline), 3, 6, and 12 months using US Public Health Service modified criteria. Statistical Analysis Used: Statistical analysis was performed using McNemar's test (P < 0.05). Results: There was no significant difference in the color match, marginal discoloration, surface roughness, and marginal adaptation. Restorations with RMGIC liner group show 20% Bravo scores on anatomic form at 12 months but are still clinically acceptable. Conclusion: Nanohybrid composite restorations with RMGIC (Fuji II LC) and flowable composite liner (SDR) demonstrated clinically acceptable performance after 12 months. PMID:27994310

  16. Active containment systems incorporating modified pillared clays

    SciTech Connect

    Lundie, P. |; McLeod, N.

    1997-12-31

    The application of treatment technologies in active containment systems provides a more advanced and effective method for the remediation of contaminated sites. These treatment technologies can be applied in permeable reactive walls and/or funnel and gate systems. The application of modified pillared clays in active containment systems provides a mechanism for producing permeable reactive walls with versatile properties. These pillared clays are suitably modified to incorporate reactive intercalatants capable of reacting with both a broad range of organic pollutants of varying molecular size, polarity and reactivity. Heavy metals can be removed from contaminated water by conventional ion-exchange and other reactive processes within the clay structure. Complex contamination problems can be addressed by the application of more than one modified clay on a site specific basis. This paper briefly describes the active containment system and the structure/chemistry of the modified pillared clay technology, illustrating potential applications of the in-situ treatment process for contaminated site remediation.

  17. Permeation properties of polymer/clay nanocomposites

    NASA Astrophysics Data System (ADS)

    Kalendova, A.; Merinska, D.; Gerard, J. F.

    2012-07-01

    The important characteristics of polymer/clay nanocomposites are stability, barrier properties and in the case of polyvinyl chloride also plasticizer migration into other materials. Therefore, the permeation properties of polymer/clay nanocomposites are discussed in this paper. The attention was focused to the polyethylene (PE) and polyvinyl chloride (PVC). Natural type of montmorillonite MMTNa+ and modified types of montmorillonite from Southern Clay Products were used as the inorganic phase. As the compounding machine, one screw Buss KO-kneader was employed. The principal aim is to fully exfoliate the clay into polymer matrix and enhanced the permeation properties. Prepared samples were tested for O2 and CO2 permeability. Polymer/clay nanocomposite structure was determined on the base of X-ray diffraction and electron microscopy (TEM).

  18. Multifaceted role of clay minerals in pharmaceuticals

    PubMed Central

    Khurana, Inderpreet Singh; Kaur, Satvinder; Kaur, Harpreet; Khurana, Rajneet Kaur

    2015-01-01

    The desirable physical and physiochemical properties of clay minerals have led them to play a substantial role in pharmaceutical formulations. Clay minerals like kaolin, smectite and palygorskite-sepiolite are among the world's most valuable industrial minerals and of considerable importance. The elemental features of clay minerals which caused them to be used in pharmaceutical formulations are high specific area, sorption capacity, favorable rheological properties, chemical inertness, swelling capacity, reactivity to acids and inconsiderable toxicity. Of course, these are highly cost effectual. This special report on clay minerals provides a bird's eye view of the chemical composition and structure of these minerals and their influence on the release properties of active medicinal agents. Endeavor has been made to rope in myriad applications depicting the wide acceptability of these clay minerals. PMID:28031881

  19. Release kinetics of volatiles from clay minerals

    NASA Astrophysics Data System (ADS)

    Clausen, Pascal

    2007-03-01

    Smectite clay minerals are known to have interesting sorption properties, but the prediction of the kinetics of desorption of volatile molecules from such clays remains a challenge. The aim of this work is to relate the isothermal rate of desorption of volatile molecules from cation exchanged smectite clays to the chemical structures and geometries of the interacting species (clay platelet surface, type of counter-ion, type of volatile). It is thought that the rate of desorption of the volatiles at a given time is governed by their instantaneous diffusion in the clay and in the gas phase, which in turns is dependent on the volatile's interaction with its chemical and geometrical environment. Therefore, in addition to isothermal desorption rate measurements by thermogravimetry, activation energies of desorption are measured and calculated and the interacting compounds are characterized in terms of their chemical structure and geometry.

  20. Clays and other minerals in prebiotic processes

    NASA Technical Reports Server (NTRS)

    Paecht-Horowitz, M.

    1984-01-01

    Clays and other minerals have been investigated in context with prebiotic processes, mainly in polymerization of amino acids. It was found that peptides adsorbed on the clay, prior to polymerization, influence the reaction. The ratio between the amount of the peptides adsorbed and that of the clay is important for the yield as well as for the degrees of polymerization obtained. Adsorption prior to reaction produces a certain order in the aggregates of the clay particles which might induce better reaction results. Excess of added peptides disturbs this order and causes lesser degrees of polymerization. In addition to adsorption, clays are also able to occlude between their layers substances out of the environment, up to very high concentrations.

  1. Development of improved performance refractory liner materials for slagging gasifiers

    SciTech Connect

    Kwong, Kyei-Sing; Bennett, James P.; Powell, Cynthia; Thomas, Hugh; Krabbe, Rick

    2005-01-01

    Refractory liners for slagging gasifiers used in power generation, chemical production, or as a possible future source of hydrogen for a hydrogen based economy, suffer from a short service life. These liner materials are made of high Cr2O3 and lower levels of Al2O3 and/or ZrO2. As a working face lining in the gasifier, refractories are exposed to molten slags at elevated temperature that originate from ash in the carbon feedstock, including coal and/or petroleum coke. The molten slag causes refractory failure by corrosion dissolution and by spalling. The Albany Research Center is working to improve the performance of Cr2O3 refractories and to develop refractories without Cr2O3 or with Cr2O3 content under 30 wt pct. Research on high Cr2O3 materials has resulted in an improved refractory with phosphate additions that is undergoing field testing. Results to date of field trials, along with research direction on refractories with no or low Cr2O3, will be discussed.

  2. A duty cycle hypothesis for the central engines of LINERs

    NASA Technical Reports Server (NTRS)

    Eracleous, Michael; Livio, Mario; Binete, Luc

    1995-01-01

    A recent ultraviolet snaphsot imaging survey of the nuclei of nearby galaxies detected a compact nuclear ultraviolet source in only five of the 26 LINERs (low-ionization nuclear emission-line regions) included in the observed sample. Motivated by this observational result, we examine the possibility that all LINERs are powered by photoionization from a nuclear source, which is, however, active only for 20% of the time. We show that decay times of low-ionization species can be of the order of one to a few centuries, and we demonstrate through time-dependent photoionization calculations that if the nuclear ionizing source is active for only a fraction of the time, this would not be readily noticeable in the emission-line spectrum. We suggest that the activity cycle is related to episodic accretion events which are associated with the tidal disruption of stars by a central black hole. The time interval between tidal disruptions is of the same order as the emission-line decay time, with the accretion episode following each disruption lasting a few decades. These estimates appear to support the duty cycle hypothesis. Some observational consequences of the proposed scenario are also discussed.

  3. 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.

  4. Plasma Guns for the Plasma Liner Experiment (PLX)

    NASA Astrophysics Data System (ADS)

    Witherspoon, F. D.; Bomgardner, R.; Case, A.; Messer, S. J.; Brockington, S.; Wu, L.; Elton, R.; Hsu, S. C.; Cassibry, J. T.; Gilmore, M. A.

