Science.gov

Sample records for additional supporting materials

  1. Navy Additive Manufacturing: Policy Analysis for Future DLA Material Support

    DTIC Science & Technology

    2014-12-01

    support programs. 14. SUBJECT TERMS additive manufacturing, 3D printing, technology adoption 15. NUMBER OF PAGES 69 16...LEFT BLANK xii LIST OF ACRONYMS AND ABBREVIATIONS 3D Three Dimensions or Three Dimensional 3DP 3D Printing AM Additive Manufacturing AMDO...this is about to change. Additive manufacturing (AM) systems (commonly known as “ 3D printing”) could bring the organic parts manufacturing capability

  2. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  3. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  4. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  5. 46 CFR 355.5 - Additional material.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Additional material. 355.5 Section 355.5 Shipping... STATES CITIZENSHIP § 355.5 Additional material. If additional material is determined to be essential to clarify or support the evidence of U.S. citizenship, such material shall be furnished by...

  6. ATS materials support

    SciTech Connect

    Karnitz, M.A.; Wright, I.G.; Ferber, M.K.; Holcomb, R.S.; Rawlins, M.H.

    1996-12-31

    The technology based portion of the Advanced Turbine System Program (ATS) contains several subelements which address generic technology issues for land-base gas turbine systems. One subelement is the Materials/Manufacturing Technology Program which is coordinated by DOE-Oak Ridge Operations and Oak Ridge National laboratory (ORNL) for the Department of Energy. The work in this subelement is being performed predominantly by industry with assistance from national laboratories and universities. Projects in this subelement are aimed toward hastening the incorporation of new materials and components in gas turbines. The materials manufacturing subelement was developed with input from gas turbine manufacturers, material suppliers, government laboratories and universities. Work is currently ongoing on thermal barrier coatings (TBCs), the scale-up of single-crystal airfoil manufacturing technologies, materials characterization and technology information exchange. Westinghouse Power Generation and Pratt and Whitney each have material programs to develop dependable TBCs that enable increased turbine inlet temperatures while maintaining airfoil substrate temperatures at levels to meet the ATS life goals. Howmet and PCC Airfoils each have projects to extend the capability of single-crystal complex-cored airfoil technology to larger sizes so that higher turbine inlet temperatures can be attained in land-based turbines in a cost-effective manner. Materials characterization tasks are ongoing on TBCs in support of the industrial projects. In addition, a project on long-term testing of ceramics and ceramic-matrix composites for gas turbines is being conducted in support of programs at Solar Turbines, Allison Engines, and Westinghouse Power Generation.

  7. Materials support for HITAF

    SciTech Connect

    Breder, K.; Tennery, V.J.

    1994-09-01

    The primary objective of this work is to compare the mechanical performance of structural ceramic materials which are being proposed for use in the air heater of a coal fired high temperature advanced furnace (HITAF) for power generation. The effort is focused on providing preliminary evaluations of key mechanical properties required of ceramic materials for this application. The critical properties studied include fast fracture strength distribution at room temperature and two elevated temperatures, any trends in slow crack growth (SCG) susceptibility at elevated temperatures, and preliminary creep behavior. In addition residual fast fracture strength of a limited number of specimens corroded in a coal ash environment will be evaluated at a later stage in the project.

  8. Materials support for HITAF

    SciTech Connect

    Breder, K.; Parten, R.J.; Lin, H.T.

    1996-06-01

    The purpose of this project is to compare structural ceramic materials proposed for use in the air heater of a coal fired high temperature furnace (HITAF) for power generation. This new generation of coal fired power plants with increased efficiency, fewer emissions and lower costs are currently being developed under the Combustion 2000 program funded by Pittsburgh Energy Technology Center (PETC). Large improvements in efficiencies will require a change to combined cycles that employ gas turbines and steam turbines (Brayton Cycle) instead of exclusive reliance on steam turbines. Extremely high temperature working fluid is required to boost the efficiency, and the result is that the power plant sub-systems will be exposed to much more corrosive environments than in the present systems. The uses of ceramic heat exchangers are being investigated for those new power plants because of the potential for producing a clean, hot working fluid for the gas turbine.

  9. Materials as additives for advanced lubrication

    DOEpatents

    Pol, Vilas G.; Thackeray, Michael M.; Mistry, Kuldeep; Erdemir, Ali

    2016-09-13

    This invention relates to carbon-based materials as anti-friction and anti-wear additives for advanced lubrication purposes. The materials comprise carbon nanotubes suspended in a liquid hydrocarbon carrier. Optionally, the compositions further comprise a surfactant (e.g., to aid in dispersion of the carbon particles). Specifically, the novel lubricants have the ability to significantly lower friction and wear, which translates into improved fuel economies and longer durability of mechanical devices and engines.

  10. Radioprotective materials with tungsten nanopowder additives

    NASA Astrophysics Data System (ADS)

    Gavrish, V.; Baranov, G.; Chayka, T.; Derbasova, N.

    2017-01-01

    There’s been studied influence of submicron powder additives obtained by processing hardmetal waste TTK (TiC-WC-TaC-Co), on strength properties of cement. This modified cement is used as a structural material for containers at transportation and storage of radioactive waste.

  11. Additive manufacturing of materials: Opportunities and challenges

    SciTech Connect

    Babu, Sudarsanam Suresh; Love, Lonnie J.; Dehoff, Ryan R.; Peter, William H.; Watkins, Thomas R.; Pannala, Sreekanth

    2015-11-01

    Additive manufacturing (also known as 3D printing) is considered a disruptive technology for producing components with topologically optimized complex geometries as well as functionalities that are not achievable by traditional methods. The realization of the full potential of 3D printing is stifled by a lack of computational design tools, generic material feedstocks, techniques for monitoring thermomechanical processes under in situ conditions, and especially methods for minimizing anisotropic static and dynamic properties brought about by microstructural heterogeneity. In this paper, we discuss the role of interdisciplinary research involving robotics and automation, process control, multiscale characterization of microstructure and properties, and high-performance computational tools to address each of these challenges. In addition, emerging pathways to scale up additive manufacturing of structural materials to large sizes (>1 m) and higher productivities (5–20 kg/h) while maintaining mechanical performance and geometrical flexibility are also discussed.

  12. Additive manufacturing of materials: Opportunities and challenges

    DOE PAGES

    Babu, Sudarsanam Suresh; Love, Lonnie J.; Dehoff, Ryan R.; ...

    2015-11-01

    Additive manufacturing (also known as 3D printing) is considered a disruptive technology for producing components with topologically optimized complex geometries as well as functionalities that are not achievable by traditional methods. The realization of the full potential of 3D printing is stifled by a lack of computational design tools, generic material feedstocks, techniques for monitoring thermomechanical processes under in situ conditions, and especially methods for minimizing anisotropic static and dynamic properties brought about by microstructural heterogeneity. In this paper, we discuss the role of interdisciplinary research involving robotics and automation, process control, multiscale characterization of microstructure and properties, and high-performancemore » computational tools to address each of these challenges. In addition, emerging pathways to scale up additive manufacturing of structural materials to large sizes (>1 m) and higher productivities (5–20 kg/h) while maintaining mechanical performance and geometrical flexibility are also discussed.« less

  13. Additive manufacturing of biologically-inspired materials.

    PubMed

    Studart, André R

    2016-01-21

    Additive manufacturing (AM) technologies offer an attractive pathway towards the fabrication of functional materials featuring complex heterogeneous architectures inspired by biological systems. In this paper, recent research on the use of AM approaches to program the local chemical composition, structure and properties of biologically-inspired materials is reviewed. A variety of structural motifs found in biological composites have been successfully emulated in synthetic systems using inkjet-based, direct-writing, stereolithography and slip casting technologies. The replication in synthetic systems of design principles underlying such structural motifs has enabled the fabrication of lightweight cellular materials, strong and tough composites, soft robots and autonomously shaping structures with unprecedented properties and functionalities. Pushing the current limits of AM technologies in future research should bring us closer to the manufacturing capabilities of living organisms, opening the way for the digital fabrication of advanced materials with superior performance, lower environmental impact and new functionalities.

  14. Computed tomography characterisation of additive manufacturing materials.

    PubMed

    Bibb, Richard; Thompson, Darren; Winder, John

    2011-06-01

    Additive manufacturing, covering processes frequently referred to as rapid prototyping and rapid manufacturing, provides new opportunities in the manufacture of highly complex and custom-fitting medical devices and products. Whilst many medical applications of AM have been explored and physical properties of the resulting parts have been studied, the characterisation of AM materials in computed tomography has not been explored. The aim of this study was to determine the CT number of commonly used AM materials. There are many potential applications of the information resulting from this study in the design and manufacture of wearable medical devices, implants, prostheses and medical imaging test phantoms. A selection of 19 AM material samples were CT scanned and the resultant images analysed to ascertain the materials' CT number and appearance in the images. It was found that some AM materials have CT numbers very similar to human tissues, FDM, SLA and SLS produce samples that appear uniform on CT images and that 3D printed materials show a variation in internal structure.

  15. Microstructural Control of Additively Manufactured Metallic Materials

    NASA Astrophysics Data System (ADS)

    Collins, P. C.; Brice, D. A.; Samimi, P.; Ghamarian, I.; Fraser, H. L.

    2016-07-01

    In additively manufactured (AM) metallic materials, the fundamental interrelationships that exist between composition, processing, and microstructure govern these materials’ properties and potential improvements or reductions in performance. For example, by using AM, it is possible to achieve highly desirable microstructural features (e.g., highly refined precipitates) that could not otherwise be achieved by using conventional approaches. Simultaneously, opportunities exist to manage macro-level microstructural characteristics such as residual stress, porosity, and texture, the last of which might be desirable. To predictably realize optimal microstructures, it is necessary to establish a framework that integrates processing variables, alloy composition, and the resulting microstructure. Although such a framework is largely lacking for AM metallic materials, the basic scientific components of the framework exist in literature. This review considers these key components and presents them in a manner that highlights key interdependencies that would form an integrated framework to engineer microstructures using AM.

  16. Infrared Database for Process Support Materials

    NASA Technical Reports Server (NTRS)

    Bennett, K. E.; Boothe, R. E.; Burns, H. D.

    2003-01-01

    Process support materials' compatibility with cleaning processes is critical to ensure final hardware cleanliness and that performance requirements are met. Previous discovery of potential contaminants in process materials shows the need for incoming materials testing and establishment of a process materials database. The Contamination Control Team of the Materials, Processes, and Manufacturing (MP&M) Department at Marshall Space Flight Center (MSFC) has initiated the development of such an infrared (IR) database, called the MSFC Process Materials IR database, of the common process support materials used at MSFC. These process support materials include solvents, wiper cloths, gloves, bagging materials, etc. Testing includes evaluation of the potential of gloves, wiper cloths, and other items to transfer contamination to handled articles in the absence of solvent exposure, and the potential for solvent exposure to induce material degradation. This Technical Memorandum (TM) summarizes the initial testing completed through December 2002. It is anticipated that additional testing will be conducted with updates provided in future TMs.Materials were analyzed using two different IR techniques: (1) Dry transference and (2) liquid extraction testing. The first of these techniques utilized the Nicolet Magna 750 IR spectrometer outfitted with a horizontal attenuated total reflectance (HATR) crystal accessory. The region from 650 to 4,000 wave numbers was analyzed, and 50 scans were performed per IR spectrum. A dry transference test was conducted by applying each sample with hand pressure to the HATR crystal to first obtain a spectrum of the parent material. The material was then removed from the HATR crystal and analyzed to determine the presence of any residues. If volatile, liquid samples were examined both prior to and following evaporation.The second technique was to perform an extraction test with each sample in five different solvents.Once the scans were complete for

  17. Laser Additive Manufacturing of Magnetic Materials

    NASA Astrophysics Data System (ADS)

    Mikler, C. V.; Chaudhary, V.; Borkar, T.; Soni, V.; Jaeger, D.; Chen, X.; Contieri, R.; Ramanujan, R. V.; Banerjee, R.

    2017-03-01

    While laser additive manufacturing is becoming increasingly important in the context of next-generation manufacturing technologies, most current research efforts focus on optimizing process parameters for the processing of mature alloys for structural applications (primarily stainless steels, titanium base, and nickel base alloys) from pre-alloyed powder feedstocks to achieve properties superior to conventionally processed counterparts. However, laser additive manufacturing or processing can also be applied to functional materials. This article focuses on the use of directed energy deposition-based additive manufacturing technologies, such as the laser engineered net shaping (LENS™) process, to deposit magnetic alloys. Three case studies are presented: Fe-30 at.%Ni, permalloys of the type Ni-Fe-V and Ni-Fe-Mo, and Fe-Si-B-Cu-Nb (derived from Finemet) alloys. All these alloys have been processed from a blend of elemental powders used as the feedstock, and their resultant microstructures, phase formation, and magnetic properties are discussed in this paper. Although these alloys were produced from a blend of elemental powders, they exhibited relatively uniform microstructures and comparable magnetic properties to those of their conventionally processed counterparts.

  18. Electrostatic Levitation for Studies of Additive Manufactured Materials

    NASA Technical Reports Server (NTRS)

    SanSoucie, Michael P.; Rogers, Jan R.; Tramel, Terri

    2014-01-01

    The electrostatic levitation (ESL) laboratory at NASA's Marshall Space Flight Center is a unique facility for investigators studying high temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified. Electrostatic levitation minimizes gravitational effects and allows materials to be studied without contact with a container or instrumentation. The lab also has a high temperature emissivity measurement system, which provides normal spectral and normal total emissivity measurements at use temperature. The ESL lab has been instrumental in many pioneering materials investigations of thermophysical properties, e.g., creep measurements, solidification, triggered nucleation, and emissivity at high temperatures. Research in the ESL lab has already led to the development of advanced high temperature materials for aerospace applications, coatings for rocket nozzles, improved medical and industrial optics, metallic glasses, ablatives for reentry vehicles, and materials with memory. Modeling of additive manufacturing materials processing is necessary for the study of their resulting materials properties. In addition, the modeling of the selective laser melting processes and its materials property predictions are also underway. Unfortunately, there is very little data for the properties of these materials, especially of the materials in the liquid state. Some method to measure thermophysical properties of additive manufacturing materials is necessary. The ESL lab is ideal for these studies. The lab can provide surface tension and viscosity of molten materials, density measurements, emissivity measurements, and even creep strength measurements. The ESL lab can also determine melting temperature, surface temperatures, and phase transition temperatures of additive manufactured materials. This presentation will provide background on the ESL lab and its capabilities, provide an approach to using the ESL

  19. Additively manufactured metallic pentamode meta-materials

    NASA Astrophysics Data System (ADS)

    Hedayati, R.; Leeflang, A. M.; Zadpoor, A. A.

    2017-02-01

    Mechanical metamaterials exhibit unusual mechanical properties that originate from their topological design. Pentamode metamaterials are particularly interesting because they could be designed to possess any thermodynamically admissible elasticity tensor. In this study, we additively manufacture the metallic pentamode metamaterials from a biocompatible and mechanically strong titanium alloy (Ti-6Al-4V) using an energy distribution method developed for the powder bed fusion techniques. The mechanical properties of the developed materials were a few orders of magnitude higher than those of the similar topologies fabricated previously from polymers. Moreover, the elastic modulus and yield stress of the presented pentamode metamaterials were decoupled from their relative density, meaning that the metallic meta-biomaterials with independently tailored elastic and mass transport (permeability) properties could be designed for tissue regeneration purposes.

  20. Additional Support Needs Policy in Scotland: Challenging or Reinforcing Social Inequality?

    ERIC Educational Resources Information Center

    Riddell, Sheila; Weedon, Elisabet

    2016-01-01

    This paper focuses on Scottish policy on additional support needs and its material outcomes. The central question addressed is the extent to which the Scottish additional support needs system undermines or reinforces existing social and economic inequalities. Administrative data highlight the inflation of the additional support needs category,…

  1. Dielectric breakdown of additively manufactured polymeric materials

    SciTech Connect

    Monzel, W. Jacob; Hoff, Brad W.; Maestas, Sabrina S.; French, David M.; Hayden, Steven C.

    2016-01-11

    Dielectric strength testing of selected Polyjet-printed polymer plastics was performed in accordance with ASTM D149. This dielectric strength data is compared to manufacturer-provided dielectric strength data for selected plastics printed using the stereolithography (SLA), fused deposition modeling (FDM), and selective laser sintering (SLS) methods. Tested Polyjet samples demonstrated dielectric strengths as high as 47.5 kV/mm for a 0.5 mm thick sample and 32.1 kV/mm for a 1.0 mm sample. As a result, the dielectric strength of the additively manufactured plastics evaluated as part of this study was lower than the majority of non-printed plastics by at least 15% (with the exception of polycarbonate).

  2. Dielectric breakdown of additively manufactured polymeric materials

    DOE PAGES

    Monzel, W. Jacob; Hoff, Brad W.; Maestas, Sabrina S.; ...

    2016-01-11

    Dielectric strength testing of selected Polyjet-printed polymer plastics was performed in accordance with ASTM D149. This dielectric strength data is compared to manufacturer-provided dielectric strength data for selected plastics printed using the stereolithography (SLA), fused deposition modeling (FDM), and selective laser sintering (SLS) methods. Tested Polyjet samples demonstrated dielectric strengths as high as 47.5 kV/mm for a 0.5 mm thick sample and 32.1 kV/mm for a 1.0 mm sample. As a result, the dielectric strength of the additively manufactured plastics evaluated as part of this study was lower than the majority of non-printed plastics by at least 15% (with themore » exception of polycarbonate).« less

  3. 9. DETAIL OF FIXED SUPPORT (A RECENT ADDITION THE ...

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

    9. DETAIL OF FIXED SUPPORT (A RECENT ADDITION -- THE BRIDGE IS NO LONGER MOVEABLE) AND LOWER CHORD OF THROUGH TRUSS, LOOKING SOUTH - Romeo Road, Sanitary & Ship Canal Bridge, Spanning Sanitary & Ship Canal, Romeoville, Will County, IL

  4. Computer Maintenance Operations Center (CMOC), additional computer support equipment ...

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

    Computer Maintenance Operations Center (CMOC), additional computer support equipment - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Techinical Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  5. Additional Support Needs Reforms and Social Justice in Scotland

    ERIC Educational Resources Information Center

    Riddell, Sheila; Stead, Joan; Weedon, Elisabet; Wright, Kevin

    2010-01-01

    New additional support-needs legislation in Scotland sought to recognise the way in which poverty, as well as individual impairment, contribute to the creation of children's difficulties in learning. As well as identifying a wider range of needs, the legislation sought to provide parents, irrespective of social background, with more powerful means…

  6. Longevity of emplacement drift ground support materials

    SciTech Connect

    Tang, David

    2000-04-01

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for the selection of materials for ground support that will function throughout the preclosure period of a potential repository at Yucca Mountain. The Development Plan (DP) for this analysis is given in Longevity of Emplacement Drift Ground Support Materials (CRWMS M and O 1999a). The objective of this analysis is to update the previous analysis (CRWMS M and O 2000a) to account for related changes in the Ground Control System Description Document (CRWMS M and O 2000b), the Monitored Geologic Repository Project Description Document (CRWMS M and O 1999b), and in environmental conditions, and to provide updated information on candidate ground support materials.

  7. Materials processing in space program support

    NASA Technical Reports Server (NTRS)

    Glicksman, Martin; Vanalstine, James M.

    1987-01-01

    Activities in support of NASA's Materials Processing in Space (MPS) program are reported. The overall task of the MPS project support contract was to provide the organization and administration of colloquiums, science reviews, workshops, technical meetings, bibliographic services, and visiting scientist programs. The research objectives and accomplishments of the University Space Research Association visiting scientist team are also summarized.

  8. Longevity of Emplacement Drift Ground Support Materials

    SciTech Connect

    D. Tang

    2000-01-07

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for selection of materials for ground support that will function throughout the preclosure period. The Development Plan (DP) for this analysis is given in CRWMS M&O (Civilian Radioactive Waste Management System Management and Operating Contractor) (1999a). The candidate materials for ground support are steel (carbon steel, ductile cast iron, galvanized steel, and stainless steel, etc.) and cement. Steel will mainly be used for steel sets, lagging, channels, rock bolts, and wire mesh. Cement usage is only considered in the case of grouted rock bolts. The candidate materials for the invert structure are steel and crushed rock ballast. The materials shall be evaluated for the repository emplacement drift environment under a specific thermal loading condition based on the proposed License Application Design Selection (LADS) design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground control materials for use in emplacement drifts. (2) Review existing documents concerning behavior of candidate ground control materials during the preclosure period. The major criteria to be considered for steel are mechanical and thermal properties, and durability, of which corrosion is the most important concern. (3) Evaluate the available results and develop recommendations for material(s) to be used.

  9. Additives in Bituminous Materials and Fuel-Resistant Sealers

    DTIC Science & Technology

    1994-08-01

    AD-A285 748 D)OT/FAAICT-94/78 DOT/FAAtRD-93/30 Additives in Bituminous FA Tehnia Cer Materials and Fuel-Resistant Atlantic City International Airport...Subtitle Ro Dat August 1394 Additives in Bituminous Materials and Fuel-Resistant S •O..M0aMtioiCOd5 Sealers I Amdirw S Polwo ovwm ’n New, No Gary L...bituminous materials and fuel-resistant sealers. Included in this report is a brief hisLory of these types of additives, the results of an airport

  10. Additive Technology: Update on Current Materials and Applications in Dentistry.

    PubMed

    Barazanchi, Abdullah; Li, Kai Chun; Al-Amleh, Basil; Lyons, Karl; Waddell, J Neil

    2017-02-01

    Additive manufacturing or 3D printing is becoming an alternative to subtractive manufacturing or milling in the area of computer-aided manufacturing. Research on material for use in additive manufacturing is ongoing, and a wide variety of materials are being used or developed for use in dentistry. Some materials, however, such as cobalt chromium, still lack sufficient research to allow definite conclusions about the suitability of their use in clinical dental practice. Despite this, due to the wide variety of machines that use additive manufacturing, there is much more flexibility in the build material and geometry when building structures compared with subtractive manufacturing. Overall additive manufacturing produces little material waste and is energy efficient when compared to subtractive manufacturing, due to passivity and the additive layering nature of the build process. Such features make the technique suitable to be used with fabricating structures out of hard to handle materials such as cobalt chromium. The main limitations of this technology include the appearance of steps due to layering of material and difficulty in fabricating certain material generally used in dentistry for use in 3D printing such as ceramics. The current pace of technological development, however, promises exciting possibilities.

  11. Longevity of Emplacement Drift Ground Support Materials

    SciTech Connect

    Tang, David H.

    2001-05-30

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for the selection of materials for ground support that will function throughout the preclosure period of a potential repository at Yucca Mountain. REV 01 ICN 01 of this analysis is developed in accordance with AP-3.10Q, Analyses and Models, Revision 2, ICN 4, and prepared in accordance with the Technical Work Plan for Subsurface Design Section FY 01 Work Activities (CRWMS M&O 2001a). The objective of this analysis is to update the previous analysis (CRWMS M&O 2000a) to account for related changes in the Ground Control System Description Document (CRWMS M&O 2000b), the Monitored Geologic Repository Project Description Document, which is included in the Requirements and Criteria for Implementing a Repository Design that can be Operated Over a Range of Thermal Modes (BSC 2001), input information, and in environmental conditions, and to provide updated information on candidate ground support materials. Candidate materials for ground support are carbon steel and cement grout. Steel is mainly used for steel sets, lagging, channel, rock bolts, and wire mesh. Cement grout is only considered in the case of grouted rock bolts. Candidate materials for the emplacement drift invert are carbon steel and granular natural material. Materials are evaluated for the repository emplacement drift environment based on the updated thermal loading condition and waste package design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground support materials for use in emplacement drifts. (2) Review existing documents concerning the behavior of candidate ground support materials during the preclosure period. (3) Evaluate impacts of temperature and radiation effects on mechanical and thermal properties of steel. Assess corrosion potential of steel at emplacement drift environment. (4) Evaluate factors

  12. Warfighter Support: DOD Needs Additional Steps to Fully Integrate Operational Contract Support into Contingency Planning

    DTIC Science & Technology

    2013-02-01

    Planning Report to the Chairman, Subcommittee on Contracting Oversight, Committee on Homeland Security and Governmental Affairs, U.S. Senate...TITLE AND SUBTITLE Warfighter Support: DOD Needs Additional Steps to Fully Integrate Operational Contract Support into Contingency Planning 5a...Support into Contingency Planning Why GAO Did This Study DOD has relied extensively on contractors for operations in Iraq and Afghanistan over the

  13. Thermodynamically consistent microstructure prediction of additively manufactured materials

    NASA Astrophysics Data System (ADS)

    Smith, Jacob; Xiong, Wei; Cao, Jian; Liu, Wing Kam

    2016-03-01

    Additive manufacturing has risen to the top of research interest in advanced manufacturing in recent years due to process flexibility, achievability of geometric complexity, and the ability to locally modify and optimize materials. The present work is focused on providing an approach for incorporating thermodynamically consistent properties and microstructure evolution for non-equilibrium supercooling, as observed in additive manufacturing processes, into finite element analysis. There are two primary benefits of this work: (1) the resulting prediction is based on the material composition and (2) the nonlinear behavior caused by the thermodynamic properties of the material during the non-equilibrium solution is accounted for with extremely high resolution. The predicted temperature response and microstructure evolution for additively manufactured stainless steel 316L using standard handbook-obtained thermodynamic properties are compared with the thermodynamic properties calculated using the CALculation of PHAse Diagrams (CALPHAD) approach. Data transfer from the CALPHAD approach to finite element analysis is discussed.

  14. Methods for the additive manufacturing of semiconductor and crystal materials

    SciTech Connect

    Stowe, Ashley C.; Speight, Douglas

    2016-11-22

    A method for the additive manufacturing of inorganic crystalline materials, including: physically combining a plurality of starting materials that are used to form an inorganic crystalline compound to be used as one or more of a semiconductor, scintillator, laser crystal, and optical filter; heating or melting successive regions of the combined starting materials using a directed heat source having a predetermined energy characteristic, thereby facilitating the reaction of the combined starting materials; and allowing each region of the combined starting materials to cool in a controlled manner, such that the desired inorganic crystalline compound results. The method also includes, prior to heating or melting the successive regions of the combined starting materials using the directed heat source, heating the combined starting materials to facilitate initial reaction of the combined starting materials. The method further includes translating the combined starting materials and/or the directed heat source between successive locations. The method still further includes controlling the mechanical, electrical, photonic, and/or optical properties of the inorganic crystalline compound.

  15. Materials Characterization of Additively Manufactured Components for Rocket Propulsion

    NASA Technical Reports Server (NTRS)

    Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

    2015-01-01

    To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRC's Additive Manufacturing roles and experimental findings will be presented.

  16. Material Characterization of Additively Manufactured Components for Rocket Propulsion

    NASA Technical Reports Server (NTRS)

    Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

    2015-01-01

    To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRCs Additive Manufacturing roles and experimental findings will be presented.

  17. Overview of Materials Qualification Needs for Metal Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Seifi, Mohsen; Salem, Ayman; Beuth, Jack; Harrysson, Ola; Lewandowski, John J.

    2016-03-01

    This overview highlights some of the key aspects regarding materials qualification needs across the additive manufacturing (AM) spectrum. AM technology has experienced considerable publicity and growth in the past few years with many successful insertions for non-mission-critical applications. However, to meet the full potential that AM has to offer, especially for flight-critical components (e.g., rotating parts, fracture-critical parts, etc.), qualification and certification efforts are necessary. While development of qualification standards will address some of these needs, this overview outlines some of the other key areas that will need to be considered in the qualification path, including various process-, microstructure-, and fracture-modeling activities in addition to integrating these with lifing activities targeting specific components. Ongoing work in the Advanced Manufacturing and Mechanical Reliability Center at Case Western Reserve University is focusing on fracture and fatigue testing to rapidly assess critical mechanical properties of some titanium alloys before and after post-processing, in addition to conducting nondestructive testing/evaluation using micro-computerized tomography at General Electric. Process mapping studies are being conducted at Carnegie Mellon University while large area microstructure characterization and informatics (EBSD and BSE) analyses are being conducted at Materials Resources LLC to enable future integration of these efforts via an Integrated Computational Materials Engineering approach to AM. Possible future pathways for materials qualification are provided.

  18. AN AZERBAIDZHAN SSR. INSTITUTE OF ADDITIVE CHEMISTRY ADDITIVES TO LUBRICATING OILS. PROBLEMS OF SYNTHESIS, INVESTIGATION AND USE OF OIL ADDITIVES; FUELS AND POLYMER MATERIALS (SELECTED ARTICLES),

    DTIC Science & Technology

    An Azerbaidzhan SSR. Institute of additive chemistry additives to lubricating oils . Problems of synthesis, investigation and use of oil additives; fuels and polymer materials (Selected articles)--Translation.

  19. Complex metallic alloys as new materials for additive manufacturing

    PubMed Central

    Kenzari, Samuel; Bonina, David; Marie Dubois, Jean; Fournée, Vincent

    2014-01-01

    Additive manufacturing processes allow freeform fabrication of the physical representation of a three-dimensional computer-aided design (CAD) data model. This area has been expanding rapidly over the last 20 years. It includes several techniques such as selective laser sintering and stereolithography. The range of materials used today is quite restricted while there is a real demand for manufacturing lighter functional parts or parts with improved functional properties. In this article, we summarize recent work performed in this field, introducing new composite materials containing complex metallic alloys. These are mainly Al-based quasicrystalline alloys whose properties differ from those of conventional alloys. The use of these materials allows us to produce light-weight parts consisting of either metal–matrix composites or of polymer–matrix composites with improved properties. Functional parts using these alloys are now commercialized. PMID:27877661

  20. Complex metallic alloys as new materials for additive manufacturing.

    PubMed

    Kenzari, Samuel; Bonina, David; Marie Dubois, Jean; Fournée, Vincent

    2014-04-01

    Additive manufacturing processes allow freeform fabrication of the physical representation of a three-dimensional computer-aided design (CAD) data model. This area has been expanding rapidly over the last 20 years. It includes several techniques such as selective laser sintering and stereolithography. The range of materials used today is quite restricted while there is a real demand for manufacturing lighter functional parts or parts with improved functional properties. In this article, we summarize recent work performed in this field, introducing new composite materials containing complex metallic alloys. These are mainly Al-based quasicrystalline alloys whose properties differ from those of conventional alloys. The use of these materials allows us to produce light-weight parts consisting of either metal-matrix composites or of polymer-matrix composites with improved properties. Functional parts using these alloys are now commercialized.

  1. Complex metallic alloys as new materials for additive manufacturing

    NASA Astrophysics Data System (ADS)

    Kenzari, Samuel; Bonina, David; Dubois, Jean Marie; Fournée, Vincent

    2014-04-01

    Additive manufacturing processes allow freeform fabrication of the physical representation of a three-dimensional computer-aided design (CAD) data model. This area has been expanding rapidly over the last 20 years. It includes several techniques such as selective laser sintering and stereolithography. The range of materials used today is quite restricted while there is a real demand for manufacturing lighter functional parts or parts with improved functional properties. In this article, we summarize recent work performed in this field, introducing new composite materials containing complex metallic alloys. These are mainly Al-based quasicrystalline alloys whose properties differ from those of conventional alloys. The use of these materials allows us to produce light-weight parts consisting of either metal-matrix composites or of polymer-matrix composites with improved properties. Functional parts using these alloys are now commercialized.

  2. Mechanical characterisation of additively manufactured material having lattice microstructure

    NASA Astrophysics Data System (ADS)

    Cuan-Urquizo, E.; Yang, S.; Bhaskar, A.

    2015-02-01

    Many natural and engineered structures possess cellular and porous architecture. This paper is focused on the mechanical characterisation of additively manufactured lattice structures. The lattice consists of a stack of polylactic acid (PLA) filaments in a woodpile arrangement fabricated using a fused deposition modelling 3D printer. Some of the most promising applications of this 3D lattice material of this type include scaffolds for tissue engineering and the core for sandwich panels. While there is a significant body of work concerning the manufacture of such lattice materials, attempts to understand their mechanical properties are very limited. This paper brings together manufacturing with the need to understand the structure-property relationship for this class of materials. In order to understand the elastic response of the PLA-based lattice structures obtained from the fused deposition modelling process, single filaments manufactured using the same process were experimentally characterised first. The single PLA filaments were manufactured under different temperatures. These filaments were then characterised by using tensile testing. The stress-strain curves are presented. The variability of the measured results is discussed. The measured properties are then taken as input to a finite element model of the lattice material. This model uses simple one-dimensional elements in conjunction with a novel method achieving computational economy which precludes the use of fine meshes. Using this novel model, the apparent elastic modulus of lattice along the filaments has been obtained and is presented in this paper.

  3. Rapid Solidification and Phase Transformations in Additive Manufactured Materials

    DOE PAGES

    Asle Zaeem, Mohsen; Clarke, Amy Jean

    2016-01-14

    Within the past few years, additive manufacturing (AM) has emerged as a promising manufacturing technique to enable the production of complex engineering structures with high efficiency and accuracy. Among the important factors establishing AM as a sustainable manufacturing process is the ability to control the microstructures and properties of AM products. In most AM processes, such as laser sintering (LS), laser melting (LM), and laser metal deposition (LMD), rapid solidification and high-temperature phase transformations play primary roles in determining nano- and microstructures, and consequently the mechanical and other properties of AM products. This topic of JOM is dedicated to summarizingmore » the current research efforts in the area of rapid solidification and phase transformations in additively manufactured materials. Finally, a brief summary follows below of 10 journal articles in this topic.« less

  4. Rapid Solidification and Phase Transformations in Additive Manufactured Materials

    SciTech Connect

    Asle Zaeem, Mohsen; Clarke, Amy Jean

    2016-01-14

    Within the past few years, additive manufacturing (AM) has emerged as a promising manufacturing technique to enable the production of complex engineering structures with high efficiency and accuracy. Among the important factors establishing AM as a sustainable manufacturing process is the ability to control the microstructures and properties of AM products. In most AM processes, such as laser sintering (LS), laser melting (LM), and laser metal deposition (LMD), rapid solidification and high-temperature phase transformations play primary roles in determining nano- and microstructures, and consequently the mechanical and other properties of AM products. This topic of JOM is dedicated to summarizing the current research efforts in the area of rapid solidification and phase transformations in additively manufactured materials. Finally, a brief summary follows below of 10 journal articles in this topic.

  5. Defense Support of Civil Authorities: DOD Mission or Additional Duty

    DTIC Science & Technology

    2010-12-14

    Illustrations iv Biography v Introduction 1 Background 2 DSCA Execution 7 DSCA Shortfalls...12 Recommendations 16 Conclusion 19 Bibliography 21 Illustrations Page Figure 1 . Map of 10 FEMA Regions...the United Kingdom …” 1 More than 72,000 uniformed military members deployed in support of the Katrina response to save lives, mitigate human

  6. Exploration Life Support: ELS Functions and Materials Interfaces

    NASA Technical Reports Server (NTRS)

    Duffield, Bruce

    2007-01-01

    This viewgraph presentation reviews some of the processes used to develop life support systems, and how that supports the materials that are selected. Of particular concern in the selection of materials is flammability.

  7. Multiscale and Multiphysics Modeling of Additive Manufacturing of Advanced Materials

    NASA Technical Reports Server (NTRS)

    Liou, Frank; Newkirk, Joseph; Fan, Zhiqiang; Sparks, Todd; Chen, Xueyang; Fletcher, Kenneth; Zhang, Jingwei; Zhang, Yunlu; Kumar, Kannan Suresh; Karnati, Sreekar

    2015-01-01

    The objective of this proposed project is to research and develop a prediction tool for advanced additive manufacturing (AAM) processes for advanced materials and develop experimental methods to provide fundamental properties and establish validation data. Aircraft structures and engines demand materials that are stronger, useable at much higher temperatures, provide less acoustic transmission, and enable more aeroelastic tailoring than those currently used. Significant improvements in properties can only be achieved by processing the materials under nonequilibrium conditions, such as AAM processes. AAM processes encompass a class of processes that use a focused heat source to create a melt pool on a substrate. Examples include Electron Beam Freeform Fabrication and Direct Metal Deposition. These types of additive processes enable fabrication of parts directly from CAD drawings. To achieve the desired material properties and geometries of the final structure, assessing the impact of process parameters and predicting optimized conditions with numerical modeling as an effective prediction tool is necessary. The targets for the processing are multiple and at different spatial scales, and the physical phenomena associated occur in multiphysics and multiscale. In this project, the research work has been developed to model AAM processes in a multiscale and multiphysics approach. A macroscale model was developed to investigate the residual stresses and distortion in AAM processes. A sequentially coupled, thermomechanical, finite element model was developed and validated experimentally. The results showed the temperature distribution, residual stress, and deformation within the formed deposits and substrates. A mesoscale model was developed to include heat transfer, phase change with mushy zone, incompressible free surface flow, solute redistribution, and surface tension. Because of excessive computing time needed, a parallel computing approach was also tested. In addition

  8. ANALYSIS OF MPC ACCESS REQUIREMENTS FOR ADDITION OF FILLER MATERIALS

    SciTech Connect

    W. Wallin

    1996-09-03

    This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development Department (WPDD) in response to a request received via a QAP-3-12 Design Input Data Request (Ref. 5.1) from WAST Design (formerly MRSMPC Design). The request is to provide: Specific MPC access requirements for the addition of filler materials at the MGDS (i.e., location and size of access required). The objective of this analysis is to provide a response to the foregoing request. The purpose of this analysis is to provide a documented record of the basis for the response. The response is stated in Section 8 herein. The response is based upon requirements from an MGDS perspective.

  9. Progress Towards Metal Additive Manufacturing Standardization to Support Qualification and Certification

    NASA Astrophysics Data System (ADS)

    Seifi, Mohsen; Gorelik, Michael; Waller, Jess; Hrabe, Nik; Shamsaei, Nima; Daniewicz, Steve; Lewandowski, John J.

    2017-03-01

    As the metal additive manufacturing (AM) industry moves towards industrial production, the need for qualification standards covering all aspects of the technology becomes ever more prevalent. While some standards and specifications for documenting the various aspects of AM processes and materials exist and continue to evolve, many such standards still need to be matured or are under consideration/development within standards development organizations. An important subset of this evolving the standardization domain has to do with critical property measurements for AM materials. While such measurement procedures are well documented, with various legacy standards for conventional metallic material forms such as cast or wrought structural alloys, many fewer standards are currently available to enable systematic evaluation of those properties in AM-processed metallic materials. This is due in part to the current lack of AM-specific standards and specifications for AM materials and processes, which are a logical precursor to the material characterization standards for any material system. This paper summarizes some of the important standardization activities, as well as limitations associated with using currently available standards for metal AM with a focus on measuring mission-critical properties. Technical considerations in support of future standards development, as well as a pathway for qualification/certification of AM parts enabled by the appropriate standardization landscape, are discussed.

  10. Additional support for the TDK/MABL computer program

    NASA Technical Reports Server (NTRS)

    Nickerson, G. R.; Dunn, Stuart S.

    1993-01-01

    An advanced version of the Two-Dimensional Kinetics (TDK) computer program was developed under contract and released to the propulsion community in early 1989. Exposure of the code to this community indicated a need for improvements in certain areas. In particular, the TDK code needed to be adapted to the special requirements imposed by the Space Transportation Main Engine (STME) development program. This engine utilizes injection of the gas generator exhaust into the primary nozzle by means of a set of slots. The subsequent mixing of this secondary stream with the primary stream with finite rate chemical reaction can have a major impact on the engine performance and the thermal protection of the nozzle wall. In attempting to calculate this reacting boundary layer problem, the Mass Addition Boundary Layer (MABL) module of TDK was found to be deficient in several respects. For example, when finite rate chemistry was used to determine gas properties, (MABL-K option) the program run times became excessive because extremely small step sizes were required to maintain numerical stability. A robust solution algorithm was required so that the MABL-K option could be viable as a rocket propulsion industry design tool. Solving this problem was a primary goal of the phase 1 work effort.

  11. Additive manufacturing of stretchable tactile sensors: Processes, materials, and applications

    NASA Astrophysics Data System (ADS)

    Vatani, Morteza

    3D printing technology is becoming more ubiquitous every day especially in the area of smart structures. However, fabrication of multi-material, functional, and smart structures is problematic because of the process and material limitations. This thesis sought to develop a Direct Print Photopolymerization (DPP) fabrication technique that appreciably extends the manufacturing space for the 3D smart structures. This method employs a robotically controlled micro-extrusion of a filament equipped with a photopolymerization process. The ability to use polymers and ultimately their nanocomposites in this process is the advantage of the proposed process over the current fabrication methods in the fabrication of 3D structures featuring mechanical, physical, and electrical functionalities. In addition, this study focused to develop a printable, conductive, and stretchable nanocomposite based on a photocurable and stretchable liquid resin filled with multi-walled carbon nanotubes (MWNTs). This nanocomposite exhibited piezoresistivity, means its resistivity changes as it deforms. This property is a favorable factor in developing resistance based tactile sensors. They were also able to resist high tensile strains while they showed conductivity. Furthermore, this study offered a possible and low-cost method to have a unique and highly stretchable pressure sensitive polymer. This disruptive pressure sensitive polymer composed of an Ionic Liquid (IL) and a stretchable photopolymer embedded between two layers of Carbon Nanotube (CNTs) based stretchable electrodes. The developed IL-polymer showed both field effect property and piezoresistivity that can detect large tensile strains up 30%. In summary, this research study focused to present feasible methods and materials for printing a 3D smart structure especially in the context of flexible tactile sensors. This study provides a foundation for the future efforts in fabrication of skin like tactile sensors in three-dimensional motifs

  12. Effective Mechanical Properties of Lattice Material Fabricated by Material Extrusion Additive Manufacturing

    SciTech Connect

    Park, Sang-In; Choi, Seung-kyum; Rosen, David W; Duty, Chad E

    2014-01-01

    In this paper, a two-step homogenization method is proposed and implemented for evaluating effective mechanical properties of lattice structured material fabricated by the material extrusion additive manufacturing process. In order to consider the characteristics of the additive manufacturing process in estimation procedures, the levels of scale for homogenization are divided into three stages the levels of layer deposition, structural element, and lattice structure. The method consists of two transformations among stages. In the first step, the transformation between layer deposition and structural element levels is proposed to find the geometrical and material effective properties of structural elements in the lattice structure. In the second step, the method to estimate effective mechanical properties of lattice material is presented, which uses a unit cell and is based on the discretized homogenization method for periodic structure. The method is implemented for cubic lattice structure and compared to experimental results for validation purposes.

  13. Timing of Getter Material Addition in Cementitious Wasteforms

    NASA Astrophysics Data System (ADS)

    Lawter, A.; Qafoku, N. P.; Asmussen, M.; Neeway, J.; Smith, G. L.

    2015-12-01

    A cementitious waste form, Cast Stone, is being evaluated as a possible supplemental immobilization technology for the Hanford sites's low activity waste (LAW), which contains radioactive 99Tc and 129I, as part of the tank waste cleanup mission. Cast Stone is made of a dry blend 47% blast furnace slag, 45% fly ash, and 8% ordinary Portland cement, mixed with a low-activity waste (LAW). To improve the retention of Tc and/or I in Cast Stone, materials with a high affinity for Tc and/or I, termed "getters," can be added to provide a stable domain for the radionuclides of concern. Previous testing conducted with a variety of getters has identified Tin(II)-Apatite and Silver Exchanged Zeolite as promising candidates for Tc and I, respectively. Investigation into the sequence in which getters are added to Cast Stone was performed following two methods: 1) adding getters to the Cast Stone dry blend, and then mixing with liquid waste, and 2) adding getters to the liquid waste first, followed by addition of the Cast Stone dry blend. Cast Stone monolith samples were prepared with each method and leach tests, following EPA method 1315, were conducted in either distilled water or simulated vadose zone porewater for a period of up to 63 days. The leachate was analyzed for Tc, I, Na, NO3-, NO2- and Cr with ICP-MS, ICP-OES and ion chromatography and the results indicated that the Cast Stone with getter addition in the dry blend mix (method 1) has lower rates of Tc and I leaching. The mechanisms of radionuclide release from the Cast Stone were also investigated with a variety of solid phase characterization techniques of the monoliths before and after leaching, such as XRD, SEM/EDS, TEM/SAED and other spectroscopic techniques.

  14. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  15. Additive Manufacturing Materials Study for Gaseous Radiation Detection

    SciTech Connect

    Steer, C.A.; Durose, A.; Boakes, J.

    2015-07-01

    Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

  16. Indirect additive manufacturing as an elegant tool for the production of self-supporting low density gelatin scaffolds.

    PubMed

    Van Hoorick, Jasper; Declercq, Heidi; De Muynck, Amelie; Houben, Annemie; Van Hoorebeke, Luc; Cornelissen, Ria; Van Erps, Jürgen; Thienpont, Hugo; Dubruel, Peter; Van Vlierberghe, Sandra

    2015-10-01

    The present work describes for the first time the production of self-supporting low gelatin density (<10 w/v%) porous scaffolds using methacrylamide-modified gelatin as an extracellular matrix mimicking component. As porous scaffolds starting from low gelatin concentrations cannot be realized with the conventional additive manufacturing techniques in the abscence of additives, we applied an indirect fused deposition modelling approach. To realize this, we have printed a sacrificial polyester scaffold which supported the hydrogel material during UV crosslinking, thereby preventing hydrogel structure collapse. After complete curing, the polyester scaffold was selectively dissolved leaving behind a porous, interconnective low density gelatin scaffold. Scaffold structural analysis indicated the success of the selected indirect additive manufacturing approach. Physico-chemical testing revealed scaffold properties (mechanical, degradation, swelling) to depend on the applied gelatin concentration and methacrylamide content. Preliminary biocompatibility studies revealed the cell-interactive and biocompatible properties of the materials developed.

  17. Fabrication of Turbine Disk Materials by Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Sudbrack, Chantal; Bean, Quincy A.; Cooper, Ken; Carter, Robert; Semiatin, S. Lee; Gabb, Tim

    2014-01-01

    Precipitation-strengthened, nickel-based superalloys are widely used in the aerospace and energy industries due to their excellent environmental resistance and outstanding mechanical properties under extreme conditions. Powder-bed additive manufacturing (AM) technologies offer the potential to revolutionize the processing of superalloy turbine components by eliminating the need for extensive inventory or expensive legacy tooling. Like selective laser melting (SLM), electron beam melting (EBM) constructs three-dimensional dense components layer-by-layer by melting and solidification of atomized, pre-alloyed powder feedstock within 50-200 micron layers. While SLM has been more widely used for AM of nickel alloys like 718, EBM offers several distinct advantages, such as less retained residual stress, lower risk of contamination, and faster build rates with multiple-electron-beam configurations. These advantages are particularly attractive for turbine disks, for which excessive residual stress and contamination can shorten disk life during high-temperature operation. In this presentation, we will discuss the feasibility of fabricating disk superalloy components using EBM AM. Originally developed using powder metallurgy forging processing, disk superalloys contain a higher refractory content and precipitate volume fraction than alloy 718, thus making them more prone to thermal cracking during AM. This and other challenges to produce homogeneous builds with desired properties will be presented. In particular, the quality of lab-scale samples fabricated via a design of experiments, in which the beam current, build temperature, and beam velocity were varied, will be summarized. The relationship between processing parameters, microstructure, grain orientation, and mechanical response will be discussed.

  18. Tungsten materials as durable catalyst supports for fuel cell electrodes

    NASA Astrophysics Data System (ADS)

    Perchthaler, M.; Ossiander, T.; Juhart, V.; Mitzel, J.; Heinzl, C.; Scheu, C.; Hacker, V.

    2013-12-01

    Durable platinum catalyst support materials, e.g. tungsten carbide (WC), tungsten oxide (WOx) and self-synthesized tungsten oxide (WOxs) were evaluated for the use in High-Temperature Proton Exchange Fuel Cells (HT-PEM) based on phosphoric acid doped polybenzimidazole as electrolyte. The support materials and the catalyst loaded support materials were characterized ex-situ by cyclic voltammetry in HClO4, potential cycling, CO-stripping, electron microscopy and X-ray diffraction measurements. The tungsten oxide and tungsten carbide based supported catalysts were compared to High Surface Area Carbon (HSAC), each coated with platinum via the same in-house manufacturing procedures. The in-house manufacturing procedures resulted in catalyst particle sizes on HSAC of 3-4 nm with a uniform distribution. The in-situ Potential Cycling experiments of WOx or WOxs supported catalysts showed much lower degradation rates compared to High Surface Area Carbons. The formation of WOx species on WC was proven by ex- and in-situ cyclic voltammetric studies and thermogravimetric analyses. X-ray diffraction, ex-situ cyclic voltammetry and in-situ cyclic voltammetry showed that WOx is formed from WC as starting material under oxidizing conditions. Finally a 1000 h durability test with WOx as catalyst support material on the anode was done in a HT-PEM fuel cell with reformed methanol on the anode.

  19. Poly(ether ester) Ionomers as Water-Soluble Polymers for Material Extrusion Additive Manufacturing Processes.

    PubMed

    Pekkanen, Allison M; Zawaski, Callie; Stevenson, André T; Dickerman, Ross; Whittington, Abby R; Williams, Christopher B; Long, Timothy E

    2017-04-12

    Water-soluble polymers as sacrificial supports for additive manufacturing (AM) facilitate complex features in printed objects. Few water-soluble polymers beyond poly(vinyl alcohol) enable material extrusion AM. In this work, charged poly(ether ester)s with tailored rheological and mechanical properties serve as novel materials for extrusion-based AM at low temperatures. Melt transesterification of poly(ethylene glycol) (PEG, 8k) and dimethyl 5-sulfoisophthalate afforded poly(ether ester)s of sufficient molecular weight to impart mechanical integrity. Quantitative ion exchange provided a library of poly(ether ester)s with varying counterions, including both monovalent and divalent cations. Dynamic mechanical and tensile analysis revealed an insignificant difference in mechanical properties for these polymers below the melting temperature, suggesting an insignificant change in final part properties. Rheological analysis, however, revealed the advantageous effect of divalent countercations (Ca(2+), Mg(2+), and Zn(2+)) in the melt state and exhibited an increase in viscosity of two orders of magnitude. Furthermore, time-temperature superposition identified an elevation in modulus, melt viscosity, and flow activation energy, suggesting intramolecular interactions between polymer chains and a higher apparent molecular weight. In particular, extrusion of poly(PEG8k-co-CaSIP) revealed vast opportunities for extrusion AM of well-defined parts. The unique melt rheological properties highlighted these poly(ether ester) ionomers as ideal candidates for low-temperature material extrusion additive manufacturing of water-soluble parts.

  20. 16 CFR 2.20 - Petitions for review of requests for additional information or documentary material.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... additional information or documentary material. 2.20 Section 2.20 Commercial Practices FEDERAL TRADE... material, or recommend such modification to the responsible Assistant Director of the Bureau of Competition... investigation. A request for additional information or documentary material may be modified only in...

  1. Carbon nanotube synthesis with different support materials and catalysts

    NASA Astrophysics Data System (ADS)

    Gümüş, Fatih; Yuca, Neslihan; Karatepe, Nilgün

    2013-09-01

    Having remarkable characteristics, carbon nanotubes (CNTs) have attracted a lot of interest. Their mechanical, electrical, thermal and chemical properties make CNTs suitable for several applications such as electronic devices, hydrogen storage, textile, drug delivery etc. CNTs have been synthesized by various methods, such as arc discharge, laser ablation and catalytic chemical vapor deposition (CCVD). In comparison with the other techniques, CCVD is widely used as it offers a promising route for mass production. High capability of decomposing hydrocarbon formation is desired for the selected catalysts. Therefore, transition metals which are in the nanometer scale are the most effective catalysts. The common transition metals that are being used are Fe, Co, Ni and their binary alloys. The impregnation of the catalysts over the support material has a crucial importance for the CNT production. In this study, the influence of the support materials on the catalytic activity of metals was investigated. CNTs have been synthesized over alumina (Al2O3), silica (SiO2) and magnesium oxide (MgO) supported Fe, Co, Fe-Co catalysts. Catalyst - support material combinations have been investigated and optimum values for each were compared. Single walled carbon nanotubes (SWCNTs) were produced at 800°C. The duration of synthesis was 30 minutes for all support materials. The synthesized materials were characterized by thermal gravimetric analysis (TGA), Raman spectroscopy and transmission electron microscopy.

  2. The Effectiveness of Additional Literacy Support (ALS) in Years 3 and 4

    ERIC Educational Resources Information Center

    Bunn, Tim

    2008-01-01

    This study compared the progress in reading and spelling of 256 children in 11 classes in 9 English primary schools in Years 3 and 4, and a partially overlapping sample of 126 children who received additional help with literacy during 1 year. Teachers and teaching assistants used either Additional Literacy Support (ALS), a highly structured set of…

  3. 49 CFR 173.422 - Additional requirements for excepted packages containing Class 7 (radioactive) materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... containing Class 7 (radioactive) materials. 173.422 Section 173.422 Transportation Other Regulations Relating... (Radioactive) Materials § 173.422 Additional requirements for excepted packages containing Class 7 (radioactive) materials. An excepted package of Class 7 (radioactive) material that is prepared for shipment under...

  4. 49 CFR 173.422 - Additional requirements for excepted packages containing Class 7 (radioactive) materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... containing Class 7 (radioactive) materials. 173.422 Section 173.422 Transportation Other Regulations Relating... (Radioactive) Materials § 173.422 Additional requirements for excepted packages containing Class 7 (radioactive) materials. An excepted package of Class 7 (radioactive) material that is prepared for shipment under...

  5. 49 CFR 173.422 - Additional requirements for excepted packages containing Class 7 (radioactive) materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... containing Class 7 (radioactive) materials. 173.422 Section 173.422 Transportation Other Regulations Relating... (Radioactive) Materials § 173.422 Additional requirements for excepted packages containing Class 7 (radioactive) materials. An excepted package of Class 7 (radioactive) material that is prepared for shipment under...

  6. 49 CFR 173.422 - Additional requirements for excepted packages containing Class 7 (radioactive) materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... containing Class 7 (radioactive) materials. 173.422 Section 173.422 Transportation Other Regulations Relating... (Radioactive) Materials § 173.422 Additional requirements for excepted packages containing Class 7 (radioactive) materials. An excepted package of Class 7 (radioactive) material that is prepared for shipment under...