    2009-11-01

    A spherical array of minirailgun plasma accelerators is planned for the Plasma Liner Experiment (PLX) to be located at LANL. The plasma liner would be formed via merging of 30 dense, high Mach number plasma jets (n˜10^16-17 cm-3, M˜10--35, v˜50--70 km/s, rjet˜5 cm) in a spherically convergent geometry. Small parallel-plate railguns are being developed for this purpose due to their reduced system complexity and cost, with each gun planned to operate at ˜300 kA peak current, and launching up to ˜8000 μg of high-Z plasma using a ˜50 kJ pfn. We describe experimental development of the minirailguns and their current and projected performance. Fast operating repetitive gas valves have recently been added to allow injection of high density gases including helium, argon, and (eventually) xenon. We will present the latest test results with the high-Z gases, and discuss future plans for augmenting the rails, optimizing the nozzle configuration, preionizing the injected gas, and configuring the pulse forming networks with the capacitors available to the program.

  5. Liner evaluation for uranium mill tailings. Final report

    SciTech Connect

    Buelt, J.L.

    1983-09-01

    The Liner Evaluation for Uranium Mill Tailings Program was conducted to evaluate the need for and performance of prospective lining materials for the long-term management of inactive uranium mill tailings piles. On the basis of program results, two materials have been identified: natural foundation soil amended with 10% sodium bentonite; catalytic airblown asphalt membrane. The study showed that, for most situations, calcareous soils typical of Western US sites adequately buffer tailings leachates and prevent groundwater contamination without additional liner materials or amendments. Although mathematical modeling of disposal sites is recommended on a site-specific basis, there appears to be no reason to expect significant infiltration through the cover for most Western sites. The major water source through the tailings would be groundwater movement at sites with shallow groundwater tables. Even so column leaching studies showed that contaminant source terms were reduced to near maximum contaminant levels (MCL's) for drinking water within one or two pore volumes; thus, a limited source term for groundwater contamination exists. At sites where significant groundwater movement or infiltration is expected and the tailings leachates are alkaline, however, the sodium bentonite or asphalt membrane may be necessary.

  6. FIREBALL: Fusion Ignition Rocket Engine with Ballistic Ablative Lithium Liner

    SciTech Connect

    Martin, Adam K.; Eskridge, Richard H.; Lee, Michael H.; Fimognari, Peter J.

    2006-01-20

    Thermo-nuclear fusion may be the key to a high Isp, high specific power 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 dense FRC plasmoid is accelerated to high velocity (in excess of 500 km/s) and is compressed into a detached liner (pulse unit). The kinetic energy of the FRC is converted into thermal and magnetic-field energy, igniting a fusion burn 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 a pusher-plate, as in the classic Orion concept. However with this concept, the vehicle does not carry a magazine of autonomous pulse-units. By accelerating a second, heavier FRC, which acts as a piston, right behind the first one, the velocity required to initiate the fusion burn is greatly reduced.

  7. Polyethylene liner cementation technique in asymptomatic versus symptomatic osteolysis.

    PubMed

    Kandel, Leonid; Rivkin, Gurion; Friedman, Adi; Segal, David; Liebergall, Meir; Mattan, Yoav

    2009-08-01

    Osteolysis around a cementless acetabular component can lead to severe bone loss. This study examined whether osteolysis should be treated while still asymptomatic. Thirty-seven liner cementation revisions were performed in 34 patients. Mean patient age was 61 years, and mean time elapsed after index surgery was 85 months (range, 36-168 months). Patients were evaluated by Harris Hip Score (HHS), and mean follow-up was 5 years (range, 43-82 months). Average HHS was 87 with a pain component of 39. In asymptomatic patients, both the HHS and the pain score were significantly higher: 95 and 43, respectively (P<.01). One patient with extensive bone loss had a fracture of the acetabulum and underwent revision at another institution. Revision of the polyethylene liner and cementation of a new one is a useful technique in patients with a stable acetabular shell. This is especially true for asymptomatic patients with osteolysis and thus should be performed early; however, high dislocation rate is still a concern.

  8. Effect of the local clay distribution on the effective electrical conductivity of clay rocks

    NASA Astrophysics Data System (ADS)

    Cosenza, P.; Prêt, D.; Zamora, M.

    2015-01-01

    The "local porosity theory" proposed by Hilfer was revisited to develop a "local clay theory" (LCT) that establishes a quantitative relationship between the effective electrical conductivity and clay distribution in clay rocks. This theory is primarily based on a "local simplicity" assumption; under this assumption, the complexity of spatial clay distribution can be captured by two local functions, namely, the local clay distribution and the local percolation probability, which are calculated from a partitioning of a mineral map. The local clay distribution provides information about spatial clay fluctuations, and the local percolation probability describes the spatial fluctuations in the clay connectivity. This LCT was applied to (a) a mineral map made from a Callovo-Oxfordian mudstone sample and (b) (macroscopic) electrical conductivity measurements performed on the same sample. The direct and inverse modeling shows two results. First, the textural and classical model assuming that the electrical anisotropy of clay rock is mainly controlled by the anisotropy of the sole clay matrix provides inconsistent inverted values. Another textural effect, the anisotropy induced by elongated and oriented nonclayey grains, should be considered. Second, the effective conductivity values depend primarily on the choice of the inclusion-based models used in the LCT. The impact of local fluctuations of clay content and connectivity on the calculated effective conductivity is lower.

  9. Formation of imploding plasma liners for fundamental HEDP studies and MIF Standoff Driver Concept

    SciTech Connect

    Cassibry, Jason; Hatcher, Richard; Stanic, Milos

    2013-08-17

    The disciplines of High Energy Density Physics (HEDP) and Inertial Confinement Fusion (ICF) are characterized by hypervelocity implosions and strong shocks. The Plasma Liner Experiment (PLX) is focused on reaching HEDP and/or ICF relevant regimes in excess of 1 Mbar peak pressure by the merging and implosion of discrete plasma jets, as a potentially efficient path towards these extreme conditions in a laboratory. In this work we have presented the first 3D simulations of plasma liner, formation, and implosion by the merging of discrete plasma jets in which ionization, thermal conduction, and radiation are all included in the physics model. The study was conducted by utilizing a smoothed particle hydrodynamics code (SPHC) and was a part of the plasma liner experiment (PLX). The salient physics processes of liner formation and implosion are studied, namely vacuum propagation of plasma jets, merging of the jets (liner forming), implosion (liner collapsing), stagnation (peak pressure), and expansion (rarefaction wave disassembling the target). Radiative transport was found to significantly reduce the temperature of the liner during implosion, thus reducing the thermal leaving more pronounced gradients in the plasma liner during the implosion compared with ideal hydrodynamic simulations. These pronounced gradients lead to a greater sensitivity of initial jet geometry and symmetry on peak pressures obtained. Accounting for ionization and transport, many cases gave higher peak pressures than the ideal hydrodynamic simulations. Scaling laws were developed accordingly, creating a non-dimensional parameter space in which performance of an imploding plasma jet liner can be estimated. It is shown that HEDP regimes could be reached with ~ 5 MJ of liner energy, which would translate to roughly 10 to 20 MJ of stored (capacitor) energy. This is a potentially significant improvement over the currently available means via ICF of achieving HEDP and nuclear fusion relevant parameters.

  10. Interfacial interactions between polyethylene matrix and clay layers in polyethylene/clay nanocomposites

    NASA Astrophysics Data System (ADS)

    Abu-Zurayk, R.

    2015-10-01

    Polyethylene/clay nanocomposites were prepared as blown films using different formulae (clay contents (4 and 6 wt%) and compatibilizer/clay ratio (1/2, 1.0, 2.0)). Structure and mechanical behaviour were tested. It was found that blown film extrusion process decreased the tactoids size and consequently enhanced the exfoliation degree of the clay layers inside the polymer matrix, which is due to the elongational stress during extrusion. Addition of clay had some effects on mechanical behaviour. There was an increase of yield strength (max 32%). Yield strength is related to the interfacial interaction between the polymer and the clay layers in the nanocomposites, which would be enhanced by enhancing the compatibility between polymer and clay layers. Correlation analysis showed good correlation between compatibility and interfacial interaction parameters, and between parameters of interfacial interaction, structure and yield strength.