  7. 49 CFR 173.422 - Additional requirements for excepted packages containing Class 7 (radioactive) materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... containing Class 7 (radioactive) materials. 173.422 Section 173.422 Transportation Other Regulations Relating... (Radioactive) Materials § 173.422 Additional requirements for excepted packages containing Class 7 (radioactive) materials. An excepted package of Class 7 (radioactive) material that is prepared for shipment under...

  8. Support Assembly for Composite Laminate Materials During Roll Press Processing

    NASA Technical Reports Server (NTRS)

    Catella, Luke A.

    2011-01-01

    A composite laminate material is supported during the roll press processing thereof by an assembly having: first and second perforated films disposed adjacent to first and second opposing surfaces of a mixture of uncured resin and fibers defining the composite laminate material, a gas permeable encasement surrounding the mixture and the first and second films, a gas impervious envelope sealed about the gas permeable encasement, and first and second rigid plates clamped about the gas impervious envelope.

  9. Solving Additive Problems at Pre-Elementary School Level with the Support of Graphical Representation

    ERIC Educational Resources Information Center

    Selva, Ana Coelho Vieira; Falcao, Jorge Tarcisio da Rocha; Nunes, Terezinha

    2005-01-01

    This research offers empirical evidence of the importance of supplying diverse symbolic representations in order to support concept development in mathematics. Graphical representation can be a helpful symbolic tool for concept development in the conceptual field of additive structures. Nevertheless, this symbolic tool has specific difficulties…

  10. 24 CFR 574.330 - Additional standards for short-term supported housing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 3 2011-04-01 2010-04-01 true Additional standards for short-term supported housing. 574.330 Section 574.330 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND...

  11. Pedagogical Professional Self-Determination Support for Students under Conditions of Additional Education Program Implementation

    ERIC Educational Resources Information Center

    Khairutdinova, Rezeda R.; Fedorova, Yuliya A.

    2016-01-01

    Significance of the problem stated in the article is stipulated by the fact that professional self-determination of students at the stage of professional education needs pedagogical support; using resources of additional education program will let the individual make smart choices about future professional sphere. Object of the article is to work…

  12. Teachers' Perceptions of Students' Additional Support Needs: In the Eye of the Beholder?

    ERIC Educational Resources Information Center

    Bruggink, Marjon; Goei, Sui L.; Koot, Hans M.

    2016-01-01

    Nowadays, teachers are regarded as key players in the process of identifying and catering to students' additional support needs within mainstream primary classrooms. However, teachers' professional judgements regarding students with special needs have been found to be contextually influenced (e.g. by school context, student population, level of…

  13. Supporting English as an Additional Language Students in Science: Integrating Content and Language

    ERIC Educational Resources Information Center

    McCallum, Miranda; Miller, Jenny

    2013-01-01

    In this article, we report on a teacher-researcher collaboration that emerged from a large study on literacy strategies for diverse classrooms. Using the example of one Year 9 class of ten English as an Additional Language (EAL) students, we trialled language-focussed materials on the topic of Ecosystems as an alternative or adjunct to the…

  14. Conversion of syngas to light olefins over silicalite-1 supported iron and cobalt catalysts: Effects of manganese addition

    SciTech Connect

    Das, D.; Ravichandran, G.; Chakrabarty, D.K.

    1996-10-01

    As the demand for light (C2-C4) olefins, an important raw materials for a number of chemical industries, is ever increasing considerable attention is now being paid to the design of suitable catalysts with high selectivity for small chain olefins. Although Fischer-Tropsch synthesis yields a wide spectrum of products from methane to waxes it is possible to restrict the chain growth to a few carbon atoms by containing the active metal panicles inside the small pores of a suitable support like zeolite. The nature of the zeolite support also has a strong influence on the product selectivity due to secondary reactions. This paper discusses the results of syngas conversion to light olefins over iron and cobalt catalysts supported on silicalite-1. Effect of the addition of manganese which is known to improve the selectivity to light olefins is also discussed.

  15. Effect of fluoride addition on the properties of dental alginate impression materials.

    PubMed

    Lee, Yong-Keun; Lim, Bum-Soon; Kim, Cheol-We

    2004-03-01

    Fluoride-containing dental alginate impression materials can exert a considerable reduction in enamel solubility. The objective was to evaluate the effects of fluoride addition in the alginate impression materials on the properties and subsequent release of fluoride. Four experimental alginate impression materials were studied. Materials were mixed with distilled water (control) or 100-ppm fluoride solution. One or two percent NaF, or 1% SnF2 was added to the materials, which were mixed with distilled water. Fluoride release, flexibility, recovery from deformation, setting time, compressive strength and elastic modulus were determined in accordance with the ISO 1563 and ANSI/ADA Spec. 18. Fluoride release increased after addition of fluoride, and the released amount was 0.762-14.761 ppm. Addition of NaF or SnF2 resulted in higher fluoride release than the control group (p < 0.05). After fluoride addition, flexibility was 15.45-20.27%, and the recovery from deformation did not change except one material. Compressive strength after fluoride addition was 0.36-1.12 MPa. Addition of NaF or SnF2 in an alginate impression material may result in effective release of fluoride without deteriorating the properties of material itself.

  16. Nuclear Industry Support Services by the Buffalo Materials Research Center

    SciTech Connect

    Henry, L.G. )

    1993-01-01

    The Buffalo Materials Research Center (BMRC) is located on the campus of the State University of New York at Buffalo, Principal facilities within BMRC include a 2-MW PULSTAR, low-enrichment reactor, an electron accelerator, and irradiated materials remote testing facilities. The reactor and the materials testing facilities have been utilized extensively in support of the power reactor community since 1961. This paper briefly highlights the nature and scope of this service. The BMRC is operated for the university by Buffalo Materials Research, Inc., a private for-profit company, which is a subsidiary of Materials Engineering Associates, Inc. (MEA), a Maryland-based materials testing company. A primary mission of MEA has been research on the effects of neutron irradiation on reactor structural materials, including those used for pressure vessel and piping systems. The combined resources of MEA and BMRC have played a pivotal role in the assessment of reactor pressure vessel safety both in the United States and abroad and in the development of new radiation-resistant steels.

  17. Carbon recycling in materially closed ecological life support systems

    NASA Technical Reports Server (NTRS)

    Obenhuber, D. C.; Folsome, C. E.

    1988-01-01

    Results of studies are presented of materially closed energetically open microbial ecosystems or 'closed ecosystems'. These are natural marine ecosystems that have been sealed in glass containers to prevent material exchange with the environment but allow energy to pass freely through them. They represent model life support systems for the future human habitation of space. The results are discussed analytically and indicate that these ecosystems, when subjected to a constant energy flux, seem to be reliable and self-sufficient systems for recycling of biologically produced carbon compounds.

  18. Children's Recall and Motivation for an Environmental Education Video with Supporting Pedagogical Materials

    ERIC Educational Resources Information Center

    Viteri, Fátima; Clarebout, Geraldine; Crauwels, Marion

    2014-01-01

    This study examined recall (Rcl) differences of high, average and low achieving fifth-grade elementary students (72) for an environmental education video with supporting pedagogical materials. In addition, it assessed the motivational level of all students. Recall assessment was carried out one-week and twenty-weeks after intervention. Main…

  19. Electrostatic Levitation: A Tool to Support Materials Research in Microgravity

    NASA Technical Reports Server (NTRS)

    Rogers, Jan; SanSoucie, Mike

    2012-01-01

    Containerless processing represents an important topic for materials research in microgravity. Levitated specimens are free from contact with a container, which permits studies of deeply undercooled melts, and high-temperature, highly reactive materials. Containerless processing provides data for studies of thermophysical properties, phase equilibria, metastable state formation, microstructure formation, undercooling, and nucleation. The European Space Agency (ESA) and the German Aerospace Center (DLR) jointly developed an electromagnetic levitator facility (MSL-EML) for containerless materials processing in space. The electrostatic levitator (ESL) facility at the Marshall Space Flight Center provides support for the development of containerless processing studies for the ISS. Apparatus and techniques have been developed to use the ESL to provide data for phase diagram determination, creep resistance, emissivity, specific heat, density/thermal expansion, viscosity, surface tension and triggered nucleation of melts. The capabilities and results from selected ESL-based characterization studies performed at NASA's Marshall Space Flight Center will be presented.

  20. Polyethylene oxide additive-entrapped polyvinyl chloride as a new blood bag material.

    PubMed

    Lee, J H; Kim, K O; Ju, Y M

    1999-01-01

    Until now, most widely used blood bag material has been a plasticized polyvinyl chloride (PVC) because it has many desirable properties as a blood bag material. One of main concerns of using plasticized PVC as a blood bag material is the toxicity of the plasticizers that are leached out of the material. We tried to solve this problem by the addition of polyethylene oxide (PEO)-containing amphiphilic block copolymers as additives in the PVC. The PEO additives may play two roles: they can act as nontoxic plasticizers to PVC, and they can also act as blood-compatible surface modifiers. In this study, PEO additive-entrapped PVC films were prepared by the addition (up to 30 wt%) of PEO-alkyl carbon block copolymers or PEO-polypropylene oxide (PPO)-PEO triblock copolymers with different PEO chain lengths in the PVC. The prepared PEO additive-containing PVC films were characterized by the measurements of water contact angle, Fourier transform IR spectroscopy in the attenuated total reflectance mode, mechanical properties (tensile strength and elongation at break), water absorption, and stability of the PEO additives entrapped in the films. It was observed that the PEO additive-entrapped PVC films were flexible and transparent. It seems that the PEO additives are surface active, resulting in the considerable change of surface characteristics without a significant change of the mechanical properties of the films compared to the control PVC without any additives or a commercial blood bag. The adhesion of platelets on the film surfaces was significantly reduced by the addition of PEO additives. It seems that 10% addition of PEO additives is enough for the suppression of platelet adhesion on the surfaces. This study demonstrated that the use of PEO-containing block copolymers as additives to the PVC can be a feasible approach to prepare a new type of blood bag.

  1. Analysis of Additional CFT Support at Z=0 for the Silicon Half Trough

    SciTech Connect

    Cease, H.; Lee, A.; /Fermilab

    2000-03-20

    The D-Zero silicon trough is segmented into two half troughs. Loading to the Central Fiber Tracker Barrel 1 is at both ends and near Z = 0. The loading near Z = 0 is thought to be 4 lbs at 4 points. The point locations are at +/-45 degrees for each half trough on each side of Z = O. An additional support at Z = O is required to prevent beam sag and out of round distortions to the CFT Barrel 1. An additional joining washer will be attached between barrels 1 and 2 at Z = 0. Also a support ring will be attached to the inner diameter of barrel 1 to further help in out of round distortions. Details of the washer and loading are modeled using ANSYS.

  2. The biobehavioral family model: testing social support as an additional exogenous variable.

    PubMed

    Woods, Sarah B; Priest, Jacob B; Roush, Tara

    2014-12-01

    This study tests the inclusion of social support as a distinct exogenous variable in the Biobehavioral Family Model (BBFM). The BBFM is a biopsychosocial approach to health that proposes that biobehavioral reactivity (anxiety and depression) mediates the relationship between family emotional climate and disease activity. Data for this study included married, English-speaking adult participants (n = 1,321; 55% female; M age = 45.2 years) from the National Comorbidity Survey Replication, a nationally representative epidemiological study of the frequency of mental disorders in the United States. Participants reported their demographics, marital functioning, social support from friends and relatives, anxiety and depression (biobehavioral reactivity), number of chronic health conditions, and number of prescription medications. Confirmatory factor analyses supported the items used in the measures of negative marital interactions, social support, and biobehavioral reactivity, as well as the use of negative marital interactions, friends' social support, and relatives' social support as distinct factors in the model. Structural equation modeling indicated a good fit of the data to the hypothesized model (χ(2)  = 846.04, p = .000, SRMR = .039, CFI = .924, TLI = .914, RMSEA = .043). Negative marital interactions predicted biobehavioral reactivity (β = .38, p < .001), as did relatives' social support, inversely (β = -.16, p < .001). Biobehavioral reactivity predicted disease activity (β = .40, p < .001) and was demonstrated to be a significant mediator through tests of indirect effects. Findings are consistent with previous tests of the BBFM with adult samples, and suggest the important addition of family social support as a predicting factor in the model.

  3. Compositions, Functions, and Testing of Friction Brake Materials and Their Additives

    SciTech Connect

    Blau, PJ

    2001-10-22

    The purpose of this report is to present a survey of commercial brake materials and additives, and to indicate their typical properties and functions, especially as regards their use in heavy trucks. Most truck pad and shoe materials described here were designed to wear against cast iron. Brake material test methods are also briefly described. This report does not address issues associated with the fabrication and manufacturing of brake materials. Since there are literally thousands of brake material additives, and their combinations are nearly limitless, it is impractical to list them all here. Rather, an attempt has been made to capture the primary constituents and their functions. An Appendix contains thermo-physical properties of some current and potential brake materials.

  4. Intelligence is as intelligence does: can additional support needs replace disability?

    PubMed

    Arnold, Samuel R C; Riches, Vivienne C; Stancliffe, Roger J

    2011-12-01

    Abstract In many developed cultures there is an assumption that IQ is intelligence. However, emerging theories of multiple intelligences, of emotional intelligence, as well as the application of IQ testing to other cultural groups, and to people with disability, raises many questions as to what IQ actually measures. Despite recent research that shows IQ testing produces a floor effect when applied to people with lower IQ, as well as research that shows the Flynn effect also applies to people with lower IQ, in practice IQ scores below a certain cut-off are still being used to determine and classify a person's intellectual disability. However, a new paradigm is emerging, almost returning to the original intent of Binet, where measurement is made of the supports the person needs. In this paper, we argue that if one extends the notions of this supports paradigm that diagnosis of intellectual or physical disability could potentially be replaced by diagnosis of additional intellectual support needs, or additional physical support needs.

  5. 12 CFR 367.15 - Additional proceedings as to disputed material facts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... facts. 367.15 Section 367.15 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND... Additional proceedings as to disputed material facts. (a) In actions not based upon a conviction or civil... facts material to the proposed suspension and/or exclusion, the contractor shall be afforded...

  6. 12 CFR 367.15 - Additional proceedings as to disputed material facts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... facts. 367.15 Section 367.15 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND... Additional proceedings as to disputed material facts. (a) In actions not based upon a conviction or civil... facts material to the proposed suspension and/or exclusion, the contractor shall be afforded...

  7. 36 CFR 1206.86 - What additional materials must I submit with the final narrative report?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false What additional materials must I submit with the final narrative report? 1206.86 Section 1206.86 Parks, Forests, and Public... narrative report? You must submit the materials determined by the Commission as found in the NHPRC...

  8. Survival of Listeria monocytogenes on a conveyor belt material with or without antimicrobial additives.

    PubMed

    Chaitiemwong, N; Hazeleger, W C; Beumer, R R

    2010-08-15

    Survival of Listeria monocytogenes on a conveyor belt material with or without antimicrobial additives, in the absence or presence of food debris from meat, fish and vegetables and at temperatures of 10, 25 and 37 degrees C was investigated. The pathogen survived best at 10 degrees C, and better at 25 degrees C than at 37 degrees C on both conveyor belt materials. The reduction in the numbers of the pathogen on belt material with antimicrobial additives in the first 6h at 10 degrees C was 0.6 log unit, which was significantly higher (P<0.05) than the reduction of 0.2 log unit on belt material without additives. Reductions were significantly less (P<0.05) in the presence of food residue. At 37 degrees C and 20% relative humidity, large decreases in the numbers of the pathogen on both conveyor belt materials during the first 6h were observed. Under these conditions, there was no obvious effect of the antimicrobial substances. However, at 25 degrees C and 10 degrees C and high humidity (60-75% rh), a rapid decrease in bacterial numbers on the belt material with antimicrobial substances was observed. Apparently the reduction in numbers of L. monocytogenes on belt material with antimicrobial additives was greater than on belt material without additives only when the surfaces were wet. Moreover, the presence of food debris neutralized the effect of the antimicrobials. The results suggest that the antimicrobial additives in conveyor belt material could help to reduce numbers of microorganisms on belts at low temperatures when food residues are absent and belts are not rapidly dried.

  9. Flammability, Odor, Offgassing, and Compatibility Requirements and Test Procedures for Materials in Environments that Support Combustion

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This handbook establishes NASA program requirements for evaluation, testing, and selection of materials to preclude unsafe conditions related to flammability, odor, offgassing, and fluid compatibility. Materials intended for use in space vehicles, specified test facilities, and specified ground support equipment (GSE) must meet the requirements of this document. Additional materials performance requirements may be specified in other program or NASA center specific documentation. Responsible NASA centers materials organizations must include applicable requirements of this document in their materials control programs. Materials used in habitable areas of spacecraft, including the materials of the spacecraft, stowed equipment, and experiments, must be evaluated for flammability, odor, and offgassing characteristics. All materials used in other areas must be evaluated for flammability characteristics. In addition, materials that are exposed to liquid oxygen (LOX), gaseous oxygen (GOX), and other reactive fluids' must be evaluated for compatibility with the fluid in their use application. Materials exposed to pressurized breathing gases also must be evaluated for odor and offgassing characteristics. The worst-case anticipated use environment (most hazardous pressure, temperature, material thickness, and fluid exposure conditions) must be used in the evaluation process. Materials that have been shown to meet the criteria of the required tests are acceptable for further consideration in design. Whenever possible, materials should be selected that have already been shown to meet the test criteria in the use environment. Existing test data are compiled in the NASA Marshall Space Flight Center (MSFC) Materials and Processes Technical Information System (MAPTIS) and published periodically as the latest revision of a joint document with Johnson Space Center (JSC), MSFC-HDBK-527/JSC 09604. MAPTIS can be accessed by computer datalink. Systems containing materials that have not

  10. Support Operators Method for the Diffusion Equation in Multiple Materials

    SciTech Connect

    Winters, Andrew R.; Shashkov, Mikhail J.

    2012-08-14

    A second-order finite difference scheme for the solution of the diffusion equation on non-uniform meshes is implemented. The method allows the heat conductivity to be discontinuous. The algorithm is formulated on a one dimensional mesh and is derived using the support operators method. A key component of the derivation is that the discrete analog of the flux operator is constructed to be the negative adjoint of the discrete divergence, in an inner product that is a discrete analog of the continuum inner product. The resultant discrete operators in the fully discretized diffusion equation are symmetric and positive definite. The algorithm is generalized to operate on meshes with cells which have mixed material properties. A mechanism to recover intermediate temperature values in mixed cells using a limited linear reconstruction is introduced. The implementation of the algorithm is verified and the linear reconstruction mechanism is compared to previous results for obtaining new material temperatures.

  11. Additive Manufacturing: Building the Pathway Towards Process and Material Qualification”

    DOE PAGES

    Carpenter, John S.; Beese, Allison M.; Bourell, David L.; ...

    2016-06-14

    The potential benefits of metal additive manufacturing, as compared with more traditional, subtractive-only approaches, has created excitement within design circles seeking to take advantage of the ability to build and repair complex shapes, to integrate or consolidate multiple parts and minimize joining concerns, and to locally tailor material properties to increase functionality. Tempering the excitement of designers, however, has been concerns with the material deposited by the process. It is not enough for a part to ‘look’ right from a geometric perspective. Rather, the metallurgical aspects associated with the material being deposited must ‘look’ and ‘behave’ correctly along with themore » aforementioned geometric accuracy. Finally, without elucidation of the connections between processing, microstructure, properties, and performance from a materials science perspective, metal additive manufacturing will not realize its potential to change the manufacturing world for property and performance-critical engineering applications.« less

  12. Additive Manufacturing: Building the Pathway Towards Process and Material Qualification”

    SciTech Connect

    Carpenter, John S.; Beese, Allison M.; Bourell, David L.; Hamilton, Reginald F.; Herderick, Edward; Mishra, Rajiv S.; Sears, James

    2016-06-14

    The potential benefits of metal additive manufacturing, as compared with more traditional, subtractive-only approaches, has created excitement within design circles seeking to take advantage of the ability to build and repair complex shapes, to integrate or consolidate multiple parts and minimize joining concerns, and to locally tailor material properties to increase functionality. Tempering the excitement of designers, however, has been concerns with the material deposited by the process. It is not enough for a part to ‘look’ right from a geometric perspective. Rather, the metallurgical aspects associated with the material being deposited must ‘look’ and ‘behave’ correctly along with the aforementioned geometric accuracy. Finally, without elucidation of the connections between processing, microstructure, properties, and performance from a materials science perspective, metal additive manufacturing will not realize its potential to change the manufacturing world for property and performance-critical engineering applications.

  13. Using Educative Curriculum Materials to Support Preservice Elementary Teachers' Curricular Planning: A Comparison between Two Different Forms of Support

    ERIC Educational Resources Information Center

    Beyer, Carrie J.; Davis, Elizabeth A.

    2009-01-01

    Educative curriculum materials--materials designed to promote both teacher and student learning--may help novice teachers learn how to engage in productive curricular planning. However, little is known about how educative supports within these materials should be written to best support teachers. This quasi-experimental study examines the…

  14. Additive benefits of autonomy support and enhanced expectancies for motor learning.

    PubMed

    Wulf, Gabriele; Chiviacowsky, Suzete; Cardozo, Priscila Lopes

    2014-10-01

    Two factors that have been shown to facilitate motor learning are autonomy support (AS) and enhanced expectancies (EE) for performance. We examined the individual and combined influences of these factors. In a 2 × 2 design, participants learning a novel motor skill (throwing with the non-dominant arm) were or were not provided a choice (AS) about the ball color on each of 6 10-trial blocks during practice, and were or were not given bogus positive social-comparative feedback (EE). This resulted in four groups: AS/EE, AS, EE, and C (control). One day after the practice phase, participants completed 10 retention and 10 transfer trials. The distance to the target--a bull's eye with a 1m radius and 10 concentric circles--was 7.5m during practice and retention, and 8.5m during transfer. Autonomy support and enhanced expectancies had additive advantages for learning, with both main effects being significant for retention and transfer. On both tests, the AS/EE group showed the greatest throwing accuracy. Also, the accuracy scores of the AS and EE groups were higher than those of the C group. Furthermore, self-efficacy measured after practice and before retention and transfer was increased by both AS and EE. Thus, supporting learners' need for autonomy by given them a small choice--even though it was not directly related to task performance--and enhancing their performance expectancies appeared to independently influence learning.

  15. 16 CFR 803.20 - Requests for additional information or documentary material.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Requests for additional information or documentary material. 803.20 Section 803.20 Commercial Practices FEDERAL TRADE COMMISSION RULES, REGULATIONS, STATEMENTS AND INTERPRETATIONS UNDER THE HART-SCOTT-RODINO ANTITRUST IMPROVEMENTS ACT OF 1976...

  16. 16 CFR 803.20 - Requests for additional information or documentary material.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Requests for additional information or documentary material. 803.20 Section 803.20 Commercial Practices FEDERAL TRADE COMMISSION RULES, REGULATIONS, STATEMENTS AND INTERPRETATIONS UNDER THE HART-SCOTT-RODINO ANTITRUST IMPROVEMENTS ACT OF 1976...

  17. 16 CFR 803.20 - Requests for additional information or documentary material.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Requests for additional information or documentary material. 803.20 Section 803.20 Commercial Practices FEDERAL TRADE COMMISSION RULES, REGULATIONS, STATEMENTS AND INTERPRETATIONS UNDER THE HART-SCOTT-RODINO ANTITRUST IMPROVEMENTS ACT OF 1976...

  18. 16 CFR 803.20 - Requests for additional information or documentary material.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Requests for additional information or documentary material. 803.20 Section 803.20 Commercial Practices FEDERAL TRADE COMMISSION RULES, REGULATIONS, STATEMENTS AND INTERPRETATIONS UNDER THE HART-SCOTT-RODINO ANTITRUST IMPROVEMENTS ACT OF 1976...

  19. Effect of additions of aluminosilicate and silicate materials on the softening temperature of chromite ore

    NASA Astrophysics Data System (ADS)

    Zhdanov, A. V.; Nurmaganbetova, B. N.; Pavlov, V. A.

    2015-07-01

    The temperatures of the beginning and end of softening and the temperature range of softening of the fines of the rich chromite ore of the Donskoy Ore Mining & Processing Plant in Kazakhstan are experimentally determined. The following natural and technical silica-containing materials, which are considered as fluxing additions to decrease the melting temperature of the chromite ore, are investigated: aluminosilicate clays, microsilica, and quartzite of various fractions. The effect of additions of the natural and technical silica-containing materials on the temperatures of the beginning and end of softening and the temperature range of softening of the chromite ore of DODPE is analyzed. The influences of various materials and their fraction compositions on the temperature of softening of the chromite ores are compared.

  20. On the design of novel multifunctional materials by using particulate additives

    NASA Astrophysics Data System (ADS)

    Dunnigan, Ross Daniel

    This thesis has been organized into five chapters. The main focus of this thesis is to design novel multifunctional materials by using particulate additives. Chapter 1 is devoted to reviewing recent studies in additive manufacturing (AM) and other background information. In Chapter 2, the synthesis and characterization of novel Ti3SiC2-reinforced Zn-matrix composites is reported. During this study, all the Zn composites were hot pressed at 500°C for 5 min at a uniaxial pressure of ~150 MPa. Microstructure analysis by SEM (Scanning Electron Microscopy) and phase analysis by XRD (X-ray Diffraction) confirmed that there was minimal interfacial reaction between Ti3SiC 2 particles and the Zn matrix. The addition of Ti3SiC 2 improved the tribological performance of these composites against alumina substrates but did not have any beneficial effect on the mechanical performance. The addition of Ti3SiC2 particulates to metal and polymer matrices show interesting properties. Chapter 3 will focus on additive manufacturing of Ti3SiC2 particulates in a polymer matrix. Waste materials are a big problem in the world. Chapters 4 and 5 focus on recycling materials. The mechanical and tribological properties of the Resin-Nylon and ResinPolyester composites are reported, respectively.

  1. Influence of molybdenum silicide additions on high-temperature oxidation resistance of silicon nitride materials

    SciTech Connect

    Klemm, H.; Tangermann, K.; Schubert, C.; Hermel, W.

    1996-09-01

    The influence of additions of molybdenum disilicide (MoSi{sub 2}) on the microstructure and the mechanical properties of a silicon nitride (Si{sub 3}N{sub 4}) material, with neodymium oxide (Nd{sub 2}O{sub 3}) and aluminum nitride (AlN) as sintering aids, was studied. The composites, containing 5, 10, and 17.6 wt% MoSi{sub 2}, were fabricated by hot pressing. All materials exhibited a similar phase composition, detected by X-ray diffractometry. Up to MoSi{sub 2} additions of 10 wt%, mechanical properties such as strength, fracture toughness, or creep at 1,400 C were not affected significantly, in comparison to that of monolithic Si{sub 3}N{sub 4}. The oxidation resistance of the composites, in terms of weight gain, degraded. After 1,000 h of oxidation at 1,400 and 1,450 C in air, a greater weight gain (by a factor of approximately three) was obtained, in comparison to that of the material without MoSi{sub 2}. Nevertheless, after 1,000 h of oxidation, the degradation in strength of the composites was considerably less severe than that of the material without MoSi{sub 2}. An additional layer was formed, caused by processes at the surface of the Si{sub 3}N{sub 4} material, preventing the formation of pores, cracks, or glassy-phase-rich areas, which are common features of oxidation damage in Si{sub 3}N{sub 4} materials. This surface layer, containing Mo{sub 5}Si{sub 3} and silicon oxynitride (Si{sub 2}ON{sub 2}), was the result of reactions between MoSi{sub 2}, Si{sub 3}N{sub 4}, and the oxygen penetrating by diffusion into the material during the high-temperature treatment.