  11. First-exposure performance of the bentonite component of a GCL in a low-pH, calcium-enriched environment

    SciTech Connect

    Quaranta, J.D.; Gabr, M.A.; Bowders, J.J.

    1997-11-01

    Testing was conducted on the bentonite portion of a Geosynthetic Clay Liner (GCL) for application to an environment characterized as having high concentrations of dissolved calcium ions. This environment presents conditions that might affect the long-term hydraulic function of the GCL as a component in a barrier system. Experiments were conducted to investigate first-exposure compatibility of a sodium bentonite GCL subject to the affects of acidic groundwater and second from the combined affects of acidic groundwater enriched with calcium. Relationships between the ionic exchange of sodium, potassium, magnesium and calcium species in the bentonite, and changes in hydraulic conductivity and electrical conductance are reported and discussed.

  12. Phosphates in some missouri refractory clays

    USGS Publications Warehouse

    Hall, R.B.; Foord, E.E.; Keller, D.J.; Keller, W.D.

    1997-01-01

    This paper describes in detail phosphate minerals occurring in refractory clays of Missouri and their effect on the refractory degree of the clays. The minerals identified include carbonate-fluorapatite (francolite), crandallite, goyazite, wavellite, variscite and strengite. It is emphasized that these phosphates occur only in local isolated concentrations, and not generally in Missouri refractory clays. The Missouri fireclay region comprises 2 districts, northern and southern, separated by the Missouri River In this region, clay constitutes a major part of the Lower Pennsylvanian Cheltenham Formation. The original Cheltenham mud was an argillic residue derived from leaching and dissolution of pre-Pennsylvanian carbonates. The mud accumulated on a karstic erosion surface truncating the pre-Cheltenham rocks. Fireclays of the northern district consist mainly of poorly ordered kaolinite, with variable but minor amounts of illite, chlorite and fine-grained detrital quartz. Clays of the southern district were subjected to extreme leaching that produced well-ordered kaolinite flint clays. Local desilication formed pockets of diaspora, or more commonly, kaolinite, with oolite-like nubs or burls of diaspore ("burley" clay). The phosphate-bearing materials have been studied by X-ray diffraction (XRD), scanning electron microscopy-energy dispersive spectral analysis (SEM-EDS) and chemical analysis. Calcian goyazite was identified in a sample of diaspore, and francolite in a sample of flint clay. A veinlet of wavellite occurs in flint clay at one locality, and a veinlet of variscite-strengite at another locality. The Missouri flint-clay-hosted francolite could not have formed in the same manner as marine francolite The evidence suggests that the Cheltenham francolite precipitated from ion complexes in pore water nearly simultaneously with crystallization of kaolinite flint clay from an alumina-silica gel. Calcian goyazite is an early diagenetic addition to its diaspore host

  13. Critical review of coupled flux formulations for clay membranes based on nonequilibrium thermodynamics.

    PubMed

    Malusis, Michael A; Shackelford, Charles D; Maneval, James E

    2012-09-01

    Extensive research conducted over the past several decades has indicated that semipermeable membrane behavior (i.e., the ability of a porous medium to restrict the passage of solutes) may have a significant influence on solute migration through a wide variety of clay-rich soils, including both natural clay formations (aquitards, aquicludes) and engineered clay barriers (e.g., landfill liners and vertical cutoff walls). Restricted solute migration through clay membranes generally has been described using coupled flux formulations based on nonequilibrium (irreversible) thermodynamics. However, these formulations have differed depending on the assumptions inherent in the theoretical development, resulting in some confusion regarding the applicability of the formulations. Accordingly, a critical review of coupled flux formulations for liquid, current, and solutes through a semipermeable clay membrane under isothermal conditions is undertaken with the goals of explicitly resolving differences among the formulations and illustrating the significance of the differences from theoretical and practical perspectives. Formulations based on single-solute systems (i.e., uncharged solute), single-salt systems, and general systems containing multiple cations or anions are presented. Also, expressions relating the phenomenological coefficients in the coupled flux equations to relevant soil properties (e.g., hydraulic conductivity and effective diffusion coefficient) are summarized for each system. A major difference in the formulations is shown to exist depending on whether counter diffusion or salt diffusion is assumed. This difference between counter and salt diffusion is shown to affect the interpretation of values for the effective diffusion coefficient in a clay membrane based on previously published experimental data. Solute transport theories based on both counter and salt diffusion then are used to re-evaluate previously published column test data for the same clay membrane

  14. Quantification of prosthetic outcomes: elastomeric gel liner with locking pin suspension versus polyethylene foam liner with neoprene sleeve suspension.

    PubMed

    Coleman, Kim L; Boone, David A; Laing, Linda S; Mathews, David E; Smith, Douglas G

    2004-07-01

    For this randomized crossover trial, we compared two common transtibial socket suspension systems: the Alpha liner with distal locking pin and the Pe-Lite liner with neoprene suspension sleeve. Our original hypotheses asserted that increased ambulatory activity, wear time, comfort, and satisfaction would be found with the elastomeric suspension system. Thirteen subjects completed the study. Following 2.5-month accommodation to each condition, ambulatory activity was recorded (steps/minute for 2 weeks), and subjects completed three questionnaires specific to prosthesis use and pain: the Prosthesis Evaluation Questionnaire (PEQ), a Brief Pain Inventory (BPI) excerpt, and the Socket Comfort Score (SCS). Upon completion, subjects selected their favored system for continued use. Ten subjects preferred the Pe-Lite and three the Alpha. Subjects spent 82% more time wearing the Pe-Lite and took 83% more steps per day. Ambulatory intensity distribution did not differ between systems. No statistically significant differences were found in questionnaire results. Subject feedback for each system was both positive and negative.

  15. Fine particle clay catalysts for coal liquefaction

    SciTech Connect

    Olson, E.S.

    1991-01-01

    The efficient production of environmentally acceptable distillate fuels requires catalysts for hydrogenation and cleavage of the coal macromolecules and removal of oxygen, nitrogen, and sulfur heteroatoms. The goal of the proposed research is to develop new catalysts for the direct liquefaction of coal. This type of catalyst consists of fine clay particles that have been treated with reagents which form pillaring structures between the aluminosilicate layers of the clay. The pillars not only hold the layers apart but also constitute the active catalytic sites for hydrogenation of the coal and the solvent used in the liquefaction. The pillaring catalytic sites are composed of pyrrhotite, which has been previously demonstrated to be active for coal liquefaction. The pyrrhotite sites are generated in situ by sulfiding the corresponding oxyiron species. The size of the catalyst will be less than 40 nm in order to promote intimate contact with the coal material. Since the clays and reagents for pillaring and activating the clays are inexpensive, the catalysts can be discarded after use, rather than regenerated by a costly process. The proposed work will evaluate methods for preparing the fine particle iron-pillared clay dispersions and for activating the particles to generate the catalysts. Characterization studies of the pillared clays and activated catalysts will be performed. The effectiveness of the pillared clay dispersion for hydrogenation and coal liquefaction will be determined in several types of testing.

  16. Fine particle clay catalysts for coal liquefaction

    SciTech Connect

    Olson, E.S.

    1991-01-01

    The efficient production of environmentally acceptable distillate fuels requires catalysts for hydrogenation and cleavage of the coal macromolecules and removal of oxygen, nitrogen, and sulfur heteroatoms. The goal of the proposed research is to develop new catalysts for the direct liquefaction of coal. This type of catalyst consists of fine clay particles that have been treated with reagents which form pillaring structures between the aluminosilicate layers of the clay. The pillars not only hold the layers apart but also constitute the active catalytic sites for hydrogenation of the coal and solvent used in the liquefaction. The pillaring catalytic sites are composed of pyrrhotite, which has been previously demonstrated to be active for coal liquefaction. The pyrrhotite sites are generated in situ by sulfiding the corresponding oxyiron species. The size of the catalyst will be less than 40 nm in order to promote intimate contact with the coal material. Since the clays and reagents for pillaring and activating the clays are inexpensive, the catalysts can be discarded after use, rather than regenerated by a costly process. The proposed work will evaluate methods for preparing the fine particle iron-pillared clay dispersions and for activating the particles to generate the catalysts. Characterization studies of the pillared clays and activated catalysts will performed. The effectiveness of the pillared clay dispersion for hydrogenation and coal liquefaction will be determined in several types of testing. 5 refs., 1 tab.

  17. 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.

  18. Beryllium liner z-pinches for Magneto-Rayleigh--Taylor studies on Z.

    SciTech Connect

    McBride, Ryan D.; Martin, Matthew Ryan; Vesey, Roger Alan; Lemke, Raymond William; Sinars, Daniel Brian; Herrmann, Mark C.; Jennings, Christopher A.; Cuneo, Michael Edward; Slutz, Stephen A.

    2010-12-01

    Magnetic Liner Inertial Fusion (MagLIF) [S. A. Slutz, et al., Phys. Plasmas 17 056303 (2010)] is a promising new concept for achieving >100 kJ of fusion yield on Z. The greatest threat to this concept is the Magneto-Rayleigh-Taylor (MRT) instability. Thus an experimental campaign has been initiated to study MRT growth in fast-imploding (<100 ns) cylindrical liners. The first sets of experiments studied aluminum liner implosions with prescribed sinusoidal perturbations (see talk by D. Sinars). By contrast, this poster presents results from the latest sets of experiments that used unperturbed beryllium (Be) liners. The purpose for using Be is that we are able to radiograph 'through' the liner using the 6-keV photons produced by the Z-Beamlet backlighting system. This has enabled us to obtain time-resolved measurements of the imploding liner's density as a function of both axial and radial location throughout the field of view. This data is allowing us to evaluate the integrity of the inside (fuel-confining) surface of the imploding liner as it approaches stagnation.

  19. Construction and performance of a long-term earthen liner experiment

    USGS Publications Warehouse

    Cartwright, Keros; Krapac, Ivan G.; Bonaparte, Rudolph

    1990-01-01

    In land burial schemes, compacted soil barriers with low hydraulic conductivity are commonly used in cover and liner systems to control the movement of liquids and prevent groundwater contamination. An experimental liner measuring 8 x 15 x 0.9 m was constructed with design criteria and equipment to simulate construction of soil liners built at waste disposal facilities. The surface of the liner was flooded with a 29.5 cm deep pond on April 12, 1988. Infiltration of water into the liner has been monitored for two years using 4 large-ring (1.5 m OD) and 32 small-ring (0.28 m OD) infiltrometers, and a water-balance that accounts for total infiltration and evaporation. Average long-term infiltration fluxes based on two years of monitoring are 5.8 x 10-9 cm/s, 6.0 x 10-8 cm/s and 5.6 x 10-8 for the large-ring, small-ring, and water-balance data, respectively. The saturated hydraulic conductivity of the liner based on small-ring data, estimated using Darcy's Law and the Green-Ampt Approximation, is 3 x 10-8 and 4 x 10-8 cm/s, respectively. All sets of data indicate that the liner's performance exceed that which is required by the U.S. EPA.

  20. Imploding Liner Material Strength Measurements at High-Strain and High Strain Rate

    SciTech Connect

    Bartsch, R.R.; Lee, H.; Holtkamp, D.; Wright, B.; Stokes, J.; Morgan, D.; Anderson, W.; Broste, W.

    1998-10-18

    Imploding, cylindrical liners provide a unique, shockless means of simultaneously accessing high strain and high-strain-rate for measurement of strength of materials in plastic flow. The radial convergence in the liner geometry results in the liner thickening as the circumference becomes smaller. Strains of up to {approximately}1.25 and strain rates of up to {approximately}10{sup 6} sec{sup -1} can be readily achieved in a material sample placed inside of an aluminum driver liner, using the Pegasus II capacitor bank. This provides yield strength data at conditions where none presently exists. The heating from work done against the yield strength is measured with multichannel pyrometry from infrared radiation emitted by the material sample. The temperature data as a function of liner position are unfolded to give the yield strength along the strain, strain-rate trajectory. Proper design of the liner and sample configuration ensures that the current diffused into the sample adds negligible heating. An important issue, in this type of temperature measurement, is shielding of the pickup optics from other sources of radiation. At strains greater than those achievable on Pegasus, e.g. the LANL Atlas facility, some materials may be heated all the way to melt by this process. Recent data on 6061-T6 Aluminum will be compared with an existing model for strain and strain-rate heating. The liner configuration and pyrometry diagnostic will also be discussed.

  1. The Fusion Gain Analysis of the Inductively Driven Liner Compression Based Fusion

    NASA Astrophysics Data System (ADS)

    Shimazu, Akihisa; Slough, John

    2016-10-01

    An analytical analysis of the fusion gain expected in the inductively driven liner compression (IDLC) based fusion is conducted to identify the fusion gain scaling at various operating conditions. The fusion based on the IDLC is a magneto-inertial fusion concept, where a Field-Reversed Configuration (FRC) plasmoid is compressed via the inductively-driven metal liner to drive the FRC to fusion conditions. In the past, an approximate scaling law for the expected fusion gain for the IDLC based fusion was obtained under the key assumptions of (1) D-T fuel at 5-40 keV, (2) adiabatic scaling laws for the FRC dynamics, (3) FRC energy dominated by the pressure balance with the edge magnetic field at the peak compression, and (4) the liner dwell time being liner final diameter divided by the peak liner velocity. In this study, various assumptions made in the previous derivation is relaxed to study the change in the fusion gain scaling from the previous result of G ml1 / 2 El11 / 8 , where ml is the liner mass and El is the peak liner kinetic energy. The implication from the modified fusion gain scaling on the performance of the IDLC fusion reactor system is also explored.

  2. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

    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.

  4. Acoustic scattering by an axially-segmented turbofan inlet duct liner at supersonic fan speeds

    NASA Astrophysics Data System (ADS)

    McAlpine, A.; Astley, R. J.; Hii, V. J. T.; Baker, N. J.; Kempton, A. J.

    2006-07-01

    Fan noise is one of the principal noise sources in turbofan aero-engines. At supersonic fan speeds, fan tones are generated by the "rotor-alone" pressure field. In general, these tones can be well absorbed by an inlet duct acoustic liner, except at high supersonic fan speeds when the rotor-alone pressure field is well cut-on. In this article an axially segmented liner is proposed, which is predicted to improve the attenuation of tones at high supersonic fan speeds. The analysis is based on locally reacting cavity liners. The axially segmented liner is axisymmetric and consists of two circular sections of different linings joined together. The optimum design consists of two linings with the same face-sheet resistance, but with different cavity depths. The depth of the liner adjacent to the fan is very thin. This means that where the two liners are joined there is a wall impedance discontinuity that can cause acoustic scattering. Fan tones can be modelled in terms of spinning modes in a uniform circular-section duct. The liner is axisymmetric, so modal scattering will be only between different radial modes. The optimum design minimizes the acoustic energy scattered into the first radial mode. This improves the attenuation of fan tones at high supersonic fan speeds, because acoustic energy is scattered into high radial mode orders, which are better absorbed by the lining.

  5. Optimization of deformations and hoop stresses in TSV liners to boost interconnect reliability in electronic appliances

    NASA Astrophysics Data System (ADS)

    Juma, Mary Atieno; Zhang, Xuliang; He, Song Bai; Abusabah, Ahmed I. A.