  2. Effect of vermicomposting on concentration and speciation of heavy metals in sewage sludge with additive materials.

    PubMed

    He, Xin; Zhang, Yaxin; Shen, Maocai; Zeng, Guangming; Zhou, Mucen; Li, Meirong

    2016-10-01

    The aim of this work was to evaluate the total content and speciation of heavy metals (As, Cr, Cd, Cu, Fe, Mn, Ni, Pb and Zn) during vermicomposting of sewage sludge by Eisenia fetida earthworm with different additive materials (soil, straw, fly ash and sawdust). Results showed that the pH, total organic carbon were reduced, while the electric conductivity and germination index increased after a combined composting - vermicomposting process. The addition of bulking agents accelerated the stabilization of sludge and eliminated its toxicity. The total heavy metals after vermicomposting in 10 scenarios were lowered as compared with the initial values and the control without amendment. BCR sequential extraction indicated that vermicomposting significantly decreased the mobility of all heavy metals by increasing the residual fractions. The activity of earthworms and appropriate addition of amendment materials played a positive role in sequestering heavy metals during the treatment of sewage sludge.

  3. New water-soluble metal working fluids additives from phosphonic acid derivatives for aluminum alloy materials.

    PubMed

    Kohara, Ichitaro; Tomoda, Hideyuki; Watanabe, Shoji

    2007-01-01

    Water-soluble metal working fluids are used for processing of aluminum alloy materials. This short paper describes properties of new additives for water-soluble cutting fluids for aluminum alloy materials. Some alkyldiphosphonic acids were prepared with known method. Amine salts of these phosphonic acids showed anti-corrosion property for aluminum alloy materials. However, they have no hard water tolerance. Monoesters of octylphosphonic acid were prepared by the reaction of octylphosphonic acid dichloride with various alcohols in the presence of triethylamine. Amine salts of monoester of octylphosphonic acid with diethyleneglycol monomethyl ether, ethyleneglycol monomethyl ether and triethyleneglycol monomethyl ether showed both of a good anti-corrosion property for aluminum alloy materials and hard water tolerance.

  4. Computed Tomography Support for Microgravity Materials Science Experiments

    NASA Technical Reports Server (NTRS)

    Gillies, Donald C.; Engel, H. Peter; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    The accurate measurement of density in both liquid and solid samples is of considerable interest to Principal Investigators with materials science experiments slated for the ISS. The work to be described is an innovative application of a conventional industrial nondestructive evaluation instrument. Traditional applications of industrial computed tomography (CT) rely on reconstructing cross sections of large structures to provide two-dimensional planar views which can identify defects such as porosity, or other material anomalies. This has been done on microgravity materials science experiments to check the integrity of ampoule-cartridge assemblies for safety purposes. With a substantially monoenergetic flux, as can be obtained with a radioactive cobalt source, there will be a direct correlation between absorption and density. Under such conditions it then becomes possible to make accurate measurements of density throughout a sample, and even when the sample itself is enclosed within a furnace and a safety required cartridge. Such a system has been installed at Kennedy Space Center (KSC) and is available to PIs to examine samples before and after flight. The CT system is being used to provide density information for two purposes. Firstly, the determination of density changes from liquid to solid is vital information to the PI for purposes of modeling the solidification behavior of his sample, and to engineers who have to design containment ampoules and must allow for shrinkage and other volume changes that may occur during processing. While such information can be obtained by pycnometric measurements, the possibility of using a furnace installed on the CT system enables one to examine potentially dangerous materials having high vapor pressures, while not needing visible access to the material. In addition, uniform temperature can readily be obtained, and the system can be controlled to ramp up, hold, and ramp down while collecting data over a wide range of

  5. An additive approach to low temperature zero pressure sintering of bismuth antimony telluride thermoelectric materials

    NASA Astrophysics Data System (ADS)

    Catlin, Glenn C.; Tripathi, Rajesh; Nunes, Geoffrey; Lynch, Philip B.; Jones, Howard D.; Schmitt, Devin C.

    2017-03-01

    This paper presents an additive-based approach to the formulation of thermoelectric materials suitable for screen printing. Such printing processes are a likely route to such thermoelectric applications as micro-generators for wireless sensor networks and medical devices, but require the development of materials that can be sintered at ambient pressure and low temperatures. Using a rapid screening process, we identify the eutectic combination of antimony and tellurium as an additive for bismuth-antimony-telluride that enables good thermoelectric performance without a high pressure step. An optimized composite of 15 weight percent Sb7.5Te92.5 in Bi0.5Sb1.5Te3 is scaled up and formulated into a screen-printable paste. Samples fabricated from this paste achieve a thermoelectric figure of merit (ZT) of 0.74 using a maximum processing temperature of 748 K and a total thermal processing budget of 12 K-hours.

  6. Functionalized 3D Architected Materials via Thiol-Michael Addition and Two-Photon Lithography.

    PubMed

    Yee, Daryl W; Schulz, Michael D; Grubbs, Robert H; Greer, Julia R

    2017-02-20

    Fabrication of functionalized 3D architected materials is achieved by a facile method using functionalized acrylates synthesized via thiol-Michael addition, which are then polymerized using two-photon lithography. A wide variety of functional groups can be attached, from Boc-protected amines to fluoroalkanes. Modification of surface wetting properties and conjugation with fluorescent tags are demonstrated to highlight the potential applications of this technique.

  7. Controlling the Electrostatic Discharge Ignition Sensitivity of Composite Energetic Materials Using Carbon Nanotube Additives

    DTIC Science & Technology

    2014-08-10

    Michelle L. Pantoya, Michael A. Daniels Se. TASK NUMBER Sf. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAMES AND ADDRESSES 8. PERFORMING ORGANIZATION...of composite energetic materials using carbon nanotube additives Kade H. Poper a, Eric S. Collins a, Michelle L. Pantoya a, *, Michael A. Daniels b a...Thermochim. Acta 451 (1 2) (2006). [2] Chelsea Weir, Michelle L. Pantoya, Michael Daniels , Electrostatic discharge sensitivity and electrical conductivity

  8. Material Development for Tooling Applications Using Big Area Additive Manufacturing (BAAM)

    SciTech Connect

    Duty, Chad E.; Drye, Tom; Franc, Alan

    2015-03-01

    Techmer Engineered Solutions (TES) is working with Oak Ridge National Laboratory (ORNL) to develop materials and evaluate their use for ORNL s recently developed Big Area Additive Manufacturing (BAAM) system for tooling applications. The first phase of the project established the performance of some commercially available polymer compositions deposited with the BAAM system. Carbon fiber reinforced ABS demonstrated a tensile strength of nearly 10 ksi, which is sufficient for a number of low temperature tooling applications.

  9. A comparison of dimensional accuracy between three different addition cured silicone impression materials.

    PubMed

    Forrester-Baker, L; Seymour, K G; Samarawickrama, D; Zou, L; Cherukara, G; Patel, M

    2005-06-01

    Ten impressions of a metal implant abutment were made with each of three addition-cured silicone impression materials. Using the technique of co-ordinate metrology, the shoulder region of the abutment and corresponding regions of both impressions and dies made from these impressions were scanned and measured. Comparison of these measurements indicated that the mean dimension measured from the shoulder region for each group of impression materials was significantly different from those taken from the original metal implant abutment. However, when these impressions were cast in a gypsum based die material, none of the measured dimensions taken from the casts were significantly different from those taken from the original metal implant abutment. Thus, any change in measured dimensions occurring during impression making, was compensated for in some way by the casting process.

  10. Aging effects on fire-retardant additives in organic materials for nuclear-plant applications

    SciTech Connect

    Clough, R.L.

    1982-08-01

    Inhibiting fire is a major concern of nuclear safety. One of the most widely used commercial fire-retardant additives incorporated into cable insulation and other organic materials to reduce their flammability has been the halocarbon (usually a chlorinated hydrocarbon), typically in combination with antimony oxide. Such materials may be installed for the design lifetime of a nuclear plant; this report describes an investigation of the long-term aging behavior of these fire-retardant additives in polymeric materials. Extensive aging experiments on fire-retarded formulations of ethylene propylene rubber (EPR) and of chlorosulfonated polyethylene (CSPE) have been carried out, with chemical analysis of halogen and antimony content performed as a function of aging time and conditions. Oxygen index flammability measurements were also performed on selected samples. Significant fire-retardant losses (both chlorine (Cl) and antimony (Sb)) were found to occur in certain of the fire-retardant materials but not in others, depending on the molecular structure of the particular halogen-containing component. The data indicate that the loss of halogen- and antimony-based fire retardants appears to be insignificant under ambient conditions expected for nuclear plants.

  11. Additional material of the enigmatic Early Miocene mammal Kelba and its relationship to the order Ptolemaiida

    PubMed Central

    Cote, Susanne; Werdelin, Lars; Seiffert, Erik R.; Barry, John C.

    2007-01-01

    Kelba quadeemae, a fossil mammal from the Early Miocene of East Africa, was originally named on the basis of three isolated upper molars. Kelba has previously been interpreted as a creodont, a pantolestid, an insectivoran, and a hemigaline viverrid. The true affinities of this taxon have remained unclear because of the limited material and its unique morphology relative to other Miocene African mammals. New material of Kelba from several East African Miocene localities, most notably a skull from the Early Miocene locality of Songhor in Western Kenya, permits analysis of the affinities of Kelba and documents the lower dentition of this taxon. Morphological comparison of this new material clearly demonstrates that Kelba is a member of the order Ptolemaiida, a poorly understood group whose fossil record was previously restricted to the Oligocene Fayum deposits of northern Egypt. Phylogenetic analysis supports the monophyly of the Ptolemaiida, including Kelba, and recovers two monophyletic clades within the order. We provide new family names for these groups and an emended diagnosis for the order. The discovery of ptolemaiidans from the Miocene of East Africa is significant because it extends the known temporal range of the order by >10 million years and the geographic range by >3,200 km. Although the higher-level affinities of the Ptolemaiida remain obscure, their unique morphology and distribution through a larger area of Africa (and exclusively Africa) lend support to the idea that Ptolemaiida may have an ancient African origin. PMID:17372202

  12. Porous hollow carbon spheres for electrode material of supercapacitors and support material of dendritic Pt electrocatalyst

    NASA Astrophysics Data System (ADS)

    Fan, Yang; Liu, Pei-Fang; Huang, Zhong-Yuan; Jiang, Tong-Wu; Yao, Kai-Li; Han, Ran

    2015-04-01

    Porous hollow carbon spheres (PHCSs) are prepared through hydrothermal carbonization of alginic acid and subsequent chemical activation by KOH. The porosity of the alginic acid derived PHCSs can be finely modulated by varying activation temperature in the range of 600-900 °C. The PHCSs activated at 900 °C possess the largest specific surface area (2421 m2 g-1), well-balanced micro- and mesoporosity, as well as high content of oxygen-containing functional groups. As the electrode material for supercapacitors, the PHCSs exhibit superior capacitive performance with specific capacitance of 314 F g-1 at current density of 1 A g-1. Pt nanodendrites supported on the PHCSs are synthesized by polyol reduction method which exhibit high electrocatalytic activity towards methanol oxidation reaction (MOR). Moreover, CO-poisoning tolerance of the Pt nanodendrites is greatly enhanced owing to the surface chemical property of the PHCSs support.

  13. Effect of halide and acid additives on the direct synthesis of hydrogen peroxide using supported gold-palladium catalysts.

    PubMed

    Ntainjua N, Edwin; Piccinini, Marco; Pritchard, James C; Edwards, Jennifer K; Carley, Albert F; Moulijn, Jacob A; Hutchings, Graham J

    2009-01-01

    The effect of halide and acid addition on the direct synthesis of hydrogen peroxide is studied for magnesium oxide- and carbon-supported bimetallic gold-palladium catalysts. The addition of acids decreases the hydrogenation/decomposition of hydrogen peroxide, and the effect is particularly pronounced for the magnesium oxide-supported catalysts whilst for carbon-supported catalysts the pH requires close control to optimize hydrogen peroxide synthesis. The addition of bromide leads to a marked decrease in the hydrogenation/decomposition of hydrogen peroxide with either catalyst. These effects are discussed in terms of the structure of the gold-palladium alloy nanoparticles and the isoelectric point of the support. We conclude that with the highly active carbon-supported gold-palladium catalysts these additives are not required and that therefore this system presents the potential for the direct synthesis of hydrogen peroxide to be operated using green process technology.

  14. Role of Additives in Composite PEI/Oxide CO₂ Adsorbents: Enhancement in the Amine Efficiency of Supported PEI by PEG in CO₂ Capture from Simulated Ambient Air.

    PubMed

    Sakwa-Novak, Miles A; Tan, Shuai; Jones, Christopher W

    2015-11-11

    Supported amines are promising candidate adsorbents for the removal of CO2 from flue gases and directly from ambient air. The incorporation of additives into polymeric amines such as poly(ethylenimine) (PEI) supported on mesoporous oxides is an effective strategy to improve the performance of the materials. Here, several practical aspects of this strategy are addressed with regards to direct air capture. The influence of three additives (CTAB, PEG200, PEG1000) was systematically explored under dry simulated air capture conditions (400 ppm of CO2, 30 °C). With SBA-15 as a model support for poly(ethylenimine) (PEI), the nature of the additive induced heterogeneities in the deposition of organic on the interior and exterior of the particles, an important consideration for future scale up to practical systems. The PEG200 additive increased the observed thermodynamic performance (∼60% increase in amine efficiency) of the adsorbents regardless of the PEI content, while the other molecules had less positive effects. A threshold PEG200/PEI value was identified at which the diffusional limitations of CO2 within the materials were nearly eliminated. The threshold PEG/PEI ratio may have physical origin in the interactions between PEI and PEG, as the optimal ratio corresponded to nearly equimolar OH/reactive (1°, 2°) amine ratios. The strategy is shown to be robust to the characteristics of the host support, as PEG200 improved the amine efficiency of PEI when supported on two varieties of mesoporous γ-alumina with PEI.

  15. Laser-shocked energetic materials with metal additives: evaluation of detonation performance

    NASA Astrophysics Data System (ADS)

    Gottfried, Jennifer; Bukowski, Eric

    A focused, nanosecond-pulsed laser with sufficient energy to exceed the breakdown threshold of a material generates a laser-induced plasma with high peak temperatures, pressures, and shock velocities. Depending on the laser parameters and material properties, nanograms to micrograms of material is ablated, atomized, ionized and excited in the laser-induced plasma. The subsequent shock wave expansion into the air above the sample has been monitored using high-speed schlieren imaging in a recently developed technique, laser-induced air shock from energetic materials (LASEM). The estimated detonation velocities using LASEM agree well with published experimental values. A comparison of the measured shock velocities for various energetic materials including RDX, DNTF, and LLM-172 doped with Al or B to the detonation velocities predicted by CHEETAH for inert or active metal participation demonstrates that LASEM has potential for predicting the early time participation of metal additives in detonation events. The LASEM results show that reducing the amount of hydrogen present in B formulations increases the resulting detonation velocities

  16. Application of polymer graded-index materials for aberration correction of progressive addition lenses

    NASA Astrophysics Data System (ADS)

    Shitanoki, Yuki; Tagaya, Akihiro; Koike, Yasuhiro

    2009-02-01

    Graded-index (GRIN) progressive addition lens (PAL) was successfully fabricated, and GRIN's potential for aberration correction of PAL was confirmed. GRIN material was prepared by partial diffusion of methyl methacrylate (MMA (nd at polymer = 1.492)) monomer into cross-linked benzyl methacrylate (BzMA (nd at polymer=1.568)) flat gel, and GRINPAL was prepared by polymerization of the GRIN material attached to a mold of commercially available PAL. GRIN polymer materials have been used for various applications such as rod lenses and optical fibers. GRIN represents gradual change of refractive index in a material, which adds or reduces light focusing power of the material. PAL is a multifocal spectacle lens for presbyopia. However, some localized aberrations (especially astigmatism) in PAL have not yet been reduced satisfactorily for decades by optimizing surface geometry of a lens. In this research, we propose to employ GRIN materials for astigmatism reduction of PALs. BzMA flat gel was prepared by UV polymerization of BzMA, crosslinking agent ethylene glycol dimethacrylate (EDMA) and photopolymerization initiator DAROCURE 1173. MMA monomer was diffused into BzMA flat gel from a portion of periphery for several hours. The obtained GRIN material was attached to a mold of commercially available PAL and polymerized by UV. As a result, reduction of astigmatism was confirmed locally in the fabricated PAL and GRIN-PAL using lens meter. In conclusion, GRIN-PAL was successfully fabricated. The validity of GRIN employment for the astigmatism reduction in PAL was demonstrated experimentally.

  17. Gold nanocatalysts supported on heterostructured PbSO4-MCF mesoporous materials for CO oxidation

    SciTech Connect

    Li, Lin; Tian, Chengcheng; Chai, Songhai; Binder, Andrew J; Brown, Suree; Veith, Gabriel M; Dai, Sheng

    2014-01-01

    Metal oxides are commonly used as the supports of gold nanoparticles for catalytic CO oxidation, whereas metal salts are rarely considered suitable supports. In the present work, we developed a new kind of gold nanocatalyst supported on heterostructured PbSO4-MCF mesoporous materials that was prepared by an in situ growth method using dodecylbenzenesulfonate (SOBS) as a sulfonate precursor. It was found that an Au/PbSO4-MCF (SDBS) catalyst preheated at 300 degrees C showed high CO conversion below 100 degrees C. In addition, the stability of selected catalysts was studied as a function of time on stream. Because of the alteration of surface properties, these Au nanocatalysts were highly sinter-resistant. Published by Elsevier B.V.

  18. Flexible Foam Protection Materials for Constellation Space Suit Element Portable Life Support Subsystem Packaging Study

    NASA Technical Reports Server (NTRS)

    Tang, Henry H.; Orndoff, Evelyne S.; Thomas, Gretchen A.

    2009-01-01

    This paper discusses the effort in evaluating and selecting a light weight impact protection material for the Constellation Space Suit Element (CSSE) Portable Life Support Subsystem (PLSS) conceptual packaging study. A light weight material capable of holding and protecting the components inside the PLSS is required to demonstrate the viability of the flexible PLSS packaging concept. The material needs to distribute, dissipate, and absorb the impact energy of the PLSS falling on the lunar surface. It must also be very robust and function in the extreme lunar thermal vacuum environment for up to one hundred Extravehicular Activity (EVA) missions. This paper documents the performance requirements for selecting a foam protection material, and the methodologies for evaluating commercial off-the-shelf (COTS) foam protection materials. It also presents the materials properties test results and impact drop test results of the various foam materials evaluated in the study. The findings from this study suggest that a foam based flexible protection system is a viable solution for PLSS packaging. However, additional works are needed to optimize COTS foam properties or to develop a composite foam system that will meet all the performance requirements for the CSSE PLSS flexible packaging.

  19. Determination of additives in PVC material by UV laser ablation inductively coupled plasma atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Hemmerlin, M.; Mermet, J. M.; Bertucci, M.; Zydowicz, P.

    1997-04-01

    UV laser ablation inductively coupled plasma atomic emission spectrometry (LA-ICP-AES) has been applied to the direct determination of additives in solid poly(vinyl chloride) materials. A Nd:YAG laser, operating at its fourth harmonic (266 nm), was used with a beam masking device, in the most reproducible conditions, to introduce solid particles into the plasma torch of a simultaneous ICP-AES system. Emphasis was placed on both precision and accuracy in the analysis of PVC materials by LA-ICP-AES. A series of six in-house PVC reference materials was prepared by incorporating several additives in increasing concentrations. Three alternative methods were evaluated to certify the amount of incorporated elements: ICP-AES with sample dissolution, NAA and XRF. Satisfactory results and good agreement were obtained for seven elements (Al, Ca, Cd, Mg, Sb, Sn and Ti) among the ten incorporated. Sample homogeneity appeared to be satisfactory, and calibration graphs obtained by LA-ICP-AES for several elements are presented. Finally, the performance of the technique in terms of repeatability (1.6-5%), reproducibility (2-5%), and limits of detection was investigated.

  20. Supported Intrinsically Porous Oligomers as Hybrid Materials for Separations, Storage, and Sensing

    NASA Astrophysics Data System (ADS)

    Thompson, Anthony Boone

    Adsorption-desorption phenomena are often difficult to study at the molecular level because the surfaces on which they occur can be heterogeneous, giving a wide distribution of adsorption sites and associated energies. Considering that these phenomena underlie an incredibly wide variety of industrially important processes, a better understanding could aid in the development of more efficient methods. In this work, we describe an approach to designing materials with well-defined adsorption sites by covalently attaching intrinsically porous molecules to solid surfaces by a rigid multidentate linker. These cup-shaped molecules are intended to act as adsorption sites on the material, whereas the rigid attachment to the solid support serves to prevent movement and conformational changes of the sites, leading to better understanding of adsorption phenomena. As a proof-of-concept application, materials were used for adsorption of n-butanol biofuel and related compounds from dilute aqueous solution. The materials were thermally and hydrolytically stable, and adsorption phenomena were reversible. Adsorption sites containing more hydrophobic molecular area led to stronger adsorption, suggesting that it is driven by weak van der Waals forces. Likewise, adsorption sites that were strongly polarized performed poorly, possibly reflecting a greater energy penalty of removing water molecules from the cavity. Upon placing a Lewis acidic metal at the bottom of the cavity, an enhancement was seen only with the most acidic metal, which may indicate weak guest coordination. Observing that hydrophobic interactions dominate adsorption on these materials, efforts were made to develop hybrid materials with large hydrophobic area for adsorption. Glaser coupling of diethynylbenzene was used to grow oligo(phenylene butadiynylene)s from the surface of silica, resulting in materials that were more than 25% organic by weight. In addition to their potential use as adsorbents, these materials may

  1. Development of Additive Construction Technologies for Application to Development of Lunar/Martian Surface Structures Using In-Situ Materials

    NASA Technical Reports Server (NTRS)

    Werkheiser, Niki J.; Fiske, Michael R.; Edmunson, Jennifer E.; Khoshnevis, Berokh

    2015-01-01

    For long-duration missions on other planetary bodies, the use of in situ materials will become increasingly critical. As human presence on these bodies expands, so must the breadth of the structures required to accommodate them including habitats, laboratories, berms, radiation shielding for natural radiation and surface reactors, garages, solar storm shelters, greenhouses, etc. Planetary surface structure manufacturing and assembly technologies that incorporate in situ resources provide options for autonomous, affordable, pre-positioned environments with radiation shielding features and protection from micrometeorites, exhaust plume debris, and other hazards. The ability to use in-situ materials to construct these structures will provide a benefit in the reduction of up-mass that would otherwise make long-term Moon or Mars structures cost prohibitive. The ability to fabricate structures in situ brings with it the ability to repair these structures, which allows for the self-sufficiency and sustainability necessary for long-duration habitation. Previously, under the auspices of the MSFC In-Situ Fabrication and Repair (ISFR) project and more recently, under the jointly-managed MSFC/KSC Additive Construction with Mobile Emplacement (ACME) project, the MSFC Surface Structures Group has been developing materials and construction technologies to support future planetary habitats with in-situ resources. One such additive construction technology is known as Contour Crafting. This paper presents the results to date of these efforts, including development of novel nozzle concepts for advanced layer deposition using this process. Conceived initially for rapid development of cementitious structures on Earth, it also lends itself exceptionally well to the automated fabrication of planetary surface structures using minimally processed regolith as aggregate, and binders developed from in situ materials as well. This process has been used successfully in the fabrication of

  2. Evaluation of critical materials in five additional advance design photovoltaic cells

    SciTech Connect

    Smith, S.A.; Watts, R.L.; Martin, P.; Gurwell, W.E.

    1981-02-01

    The objective of this study is to identify potential material supply constraints due to the large-scale deployment of five advanced photovoltaic (PV) cell designs, and to suggest strategies to reduce the impacts of these production capacity limitations and potential future material shortages. The Critical Materials Assessment Program (CMAP) screens the designs and their supply chains and identifies potential shortages which might preclude large-scale use of the technologies. The results of the screening of five advanced PV cell designs are presented: (1) indium phosphide/cadmium sulfide, (2) zinc phosphide, (3) cadmium telluride/cadmium sulfide, (4) copper indium selenium, and (5) cadmium selenide photoelectrochemical. Each of these five cells is screened individually assuming that they first come online in 1991, and that 25 Gwe of peak capacity is online by the year 2000. A second computer screening assumes that each cell first comes online in 1991 and that each cell has a 5 GWe of peak capacity by the year 2000, so that the total online capacity for the five cells is 25 GWe. Based on a review of the preliminary baseline screening results, suggestions were made for varying such parameters as the layer thickness, cell production processes, etc. The resulting PV cell characterizations were then screened again by the CMAP computer code. The CMAP methodology used to identify critical materials is described; and detailed characterizations of the advanced photovoltaic cell designs under investigation, descriptions of additional cell production processes, and the results are presented. (WHK)

  3. Active metal-matrix composites with embedded smart materials by ultrasonic additive manufacturing

    NASA Astrophysics Data System (ADS)

    Hahnlen, Ryan; Dapino, Marcelo J.

    2010-04-01

    This paper presents the development of active aluminum-matrix composites manufactured by Ultrasonic Additive Manufacturing (UAM), an emerging rapid prototyping process based on ultrasonic metal welding. Composites created through this process experience temperatures as low as 25 °C during fabrication, in contrast to current metal-matrix fabrication processes which require temperatures of 500 °C and above. UAM thus provides unprecedented opportunities to develop adaptive structures with seamlessly embedded smart materials and electronic components without degrading the properties that make these materials and components attractive. This research focuses on developing UAM composites with aluminum matrices and embedded shape memory NiTi, magnetostrictive Galfenol, and electroactive PVDF phases. The research on these composites will focus on: (i) electrical insulation between NiTi and Al phases for strain sensors, investigation and modeling of NiTi-Al composites as tunable stiffness materials and thermally invariant structures based on the shape memory effect; (ii) process development and composite testing for Galfenol-Al composites; and (iii) development of PVDF-Al composites for embedded sensing applications. We demonstrate a method to electrically insulate embedded materials from the UAM matrix, the ability create composites containing up to 22.3% NiTi, and their resulting dimensional stability and thermal actuation characteristics. Also demonstrated is Galfenol-Al composite magnetic actuation of up to 54 μ(see manuscript), and creation of a PVDF-Al composite sensor.

  4. Novel Overhang Support Designs for Powder-Based Electron Beam Additive Manufacturing (EBAM)

    NASA Technical Reports Server (NTRS)

    Nabors, Sammy A.