    2015-12-01

    Recently, there has been a lot of research with electronic products because more and different functions are integrated into devices and the final product sizes have to be small to meet the market demand. A lot of research has been done on the (TSVs) Through Silicon Vias. In this paper, through silicon via liners are investigated. The liners: silicon dioxide, polystyrene and polypropylene carbonate are exposed to pressure on their inner surfaces and this yielded hoop stresses within their thickness. Deflections too occurred and this is a proof that deformation really took place. In one of our papers, hoop stresses for the same materials were investigated. The values were a little higher but different for each material used. In this paper, we use global cylindrical, partial cylinder model with different theta in Analysis system 14 to model the through silicon via liners. The values are lower meaning the reliability of the liners have been optimized and boosted. However, silicon dioxide liner had the lowest hoop stress around its circumference and lowest deflection value meaning that it's still one of the most reliable materials in the manufacture of through silicon via liners in the industry; but overdependence can be avoided if the other liners are used too.

  6. Hard X-Ray Emission and the Ionizing Source in LINERs

    NASA Technical Reports Server (NTRS)

    Terashima, Yuichi; Ho, Luis C.; Ptak, Andrew F.

    2000-01-01

    We report X-ray fluxes in the 2-10 keV band from LINERs (low-ionization nuclear emission-line regions) and low-luminosity Seyfert galaxies obtained with the ASCA satellite. Observed X-ray luminosities are in the range between 4 x 10(exp 39) and 5 x 10(exp 41) ergs/s, which are significantly smaller than that of the "classical" low-luminosity Seyfert 1 galaxy NGC 4051. We found that X-ray luminosities in 2-10 keV of LINERs with broad H.alpha emission in their optical spectra (LINER 1s) are proportional to their Ha luminosities. This correlation strongly supports the hypothesis that the dominant ionizing source in LINER 1s is photoionization by hard photons from low-luminosity AGNs. On the other hand, the X-ray luminosities of most LINERs without broad H.alpha emission (LINER 2s) in our sample are lower than LINER 1s at a given H.alpha luminosity. The observed X-ray luminosities in these objects are insufficient to power their H.alpha luminosities, suggesting that their primary ionizing source is other than an AGN, or that an AGN, if present, is obscured even at energies above 2 keV.

  7. Highly cross-linked polyethylene acetabular liners retrieved four to five years after revision surgery: a report of two cases.

    PubMed

    Teeter, Matthew G; Naudie, Douglas D R; Charron, Kory D; Holdsworth, David W

    2010-08-01

    There is currently considerable interest in the use of highly cross-linked polyethylene (XLPE) acetabular liners for total hip arthroplasty (THA). In literature, only a single retrieval analysis of one type of XLPE liner implanted for greater than four years exists. The purpose of the present report is to quantify surface deviations in two XLPE liners implanted during revision THA and retrieved between four to five years after implantation. The two XLPE acetabular liners (Reflection, Smith and Nephew Inc., Memphis, TN) were retrieved from patients undergoing their second revision surgery, at 4.90 and 4.07 years. The retrieved liners and a new, non-implanted, unworn liner of the same size were scanned using micro-computed tomography (micro-CT). Articular surface deviation maps were created by comparing the retrievals to the unworn liner, based on the liner geometry obtained from micro-CT. The linear penetration rates were found to be 0.018 and 0.008 mm/year. Localized scratches and pits with deviations greater than 0.205 mm were also found on the articular surfaces of both liners. The XLPE liners retrieved from the two cases demonstrated low linear penetration rates. Regions with greater focal deviations were also apparent, likely due to third-body wear. The results are consistent with previously published clinical follow-ups of other XLPE liners.

  8. Target compressions by working fluids driven with solid liner implosions

    NASA Technical Reports Server (NTRS)

    Chiang, P.-R.; Lewis, R. A.; Smith, G. A.; Dailey, J. M.; Chakrabarti, S.; Higman, K. I.; Bell, D.; Degnan, J. H.; Hussey, T. W.; Mullins, B. W.

    1994-01-01

    Compression by a spherical solid liner of a gold target surrounded by a hydrogen plasma is simulated. Two-dimensional simulations that treat only a subset of the physics included in the one-dimensional code were performed in an attempt to assess multidimensional effects. A one-dimensional numerical code has been developed to study the effects of thermal radiation and conduction. Results of pressure, density, and energy deposited for different initial plasma conditions are presented and discussed. Results from both one- and two-dimensional codes show that the average target density at peak compression is 39-43 g/cu cm, using the SHIVA Star facility at 90 kV discharge.

  9. Nonlinear Laser-Plasma Interaction in Magnetized Liner Inertial Fusion

    SciTech Connect

    Geissel, Matthias; Awe, Thomas James; Bliss, David E.; Campbell, Edward Michael; Gomez, Matthew R.; Harding, Eric; Harvey-Thompson, Adam James; Hansen, Stephanie B.; Jennings, Christopher Ashley; Kimmel, Mark W.; Knapp, Patrick; Lewis, Sean M.; McBride, Ryan D.; Peterson, Kyle; Schollmeier, Marius; Scoglietti, Daniel; Sefkow, Adam B.; Shores, Jonathon; Sinars, Daniel; Slutz, Stephen A.; Smith, Ian C.; Speas, Christopher; Vesey, Roger A.; Porter, John L.

    2016-03-04

    Sandia National Laboratories is pursuing a variation of Magneto-Inertial Fusion called Magnetized Liner Inertial Fusion, or MagLIF. The MagLIF approach requires magnetization of the deuterium fuel, which is accomplished by an initial external B-Field and laser-driven pre-heat. Although magnetization is crucial to the concept, it is challenging to couple sufficient energy to the fuel, since laser-plasma instabilities exist, and a compromise between laser spot size, laser entrance window thickness, and fuel density must be found. Ultimately, nonlinear processes in laser plasma interaction, or laser-plasma instabilities (LPI), complicate the deposition of laser energy by enhanced absorption, backscatter, filamentation and beam-spray. We determine and discuss key LPI processes and mitigation methods. Results with and without improvement measures are presented.

  10. Validation of a Numerical Method for Determining Liner Impedance

    NASA Technical Reports Server (NTRS)

    Watson, Willie R.; Jones, Michael G.; Tanner, Sharon E.; Parrott, Tony L.

    1996-01-01

    This paper reports the initial results of a test series to evaluate a method for determining the normal incidence impedance of a locally reacting acoustically absorbing liner, located on the lower wall of a duct in a grazing incidence, multi-modal, non-progressive acoustic wave environment without flow. This initial evaluation is accomplished by testing the methods' ability to converge to the known normal incidence impedance of a solid steel plate, and to the normal incidence impedance of an absorbing test specimen whose impedance was measured in a conventional normal incidence tube. The method is shown to converge to the normal incident impedance values and thus to be an adequate tool for determining the impedance of specimens in a grazing incidence, multi-modal, nonprogressive acoustic wave environment for a broad range of source frequencies.

  11. Aging of steel containments and liners in nuclear power plants

    SciTech Connect

    Naus, D.J.; Oland, C.B.; Ellingwood, B.; Norris, W.E.

    1998-01-01

    Aging of the containment pressure boundary in light water reactor plants is being addressed to understand the significant factors relating occurrence of corrosion efficacy of inspection and structural capacity reduction of steel containments and liners of concrete containments. and to make recommendations on use of risk models in regulatory decisions. Current regulatory in-service inspection requirements are reviewed and a summary of containment related degradation experience is presented. Current and emerging nondestructive examination techniques and a degradation assessment methodology for characterizing and quantifying the amount of damage present are described. Quantitative tools for condition assessment of aging structures using time dependent structural reliability analysis methods are summarized. Such methods provide a framework for addressing the uncertainties attendant to aging in the decision process. Results of this research provide a means for establishing current and estimating future structural capacity margins of containments, and to address the significance of incidences of reported containment degradation.