    2014-01-01

    NASA Marshall Space Flight Center, in collaboration with the University of Alabama, has developed a contact-free support structure used to fabricate overhang-type geometries via EBAM. The support structure is used for 3-D metal-printed components for the aerospace, automotive, biomedical and other industries. Current techniques use support structures to address deformation challenges inherent in 3-D metal printing. However, these structures (overhangs) are bonded to the component and need to be removed in post-processing using a mechanical tool. This new technology improves the overhang support structure design for components by eliminating associated geometric defects and post-processing requirements.

  5. Processing of New Materials by Additive Manufacturing: Iron-Based Alloys Containing Silver for Biomedical Applications

    NASA Astrophysics Data System (ADS)

    Niendorf, Thomas; Brenne, Florian; Hoyer, Peter; Schwarze, Dieter; Schaper, Mirko; Grothe, Richard; Wiesener, Markus; Grundmeier, Guido; Maier, Hans Jürgen

    2015-07-01

    In the biomedical sector, production of bioresorbable implants remains challenging due to improper dissolution rates or deficient strength of many candidate alloys. Promising materials for overcoming the prevalent drawbacks are iron-based alloys containing silver. However, due to immiscibility of iron and silver these alloys cannot be manufactured based on conventional processing routes. In this study, iron-manganese-silver alloys were for the first time synthesized by means of additive manufacturing. Based on combined mechanical, microscopic, and electrochemical studies, it is shown that silver particles well distributed in the matrix can be obtained, leading to cathodic sites in the composite material. Eventually, this results in an increased dissolution rate of the alloy. Stress-strain curves showed that the incorporation of silver barely affects the mechanical properties.

  6. How Good Are We at Implementing the Additional Support for Learning Act? How Good Can We Be?

    ERIC Educational Resources Information Center

    Her Majesty's Inspectorate of Education, 2007

    2007-01-01

    This brief publication provides bullet points of what education authorities are doing well and how they can do better in the following areas: (1) Planning for implementation; (2) Transition arrangements; (3) Meeting additional support needs; (4) Resolving disagreements; (5) Coordinated support plans; and (6) Working with children and young…

  7. Multi-material additive manufacturing of robot components with integrated sensor arrays

    NASA Astrophysics Data System (ADS)

    Saari, Matt; Cox, Bryan; Galla, Matt; Krueger, Paul S.; Richer, Edmond; Cohen, Adam L.

    2015-06-01

    Fabricating a robotic component comprising 100s of distributed, connected sensors can be very difficult with current approaches. To address these challenges, we are developing a novel additive manufacturing technology to enable the integrated fabrication of robotic structural elements with distributed, interconnected sensors and actuators. The focus is on resistive and capacitive sensors and electromagnetic actuators, though others are anticipated. Anticipated applications beyond robotics include advanced prosthetics, wearable electronics, and defense electronics. This paper presents preliminary results for printing polymers and conductive material simultaneously to form small sensor arrays. Approaches to optimizing sensor performance are discussed.

  8. Preliminary result on the enhancement of Ufer electrodes using recycle additives materials

    NASA Astrophysics Data System (ADS)

    Zulkifli, Muhammad Haziq Aniq Bin; Ahmad, Hussein Bin

    2016-11-01

    Ground building pillars is to be used as ground rod. The pillars are design, fabricated, and formulated with new ground fillers. The additives will be used from recycle waste materials mainly from the palm oil plant process. Micro scale building pillars will be fabricated and install in the test ground at all of the location. Earth tester meter are used to measure and collect the data of the soil resistivity when the research is conducted. In collecting these data, 3-terminal methods are used to carry the measurements. This experiment will be conducted for 30 weeks and regular measurements at the test ground copper grids will be conducted to measure the ground electrode resistance. The study will mainly base on IEC 62503-3. The used of reinforcing rods and mixture of recycle additives could produce a better grounding system that are suitable and can be used in all kind of soil condition and large industries.

  9. Flexible Foam Protection Materials for Portable Life Support System Packaging Study

    NASA Technical Reports Server (NTRS)

    Tang,Henry H.; Dillon, Paul A.; Thomas, Gretchen A.

    2009-01-01

    This paper discusses the phase I effort in evaluating and selecting a light weight impact protection material for the Constellation Space Suit Element (CSSE) Portable Life Support System (PLSS) conceptual packaging study. A light weight material capable of holding and protecting the components inside the PLSS is required to demonstrate the viability of the flexible PLSS packaging concept. The material needs to distribute, dissipate, and absorb the impact energy of the PLSS falling on the lunar surface. It must also be robust to consistently perform over several Extravehicular Activity (EVA) missions in the extreme lunar thermal vacuum environment. This paper documents the performance requirements for selecting a foam protection material, and the methodologies for evaluating some commercial off-the-shelf (COTS) foam material candidates. It also presents the mechanical properties and impact drop tests results of the foam material candidates. The results of this study suggest that a foam based flexible protection system is a viable solution for PLSS packaging. However, additional works are needed to optimize COTS foam or to develop a composite foam system that will meet all the performance requirements for the CSSE PLSS flexible packaging.

  10. Research on the additives to reduce radioactive pollutants in the building materials containing fly ash.

    PubMed

    He, Deng-liang; Yin, Guang-fu; Dong, Fa-qin; Liu, Lai-bao; Luo, Ya-jun

    2010-05-15

    Several kinds of functional additives such as barite, zeolite, ferric oxide, gypsum, and high alumina cement were introduced to prepare a low-radiation cement-based composite to reduce radioactive pollutants contained in fly ash. The effect of content and granularity of the functional additives on the release of radioactive pollutants were investigated. Composites were characterized by X-ray diffraction, Scan electron microscopy. The results indicate that the radioactive pollutants contained in the fly ash can be reduced by adding a proper amount of zeolite, ferric oxide, gypsum, and high alumina cement. The release of radon from fly ash decreases with a decrease in the granularity of additives. Compared with traditional cement-based composite containing fly ash, the release of radon can be reduced 64.8% in these composites, and the release of gamma-ray is decreased 45%. Based on the microstructure and phase analysis, we think that by added functional additives, there are favorable to form self-absorption of radioactivity in the interior composites. This cement-based composite will conducive to fly ash are large-scale applied in the field of building materials.

  11. Carbon materials as additives to WO3 for an enhanced conversion of simulated solar light

    NASA Astrophysics Data System (ADS)

    Carmona, Rocío; Velasco, Leticia; Laurenti, Enzo; Maurino, Valter; Ania, Conchi

    2016-02-01

    We have explored the impact of the incorporation of nanoporous carbons as additives to tungsten oxide on the photocatalytic degradation of two recalcitrant pollutants: rhodamine B and phenol, under simulated solar light. For this purpose, WO3/carbon mixtures were prepared using three carbon materials with different properties (in terms of porosity, structural order and surface chemistry). Despite the low carbon content used (2 wt. %), a significant increase in the photocatalytic performance of the semiconductor was observed for all the catalysts. Moreover, the influence of the carbon additive on the performance of the photocatalysts was found to be very different for the two pollutants. Carbon additives of hydrophobic nature increased the photodegradation yield of phenol compared to bare WO3, likely due to the higher affinity and stronger interactions of phenol molecules towards basic nanoporous carbons. Oppositely, the use of acidic carbon additives led to higher rhodamine B conversions due to increased acidity of the WO3/carbon mixtures and the stronger affinity of the pollutant for acidic catalyst’s surfaces. As a result, the photooxidation of rhodamine B is favored by means of a coupled (photosensitized and photocatalytic) degradation mechanism. All these results highlight the importance of favoring the interactions of the pollutant with the catalyst’s surface through a detailed design of the features of the photocatalyst.

  12. Support the Common Core with the Right Instructional Materials

    ERIC Educational Resources Information Center

    Leifer, Rachel; Udall, Denis

    2014-01-01

    Strong instructional materials are crucial to realizing the promise of the Common Core State Standards. Research suggests that the choice of instructional materials can have an impact as large as or larger than the impact of teacher quality. Unfortunately, many popular textbooks are not aligned to the new standards, leaving educators scrambling.…

  13. The work of the European Union Reference Laboratory for Food Additives (EURL) and its support for the authorisation process of feed additives in the European Union: a review

    PubMed Central

    von Holst, Christoph; Robouch, Piotr; Bellorini, Stefano; de la Huebra, María José González; Ezerskis, Zigmas

    2016-01-01

    ABSTRACT This paper describes the operation of the European Union Reference Laboratory for Feed Additives (EURL) and its role in the authorisation procedure of feed additives in the European Union. Feed additives are authorised according to Regulation (EC) No. 1831/2003, which introduced a completely revised authorisation procedure and also established the EURL. The regulations authorising feed additives contain conditions of use such as legal limits of the feed additives, which require the availability of a suitable method of analysis for official control purposes under real world conditions. It is the task of the EURL to evaluate the suitability of analytical methods as proposed by the industry for this purpose. Moreover, the paper shows that one of the major challenges is the huge variety of the methodology applied in feed additive analysis, thus requiring expertise in quite different analytical areas. In order to cope with this challenge, the EURL is supported by a network of national reference laboratories (NRLs) and only the merged knowledge of all NRLs allows for a scientifically sound assessment of the analytical methods. PMID:26540604

  14. Laser-shocked energetic materials with metal additives: evaluation of chemistry and detonation performance.

    PubMed

    Gottfried, Jennifer L; Bukowski, Eric J

    2017-01-20

    A focused, nanosecond-pulsed laser has been used to ablate, atomize, ionize, and excite milligram quantities of metal-doped energetic materials that undergo exothermic reactions in the laser-induced plasma. The subsequent shock wave expansion in the air above the sample has been monitored using high-speed schlieren imaging in a recently developed technique, laser-induced air shock from energetic materials (LASEM). The method enables the estimation of detonation velocities based on the measured laser-induced air-shock velocities and has previously been demonstrated for organic military explosives. Here, the LASEM technique has been extended to explosive formulations with metal additives. A comparison of the measured laser-induced air-shock velocities for TNT, RDX, DNTF, and LLM-172 doped with Al or B to the detonation velocities predicted by the thermochemical code CHEETAH for inert or active metal participation demonstrates that LASEM has potential for predicting the early time (<10  μs) participation of metal additives in detonation events. The LASEM results show that while Al is mostly inert at early times in the detonation event (confirmed from large-scale detonation testing), B is active-and reducing the amount of hydrogen present during the early chemical reactions increases the resulting estimated detonation velocities.

  15. Development of magnetodielectric materials to be used in additive manufacturing processes for high-frequency applications

    NASA Astrophysics Data System (ADS)

    Parsons, Paul Emerson, II

    Electrical devices for very-high frequency (VHF, 0.03 -- 0.3 GHz) and ultra-high frequency (UHF, 0.3 -- 3.0 GHz) are commonly used for communications. However, the wavelengths, lambda, of these frequency bands correspond to lengths between 10 and 0.1 m, resulting in prohibitively large devices. Materials with an index of refraction, n, greater than 1 can be used to effectively shrink these devices by a factor of 1/ n. In this thesis, magnetodielectric materials (MDM), where n ≥1, have been made to be used in additive manufacturing processes with strict particle size requirements and were developed using various methods, such as polyol reduction and conventional ceramic solid state processing. These materials were characterized using x-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), vibrating sample magnetometry (VSM), to determine their crystalline, physical, and direct current (DC) magnetization properties. The techniques used to synthesize the MDM yielded particles that were chemically similar, but had drastically different physical properties which heavily influences their high-frequency electromagnetic properties. These materials were then uniformly dispersed into a non-conducting medium, such as a low-electrical loss polymer or resin, and formed into composite samples with variable volumetric loading. These composite samples were measured using several techniques to characterize the frequency-dependent electromagnetic (EM) properties, such as relative permeability, relative permittivity, and their respective losses. Finite element method (FEM) simulations were performed using these MDM-composites to design a spiral antenna to be used at approximately 585 MHz.

  16. Materials Technology Support for Radioisotope Power Systems Final Report

    SciTech Connect

    Daniel P. Kramer; Chadwick D. Barklay

    2008-10-07

    Over the period of this sponsored research, UDRI performed a number of materials related tasks that helped to facilitate increased understanding of the properties and applications of a number of candidate program related materials including; effects of neutron irradiation on tantalum alloys using a 500kW reactor, thermodynamic based modeling of the chemical species in weld pools, and the application of candidate coatings for increased oxidation resistance of FWPF (Fine Weave Pierced Fabric) modules.

  17. Process feasibility study in support of silicon material task 1

    NASA Technical Reports Server (NTRS)

    Yaws, C. L.; Li, K. Y.; Hopper, J. R.; Fang, C. S.; Hansen, K. C.

    1981-01-01

    Results for process system properties, chemical engineering and economic analyses of the new technologies and processes being developed for the production of lower cost silicon for solar cells are presented. Analyses of process system properties are important for chemical materials involved in the several processes under consideration for semiconductor and solar cell grade silicon production. Major physical, thermodynamic and transport property data are reported for silicon source and processing chemical materials.

  18. Carbon supports from natural organic materials and carbon-supported palladium catalysts

    SciTech Connect

    Kuznetsov, B.N.

    2007-07-15

    Experimental data are presented concerning the influence of preparation conditions on the pore structure of carbon supports obtained from different types of plant biomass, thermally expanded graphites, and chemically modified anthracites, on the distribution and particle size of supported palladium, and on the activity of the supported catalyst in the liquid-phase hydrogenation of hex-1-ene and cyclohexene.

  19. Mission and spacecraft support functions of the Materials Engineering Branch: A space oriented technology resource

    NASA Technical Reports Server (NTRS)

    Fisher, A.; Staugaitis, C. L.

    1974-01-01

    The capabilities of the Materials Engineering Branch (MEB) of the Goddard Space Flight Center, Greenbelt, Maryland, are surveyed. The specific functions of spacecraft materials review, materials processing and information dissemination, and laboratory support, are outlined in the Activity Report. Further detail is provided by case histories of laboratory satellite support and equipment. Project support statistics are shown, and complete listings of MEB publications, patents, and tech briefs are included. MEB staff, and their respective discipline areas and spacecraft liaison associations, are listed.

  20. 30 CFR 75.214 - Supplemental support materials, equipment and tools.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.214 Supplemental support materials, equipment and tools. (a) A supply of supplementary roof support... shall be sufficient to support the roof if adverse roof conditions are encountered, or in the event...

  1. 30 CFR 75.214 - Supplemental support materials, equipment and tools.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.214 Supplemental support materials, equipment and tools. (a) A supply of supplementary roof support... shall be sufficient to support the roof if adverse roof conditions are encountered, or in the event...

  2. U.S. Support for UN Peacekeeping: Areas for Additional DOD Assistance

    DTIC Science & Technology

    2007-09-01

    Operation Centers (JOCs) and Joint Military Analysis Cells ( JMACs ) as well as procedures for crisis response for missions have been established. The...coordination and use of IT capacities in the field, particularly in support of JOC/ JMAC .95 It also needs a better public information capacity in the UN HQ and

  3. Effects of Coating Materials and Mineral Additives on Nitrate Reduction by Zerovalent Iron

    NASA Astrophysics Data System (ADS)

    Kim, K. H.; Jeong, H. Y.; Lee, S.; Kang, N.; Choi, H. J.; Park, M.

    2015-12-01

    In efforts to facilitate nitrate removal, a variety of coating materials and mineral additives were assessed for their effects on the nitrate reduction by zerovalent iron (ZVI). Coated ZVIs were prepared by reacting Fe particles with Cr(III), Co(II), Ni(II), Cu(II), and S(-II) solutions under anoxic conditions, with the resultant materials named Cr/Fe, Co/Fe, Ni/Fe, Cu/Fe, and FeS/Fe, respectively. The mineral additives used, synthesized or purchased, included goethite, magnetite, and hydrous ferric oxide (HFO). Kinetic experiments were performed using air-tight serum vials containing 1.0 g Fe (uncoated or coated forms) in 15 mL of 100 mg NO3×N/L solutions with pH buffered at 7.0. To monitor the reaction progress, the solution phase was analyzed for NO3-, NO2-, and NH4+ on an ion chromatography, while the headspace was analyzed for H2, N2, and O2 on a gas chromatography. By uncoated Fe, ca. 60% of nitrate was reductively transformed for 3.6 h, with NH4+ being the predominant product. Compared with uncoated one, Cr/Fe, Co/Fe, and Cu/Fe showed faster removal rates of nitrate. The observed reactivity enhancement was thought to result from additional reduction of nitrate by H atoms adsorbed on the surface of Cr, Co, or Cu metal. In contrast, both Ni/Fe and FeS/Fe showed slower removal of nitrate than uncoated Fe. In both cases, the coating, which highly disfavors the adsorption of nitrate, would form on the Fe surface. When goethite, HFO, and magnetite were amended, the nitrate reduction by Fe was significantly increased, with the effect being most evident with HFO. Although not capable of reducing nitrate, the mineral additives would serve as crystal nuclei for the corrosion products of Fe, thus making the development of passivation layers on the Fe surface less. In the future, we will perform a kinetic modeling of the experimental data to assess the relative contribution of multiple reaction paths in the nitrate reduction by Fe.

  4. Research Opportunities Supporting the Vision for Space Exploration from the Transformation of the Former Microgravity Materials Science Program

    NASA Technical Reports Server (NTRS)

    Clinton, R. G., Jr.; Szofran, Frank; Bassler, Julie A.; Schlagheck, Ronald A.; Cook, Mary Beth

    2005-01-01

    The Microgravity Materials Science Program established a strong research capability through partnerships between NASA and the scientific research community. With the announcement of the vision for space exploration, additional emphasis in strategic materials science areas was necessary. The President's Commission recognized that achieving its exploration objectives would require significant technical innovation, research, and development in focal areas defined as "enabling technologies." Among the 17 enabling technologies identified for initial focus were: advanced structures, advanced power and propulsion; closed-loop life support and habitability; extravehicular activity systems; autonomous systems and robotics; scientific data collection and analysis, biomedical risk mitigation; and planetary in situ resource utilization. Mission success may depend upon use of local resources to fabricate a replacement part to repair a critical system. Future propulsion systems will require materials with a wide range of mechanical, thermophysical, and thermochemical properties, many of them well beyond capabilities of today's materials systems. Materials challenges have also been identified by experts working to develop advanced life support systems. In responding to the vision for space exploration, the Microgravity Materials Science Program aggressively transformed its research portfolio and focused materials science areas of emphasis to include space radiation shielding; in situ fabrication and repair for life support systems; in situ resource utilization for life support consumables; and advanced materials for exploration, including materials science for space propulsion systems and for life support systems. The purpose of this paper is to inform the scientific community of these new research directions and opportunities to utilize their materials science expertise and capabilities to support the vision for space exploration.

  5. Laser powder bed fusion additive manufacturing of metals; physics, computational, and materials challenges

    NASA Astrophysics Data System (ADS)

    King, W. E.; Anderson, A. T.; Ferencz, R. M.; Hodge, N. E.; Kamath, C.; Khairallah, S. A.; Rubenchik, A. M.

    2015-12-01

    The production of metal parts via laser powder bed fusion additive manufacturing is growing exponentially. However, the transition of this technology from production of prototypes to production of critical parts is hindered by a lack of confidence in the quality of the part. Confidence can be established via a fundamental understanding of the physics of the process. It is generally accepted that this understanding will be increasingly achieved through modeling and simulation. However, there are significant physics, computational, and materials challenges stemming from the broad range of length and time scales and temperature ranges associated with the process. In this paper, we review the current state of the art and describe the challenges that need to be met to achieve the desired fundamental understanding of the physics of the process.

  6. Laser powder bed fusion additive manufacturing of metals; physics, computational, and materials challenges

    SciTech Connect

    King, W. E.; Anderson, A. T.; Ferencz, R. M.; Hodge, N. E.; Kamath, C.; Khairallah, S. A.; Rubencik, A. M.

    2015-12-29

    The production of metal parts via laser powder bed fusion additive manufacturing is growing exponentially. However, the transition of this technology from production of prototypes to production of critical parts is hindered by a lack of confidence in the quality of the part. Confidence can be established via a fundamental understanding of the physics of the process. It is generally accepted that this understanding will be increasingly achieved through modeling and simulation. However, there are significant physics, computational, and materials challenges stemming from the broad range of length and time scales and temperature ranges associated with the process. In this study, we review the current state of the art and describe the challenges that need to be met to achieve the desired fundamental understanding of the physics of the process.

  7. Defect Characterization for Material Assurance in Metal Additive Manufacturing (FY15-0664)

    SciTech Connect

    Salzbrenner, Bradley; Boyce, Brad; Jared, Bradley Howell; Rodelas, Jeffrey; Laing, John Robert

    2016-02-01

    No industry-wide standards yet exist for minimum properties in additively manufactured (AM) metals. While AM alloys such as 17-4 precipitation hardened stainless steel have been shown to have average properties that can be comparable to wrought or cast product, they suffer from inconsistent performance. Variability in the feedstock powder, feature sizes, thermal history, and laser performance can lead to unpredictable surface finish, chemistry, phase content, and defects. To address this issue, rapid, efficient, high-throughput mechanical testing and data analysis was developed, providing profound statistical insight into the stochastic variability in properties. With this new approach, 1000’s of comprehensive tensile tests can be performed for the cost of 10’s of conventional tests. This new high-throughput approach provides a material qualification pathway that is commensurate with the quick turn-around benefit of AM.

  8. Laser powder bed fusion additive manufacturing of metals; physics, computational, and materials challenges

    SciTech Connect

    King, W. E.; Anderson, A. T.; Ferencz, R. M.; Hodge, N. E.; Khairallah, S. A.; Kamath, C.; Rubenchik, A. M.

    2015-12-15

    The production of metal parts via laser powder bed fusion additive manufacturing is growing exponentially. However, the transition of this technology from production of prototypes to production of critical parts is hindered by a lack of confidence in the quality of the part. Confidence can be established via a fundamental understanding of the physics of the process. It is generally accepted that this understanding will be increasingly achieved through modeling and simulation. However, there are significant physics, computational, and materials challenges stemming from the broad range of length and time scales and temperature ranges associated with the process. In this paper, we review the current state of the art and describe the challenges that need to be met to achieve the desired fundamental understanding of the physics of the process.

  9. Laser powder bed fusion additive manufacturing of metals; physics, computational, and materials challenges

    DOE PAGES

    King, W. E.; Anderson, A. T.; Ferencz, R. M.; ...

    2015-12-29

    The production of metal parts via laser powder bed fusion additive manufacturing is growing exponentially. However, the transition of this technology from production of prototypes to production of critical parts is hindered by a lack of confidence in the quality of the part. Confidence can be established via a fundamental understanding of the physics of the process. It is generally accepted that this understanding will be increasingly achieved through modeling and simulation. However, there are significant physics, computational, and materials challenges stemming from the broad range of length and time scales and temperature ranges associated with the process. In thismore » study, we review the current state of the art and describe the challenges that need to be met to achieve the desired fundamental understanding of the physics of the process.« less

  10. Process Feasibility Study in Support of Silicon Material, Task 1

    NASA Technical Reports Server (NTRS)

    Li, K. Y.; Hansen, K. C.; Yaws, C. L.

    1979-01-01

    During this reporting period, major activies were devoted to process system properties, chemical engineering and economic analyses. Analyses of process system properties was continued for materials involved in the alternate processes under consideration for solar cell grade silicon. The following property data are reported for silicon tetrafluoride: critical constants, vapor pressure, heat of varporization, heat capacity, density, surface tension, viscosity, thermal conductivity, heat of formation and Gibb's free energy of formation. Chemical engineering analysis of the BCL process was continued with primary efforts being devoted to the preliminary process design. Status and progress are reported for base case conditions; process flow diagram; reaction chemistry; material and energy balances; and major process equipment design.

  11. Passive vibration control in rotor dynamics: Optimization of composed support using viscoelastic materials

    NASA Astrophysics Data System (ADS)

    Ribeiro, Eduardo Afonso; Pereira, Jucélio Tomás; Alberto Bavastri, Carlos

    2015-09-01

    One of the major reasons for inserting damping into bearings is that rotating machines are often requested in critical functioning conditions having sometimes to function under dynamic instability or close to critical speeds. Hydrodynamic and magnetic bearings have usually been used for this purpose, but they present limitations regarding costs and operation, rendering the use of viscoelastic supports a feasible solution for vibration control in rotating machines. Most papers in the area use simple analytic or single degree of freedom models for the rotor as well as classic mechanical models of linear viscoelasticity for the support - like Maxwell, Kelvin-Voigt, Zenner, four-element, GHM models and even frequency independent models - but they lack the accuracy of fractional models in a large range of frequency and temperature regarding the same number of coefficients. Even in those works, the need to consider the addition of degrees of freedom to the support is evident. However, so far no paper has been published focusing on a methodology to determine the optimal constructive form for any viscoelastic support in which the rotor is discretized by finite elements associated to an accurate model for characterizing the viscoelastic material. In general, the support is meant to be a simple isolation system, and the fact the stiffness matrix is complex and frequency-temperature dependent - due to its viscoelastic properties - forces the traditional methods to require an extremely long computing time, thus rendering them too time consuming in an optimization environment. The present work presents a robust methodology based mainly on generalized equivalent parameters (GEP) - for an optimal design of viscoelastic supports for rotating machinery - aiming at minimizing the unbalance frequency response of the system using a hybrid optimization technique (genetic algorithms and Nelder-Mead method). The rotor is modeled based on the finite element method using Timoshenko's thick

  12. Materials support for HITAF. Final report for Phase 1

    SciTech Connect

    Breder, K.; Tennery, V.J.

    1995-03-01

    Improvements in coal-fired systems will require a change from steam turbines to gas turbines using air as working fluid; pressurized ceramic heat exchangers operating up to 1600 C will be needed. Leading candidate materials are SiC-based ceramics. Mechanical properties of 3 materials are compared in this work: NT230 Si/SiC from Saint Gobain Norton, {beta}-SiC from Coors Ceramics Co., and Lanxide DIMOX SiCp/Al{sub 2}O{sub 3} from Du Pont Lanxide Composites Inc. The first material is siliconized Si carbide, the second is sintered. They all were tested in 4-point flexure at RT and 1100 and 1400 C. Fast-fracture tests were carried out. Slow crack growth was investigated. Failure modes were studied using optical microscopy and SEM. Four materials were exposed to two coal ashes at two different temperatures. In the comparison, Coors {beta}-SiC stands out from a strength and reliability standpoint when exposed to air at high temperatures. Lanxide DIMOX withstood coal ash exposure well.

  13. Action Research to Support Teachers' Classroom Materials Development

    ERIC Educational Resources Information Center

    Edwards, Emily; Burns, Anne

    2016-01-01

    Language teachers constantly create, adapt and evaluate classroom materials to develop new curricula and meet their learners' needs. It has long been argued (e.g. by Stenhouse, L. [1975]. "An Introduction to Curriculum Research and Development." London: Heinemann) that teachers themselves, as opposed to managers or course book writers,…

  14. Develop Improved Materials to Support the Hydrogen Economy

    SciTech Connect

    Dr. Michael C. Martin

    2012-07-18

    The Edison Materials Technology Center (EMTEC) solicited and funded hydrogen infrastructure related projects that have a near term potential for commercialization. The subject technology of each project is related to the US Department of Energy hydrogen economy goals as outlined in the multi-year plan titled, 'Hydrogen, Fuel Cells and Infrastructure Technologies Program Multi-Year Research, Development and Demonstration Plan.' Preference was given to cross cutting materials development projects that might lead to the establishment of manufacturing capability and job creation. The Edison Materials Technology Center (EMTEC) used the US Department of Energy hydrogen economy goals to find and fund projects with near term commercialization potential. An RFP process aligned with this plan required performance based objectives with go/no-go technology based milestones. Protocols established for this program consisted of a RFP solicitation process, white papers and proposals with peer technology and commercialization review (including DoE), EMTEC project negotiation and definition and DoE cost share approval. Our RFP approach specified proposals/projects for hydrogen production, hydrogen storage or hydrogen infrastructure processing which may include sensor, separator, compression, maintenance, or delivery technologies. EMTEC was especially alert for projects in the appropriate subject area that have cross cutting materials technology with near term manufacturing and commercialization opportunities.

  15. Information Support for Using Open Learning Materials within Engineering Education.

    ERIC Educational Resources Information Center

    Cox, Stephen M.; Davies, D. T.

    1987-01-01

    Reviewed are some current trends in engineering education in the UK, particularly those toward open and distance learning. A case study is provided that shows a recent move to develop relevant and up-to-date course materials in the area of Advanced Manufacturing Technology for undergraduates through collaboration between academic and library…

  16. Physics of Granular Materials: Investigations in Support of Astrobiology

    NASA Technical Reports Server (NTRS)

    Marshall, John R.

    2002-01-01

    This publication list is submitted as a summary of the work conducted under Cooperative Agreement 1120. The goal of the 1120 research was to study granular materials within a planetary, astrophysical, and astrobiological context. This involved research on the physical, mechanical and electrostatic properties of granular systems, as well as the examination of these materials with atomic force microscopy and x-ray analysis. Instruments for analyzing said materials in planetary environments were developed, including the MECA (Mars Environment Compatibility Assessment) experiment for the MSP '01 lander, the ECHOS/MATADOR experiment for the MSP '03 lander, an ISRU experiment for the '03 lander, and MiniLEAP technology. Flight experiments for microgravity (Space Station and Shuttle) have also been developed for the study of granular materials. As expressed in the publications, work on 1120 encompassed laboratory research, theoretical modeling, field experiments, and flight experiments: a series of successful new models were developed for understanding the behavior of triboelectrostatically charged granular masses, and 4 separate instruments were selected for space flight. No inventions or patents were generated by the research under this Agreement.

  17. Characteristics of phase-change materials containing oxide nano-additives for thermal storage

    PubMed Central

    2012-01-01

    In this study, the authors report the production of nanocomposite-enhanced phase-change materials (NEPCMs) using the direct-synthesis method by mixing paraffin with alumina (Al2O3), titania (TiO2), silica (SiO2), and zinc oxide (ZnO) as the experimental samples. Al2O3, TiO2, SiO2, and ZnO were dispersed into three concentrations of 1.0, 2.0, and 3.0 wt.%. Through heat conduction and differential scanning calorimeter experiments to evaluate the effects of varying concentrations of the nano-additives on the heat conduction performance and thermal storage characteristics of NEPCMs, their feasibility for use in thermal storage was determined. The experimental results demonstrate that TiO2 is more effective than the other additives in enhancing both the heat conduction and thermal storage performance of paraffin for most of the experimental parameters. Furthermore, TiO2 reduces the melting onset temperature and increases the solidification onset temperature of paraffin. This allows the phase-change heat to be applicable to a wider temperature range, and the highest decreased ratio of phase-change heat is only 0.46%, compared to that of paraffin. Therefore, this study demonstrates that TiO2, added to paraffin to form NEPCMs, has significant potential for enhancing the thermal storage characteristics of paraffin. PMID:23127224

  18. Enhancement of elemental mercury adsorption by silver supported material.

    PubMed

    Khunphonoi, Rattabal; Khamdahsag, Pummarin; Chiarakorn, Siriluk; Grisdanurak, Nurak; Paerungruang, Adjana; Predapitakkun, Somrudee

    2015-06-01

    Mercury, generally found in natural gas, is extremely hazardous. Although average mercury levels are relatively low, they are further reduced to comply with future mercury regulations, which are stringent in order to avoid releasing to the environment. Herein, vapor mercury adsorption was therefore investigated using two kinds of supports, granular activated carbon (GAC) and titanium dioxide (TiO2). Both supports were impregnated by silver (5 and 15 wt.%), before testing against a commercial adsorbent (sulfur-impregnated activated carbon, SAC). The adsorption isotherm, kinetics, and its thermodynamics of mercury adsorption were reported. The results revealed that Langmuir isotherm provided a better fit to the experimental data. Pseudo second-order was applicable to describe adsorption kinetics. The higher uniform Ag dispersion was a key factor for the higher mercury uptake. TiO2 supported silver adsorbent showed higher mercury adsorption than the commercial one by approximately 2 times. Chemisorption of mercury onto silver active sites was confirmed by an amalgam formation found in the spent adsorbents.

  19. Process feasibility study in support of silicon material task 1

    NASA Technical Reports Server (NTRS)

    Fang, C. S.; Hansen, K. C.; Miller, J. W., Jr.; Yaws, C. L.

    1978-01-01

    Initial results for gas thermal conductivity of silicon tetrafluoride and trichlorosilane are reported in respective temperature ranges of 25 to 400 C and 50 to 400 C. For chemical engineering analyses, the preliminary process design for the original silane process of Union Carbide was completed for Cases A and B, Regular and Minimum Process Storage. Included are raw material usage, utility requirements, major process equipment lists, and production labor requirements. Because of the large differences in surge tankage between major unit operations the fixed capital investment varied from $19,094,000 to $11,138,000 for Cases A and B, respectively. For the silane process the original flowsheet was revised for a more optimum arrangement of major equipment, raw materials and operating conditions. The initial issue of the revised flowsheet (Case C) for the silane process indicated favorable cost benefits over the original scheme.

  20. Process feasibility study in support of silicon material task 1

    NASA Technical Reports Server (NTRS)

    Li, K. Y.; Hansen, K. C.; Yaws, C. L.

    1978-01-01

    Process system properties are analyzed for materials involved in the alternate processes under consideration for solar cell grade silicon. The following property data are reported for trichlorosilane: critical constants, vapor pressure, heat of vaporization, gas heat capacity, liquid heat capacity, density, surface tension, viscosity, thermal conductivity, heat of formation, and Gibb's free energy of formation. Work continued on the measurement of gas viscosity values of silicon source materials. Gas phase viscosity values for silicon tetrafluoride between 40 C and 200 C were experimentally determined. Major efforts were expended on completion of the preliminary economic analysis of the silane process. Cost, sensitivity and profitability analysis results are presented based on a preliminary process design of a plant to produce 1,000 metric tons/year of silicon by the revised process.

  1. Process feasibility study in support of silicon material, task 1

    NASA Technical Reports Server (NTRS)

    Li, K. Y.; Hansen, K. C.; Yaws, C. L.

    1979-01-01

    Analyses of process system properties were continued for materials involved in the alternate processes under consideration for semiconductor silicon. Primary efforts centered on physical and thermodynamic property data for dichlorosilane. The following property data are reported for dichlorosilane which is involved in processing operations for solar cell grade silicon: critical temperature, critical pressure, critical volume, critical density, acentric factor, vapor pressure, heat of vaporization, gas heat capacity, liquid heat capacity and density. Work was initiated on the assembly of a system to prepare binary gas mixtures of known proportions and to measure the thermal conductivity of these mixtures between 30 and 350 C. The binary gas mixtures include silicon source material such as silanes and halogenated silanes which are used in the production of semiconductor silicon.

  2. 15 CFR 930.127 - Briefs and supporting materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (Continued) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL... General Counsel for Ocean Services (GCOS), NOAA, 1305 East West Highway, Room 6111 SSMC4, Silver Spring.... The Secretary may determine, on the Secretary's own initiative, that additional information...

  3. Polymeric Materials With Additives for Durability and Radiation Shielding in Space

    NASA Technical Reports Server (NTRS)

    Kiefer, Richard

    2011-01-01

    Polymeric materials are attractive for use in space structures because of their light weight and high strength In addition, polymers are made of elements with low atomic numbers (Z), primarily carbon (C), hydrogen (H), oxygen (0), and nitrogen (N) which provide the best shielding from galactic cosmic rays (GCR) (ref. 1). Galactic cosmic rays are composed primarily of nuclei (i.e., fully ionized atoms) plus a contribution of about 2% from electrons and positrons. There is a small but significant component of GCR particles with high charge (Z > 10) and high energy (E >100 GeV) (ref. 2). These so-called HZE particles comprise only 1 to 2% of the cosmic ray fluence but they interact with very high specific ionization and contribute 50% of the long- term dose to humans. The best shield for this radiation would be liquid hydrogen, which is not feasible. For this reason, hydrogen-containing polymers make the most effective practical shields. Moreover, neutrons are formed in the interactions of GCR particles with materials. Neutrons can only lose energy by collisions or reactions with a nucleus since they are uncharged. This is a process that is much less probable than the Coulombic interactions of charged particles. Thus, neutrons migrate far from the site of the reaction in which they were formed. This increases the probability of neutrons reaching humans or electronic equipment. Fast neutrons (> 1 MeV) can interact with silicon chips in electronic equipment resulting in the production of recoil ions which can cause single event upsets (SEU) in sensitive components (ref. 3). Neutrons lose energy most effectively by elastic collisions with light atoms, particularly hydrogen atoms. Therefore, hydrogen-containing polymers are not only effective in interacting with GCR particles; they are also effective in reducing the energy of the neutrons formed in the interactions.

  4. 21 CFR 570.14 - Indirect food additives resulting from packaging materials for animal feed and pet food.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Indirect food additives resulting from packaging..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES General Provisions § 570.14 Indirect food additives resulting from packaging materials for animal feed...

  5. 21 CFR 570.14 - Indirect food additives resulting from packaging materials for animal feed and pet food.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Indirect food additives resulting from packaging..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES General Provisions § 570.14 Indirect food additives resulting from packaging materials for animal feed...

  6. 21 CFR 570.13 - Indirect food additives resulting from packaging materials prior sanctioned for animal feed and...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Indirect food additives resulting from packaging materials prior sanctioned for animal feed and pet food. 570.13 Section 570.13 Food and Drugs FOOD AND DRUG... FOOD ADDITIVES General Provisions § 570.13 Indirect food additives resulting from packaging...

  7. 21 CFR 570.14 - Indirect food additives resulting from packaging materials for animal feed and pet food.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Indirect food additives resulting from packaging..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES General Provisions § 570.14 Indirect food additives resulting from packaging materials for animal feed...

  8. 21 CFR 570.13 - Indirect food additives resulting from packaging materials prior sanctioned for animal feed and...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Indirect food additives resulting from packaging materials prior sanctioned for animal feed and pet food. 570.13 Section 570.13 Food and Drugs FOOD AND DRUG... FOOD ADDITIVES General Provisions § 570.13 Indirect food additives resulting from packaging...

  9. 21 CFR 570.13 - Indirect food additives resulting from packaging materials prior sanctioned for animal feed and...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Indirect food additives resulting from packaging materials prior sanctioned for animal feed and pet food. 570.13 Section 570.13 Food and Drugs FOOD AND DRUG... FOOD ADDITIVES General Provisions § 570.13 Indirect food additives resulting from packaging...

  10. Longevity of Emplacement Drift Ground Support Materials for LA

    SciTech Connect

    D. Tang

    2003-09-16

    The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the disruptive events features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for license application (TSPA-LA). A screening decision, either ''Included'' or ''Excluded,'' is given for each FEP, along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), and (f) [DIRS 156605]. The FEPs addressed in this report deal with both seismic and igneous disruptive events, such as fault displacements through the repository and an igneous intrusion into the repository. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). Previous versions of this report were developed to support the total system performance assessments (TSPA) for various prior repository designs. This revision addresses the repository design for the license application (LA).

  11. Sulfide oxidation in fluidized bed bioreactor using nylon support material.

    PubMed

    Midha, Varsha; Jha, M K; Dey, Apurba

    2012-01-01

    A continuous fluidized bed bioreactor (FBBR) with nylon support particles was used to treat synthetic sulfide wastewater at different hydraulic retention time of 25, 50 and 75 min and upflow velocity of 14, 17 and 20 m/hr. The effects of upflow velocity, hydraulic retention time and reactor operation time on sulfide oxidation rate were studied using statistical model. Mixed culture obtained from the activated sludge, taken from tannery effluent treatment plant, was used as a source for microorganisms. The diameter and density of the nylon particles were 2-3 mm and 1140 kg/m3, respectively. Experiments were carried out in the reactor at a temperature of (30 +/- 2) degrees C, at a fixed bed height of 16 cm after the formation of biofilm on the surface of support particles. Biofilm thickness reached (42 +/- 3) microm after 15 days from reactor start-up. The sulfide oxidation, sulfate and sulfur formation is examined at all hydraulic retention times and upflow velocities. The results indicated that almost 90%-92% sulfide oxidation was achieved at all hydraulic retention times. Statistical model could explain 94% of the variability and analysis of variance showed that upflow velocity and hydraulic retention time slightly affected the sulfide oxidation rate. The highest sulfide oxidation of 92% with 70% sulfur was obtained at hydraulic retention time of 75 min and upflow velocity of 14 m/hr.

  12. Improved thermal storage material for portable life support systems

    NASA Technical Reports Server (NTRS)

    Kellner, J. D.

    1975-01-01

    The availability of thermal storage materials that have heat absorption capabilities substantially greater than water-ice in the same temperature range would permit significant improvements in performance of projected portable thermal storage cooling systems. A method for providing increased heat absorption by the combined use of the heat of solution of certain salts and the heat of fusion of water-ice was investigated. This work has indicated that a 30 percent solution of potassium bifluoride (KHF2) in water can absorb approximately 52 percent more heat than an equal weight of water-ice, and approximately 79 percent more heat than an equal volume of water-ice. The thermal storage material can be regenerated easily by freezing, however, a lower temperature must be used, 261 K as compared to 273 K for water-ice. This work was conducted by the United Aircraft Research Laboratories as part of a program at Hamilton Standard Division of United Aircraft Corporation under contract to NASA Ames Research Center.

  13. Sign-Supported English: Is It Effective at Teaching Vocabulary to Young Children with English as an Additional Language?

    ERIC Educational Resources Information Center

    Marshall, Chloë R.; Hobsbaum, Angela

    2015-01-01

    Background: Children who are learning English as an Additional Language (EAL) may start school with smaller vocabularies than their monolingual peers. Given the links between vocabulary and academic achievement, it is important to evaluate interventions that are designed to support vocabulary learning in this group of children. Aims: To evaluate…

  14. Metallic and Non-Metallic Materials for the Primary Support Structure

    SciTech Connect

    RA Wolf; RP Corson

    2006-02-21

    The primary support structure (PSS) is required for mechanical support of reactor module (RM) components and mounting of the RM to the spacecraft. The PSS would provide support and accept all loads associated with dynamic (e. g., launch and maneuvering) or thermally induced loading. Prior to termination of NRPCT involvement in Project Prometheus, the NRPCT Mechanical Systems team developed preliminary finite element models to gain a basic understanding of the behavior of the structure, but optimization of the models, specification of the final design, and materials selection were not completed. The Space Plant Materials team had evaluated several materials for potential use in the primary support structure, namely titanium alloys, beryllium, aluminum alloys and carbon-carbon composites. The feasibility of application of each material system was compared based on mass, stiffness, thermal expansion, and ease of fabrication. Due to insufficient data on environmental factors, such as temperatures and radiation, and limited modeling support, a final materials selection was not made.

  15. New supported beta-amino alcohols as efficient catalysts for the enantioselective addition of diethylzinc to benzaldehyde under flow conditions.

    PubMed

    Burguete, M Isabel; García-Verdugo, Eduardo; Vicent, María J; Luis, Santiago V; Pennemann, Helmut; Graf von, Keyserling Nikolai; Martens, Jürgen

    2002-10-31

    [formula: see text] Polymeric monoliths 10 containing an amino alcohol moiety derived from an industrial waste material represent one of the best ligands for the enantioselective catalytic addition of ZnEt2 to benzaldehyde (99% ee), being recoverable and usable under flow conditions.

  16. Byssus thread: a novel support material for urease immobilization.

    PubMed

    Mishra, Neelam; Pithawala, Kespi; Bahadur, Anita

    2011-12-01

    Byssus threads are tough biopolymer produced by mussels (Mytilus viridis) to attach themselves to rocks. These were collected from mussels in their natural habitat (N) and from animals maintained in laboratory condition (L) as a novel support. Byssus thread surfaces were characterized by SEM analysis, chemically modified and used for adsorption of urease. The efficiency of the immobilization was calculated by examining the relative enzyme activity of free and the immobilized urease. The pH stabilities of immobilized urease were higher (0.5 unit) than free enzyme. Immobilized enzymes on byssus (both N and L) when stored at 6 °C retained 50% of its activity after 30 days, but they were more stable in dry condition. The optimum temperature of immobilized enzymes was found to increase (25 °C). A Michaelis-Menten constant (K (m)) value for immobilized urease was also elevated (2.08 mol).

  17. Process Feasibility Study in Support of Silicon Material Task 1

    NASA Technical Reports Server (NTRS)

    Li, K. Y.; Hansen, K. C.; Yaws, C. L.

    1979-01-01

    Analysis of process system properties was continued for silicon source materials under consideration for producing silicon. The following property data are reported for dichlorosilane which is involved in processing operations for silicon: critical constants, vapor pressure, heat of vaporization, heat capacity, density, surface tension, thermal conductivity, heat of formation and Gibb's free energy of formation. The properties are reported as a function of temperature to permit rapid engineering usage. The preliminary economic analysis of the process is described. Cost analysis results for the process (case A-two deposition reactors and six electrolysis cells) are presented based on a preliminary process design of a plant to produce 1,000 metric tons/year of silicon. Fixed capital investment estimate for the plant is $12.47 million (1975 dollars) ($17.47 million, 1980 dollars). Product cost without profit is 8.63 $/kg of silicon (1975 dollars)(12.1 $/kg, 1980 dollars).

  18. In vitro cytotoxicity and surface topography evaluation of additive manufacturing titanium implant materials.

    PubMed

    Tuomi, Jukka T; Björkstrand, Roy V; Pernu, Mikael L; Salmi, Mika V J; Huotilainen, Eero I; Wolff, Jan E H; Vallittu, Pekka K; Mäkitie, Antti A

    2017-03-01

    Custom-designed patient-specific implants and reconstruction plates are to date commonly manufactured using two different additive manufacturing (AM) technologies: direct metal laser sintering (DMLS) and electron beam melting (EBM). The purpose of this investigation was to characterize the surface structure and to assess the cytotoxicity of titanium alloys processed using DMLS and EBM technologies as the existing information on these issues is scarce. "Processed" and "polished" DMLS and EBM disks were assessed. Microscopic examination revealed titanium alloy particles and surface flaws on the processed materials. These surface flaws were subsequently removed by polishing. Surface roughness of EBM processed titanium was higher than that of DMLS processed. The cytotoxicity results of the DMLS and EBM discs were compared with a "gold standard" commercially available titanium mandible reconstruction plate. The mean cell viability for all discs was 82.6% (range, 77.4 to 89.7) and 83.3% for the control reconstruction plate. The DMLS and EBM manufactured titanium plates were non-cytotoxic both in "processed" and in "polished" forms.

  19. Additivity of abrupt onset effects supports nonspatial distraction, not the capture of spatial attention.

    PubMed

    Folk, Charles L; Remington, Roger W; Wu, Shu-Chieh

    2009-02-01

    In a recent article, Schreij, Owens, and Theeuwes (2008) reported that abruptly onsetting distractors produce costs in performance even when spatial-cuing effects confirm the presence of a top-down set for color. The authors argued that these results show that abruptly onsetting new objects capture attention independent of a top-down set and, thus, provide conclusive evidence against the theory that attentional capture is contingent on top-down attentional control settings (Folk, Remington, & Johnston, 1992). In the following article, we argue that, contrary to the conclusion drawn by Schreij et al., their own data (1) disconfirm the claim that their abrupt onsets captured spatial attention and (2) are consistent with nonspatial interference accounts of singleton-distractor effects. In support of the nonspatial account, we show that in a paradigm similar to Schreij et al.'s, distractors that do not capture attention can nonetheless influence responses to a target. We conclude that the results of Schreij et al. do not represent a challenge to contingent capture theory.

  20. Data Collection Handbook to Support Modeling Impacts of Radioactive Material in Soil and Building Structures

    SciTech Connect

    Yu, Charley; Kamboj, Sunita; Wang, Cheng; Cheng, Jing-Jy

    2015-09-01

    This handbook is an update of the 1993 version of the Data Collection Handbook and the Radionuclide Transfer Factors Report to support modeling the impact of radioactive material in soil. Many new parameters have been added to the RESRAD Family of Codes, and new measurement methodologies are available. A detailed review of available parameter databases was conducted in preparation of this new handbook. This handbook is a companion document to the user manuals when using the RESRAD (onsite) and RESRAD-OFFSITE code. It can also be used for RESRAD-BUILD code because some of the building-related parameters are included in this handbook. The RESRAD (onsite) has been developed for implementing U.S. Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), crops and livestock, human intake, source characteristic, and building characteristic parameters are used in the RESRAD (onsite) code. The RESRAD-OFFSITE code is an extension of the RESRAD (onsite) code and can also model the transport of radionuclides to locations outside the footprint of the primary contamination. This handbook discusses parameter definitions, typical ranges, variations, and measurement methodologies. It also provides references for sources of additional information. Although this handbook was developed primarily to support the application of RESRAD Family of Codes, the discussions and values are valid for use of other pathway analysis models and codes.

  1. Guidelines for Supporting Re-Use of Existing Digital Learning Materials and Methods in Higher Education

    ERIC Educational Resources Information Center

    Schoonenboom, Judith; Sligte, Henk; Kliphuis, Eja

    2009-01-01

    The literature on the re-use of learning materials has largely focused on the development of materials. This paper explores how re-use can be stimulated after learning materials have been developed and made available. We searched for and developed guidelines that support staff and/or management most frequently adopt in cases of (un)successful…

  2. Supporting Preservice Elementary Teachers' Critique and Adaptation of Science Lesson Plans Using Educative Curriculum Materials

    ERIC Educational Resources Information Center

    Beyer, Carrie; Davis, Elizabeth A.

    2009-01-01

    Critiquing and adapting curriculum materials are essential teaching practices but challenging for many preservice teachers. This study explores the use of educative curriculum materials--materials intended to support both teacher and student learning--to help preservice elementary teachers develop their pedagogical design capacity for critiquing…

  3. Resource Materials To Support Your Environmental Education Efforts. EE-TIPS (Environmental Education Technical Information Packages).

    ERIC Educational Resources Information Center

    North American Association for Environmental Education, Troy, OH.

    This collection gathers together over 50 high-quality materials to support environmental education (EE) curricula. Because each community has unique environmental and educational needs, the guide includes a broad set of educational materials that can be adapted to a variety of settings. The materials can be used to supplement educational…

  4. Graphene supported graphone/graphane bilayer nanostructure material for spintronics.

    PubMed

    Ray, Sekhar C; Soin, Navneet; Makgato, Thuto; Chuang, C H; Pong, W F; Roy, Susanta S; Ghosh, Sarit K; Strydom, André M; McLaughlin, J A

    2014-01-24

    We report an investigation into the magnetic and electronic properties of partially hydrogenated vertically aligned few layers graphene (FLG) synthesized by microwave plasma enhanced chemical vapor deposition. The FLG samples are hydrogenated at different substrate temperatures to alter the degree of hydrogenation and their depth profile. The unique morphology of the structure gives rise to a unique geometry in which graphane/graphone is supported by graphene layers in the bulk, which is very different from other widely studied structures such as one-dimensional nanoribbons. Synchrotron based x-ray absorption fine structure spectroscopy measurements have been used to investigate the electronic structure and the underlying hydrogenation mechanism responsible for the magnetic properties. While ferromagnetic interactions seem to be predominant, the presence of antiferromagnetic interaction was also observed. Free spins available via the conversion of sp(2) to sp(3) hybridized structures, and the possibility of unpaired electrons from defects induced upon hydrogenation are thought to be likely mechanisms for the observed ferromagnetic orders.

  5. Materials study supporting thermochemical hydrogen cycle sulfuric acid decomposer design

    NASA Astrophysics Data System (ADS)

    Peck, Michael S.

    Increasing global climate change has been driven by greenhouse gases emissions originating from the combustion of fossil fuels. Clean burning hydrogen has the potential to replace much of the fossil fuels used today reducing the amount of greenhouse gases released into the atmosphere. The sulfur iodine and hybrid sulfur thermochemical cycles coupled with high temperature heat from advanced nuclear reactors have shown promise for economical large-scale hydrogen fuel stock production. Both of these cycles employ a step to decompose sulfuric acid to sulfur dioxide. This decomposition step occurs at high temperatures in the range of 825°C to 926°C dependent on the catalysis used. Successful commercial implementation of these technologies is dependent upon the development of suitable materials for use in the highly corrosive environments created by the decomposition products. Boron treated diamond film was a potential candidate for use in decomposer process equipment based on earlier studies concluding good oxidation resistance at elevated temperatures. However, little information was available relating the interactions of diamond and diamond films with sulfuric acid at temperatures greater than 350°C. A laboratory scale sulfuric acid decomposer simulator was constructed at the Nuclear Science and Engineering Institute at the University of Missouri-Columbia. The simulator was capable of producing the temperatures and corrosive environments that process equipment would be exposed to for industrialization of the sulfur iodide or hybrid sulfur thermochemical cycles. A series of boron treated synthetic diamonds were tested in the simulator to determine corrosion resistances and suitability for use in thermochemical process equipment. These studies were performed at twenty four hour durations at temperatures between 600°C to 926°C. Other materials, including natural diamond, synthetic diamond treated with titanium, silicon carbide, quartz, aluminum nitride, and Inconel

  6. [Multimedia educational material. A tool of support to the Otolaryngology training].

    PubMed

    Alvarez Marcos, C A; Llorente Pendás, J L; Martínez Nistal, A; Lana Fernández, A; Granda González, E; Sampedro Nuño, A; Suárez Nieto, C

    2005-01-01

    Due to multimedia technologies, the medical information has taken an extraordinary growing. Nevertheless, the education at University will turn out to be a more complex pedagogic process. We present a multimedia educational material (MEM), developed as an online course to "Seminars of Otolaryngology", and available free at the University website. MEM was designed and edited by, ENT teachers, pedagogues, and image and computer experts. It has been structured as a series of modules that integrate texts, images, movie clips, video, audio and animations. The schematic presentation stands out with progressive access to the topics through internal and external links. The pedagogic resources give additional support by learning objectives, glossary, references, index and searcher. Finally, the activities and instrumental simulations complete the training in diagnosis and treatment. The MEM is an interactive useful software program for medical training in Otolaryngology, without avoiding the key figure of the teacher.