  12. Nonlinear Laser-Plasma Interaction in Magnetized Liner Inertial Fusion

    DOE PAGES

    Geissel, Matthias; Awe, Thomas James; Bliss, David E.; ...

    2016-03-04

    Sandia National Laboratories is pursuing a variation of Magneto-Inertial Fusion called Magnetized Liner Inertial Fusion, or MagLIF. The MagLIF approach requires magnetization of the deuterium fuel, which is accomplished by an initial external B-Field and laser-driven pre-heat. Although magnetization is crucial to the concept, it is challenging to couple sufficient energy to the fuel, since laser-plasma instabilities exist, and a compromise between laser spot size, laser entrance window thickness, and fuel density must be found. Ultimately, nonlinear processes in laser plasma interaction, or laser-plasma instabilities (LPI), complicate the deposition of laser energy by enhanced absorption, backscatter, filamentation and beam-spray. Wemore » determine and discuss key LPI processes and mitigation methods. Results with and without improvement measures are presented.« less

  13. Liner shape and power consumption in rotary mills

    SciTech Connect

    Valderrama, W.; Grandela, P.; Magne, L.

    1995-12-31

    The effect of liner shape on power consumption was studied in a small laboratory mill under various operating conditions. It was found that the angle subtended between the lifter front face and the face in contact with the mill case has the most significant influence. The increasing height of lifter reduced power consumption, whereas the lifter spacing did not show any influence. The effect of height is less relevant at lower front angles. Highest power consumption is achieved with a 450 front angle. A comparison of cylinders and balls under identical conditions gives higher power consumption for ball charges. The data does suggest that, for maximum power draw, slip in the outer layers of the charge and the early recirculation of energy to the mill case should be avoided. Both factors prevent an efficient energy transfer to the mill charge.

  14. Electrical leak detection system for landfill liners: A case history

    SciTech Connect

    White, C.C.; Barker, R.D.

    1997-12-01

    As landfill specifications become more stringent in the United Kingdom, the development of increasingly sophisticated monitoring methods is necessary to meet environmental protection goals. The case history describes the development of a 2-million-cubic-meter-capacity landfill, located in a sandstone quarry and 1 km from a public water supply borehole, where the sensitivity of the site to ground water contamination and the proximity to a public water supply borehole are particular issues. The landfill design incorporated a more sensitive environmental monitoring system, using a geophysical technique. The monitoring system comprises a permanent grid of electrodes installed beneath the landfill, connected by multicore cable to a computer-controlled earth resistance meter and switching unit in the site weighbridge. It was designed to detect holes in the landfill liner prior to and after covering with waste and to monitor the migration of contaminants beneath the landfill before they reach the perimeter observation boreholes, should leakage occur.

  15. Affinity of titanium dioxide nanoparticles for sodium montmorillonite clay: Implications for disposal in municipal solid waste landfills

    NASA Astrophysics Data System (ADS)

    Harns, Carrie

    Manufactured nanomaterials are used in a diverse array of commercially available products. Like other consumer goods, a portion of manufactured nano-products will enter municipal solid waste (MSW) landfills. Currently there is little information on the behavior and fate of engineered nanomaterials in MSW landfills and thus we do not know if current landfill designs are suitable for engineered nanomaterials. Of great consequence is understanding how nanomaterials will interact with clays, as they are integral components of composite liner systems. The overall objectives were to determine the affinity of titanium dioxide (TiO2) nanomaterials for montmorillonite as a function of solution chemistry and evaluate the mobility of TiO2 nanomaterials across clay barriers. It was observed that under favorable electrostatic conditions, TiO2 will heteroaggregate with montmorillonite, and TiO2-montmorillonite suspensions will remain stable under unfavorable electrostatic conditions. Additionally, it was observed that under simplified landfill leachate conditions, the clay barrier retained TiO2.

  16. Comparison of Acoustic Impedance Eduction Techniques for Locally-Reacting Liners

    NASA Technical Reports Server (NTRS)

    Jones, M. G.; Parrott, T. L.; Watson, W. R.

    2003-01-01

    Typical acoustic liners used in current aircraft inlets and aft-fan ducts consist of some type of perforated facesheet bonded to a honeycomb core. A number of techniques for determining the acoustic impedance of these locallyreacting liners have been developed over the last five decades. In addition, a number of models have been developed to predict the acoustic impedance of locallyreacting liners in the presence of grazing flow, and to use that information together with aeroacoustic propagation codes to assess the noise absorption provided by these liners. These prediction models have incorporated the results from databases acquired with specific impedance eduction techniques. Thus, while these prediction models are acceptable for liners that are similar to those tested in these databases, their application to new liner configurations must be viewed with caution. The primary purpose of this paper is to provide a comparison of impedance eduction techniques that have been implemented at various aerospace research laboratories in the United States (NASA Langley Research Center, General Electric Aircraft Engines, B. F. Goodrich and Boeing). A secondary purpose is to provide data for liner configurations that extend the porosity range beyond that which has been previously used in common aircraft engine nacelles. Two sets of liners were designed to study the effects of three parameters: perforate hole diameter, facesheet thickness and porosity. These two sets of liners were constructed for testing in each of the laboratories listed above. The first set of liners was designed to fit into the NASA Langley and Boeing test facilities. The second set was designed to fit into the General Electric Aircraft Engines and B. F. Goodrich test facilities. By using the same parent material, both sets of liners were identical to within the limits of material and fabrication variability. Baseline data were obtained in the normal incidence impedance tubes at NASA Langley and B. F

  17. Method and apparatus for monitoring the integrity of a geomembrane liner using time domain reflectometry

    DOEpatents

    Morrison, John L.

    2001-04-24

    Leaks are detected in a multi-layered geomembrane liner by a two-dimensional time domain reflectometry (TDR) technique. The TDR geomembrane liner is constructed with an electrically conductive detection layer positioned between two electrically non-conductive dielectric layers, which are each positioned between the detection layer and an electrically conductive reference layer. The integrity of the TDR geomembrane liner is determined by generating electrical pulses within the detection layer and measuring the time delay for any reflected electrical energy caused by absorption of moisture by a dielectric layer.

  18. Filament wound pressure vessels with load sharing liners for Space Shuttle Orbiter applications

    NASA Technical Reports Server (NTRS)

    Ecord, G. M.

    1976-01-01

    It is recognized that the use of overwrapped pressure vessels with load sharing liners may provide significant weight savings for high pressure gas containment in Space Shuttle Orbiter systems. The technology readiness to produce Kevlar wound vessels with load sharing liners of titanium 6Al-4V, Inconel 718 or cryoformed 301 steel has been demonstrated. It has been estimated that about 400 lbs can be saved in the Orbiter by using overwrapped vessels with load sharing liners instead of monolithic metal designs. Total weight of the composite vessels would be about 1350 lbs as opposed to about 1750 lbs for all-metal vessels.

  19. Method and Apparatus for Monitoring the Integrity of a Geomembrane Liner using time Domain Reflectometry

    SciTech Connect

    Morris, John L.

    1998-11-09

    Leaks are detected in a multi-layered geomembrane liner by a two-dimensional time domain reflectometry (TDR) technique. The TDR geomembrane liner is constructed with an electrically conductive detection layer positioned between two electrically non-conductive dielectric layers, which are each positioned between the detection layer and an electrically conductive reference layer. The integrity of the TDR geomembrane liner is determined by generating electrical pulses within the detection layer and measuring the time delay for any reflected electrical energy caused by absorption of moisture by a dielectric layer.