  7. Linking process, structure, property, and performance for metal-based additive manufacturing: computational approaches with experimental support

    NASA Astrophysics Data System (ADS)

    Smith, Jacob; Xiong, Wei; Yan, Wentao; Lin, Stephen; Cheng, Puikei; Kafka, Orion L.; Wagner, Gregory J.; Cao, Jian; Liu, Wing Kam

    2016-04-01

    Additive manufacturing (AM) methods for rapid prototyping of 3D materials (3D printing) have become increasingly popular with a particular recent emphasis on those methods used for metallic materials. These processes typically involve an accumulation of cyclic phase changes. The widespread interest in these methods is largely stimulated by their unique ability to create components of considerable complexity. However, modeling such processes is exceedingly difficult due to the highly localized and drastic material evolution that often occurs over the course of the manufacture time of each component. Final product characterization and validation are currently driven primarily by experimental means as a result of the lack of robust modeling procedures. In the present work, the authors discuss primary detrimental hurdles that have plagued effective modeling of AM methods for metallic materials while also providing logical speculation into preferable research directions for overcoming these hurdles. The primary focus of this work encompasses the specific areas of high-performance computing, multiscale modeling, materials characterization, process modeling, experimentation, and validation for final product performance of additively manufactured metallic components.

  8. Preparations and properties of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials.

    PubMed

    Watanabe, Shoji

    2008-01-01

    This short review describes various types of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials. It is concerned with synthetic additives classified according to their functional groups; silicone compounds, carboxylic acids and dibasic acids, esters, Diels-Alder adducts, various polymers, nitrogen compounds, phosphoric esters, phosphonic acids, and others. Testing methods for water-soluble metal working fluids for aluminum alloy materials are described for a practical application in a laboratory.

  9. Advanced Materials in Support of EERE Needs to Advance Clean Energy Technologies Program Implementation

    SciTech Connect

    Liby, Alan L; Rogers, Hiram

    2013-10-01

    The goal of this activity was to carry out program implementation and technical projects in support of the ARRA-funded Advanced Materials in Support of EERE Needs to Advance Clean Energy Technologies Program of the DOE Advanced Manufacturing Office (AMO) (formerly the Industrial Technologies Program (ITP)). The work was organized into eight projects in four materials areas: strategic materials, structural materials, energy storage and production materials, and advanced/field/transient processing. Strategic materials included work on titanium, magnesium and carbon fiber. Structural materials included work on alumina forming austentic (AFA) and CF8C-Plus steels. The advanced batteries and production materials projects included work on advanced batteries and photovoltaic devices. Advanced/field/transient processing included work on magnetic field processing. Details of the work in the eight projects are available in the project final reports which have been previously submitted.

  10. Material Not Categorized As Waste (MNCAW) data report. Radioactive Waste Technical Support Program

    SciTech Connect

    Casey, C.; Heath, B.A.

    1992-11-01

    The Department of Energy (DOE), Headquarters, requested all DOE sites storing valuable materials to complete a questionnaire about each material that, if discarded, could be liable to regulation. The Radioactive Waste Technical Support Program entered completed questionnaires into a database and analyzed them for quantities and type of materials stored. This report discusses the data that TSP gathered. The report also discusses problems revealed by the questionnaires and future uses of the data. Appendices contain selected data about material reported.

  11. Visible Light Enabled Photocatalytic Splitting of Water over Spatially Isolated Semiconductors Supported Mesoporous Materials

    NASA Astrophysics Data System (ADS)

    Peng, Rui

    Hydrogen generation from photocatalytic splitting of water is an ideal scenario that possesses promise for the sustainable development of human society and the establishment of the ultimate "green," infinitely renewable energy system. This work contains a series of novel photocatalytic systems in which the photoactive chromophores and/or the co-catalysts were incorporated into highly periodically cubic-phased MCM-48 mesoporous materials to achieve significantly higher photocatalytic efficiencies compared with conventional semiconductor photocatalysts. Cubic-phased MCM-48 mesoporous materials were chosen as supports to accommodate the photoactive species throughout the entire work. Several unique and iconic properties of these materials, such as large surface area, highly uniform mesoscale pores arrayed in a long-range periodicity, and an interconnected network of three-dimensional sets of pores that were recognized as positive parameters facilitated the photogenerated charge transfer and promoted the photocatalytic performance of the encapsulated photoactive species. It was validated that in the CdS/TiO2-incorporated MCM-48 photocatalytic system, the solar hydrogen conversion efficiency was prevalently governed by the photogenerated electron injection efficiency from the CdS conduction band to that of TiO2. The use of MCM-48 mesoporous host materials enabled the high and even dispersion of both CdS and TiO 2 so that the intimate and sufficient contact between CdS and TiO 2 was realized. In addition, with the presence of both TiO2 and MCM-48 mesoporous support, the photostability of CdS species was dramatically enhanced compared with that of bare CdS or CdS-incorporated MCM-48 photocatalysts. In advance, by loading the RuO2 co-catalyst into the CdS/TiO 2-incorporated MCM-48 photocatalytic system, the photocatalytic splitting of pure water to generate both hydrogen and oxygen under visible light illumination was achieved. In the various Pd-assisted, TiO2-incorporated

  12. Hydrazide-functionalized affinity on conventional support materials for glycopeptide enrichment.

    PubMed

    Sajid, Muhammad Salman; Jabeen, Fahmida; Hussain, Dilshad; Ashiq, Muhammad Naeem; Najam-Ul-Haq, Muhammad

    2017-02-24

    In affinity chromatography, enrichment of biomolecules is dependent on the selection of affinity sites immobilized onto a suitable support material. A few hydrazide - functionalized materials with surface modification protocols compatible to conventional support materials like silica and cellulose are reported. The study demonstrates the modification/derivatization pathways that can be adopted to modify the support materials with similar surface chemistry like cellulose, poly(GMA/DVB), or diamond. Poly(GMA/DVB) and cellulose represent hydrophilic supports whereas diamond is a hydrophobic support material. SEM images of three materials provide surface morphology whereas FT-IR confirms reaction completion and derivatization. These hydrazide - functionalized materials are applied to fetuin digest for glycopeptides enrichment and subsequently for selectivity and sensitivity assessment. Statistically, poly(GMA/DVB) shows 85.7% sensitivity with specificity of 88.8% in the enrichment experiments. Diamond offers hydrophobic interactions to non-glycopeptides and they co-elute with glycopeptides, resulting in reduced sensitivity down to 69.2%. Poly(GMA/DVB) shows recovery up to 89%, while recovery for cellulose and diamond is 83 and 71%, respectively. The materials enrich mono-N-linked-glycosylated peptide from tryptic digest of chicken avidin spiked in fetuin digest. The hydrazide group density on cellulose, poly(GMA/DVB), and diamond is 2.8, 2.3, and 2.1 mmol/g, respectively; this contributes towards the specificity and sensitivity of designed materials. The materials are also applied to serum samples and enriched glycopeptides characteristic of serum glycoproteins of clinical importance. Therefore this study provides routes for the economical surface modifications of support materials and to fabricate affinity materials with improved efficiency. Graphical Abstract Glycopeptides enrichment by hydrazine affinity.

  13. Biological properties of IRM with the addition of hydroxyapatite as a retrograde root filling material.

    PubMed

    Owadally, I D; Chong, B S; Pitt Ford, T R; Wilson, R F

    1994-10-01

    The effect of adding 10% & 20% hydroxyapatite (HAP) on the antibacterial activity and cytotoxicity of IRM (Intermediate Restorative Material) when used as a retrograde root filling was compared with amalgam, a commonly used material. The antibacterial activity was assessed using the agar diffusion inhibitory test. Forty standardized pellets of each material were produced. Fresh materials, and materials aged for 1 week in sterile distilled water, were placed on blood agar plates inoculated with Streptococcus anginosus (milleri) or Enterococcus faecalis. The presence and diameter of zones of inhibition were recorded at intervals of 3, 7 and 10 days. There was no statistically significant overall difference in the response of the two bacteria tested. However, there were statistically significant overall differences in diameters of the zones of inhibition related to different materials, period of exposure and ageing of materials (P < 0.001). The diameter of the zones of inhibition increased with time for all materials, fresh and aged. IRM and both the HAP-modified forms produced large zones of inhibition. Amalgam produced no measureable zones of inhibition whether aged or fresh, regardless of period of exposure and was different from the other materials (P < 0.001). The cytotoxicity was assessed using the Millipore filter method. Ten standardized pellets of each material were produced and aged by storage in sterile distilled water for 72 h. Ten filters were included as controls. Amalgam produced a consistent cytotoxic score of 1, and the difference between amalgam and the other materials was statistically significant (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

  14. 45 CFR 1641.21 - Additional proceedings as to disputed material facts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... facts. 1641.21 Section 1641.21 Public Welfare Regulations Relating to Public Welfare (Continued) LEGAL... proceedings as to disputed material facts. (a) In actions not based upon a conviction or civil judgment under... of material fact, the IPA shall be afforded an opportunity to appear (with counsel, if...

  15. 45 CFR 1641.21 - Additional proceedings as to disputed material facts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... facts. 1641.21 Section 1641.21 Public Welfare Regulations Relating to Public Welfare (Continued) LEGAL... proceedings as to disputed material facts. (a) In actions not based upon a conviction or civil judgment under... of material fact, the IPA shall be afforded an opportunity to appear (with counsel, if...

  16. 45 CFR 1641.10 - Additional proceedings as to disputed material facts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... facts. 1641.10 Section 1641.10 Public Welfare Regulations Relating to Public Welfare (Continued) LEGAL... proceedings as to disputed material facts. (a) In actions not based upon a conviction or civil judgment under... of material fact, the IPA shall be afforded an opportunity to appear (with counsel, if...

  17. 45 CFR 1641.10 - Additional proceedings as to disputed material facts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... facts. 1641.10 Section 1641.10 Public Welfare Regulations Relating to Public Welfare (Continued) LEGAL... proceedings as to disputed material facts. (a) In actions not based upon a conviction or civil judgment under... of material fact, the IPA shall be afforded an opportunity to appear (with counsel, if...

  18. Aluminium content of some processed foods, raw materials and food additives in China by inductively coupled plasma-mass spectrometry.

    PubMed

    Deng, Gui-Fang; Li, Ke; Ma, Jing; Liu, Fen; Dai, Jing-Jing; Li, Hua-Bin

    2011-01-01

    The level of aluminium in 178 processed food samples from Shenzhen city in China was evaluated using inductively coupled plasma-mass spectrometry. Some processed foods contained a concentration of up to 1226 mg/kg, which is about 12 times the Chinese food standard. To establish the main source in these foods, Al levels in the raw materials were determined. However, aluminium concentrations in raw materials were low (0.10-451.5 mg/kg). Therefore, aluminium levels in food additives used in these foods was determined and it was found that some food additives contained a high concentration of aluminium (0.005-57.4 g/kg). The results suggested that, in the interest of public health, food additives containing high concentrations of aluminium should be replaced by those containing less. This study has provided new information on aluminium levels in Chinese processed foods, raw materials and a selection of food additives.

  19. Evaluation of fuel additives for reduction of material imcompatibilities in methanol-gasoline blends

    NASA Technical Reports Server (NTRS)

    Rodriguez, C. F.; Barbee, J. G.; Knutson, W. K.; Cuellar, J. P., Jr.

    1983-01-01

    Screening tests determined the efficacy of six commercially available additives as modifiers of methanol's corrosivity toward metals and its weakening of tensile properties of nonmetals in automotive fuel systems. From the screening phase, three additives which seemed to protect some of the metals were tested in higher concentrations and binary combinations in search of optimal application conditions. Results indicate that two of the additives have protective properties and combining them increases the protection of the metals corroded by methanol-gasoline blends. Half of the metals in the tests were not corroded. Testing at recommended concentrations and then at higher concentrations and in combinations shows that the additives would have no protective or harmful effects on the nonmetals. Two additives emerged as candidates for application to the protection of metals in automotive methanol-gasoline fuel systems. The additives tested were assigned letter codes to protect their proprietary nature.

  20. Effects of titanium addition on the microstructure of carbon/copper composite materials

    NASA Astrophysics Data System (ADS)

    Oku, Takeo; Oku, Tatsuo

    2007-01-01

    Carbon(C)/copper(Cu)-based materials with high thermal conductivity and good stability at high temperatures were developed by adding a small amount of titanium, which has a low enthalpy of alloy formation with C and Cu. The isotropic fine-grained nuclear grade graphite and felt type C/C composite, which were impregnated by Cu and titanium, provided 1.3 times higher thermal conductivity at 1200 K than the original carbon materials. Microstructural analysis showed that the increase of thermal conductivity is due to the formation of titanium compounds at the C/Cu interface. These carbon-based materials could be a candidate material for the plasma facing components of fusion devices.

  1. Metalized Nanocellulose Composites as a Feasible Material for Membrane Supports: Design and Applications for Water Treatment.

    PubMed

    Cruz-Tato, Perla; Ortiz-Quiles, Edwin O; Vega-Figueroa, Karlene; Santiago-Martoral, Liz; Flynn, Michael; Díaz-Vázquez, Liz M; Nicolau, Eduardo

    2017-04-04

    Herein, we study the feasibility of using nanocellulose (NC)-based composites with silver and platinum nanoparticles as additive materials to fabricate the support layer of thin film composite (TFC) membranes for water purification applications. In brief, the NC surface was chemically modified and then was decorated with silver and platinum nanoparticles, respectively, by chemical reduction. These metalized nanocellulose composites (MNC) were characterized by several techniques including: FTIR, XPS, TGA, XRD, and XANES to probe their integrity. Thereafter, we fabricated the MNC-TFC membranes and the support layer was modified to improve the membrane properties. The membranes were thoroughly characterized, and the performance was evaluated in forward osmosis (FO) mode with various feed solutions: nanopure water, urea, and wastewater samples. The fabricated membranes exhibited finger-like pore morphologies and varying pore sizes. Interestingly, higher water fluxes and solute rejection was obtained with the MNC-TFC membranes with wastewater samples. The overall approach of this work provides an effort to fabricated membranes with high water flux and enhanced selectivity.

  2. High temperature support apparatus and method of use for casting materials

    DOEpatents

    Clark, Roger F; Cliber, James A; Stoddard, Nathan G; Gerber, Jesse I; Roberts, Raymond J; Wilmerton, Mark A

    2015-02-10

    This invention relates to a system and a method of use for large ceramic member support and manipulation at elevated temperatures in non-oxidizing atmospheres, such as using carbon-carbon composite materials for producing high purity silicon in the manufacture of solar modules. The high temperature apparatus of this invention includes one or more support ribs, one or more cross braces in combination with the one or more support ribs, and a shaped support liner positionable upon the one or more support ribs and the one or more cross braces.

  3. The Contribution of Social Support to the Material Well-Being of Low-Income Families

    ERIC Educational Resources Information Center

    Henly, Julia R.; Danziger, Sandra K.; Offer, Shira

    2005-01-01

    We hypothesize that the social support available from low-income networks serves primarily a coping function, rather than a leverage function. Social support and its relationship to material well-being is assessed in a sample of 632 former and current welfare recipients. Respondents report higher levels of perceived emotional, instrumental, and…

  4. Using Educative Curriculum Materials to Support the Development of Prospective Teachers' Knowledge

    ERIC Educational Resources Information Center

    Drake, Corey; Land, Tonia J.; Tyminski, Andrew M.

    2014-01-01

    Building on the work of Ball and Cohen and that of Davis and Krajcik, as well as more recent research related to teacher learning from and about curriculum materials, we seek to answer the question, How can prospective teachers (PTs) learn to read and use educative curriculum materials in ways that support them in acquiring the knowledge needed…

  5. Selectability of Print Materials in Support of the Grades 10 and 11 Social Studies Curriculum.

    ERIC Educational Resources Information Center

    Yearwood, D. B.; Yearwood, E. I.

    This project report critiques library print materials used to support grades 10 and 11 social studies curriculum in British Columbia. The data collected are intended to provide a ready reference for school librarians when considering the particular print materials listed. Four criteria were used: readability, format and style, organization, and…

  6. Authentic Materials and the Role of Fixed Support in Language Teaching: Towards a Manual for Language Learners. CLCS Occasional Paper No. 20.

    ERIC Educational Resources Information Center

    Little, D. G.; Singleton, D. M.

    While there are powerful arguments in favor of using authentic, essentially ephemeral materials in second language learning, there may also be a significant need for fixed support in addition. Recent research in Ireland suggests a student-perceived need for instruction in grammar that, in combination with authentic materials and other kinds of…

  7. Controlling cell-material interactions with polymer nanocomposites by use of surface modifying additives

    NASA Astrophysics Data System (ADS)

    Poole-Warren, L. A.; Farrugia, B.; Fong, N.; Hume, E.; Simmons, A.

    2008-11-01

    Polymer nanocomposites (NC) are fabricated by incorporating well dispersed nanoscale particles within a polymer matrix. This study focuses on elastomeric polyurethane (PU) based nanocomposites, containing organically modified silicates (OMS), as bioactive materials. Nanocomposites incorporating chlorhexidine diacetate as an organic modifier (OM) were demonstrated to be antibacterial with a dose dependence related to both the silicate loading and the loading of OM. When the non-antibacterial OM dodecylamine was used, both cell and platelet adhesion were decreased on the nanocomposite surface. These results suggest that OM is released from the polymer and can impact on cell behaviour at the interface. Nanocomposites have potential use as bioactive materials in a range of biomedical applications.

  8. Additivity of kinetic and potential energy contributions in modification of graphene supported on SiO2

    NASA Astrophysics Data System (ADS)

    Zhang, Xitong; Zhao, Shijun; Wang, Yuyu; Xue, Jianming

    2017-04-01

    The damage production induced by MeV highly charged ions (HCI) irradiations in graphene supported on a SiO2 substrate is investigated using molecular dynamics method. We get results in agreement with our recent experiments. We find that the electronic energy loss and potential energy deposition have similar effects on the defects creation in SiO2 substrate-supported graphene and both mechanisms of energy deposition seem to contribute in an additive way. The influences of the energy deposition depth and radius are studied. Only the energy deposited below the surface within 2.5 nm will induce the damage in graphene. Hence, the HCI can be a powerful tool to induce defects in graphene without causing deep damage of the substrate. When charge of incident Xeq+ is above 30, a nanopore is formed and the size of nanopore in graphene can be controlled by changing the incident charge state.

  9. Metallic sulfide additives for positive electrode material within a secondary electrochemical cell

    DOEpatents

    Walsh, William J.; McPheeters, Charles C.; Yao, Neng-ping; Koura, Kobuyuki

    1976-01-01

    An improved active material for use within the positive electrode of a secondary electrochemical cell includes a mixture of iron disulfide and a sulfide of a polyvalent metal. Various metal sulfides, particularly sulfides of cobalt, nickel, copper, cerium and manganese, are added in minor weight proportion in respect to iron disulfide for improving the electrode performance and reducing current collector requirements.

  10. Hydrogen storage material and process using graphite additive with metal-doped complex hydrides

    DOEpatents

    Zidan, Ragaiy; Ritter, James A.; Ebner, Armin D.; Wang, Jun; Holland, Charles E.

    2008-06-10

    A hydrogen storage material having improved hydrogen absorbtion and desorption kinetics is provided by adding graphite to a complex hydride such as a metal-doped alanate, i.e., NaAlH.sub.4. The incorporation of graphite into the complex hydride significantly enhances the rate of hydrogen absorbtion and desorption and lowers the desorption temperature needed to release stored hydrogen.

  11. Interoperability of Materials Database Systems in Support of Nuclear Energy Development and Potential Applications for Fuel Cell Material Selection

    DOE PAGES

    Lin, Lianshan; Austin, Timothy; Ren, Weiju

    2015-01-01

    Materials database interoperability has been of great interest in recent years for information exchange in support of research and development (R&D). In response to data and knowledge sharing needs of the GenIV International Forum (GIF) for global collaboration in nuclear energy R&D, the European Commission JRC Institute for Energy and Transport (JRC-IET) and the Oak Ridge National Laboratory (ORNL) have established a materials database interoperability project that develops techniques for automated materials data exchange between systems hosted at the two institutes MatDB Online at JRC IET and the Gen IV Materials Handbook at ORNL, respectively. The work to enable automatedmore » exchange of data between the two systems leverages the XML data import and export functionalities of both systems in combination with recently developed standards for engineering materials data. The preliminary results of data communication between the two systems have demonstrated the feasibility and efficiency of materials database interoperability, which constructs an interoperation framework that can be seamlessly integrated into the high-throughput First Principles material databases and thus advance the discovery of novel materials in fuel cell applications.« less

  12. Interoperability of Materials Database Systems in Support of Nuclear Energy Development and Potential Applications for Fuel Cell Material Selection

    SciTech Connect

    Lin, Lianshan; Austin, Timothy; Ren, Weiju

    2015-01-01

    Materials database interoperability has been of great interest in recent years for information exchange in support of research and development (R&D). In response to data and knowledge sharing needs of the GenIV International Forum (GIF) for global collaboration in nuclear energy R&D, the European Commission JRC Institute for Energy and Transport (JRC-IET) and the Oak Ridge National Laboratory (ORNL) have established a materials database interoperability project that develops techniques for automated materials data exchange between systems hosted at the two institutes MatDB Online at JRC IET and the Gen IV Materials Handbook at ORNL, respectively. The work to enable automated exchange of data between the two systems leverages the XML data import and export functionalities of both systems in combination with recently developed standards for engineering materials data. The preliminary results of data communication between the two systems have demonstrated the feasibility and efficiency of materials database interoperability, which constructs an interoperation framework that can be seamlessly integrated into the high-throughput First Principles material databases and thus advance the discovery of novel materials in fuel cell applications.

  13. Materials management FY 1995 site support program plan WBS 6.10.7

    SciTech Connect

    Dahlin, E.C.

    1994-09-01

    The Work Breakdown Structure is tabulated for the six main activities within the materials management site support program. Materials Management involves the receipt, storage, issuance, management and disposition of the government`s physical assets. Property Management involves maintaining acceptable levels of property accountability and proper utilization of government owned property. Warehousing involves the shipping, receiving, storage, issuance, and distribution of materials, parts, components and equipment required to support the ongoing operation of the Hanford Site. Inventory Management maintains appropriate levels of general supplies, spare parts, and essential materials to ensure availability of items required to support site operations is timely and provided at the lowest possible cost. Investment Recovery involves the identification and disposition of assets excess to the needs of the site through redeployment, recycling initiatives, and public sale of surplus property. Property Systems operate, maintain and enhance the development of cost effective data systems to control and administer multi-contractor personal property assets.

  14. TiO2 anode materials for lithium-ion batteries with different morphology and additives

    NASA Astrophysics Data System (ADS)

    Liu, Xiang; Ng, Yip Hang; Leung, Yu Hang; Liu, Fangzhou; Djurišic, Aleksandra B.; Xie, Mao Hai; Chan, Wai Kin

    2014-03-01

    Electrochemical performances of different TiO2 nanostructures, TiO2/CNT composite and TiO2 with titanium isopropoxide (TTIP) treatment anode were investigated. For different TiO2 nanostructures, we investigated vertically aligned TiO2 nanotubes on Ti foil and TiO2 nanotube-powders fabricated by rapid breakdown anodization technique. The morphology of the prepared samples was characterized by scanning probe microscopy (SEM). The electrochemical lithium storage abilities were studied by galvanostatic method. In addition, carbon nanotubes (CNT) additives and solution treatment process of TiO2 anode were investigated, and the results show that the additives and treatment could enhance the cycling performance of the TiO2 anode on lithium ion batteries.

  15. A review on graphite and hybrid nano-materials as lubricant additives

    NASA Astrophysics Data System (ADS)

    Anand, Gautam; Saxena, Prateek

    2016-09-01

    The paper presents a review on use of nano-particles as lubricant additives. Nanoparticles have a strong potential to improve the lubrication property of grease when they are used as additives. Nano-grease has several advantages such as improved frictional behaviour, high load bearing capacity and reduced wear, as compared to base oil grease. Current advancements, limitations and challenges in use of nano-grease as a lubricant are discussed. Although, nanogrease has shown outstanding results, more research is required in this field for the commercialization of technology related to nano-grease.

  16. Instrumentation Acquisition for Research and Education in Additive Manufacturing and Advanced Material Fabrication

    DTIC Science & Technology

    2015-08-18

    Triangle Park, NC 27709-2211 Final Report, Instrument acquisition, Selective Laser Melting REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT...Description 1 Renishaw AM 250 Selective Laser Melting Machine Renishaw $585,305 This vendor was selected for purchase due to lower acquisition... selective laser melting of Tefenol – D giant magnetostricitve material. Terfenol‐D has the advantage of achieving magnetostriction comparable

  17. Supporting Infrastructure and Acceptability Issues for Materials Used in New Generation Vehicles

    SciTech Connect

    Das, S.; Curlee, T.R.; Jones, D.W.; Leiby, P.E.; Rubin, J.D.; Schexnayder, S.M.; Vogt, D.P.; Wolfe, A.K.

    1999-03-01

    To achieve its goal of producing vehicles that use two thirds less fuel than current vehicles, the Partnership of a New Generation of Vehicles (PNGV) is designing vehicles that will use lightweight materials in place of heavier materials used in current vehicles. using new materials in automobiles will require the development of a supporting infrastructure to produce both the substitute materials and the components of the substitute materials, as well as the automotive parts constructed from the new materials. This report documents a set of analyses that attempt to identify potential barriers--economic, infrastructure, and public acceptance barriers--to the materials substitution in New Generation Vehicles. The analyses rely on hypothetical vehicle market penetration scenarios and material composition. The approach is comprehensive, examining issues ranging from materials availability to their eventual disposition and its effect on the automobile recycling industry, and from supporting industries' capacity to the public acceptability of these vehicles. The analyses focus on two likely substitute materials, aluminum and glass-reinforced polymer composites.

  18. Thermodynamic method of calculating the effect of alloying additives on interphase interaction in composite materials

    NASA Technical Reports Server (NTRS)

    Tuchinsky, L. I.

    1986-01-01

    The effect of alloying additives to the matrix of a composite on the high temperature solubility rate of a single component fiber was analyzed thermodynamically. With an example of binary Ni alloys, with Group IV-VI transition metals reinforced with W fibers, agreement between the calculated and experimental data was demonstrated.

  19. Does the Use of Diamond-Like Carbon Coating and Organophosphate Lubricant Additive Together Cause Excessive Tribochemical Material Removal?

    SciTech Connect

    Zhou, Yan; Leonard, Donovan N.; Meyer, Harry M.; Luo, Huimin; Qu, Jun

    2015-08-22

    We observe unexpected wear increase on a steel surface that rubbed against diamond-like carbon (DLC) coatings only when lubricated by phosphate-based antiwear additives. Contrary to the literature hypothesis of a competition between zinc dialkyldithiophosphate produced tribofilms and DLC-induced carbon transfer, here a new wear mechanism based on carbon-catalyzed tribochemical interactions supported by surface characterization is proposed

  20. Mathematical Models for the Education Sector, Supporting Material to the Survey. (Les Modeles Mathematiques du Secteur Enseignement. Annexes.) Technical Report.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France).