  20. 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.

  1. Photochemistry on, and Nature of Adsorbed Species on Colloidal Clay and Model Clay Systems.

    DTIC Science & Technology

    1987-09-25

    model system for clays, and also acts as a bridge between ionic organic micelle systems and colloidal clays. In the first instance a commercial...hexadecylpyridinium chloride, tend to cluster on the silica surface rather than disperse uniformly around it as with ionic micelles. We have also...alcohol as additives to the clay. Layers of organic material are formed by these additives in montmorillonite layers, and now non- ionic organic

  2. The Basics in Pottery: Clay and Tools.

    ERIC Educational Resources Information Center

    Larson, Joan

    1985-01-01

    Art teachers at the middle school or junior high school level usually find themselves in a program teaching ceramics. The most essential tools needed for a ceramics class are discussed. Different kinds of clay are also discussed. (RM)

  3. Natural Radioactivity of Boron Added Clay Samples

    SciTech Connect

    Akkurt, I.; Guenoglu, K.; Canakcii, H.; Mavi, B.

    2011-12-26

    Clay, consisting fine-grained minerals, is an interesting materials and can be used in a variety of different fields especially in dermatology application. Using clay such a field it is important to measure its natural radioactivity. Thus the purpose of this study is to measure {sup 226}Ra, {sup 232}Th and {sup 40}K concentration in clay samples enriched with boron. Three different types of clay samples were prepared where boron is used in different rate. The measurements have been determined using a gamma-ray spectrometry consists of a 3''x3'' NaI(Tl) detector. From the measured activity the radium equivalent activities (Ra{sub eq}), external hazard index (H{sub ex}), absorbed dose rate in air (D) and annual effective dose (AED) have also been obtained.

  4. Natural Radioactivity of Boron Added Clay Samples

    NASA Astrophysics Data System (ADS)

    Akkurt, I.; ćanakciı, H.; Mavi, B.; Günoǧlu, K.

    2011-12-01

    Clay, consisting fine-grained minerals, is an interesting materials and can be used in a variety of diferent fields especially in dermatology application. Using clay such a field it is important to measure its natural radioacitivty. Thus the purpose of this study is to measure 226Ra, 232Th and 40K concentration in clay samples enriched with boron. Three different types of clay samples were prepared where boron is used in different rate. The measurements have been determined using a gamma-ray spectrometry consists of a 3″×3″ NaI(Tl) detector. From the measured activity the radium equivalent activities (Raeq), external hazard index (Hex), absorbed dose rate in air (D) and annual effective dose (AED) have also been obtained.

  5. Clay-Bacteria Systems and Biofilm Production

    NASA Astrophysics Data System (ADS)

    Steiner, J.; Alimova, A.; Katz, A.; Steiner, N.; Rudolph, E.; Gottlieb, P.

    2007-12-01

    Soil clots and the aerosol transport of bacteria and spores are promoted by the formation of biofilms (bacteria cells in an extracellular polymeric matrix). Biofilms protect microorganisms by promoting adhesion to both organic and inorganic surfaces. Time series experiments on bacteria-clay suspensions demonstrate that biofilm growth is catalyzed by the presence of hectorite in minimal growth media for the studied species: Gram negatives (Pseudomonas syringae and Escherichia coli,) and Gram positives (Staphylococcus aureus and Bacillus subtilis). Soil organisms (P. syringae, B. subtilis) and organisms found in the human population (E. coli, S. aureus) are both used to demonstrate the general applicability of clay involvement. Fluorescent images of the biofilms are acquired by staining with propidium iodide, a component of the BacLightTM Live/Dead bacterial viability staining kit (Molecular Probes, Eugene, OR). The evolving polysaccharide-rich biofilm reacts with the clay interlayer site causing a complex substitution of the two-water hectorite interlayer with polysaccharide. The result is often a three-peak composite of the (001) x-ray diffraction maxima resulting from polysaccharide-expanded clays and an organic-driven contraction of a subset of the clays in the reaction medium. X-ray diffractograms reveal that the expanded set creates a broad maximum with clay subsets at 1.84 nm and 1.41 nm interlayer spacings as approximated by a least squares double Lorentzian fit, and a smaller shoulder at larger 2q, deriving from a contraction of the interlayer spacing. Washing with chlorox removes organic material from the contracted clay and creates a 1-water hectorite single peak in place of the double peak. The clay response can be used as an indirect indicator of biofilm in an environmental system.

  6. Cobalt sorption in silica-pillared clays.

    PubMed

    Sampieri, A; Fetter, G; Bosch, P; Bulbulian, S

    2006-01-03

    Silicon pillared samples were prepared following conventional and microwave irradiation methods. The samples were characterized and tested in cobalt sorption. Ethylenediammine was added before cobalt addition to improve the amount of cobalt retained. The amount of cobalt introduced in the original clay in the presence of ethylenediammine was the highest. In calcined pillared clays the cobalt retention with ethylenediammine was lower (ca. 40%). In all cases the presence of ethylenediammine increased twice the amount of cobalt sorption measured for aqueous solutions.

  7. Clay-mediated reactions of HCN oligomers - The effect of the oxidation state of the clay

    NASA Technical Reports Server (NTRS)

    Ferris, J. P.; Alwis, K. W.; Edelson, E. H.; Mount, N.; Hagan, W. J., Jr.

    1981-01-01

    Montmorillonite clays which contain Fe(III) inhibit the oligomerization of aqueous solutions of HCN. The inhibitory effect is due to the rapid oxidation of diaminomaleonitrile, a key intermediate in HCN oligomerization, by the Fe(III) incorporated into the aluminosilicate lattice of the clay. The Fe(III) oxidizes diaminomaleonitrile to diiminosuccinonitrile, a compound which is rapidly hydrolyzed to HCN and oxalic acid derivatives. Diaminomaleonitrile is not oxidized when Fe(III) in the montmorillonite is reduced with hydrazine. The oxidation state of the clay is an important variable in experiments designed to simulate clay catalysis on the primitive earth.

  8. What Makes a Natural Clay Antibacterial?

    PubMed Central

    Williams, Lynda B.; Metge, David W.; Eberl, Dennis D.; Harvey, Ronald W.; Turner, Amanda G.; Prapaipong, Panjai; Poret-Peterson, Amisha T.

    2011-01-01

    Natural clays have been used in ancient and modern medicine, but the mechanism(s) that make certain clays lethal against bacterial pathogens has not been identified. We have compared the depositional environments, mineralogies, and chemistries of clays that exhibit antibacterial effects on a broad spectrum of human pathogens including antibiotic resistant strains. Natural antibacterial clays contain nanoscale (<200 nm), illite-smectite and reduced iron phases. The role of clay minerals in the bactericidal process is to buffer the aqueous pH and oxidation state to conditions that promote Fe2+ solubility. Chemical analyses of E. coli killed by aqueous leachates of an antibacterial clay show that intracellular concentrations of Fe and P are elevated relative to controls. Phosphorus uptake by the cells supports a regulatory role of polyphosphate or phospholipids in controlling Fe2+. Fenton reaction products can degrade critical cell components, but we deduce that extracellular processes do not cause cell death. Rather, Fe2+ overwhelms outer membrane regulatory proteins and is oxidized when it enters the cell, precipitating Fe3+ and producing lethal hydroxyl radicals. PMID:21413758

  9. Soil clay content underlies prion infection odds

    USGS Publications Warehouse

    David, Walter W.; Walsh, D.P.; Farnsworth, Matthew L.; Winkelman, D.L.; Miller, M.W.

    2011-01-01

    Environmental factors-especially soil properties-have been suggested as potentially important in the transmission of infectious prion diseases. Because binding to montmorillonite (an aluminosilicate clay mineral) or clay-enriched soils had been shown to enhance experimental prion transmissibility, we hypothesized that prion transmission among mule deer might also be enhanced in ranges with relatively high soil clay content. In this study, we report apparent influences of soil clay content on the odds of prion infection in free-ranging deer. Analysis of data from prion-infected deer herds in northern Colorado, USA, revealed that a 1% increase in the clay-sized particle content in soils within the approximate home range of an individual deer increased its odds of infection by up to 8.9%. Our findings suggest that soil clay content and related environmental properties deserve greater attention in assessing risks of prion disease outbreaks and prospects for their control in both natural and production settings. ?? 2011 Macmillan Publishers Limited. All rights reserved.

  10. Pier-scour depths affected by clay in Mississippi

    USGS Publications Warehouse

    Wilson, K. Van

    1998-01-01

    This paper briefly presents pier-scour depths measured during 1943-94, that are thought to have been affected by consolidated cohesive materials (clay) in Mississippi. MDOT soil reports were available for 29 measured pier-scour depths thought to be affected by clay. The cohesion and friction angles were approximated for the clay, and using the soil borings where clay was overlain by sand and(or) gravel, the top of the clay stratum was approximated in order to determine the net scour through the clay. Eight additional measured pier-scour depths were thought to be affected by clay, but no MDOT soil reports or borings were available. The net pier-scour depth through the clay is a rough approximation where sand and (or) gravel overlie a clay stratum and, therefore, only represents part of the total pier-scour depth. Limited data indicate the pier-scour depth decreases as shear strength of the clay increases.

  11. The design and flight test of an engine inlet bulk acoustic liner

    NASA Technical Reports Server (NTRS)

    Lester, H. C.; Preisser, J. S.; Parrott, T. L.

    1983-01-01

    This paper summarizes the design, fabrication and flight evaluation of a Kevlar acoustic liner configuration for a JT15D turbofan engine. The liner was designed to suppress, by a measurable amount, a dominant (13,0) BPF tone. This tone or spinning mode was produced for research purposes by installing 41 circumferentially distributed small diameter rods upstream of the 28 fan blades. Duct liner attenuations calculated by a finite element procedure were compared to far field power (insertion) losses deduced from flight data. The finite element program modeled the variable geometry of the JT15D inlet and used a uniform flow with a boundary layer roll-off to model the inlet flow field. Calculated liner losses were generally conservative. That is, measured far field power losses were generally greater than attenuations calculated by the finite element computer program.

  12. Formation of metal and dielectric liners using a solution process for deep trench capacitors.

    PubMed

    Ham, Yong-Hyun; Kim, Dong-Pyo; Baek, Kyu-Ha; Park, Kun-Sik; Kim, Moonkeun; Kwon, Kwang-Ho; Shin, Hong-Sik; Lee, Kijun; Do, Lee-Mi

    2012-07-01

    We demonstrated the feasibility of metal and dielectric liners using a solution process for deep trench capacitor application. The deep Si trench via with size of 10.3 microm and depth of 71 microm were fabricated by Bosch process in deep reactive ion etch (DRIE) system. The aspect ratio was about 7. Then, nano-Ag ink and poly(4-vinylphenol) (PVPh) were used to form metal and dielectric liners, respectively. The thicknesses of the Ag and PVPh liners were about 144 and 830 nm, respectively. When the curing temperature of Ag film increased from 120 to 150 degrees C, the sheet resistance decreased rapidly from 2.47 to 0.72 Omega/sq and then slightly decreased to 0.6 Omega/sq with further increasing the curing temperature beyond 150 degrees C. The proposed liner formation method using solution process is a simple and cost effective process for the high capacity of deep trench capacitor.

  13. 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.

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

    NASA Astrophysics Data System (ADS)

    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.

    2016-02-01

    Enhanced implosion stability has been experimentally demonstrated for magnetically accelerated liners that are coated with 70 μ m 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 μ m over the 4.0 mm axial height captured by the radiograph.

  15. Duct liner optimization for turbomachinery noise sources. [aircraft noise/engine noise - numerical analysis

    NASA Technical Reports Server (NTRS)

    Lester, H. C.; Posey, J. W.

    1975-01-01

    An acoustical field theory for axisymmetric, multisectioned lined ducts with uniform flow profiles was combined with a numerical minimization algorithm to predict optimal liner configurations having one, two, and three sections. Source models studied include a point source located on the axis of the duct and rotor/outlet-stator viscous wake interaction effects for a typical research compressor operating at an axial flow Mach number of about 0.4. For this latter source, optimal liners for equipartition-of energy, zero-phase, and least-attenuated-mode source variations were also calculated and compared with exact results. It is found that the potential benefits of liner segmentation for the attenuation of turbomachinery noise is greater than would be predicted from point source results. Furthermore, effective liner design requires precise knowledge of the circumferential and radial modal distributions.

  16. Evaluation of two polyimides and of an improved liner retention design for self-lubricating bushings

    NASA Technical Reports Server (NTRS)

    Sliney, H. E.

    1984-01-01

    Two different polyimide polymers were studied and the effectiveness of a design feature to improve retention of the self lubricating composite liners under high load was evaluated. The basic bearing design consisted of a molded layer of chopped graphite-fiber-reinforced-polyimide (GFRP) composite bonded to the bore of a steel bushing. The friction, wear, and load carrying ability of the bushings were determined in oscillating tests at 25, 260 and 315 C at radial unit loads up to 260 MPa. Friction coefficients were typically 0.15 to 0.25. Bushings with liners containing a new partially fluorinated polymer were functional, but had a lower load capacity and higher wear rate than those containing a more conventional, high temperature polyimide. The liner retention design feature reduced the tendency of the liners to crack and work out of the contact zone under high oscillating loads.

  17. ETV Program Report: Coatings for Wastewater Collection Systems - Protective Liner Systems, Inc., Epoxy Mastic, PLS-614

    EPA Science Inventory

    The Protective Liner Systems International, Inc. Epoxy Mastic PLS-614 coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Material and T...

  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.; ...

    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. Adaptive Back Sheet Material for Acoustic Liner Applications-ARMD Seedling Fund Phase I Final Report

    NASA Technical Reports Server (NTRS)

    Gerhold, Carl H.; Jones, Michael G.; Farrar, Dawnielle

    2014-01-01

    A recently developed piezo-electric composite film is evaluated for its usefulness in application in acoustic liners. Researchers at the NASA Langley Research Center Liner Technology Facility developed experiments to measure the electrical response of the material to acoustic excitation and the vibrational response of the material to electrical excitation. The robustness of the piezo-electric film was also assessed. The material's electrical response to acoustic excitation is found to be comparable to a commercial microphone in the range of frequencies from 500 to 3000 Hz. However, the vibrational response to electrical excitation in the frequency range of interest is an order of magnitude less than may be necessary for application to acoustic liners. Nevertheless, experimental results indicate that the potential exists for the material to produce a measurable change in the impedance spectrum of a liner. Work continues to improve the authority of the piezo-electric film.

  20. On the attenuation of sound by three-dimensionally segmented acoustic liners in a rectangular duct

    NASA Technical Reports Server (NTRS)

    Koch, W.

    1979-01-01

    Axial segmentation of acoustically absorbing liners in rectangular, circular or annual duct configurations is a very useful concept for obtaining higher noise attenuation with respect to the bandwidth of absorption as well as the maximum attenuation. As a consequence, advanced liner concepts are proposed which induce a modal energy transfer in both cross-sectional directions to further reduce the noise radiated from turbofan engines. However, these advanced liner concepts require three-dimensional geometries which are difficult to treat theoretically. A very simple three-dimensional problem is investigated analytically. The results show a strong dependence on the positioning of the liner for some incident source modes while the effect of three-dimensional segmentation appears to be negligible over the frequency range considered.