    This document contains supporting material for the survey on current practice in the construction and use of mathematical models for education. Two kinds of supporting material are included: (1) the responses to the questionnaire, and (2) supporting documents and other materials concerning the mathematical model-building effort in education.…

  1. Magnetic Properties of FeNi-Based Thin Film Materials with Different Additives.

    PubMed

    Liang, Cai; Gooneratne, Chinthaka P; Wang, Qing Xiao; Liu, Yang; Gianchandani, Yogesh; Kosel, Jurgen

    2014-09-01

    This paper presents a study of FeNi-based thin film materials deposited with Mo, Al and B using a co-sputtering process. The existence of soft magnetic properties in combination with strong magneto-mechanical coupling makes these materials attractive for sensor applications. Our findings show that FeNi deposited with Mo or Al yields magnetically soft materials and that depositing with B further increases the softness. The out-of-plane magnetic anisotropy of FeNi thin films is reduced by depositing with Al and completely removed by depositing with B. The effect of depositing with Mo is dependent on the Mo concentration. The coercivity of FeNiMo and FeNiAl is reduced to less than a half of that of FeNi, and a value as low as 40 A/m is obtained for FeNiB. The surfaces of the obtained FeNiMo, FeNiAl and FeNiB thin films reveal very different morphologies. The surface of FeNiMo shows nano-cracks, while the FeNiAl films show large clusters and fewer nano-cracks. When FeNi is deposited with B, a very smooth morphology is obtained. The crystal structure of FeNiMo strongly depends on the depositant concentration and changes into an amorphous structure at a higher Mo level. FeNiAl thin films remain polycrystalline, even at a very high concentration of Al, and FeNiB films are amorphous, even at a very low concentration of B.

  2. Magnetic Properties of FeNi-Based Thin Film Materials with Different Additives

    PubMed Central

    Liang, Cai; Gooneratne, Chinthaka P.; Wang, Qing Xiao; Liu, Yang; Gianchandani, Yogesh; Kosel, Jurgen

    2014-01-01

    This paper presents a study of FeNi-based thin film materials deposited with Mo, Al and B using a co-sputtering process. The existence of soft magnetic properties in combination with strong magneto-mechanical coupling makes these materials attractive for sensor applications. Our findings show that FeNi deposited with Mo or Al yields magnetically soft materials and that depositing with B further increases the softness. The out-of-plane magnetic anisotropy of FeNi thin films is reduced by depositing with Al and completely removed by depositing with B. The effect of depositing with Mo is dependent on the Mo concentration. The coercivity of FeNiMo and FeNiAl is reduced to less than a half of that of FeNi, and a value as low as 40 A/m is obtained for FeNiB. The surfaces of the obtained FeNiMo, FeNiAl and FeNiB thin films reveal very different morphologies. The surface of FeNiMo shows nano-cracks, while the FeNiAl films show large clusters and fewer nano-cracks. When FeNi is deposited with B, a very smooth morphology is obtained. The crystal structure of FeNiMo strongly depends on the depositant concentration and changes into an amorphous structure at a higher Mo level. FeNiAl thin films remain polycrystalline, even at a very high concentration of Al, and FeNiB films are amorphous, even at a very low concentration of B. PMID:25587418

  3. Controlling the Electrostatic Discharge Ignition Sensitivity of Composite Energetic Materials Using Carbon Nanotube Additives

    SciTech Connect

    Kade H. Poper; Eric S. Collins; Michelle L. Pantoya; Michael Daniels

    2014-10-01

    Powder energetic materials are highly sensitive to electrostatic discharge (ESD) ignition. This study shows that small concentrations of carbon nanotubes (CNT) added to the highly reactive mixture of aluminum and copper oxide (Al + CuO) significantly reduces ESD ignition sensitivity. CNT act as a conduit for electric energy, bypassing energy buildup and desensitizing the mixture to ESD ignition. The lowest CNT concentration needed to desensitize ignition is 3.8 vol.% corresponding to percolation corresponding to an electrical conductivity of 0.04 S/cm. Conversely, added CNT increased Al + CuO thermal ignition sensitivity to a hot wire igniter.

  4. Does the addition of proteases affect the biogas yield from organic material in anaerobic digestion?

    PubMed

    Müller, Liane; Kretzschmar, Jörg; Pröter, Jürgen; Liebetrau, Jan; Nelles, Michael; Scholwin, Frank

    2016-03-01

    The aim of this study was to investigate the biochemical disintegration effect of hydrolytic enzymes in lab scale experiments. Influences of enzyme addition on the biogas yield as well as effects on the process stability were examined. The addition of proteases occurred with low and high dosages in batch and semi-continuous biogas tests. The feed mixture consisted of maize silage, chicken dung and cow manure. Only very high concentrated enzymes caused an increase in biogas production in batch experiments. In semi-continuous biogas tests no positive long-term effects (100 days) were observed. Higher enzyme-dosage led to a reduced biogas-yield (13% and 36% lower than the reference). Phenylacetate and -propionate increased (up to 372 mgl(-1)) before the other volatile fatty acids did. Volatile organic acids rose up to 6.8 gl(-1). The anaerobic digestion process was inhibited.

  5. Density functional calculations in the automotive industry: Catalyst supports and hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Wolverton, Christopher

    2006-03-01

    In my talk, I will describe some uses of density functional theory (DFT) calculations in the research laboratory at Ford, and particularly highlight work that was inspired by, or performed in collaboration with Ken Hass. I begin with a discussion of past work on γ-Al2O3 catalyst support materials, but also discuss the current main focus of our group's activities: hydrogen storage materials. Catalyst Supports: In current three-way automotive catalysts, precious metals are often supported by the phase of aluminum oxide known as γ-Al2O3. Despite the ubiquitous nature of this oxide in current automobile catalysts, and a considerable amount of effort expended to understand this material, many questions about the phase stability and even crystal structure of γ-Al2O3 remain. DFT calculations have made significant progress in unraveling these unanswered questions, allowing one to construct realistic models of the supported catalysts materials. Hydrogen Storage Materials: One of the major bottlenecks to the widespread use of hydrogen-fueled vehicles is the ability to store sufficient energy on-board to enable vehicle attributes acceptable to customers. I will give a general introduction to the topic of hydrogen storage, and a broad survey of the various classes of hydrogen storage technologies, and point out some pros and cons associated with each class. Currently known technologies have insufficient usable energy densities, and I will describe how DFT calculations are aiding the search for improved high density storage materials.

  6. Reduction of CO2 diffuse emissions from the traditional ceramic industry by the addition of Si-Al raw material.

    PubMed

    González, I; Barba-Brioso, C; Campos, P; Romero, A; Galán, E

    2016-09-15

    The fabrication of ceramics can produce the emission of several gases, denominated exhaust gases, and also vapours resulting from firing processes, which usually contain metals and toxic substances affecting the environment and the health of workers. Especially harmful are the diffuse emissions of CO2, fluorine, chlorine and sulphur from the ceramics industry, which, in highly industrialized areas, can suppose an important emission focus of dangerous effects. Concerning CO2, factories that use carbonate-rich raw materials (>30% carbonates) can emit high concentrations of CO2 to the atmosphere. Thus, carbonate reduction or substitution with other raw materials would reduce the emissions. In this contribution, we propose the addition of Al-shales to the carbonated ceramic materials (marls) for CO2 emission reduction, also improving the quality of the products. The employed shales are inexpensive materials of large reserves in SW-Spain. The ceramic bodies prepared with the addition of selected Al-shale to marls in variable proportions resulted in a 40%-65% CO2 emission reduction. In addition, this research underlines at the same time that the use of a low-price raw material can also contribute to obtaining products with higher added value.

  7. Magnetic Force Microscopy Study of Zr2Co11 -Based Nanocrystalline Materials: Effect of Mo Addition

    DOE PAGES

    Yue, Lanping; Jin, Yunlong; Zhang, Wenyong; ...

    2015-01-01

    Tmore » he addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. he effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox(x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. he coercivity of the samples increases with the increase in Mo content (x≤1.5). he maximum energy product(BH)maxincreases with increasingxfrom 0.5 MGOe forx=0to a maximum value of 4.2 MGOe forx=1.5. he smallest domain size with a relatively short magnetic correlation length of 128 nm and largest root-mean-square phase shiftΦrmsvalue of 0.66° are observed for thex=1.5. he optimal Mo addition promotes magnetic domain structure refinement and thus leads to a significant increase in coercivity and energy product in this sample.« less

  8. Survey of residue levels of organic solvents in "existing food additives" and health food materials by head-space GC.

    PubMed

    Uematsu, Yoko; Ogimoto, Mami; Suzuki, Kumi; Kabashima, Junichirou; Ito, Koichi; Nakazato, Mitsuo

    2008-01-01

    Organic solvent residue levels in "Existing Food Additives" (n=145), health food materials (n=23), and commercial health food products (n=19) were surveyed. Ethanol was the dominant solvent found in the samples, suggesting its use in the manufacturing process. Methanol, acetone, 2-propanol and ethyl acetate was also found. No residual solvent exceeded the limits set by the Food Sanitation Law.

  9. Materials and Additive Manufacturing for Energy Efficiency in Wind Turbine and Aircraft Industries

    SciTech Connect

    Datskos, Panos G; Polyzos, Georgios; Clemons, Art; Bolton, Paul; Hollander, Aaron

    2016-05-04

    The purpose of this project was to develop surface treatments which will inhibit the formation of ice on turbine blades and propellers. ORNL worked with Piedmont Propulsion Systems, LLC and First Aviation Services Inc. to demonstrate a new surface treatment for two primary markets, aviation and wind turbines, as well as secondary markets such as power lines, bridges, boats, roofs and antennas among others. Exploring alternative surface treatments for wind turbines will provide anti-icing properties and erosion/abrasion prevention properties similar to those for aviation applications. A series of superhydrophobic coating materials was synthesized and successfully applied on anti-ice tape materials that could be used in a wide range of wind turbine and aviation applications to prevent ice accumulation. The coatings developed in this project were based on superhydrophobic particles of different geometries and sizes that were homogeneously dispersed in polymeric binders. The superhydrophobic features of the coatings are volumetric and their abrasion resistance was evaluated. Future research will involve the demonstration of anti-icing properties of the surface treatment developed in this project.

  10. Degradation mechanisms of carbon-based electrocatalyst support materials and development of an advanced support based on electrically conducting diamond

    NASA Astrophysics Data System (ADS)

    Fischer, Anne Elizabeth

    2005-11-01

    In this dissertation, the degradation mechanisms of sp 2-bonded carbon electrocatalyst supports were studied under potential and temperature conditions relevant to the polymer electrolyte membrane fuel cell (PEMFC). In addition, an alternative support was fabricated in two forms: electrically conducting diamond powder and paper to overcome current material stability issues in the PEMFC. Two structurally well-characterized sp2-bonded carbon powders, graphite (structurally well-ordered) and glassy carbon (GC, structurally disordered) were studied under potentiostatic polarization from 1.0 to 1.6 V vs. Ag/AgCl at 25, 50, and 80°C. Characterization of the surface oxidation and microstructural changes (i.e., increase in the exposed edge plane density) provided evidence for the so-called order/disorder mechanism where structurally disordered carbons corrode more severely because of oxidation and gasification of the exposed edge plane. Microstructural changes for graphite were heterogeneously distributed across the electrode surface. This is indicative of a nucleation and growth process, where disordered regions and defects serve as active sites for electrochemical corrosion, while other, more structurally ordered regions do not corrode. Preliminary results for a high-surface-area carbon black, Vulcan XC-72, are presented that show changes in the surface oxide content and also discuss the effect of polarization potential on Pt activity. The physical and electrochemical properties of two commercial boron-doped diamond thin-film electrodes were compared with microcrystalline and nanocrystalline boron-doped diamond thin film deposited in our laboratory. The electrochemical response for Fe(CN)63-/4-, Ru(NH3)6 3+/2+, IrCl62-/3-, 4-methylcatechol, and Fe3+/2+ was quite reproducible from electrode type-to-type and from film-to-film for a given type. DeltaEp, ipox, and ip red values for Fe(CN)63-/4-, Ru(NH 3)63+/2+ on all electrodes were relatively unaffected by pH. Electrically

  11. An exploration of how pre-service early childhood teachers use educative curriculum materials to support their science teaching practices

    NASA Astrophysics Data System (ADS)

    Englehart, Deirdre

    young children and how children communicate their findings. Young children need support in their participation of inquiry learning. Successful implementation of guided inquiry practices occurred in this research. Also, the teachers in this research found insightful ways that directly supported young children in their communication of ideas. Implications for further research are also discussed. Educative materials could further support pre-service early childhood teachers if additional supports were used including accessible curricular rationales, support in classroom management and the specific use of guided inquiry.

  12. The effect of the addition of different fibres on the transverse and impact strength of acrylic resin denture base material.

    PubMed

    Rahamneh, A; Jagger, D C; Harrison, A

    2003-06-01

    The aim of the present study was to investigate the effect of the addition of different types of fibres on the transverse and impact strength of acrylic resin denture base material. The addition of glass fibres (strand) and polyethylene fibres produced a non significant increase in the modulus of elasticity, compared with the control of conventional heat-cured acrylic resin. The addition of glass fibres (woven and strand), polyethylene and carbon fibres to acrylic resin produced a non significant increase in the modulus of rupture. The addition of carbon, glass (strand) and polyethylene fibres produced a significant increase in the impact strength. Within the limitations of this study the addition of silk fibres did not produce an improvement in the mechanical properties.

  13. Carbon nanocages: a new support material for Pt catalyst with remarkably high durability.

    PubMed

    Wang, Xiao Xia; Tan, Zhe Hua; Zeng, Min; Wang, Jian Nong

    2014-03-24

    Low durability is the major challenge hindering the large-scale implementation of proton exchange membrane fuel cell (PEMFC) technology, and corrosion of carbon support materials of current catalysts is the main cause. Here, we describe the finding of remarkably high durability with the use of a novel support material. This material is based on hollow carbon nanocages developed with a high degree of graphitization and concurrent nitrogen doping for oxidation resistance enhancement, uniform deposition of fine Pt particles, and strong Pt-support interaction. Accelerated degradation testing shows that such designed catalyst possesses a superior electrochemical activity and long-term stability for both hydrogen oxidation and oxygen reduction relative to industry benchmarks of current catalysts. Further testing under conditions of practical fuel cell operation reveals almost no degradation over long-term cycling. Such a catalyst of high activity, particularly, high durability, opens the door for the next-generation PEMFC for "real world" application.

  14. Carbon nanocages: A new support material for Pt catalyst with remarkably high durability

    PubMed Central

    Wang, Xiao Xia; Tan, Zhe Hua; Zeng, Min; Wang, Jian Nong

    2014-01-01

    Low durability is the major challenge hindering the large-scale implementation of proton exchange membrane fuel cell (PEMFC) technology, and corrosion of carbon support materials of current catalysts is the main cause. Here, we describe the finding of remarkably high durability with the use of a novel support material. This material is based on hollow carbon nanocages developed with a high degree of graphitization and concurrent nitrogen doping for oxidation resistance enhancement, uniform deposition of fine Pt particles, and strong Pt-support interaction. Accelerated degradation testing shows that such designed catalyst possesses a superior electrochemical activity and long-term stability for both hydrogen oxidation and oxygen reduction relative to industry benchmarks of current catalysts. Further testing under conditions of practical fuel cell operation reveals almost no degradation over long-term cycling. Such a catalyst of high activity, particularly, high durability, opens the door for the next-generation PEMFC for “real world” application. PMID:24658614

  15. Carbon nanocages: A new support material for Pt catalyst with remarkably high durability

    NASA Astrophysics Data System (ADS)

    Wang, Xiao Xia; Tan, Zhe Hua; Zeng, Min; Wang, Jian Nong

    2014-03-01

    Low durability is the major challenge hindering the large-scale implementation of proton exchange membrane fuel cell (PEMFC) technology, and corrosion of carbon support materials of current catalysts is the main cause. Here, we describe the finding of remarkably high durability with the use of a novel support material. This material is based on hollow carbon nanocages developed with a high degree of graphitization and concurrent nitrogen doping for oxidation resistance enhancement, uniform deposition of fine Pt particles, and strong Pt-support interaction. Accelerated degradation testing shows that such designed catalyst possesses a superior electrochemical activity and long-term stability for both hydrogen oxidation and oxygen reduction relative to industry benchmarks of current catalysts. Further testing under conditions of practical fuel cell operation reveals almost no degradation over long-term cycling. Such a catalyst of high activity, particularly, high durability, opens the door for the next-generation PEMFC for ``real world'' application.

  16. Composite materials based on high-modulus compounds for additive technology

    NASA Astrophysics Data System (ADS)

    Grigoriev, M.; Kotelnikov, N.; Buyakova, S.; Kulkov, S.

    2016-07-01

    The effect of adding nanocrystalline ZrO2 and submicron TiC to ultrafine Al2O3 on mechanical properties and the microstructure of the composites developed by hot pressing was investigated. It was shown that by means of hot pressing in argon atmosphere at the sintering temperature of 1500 °C one can obtain the composites of Al2O3-ZrO2-TiC with a fine structure and minimal porosity. It was shown that in the material a multi-scale hierarchical structure is formed, which possesses high physical and mechanical properties: the hardness and fracture toughness was 22 GPa and 5.2 MPa*m1/2, respectively. It has been shown that mechanical properties of the composite are better than those of commercial composites based on aluminum oxide (Al2O3, ZTA, Al2O3-TiC) and are comparable to those of silicon nitride.

  17. Feasibility Study on 3-D Printing of Metallic Structural Materials with Robotized Laser-Based Metal Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Ding, Yaoyu; Kovacevic, Radovan

    2016-07-01

    Metallic structural materials continue to open new avenues in achieving exotic mechanical properties that are naturally unavailable. They hold great potential in developing novel products in diverse industries such as the automotive, aerospace, biomedical, oil and gas, and defense. Currently, the use of metallic structural materials in industry is still limited because of difficulties in their manufacturing. This article studied the feasibility of printing metallic structural materials with robotized laser-based metal additive manufacturing (RLMAM). In this study, two metallic structural materials characterized by an enlarged positive Poisson's ratio and a negative Poisson's ratio were designed and simulated, respectively. An RLMAM system developed at the Research Center for Advanced Manufacturing of Southern Methodist University was used to print them. The results of the tensile tests indicated that the printed samples successfully achieved the corresponding mechanical properties.

  18. A Metallurgical Evaluation of the Powder-Bed Laser Additive Manufactured 4140 Steel Material

    NASA Astrophysics Data System (ADS)

    Wang, Wesley; Kelly, Shawn

    2016-03-01

    Using laser powder bed fusion (PBF-L) additive manufacturing (AM) process for steel or iron powder has been attempted for decades. This work used a medium carbon steel (AISI 4140) powder to explore the feasibility of AM. The high carbon equivalent of 4140 steel (CEIIW ≈ 0.83) has a strong tendency toward cold cracking. As such, the process parameters must be carefully controlled to ensure the AM build quality. Through an orthogonally designed experimental matrix, a laser-welding procedure was successfully developed to produce 4140 steel AM builds with no welding defects. In addition, the microstructure and micro-cleanliness of the as-welded PBF-L AM builds were also examined. The results showed an ultra-fine martensite lath structure and an ultra-clean internal quality with minimal oxide inclusion distribution. After optimizing the PBF-L AM process parameters, including the laser power and scan speed, the as-welded AM builds yielded an average tensile strength higher than 1482 MPa and an average 33 J Charpy V-notch impact toughness at -18°C. The surface quality, tensile strength, and Charpy V-notch impact toughness of AM builds were comparable to the wrought 4140 steel. The excellent mechanical properties of 4140 steel builds created by the PBF-L AM AM process make industrial production more feasible, which shows great potential for application in the aerospace, automobile, and machinery industries.

  19. Nano-ceramic support materials for low temperature fuel cell catalysts

    NASA Astrophysics Data System (ADS)

    Lv, Haifeng; Mu, Shichun

    2014-04-01

    Low temperature fuel cells (LTFCs) have received broad attention due to their low operating temperature, virtually zero emissions, high power density and efficiency. However, the limited stability of the catalysts is a critical limitation to the large scale commercialization of LTFCs. State of the art carbon supports undergo corrosion under harsh chemical and electrochemical oxidation conditions, which results in performance degradation of catalysts. Therefore, non-carbon materials which are highly oxidation resistant under strongly oxidizing conditions of LTFCs are ideal alternative supports. This minireview highlights the advances and scenarios in using nano-ceramics as supports to enhance the stability of catalysts, the solutions to improve electrical conductivity of nano-ceramic materials, and the synergistic effects between metal catalyst and support to help improve the catalytic activity and CO/SO2 tolerance of catalysts.

  20. Nano-ceramic support materials for low temperature fuel cell catalysts.

    PubMed

    Lv, Haifeng; Mu, Shichun

    2014-05-21

    Low temperature fuel cells (LTFCs) have received broad attention due to their low operating temperature, virtually zero emissions, high power density and efficiency. However, the limited stability of the catalysts is a critical limitation to the large scale commercialization of LTFCs. State of the art carbon supports undergo corrosion under harsh chemical and electrochemical oxidation conditions, which results in performance degradation of catalysts. Therefore, non-carbon materials which are highly oxidation resistant under strongly oxidizing conditions of LTFCs are ideal alternative supports. This minireview highlights the advances and scenarios in using nano-ceramics as supports to enhance the stability of catalysts, the solutions to improve electrical conductivity of nano-ceramic materials, and the synergistic effects between metal catalyst and support to help improve the catalytic activity and CO/SO2 tolerance of catalysts.

  1. Clinoptilolite: a possible support material for nitrifying biofilms for effective control of ammonium effluent quality?

    PubMed

    Inan, H; Beler Baykal, B

    2005-01-01

    Ammonium selective natural zeolite clinoptilolite is suggested as a possible support material for nitrifying biofilms to help improve effluent ammonium quality through its high capacity of ammonium removal in the process of ion exchange. This will especially be helpful in cases where the biofilter receives peak or variable loads routinely or occasionally. At the time of peak loads or shocks of ammonium, ion exchange capacity will provide a buffer for the effluent ammonium quality. Data to support this suggestion is presented.

  2. Study on Friction and Wear Properties of Silver Matrix Brush Material with Different Additives

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoli; Wang, Wenfang; Hong, Yu; Wu, Yucheng

    2013-07-01

    Friction and wear processes of AgCuX (G, CF and AlN) composites-CuAgV alloy friction pair and effects of different additive content in silver based composite on friction and wear behavior are studied in this paper. The microstructure of the brush wear surface is observed by SEM. The results show that when graphite content is up to 9 wt.%, Ag-Cu-CF-G composite exhibits the best wear properties; when the content of aluminum nitride is up to 0.5 wt.%, Ag-Cu-AlN-G composites has the most comprehensive performance. The wear loss of both composites arises with the increase of both pressure and speed, but when speed reaches a critical value, the increased amplitude of wear loss tends to be steady.

  3. Heat transfer and material flow during laser assisted multi-layer additive manufacturing

    SciTech Connect

    Manvatkar, V.; De, A.; DebRoy, T.

    2014-09-28

    A three-dimensional, transient, heat transfer, and fluid flow model is developed for the laser assisted multilayer additive manufacturing process with coaxially fed austenitic stainless steel powder. Heat transfer between the laser beam and the powder particles is considered both during their flight between the nozzle and the growth surface and after they deposit on the surface. The geometry of the build layer obtained from independent experiments is compared with that obtained from the model. The spatial variation of melt geometry, cooling rate, and peak temperatures is examined in various layers. The computed cooling rates and solidification parameters are used to estimate the cell spacings and hardness in various layers of the structure. Good agreement is achieved between the computed geometry, cell spacings, and hardness with the corresponding independent experimental results.

  4. Data collection handbook to support modeling the impacts of radioactive material in soil

    SciTech Connect

    Yu, C.; Cheng, J.J.; Jones, L.G.; Wang, Y.Y.; Faillace, E.; Loureiro, C.; Chia, Y.P.

    1993-04-01

    A pathway analysis computer code called RESRAD has been developed for implementing US Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), and material-related (soil, concrete) parameters are used in the RESRAD code. This handbook discusses parameter definitions, typical ranges, variations, measurement methodologies, and input screen locations. Although this handbook was developed primarily to support the application of RESRAD, the discussions and values are valid for other model applications.

  5. The capability of satellite borne remote sensors to measure stratospheric trace constituents. Volume 3: Supporting material

    NASA Technical Reports Server (NTRS)

    Keitz, E. L.

    1978-01-01

    Contained in this volume is material of a supportive nature not considered to be of sufficient importance to be included in the other two previous volumes. This material is of two types:(1) information and numerical evaluations used in the development of mission evaluations for stratospheric trace constituent measurement;and (2) various spatial and temporal distributions for those stratospheric trace species having sufficient measurements available to warrant their presentation.

  6. Sail film materials and supporting structure for a solar sail, a preliminary design, volume 4

    NASA Technical Reports Server (NTRS)

    Rowe, W. M. (Editor)

    1978-01-01

    Solar sailing technology was examined in relation to a mission to rendezvous with Halley's Comet. Development of an ultra-light, highly reflecting material system capable of operating at high solar intensity for long periods of time was emphasized. Data resulting from the sail materials study are reported. Topics covered include: basic film; coatings and thermal control; joining and handling; system performance; and supporting structures assessment for the heliogyro.

  7. Standard addition method applied to solid-state stripping voltammetry: determination of zirconium in minerals and ceramic materials.

    PubMed

    Doménech-Carbó, A; Moya-Moreno, M; Doménech-Carbó, M T

    2004-09-01

    An application of the standard addition method to stripping voltammetry of solid materials immobilized in inert electrodes is described. The method allows the determination of the mass fraction of a depositable metal M in a material on addition of known amounts of a standard material containing M to a mixture of that material and a reference compound of a second depositable metal, R. After a reductive deposition step, voltammograms recorded for those modified electrodes immersed in a suitable electrolyte produce stripping peaks for the oxidation of the deposits of M and R. If no intermetallic effects appear the quotients between the peak areas and the peak currents for the stripping oxidation of M and R vary linearly with the mass ratio of the added standard and the reference compound, thus providing an electrochemical method for determining the amount of M in the sample. The method has been applied to the determination of Zr in minerals, ceramic frits, and pigments, using ZnO as reference material and ZrO(2) as the standard.

  8. Identification of trace additives in polymer materials by attenuated total reflection Fourier transform infrared mapping coupled with multivariate curve resolution.

    PubMed

    Li, Qian; Tang, Yongjiao; Yan, Zhiwei; Zhang, Pudun

    2017-03-07

    Although multivariate curve resolution (MCR) has been applied to the analysis of Fourier transform infrared (FTIR) imaging, it is still problematic to determine the number of components. The reported methods at present tend to cause the components of low concentration missed. In this paper a new idea was proposed to resolve this problem. First, MCR calculation was repeated by increasing the number of components sequentially, then each retrieved pure spectrum of as-resulted MCR component was directly compared with a real-world pixel spectrum of the local high concentration in the corresponding MCR map. One component was affirmed only if the characteristic bands of the MCR component had been included in its pixel spectrum. This idea was applied to attenuated total reflection (ATR)/FTIR mapping for identifying the trace additives in blind polymer materials and satisfactory results were acquired. The successful demonstration of this novel approach opens up new possibilities for analyzing additives in polymer materials.

  9. 24 CFR 246.8 - Materials to be submitted to HUD in support of preemption request.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Materials to be submitted to HUD in support of preemption request. 246.8 Section 246.8 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL...

  10. Occupational Health and Safety. Level 1. Level 2. Level 3. Support Materials for Agricultural Training.

    ERIC Educational Resources Information Center

    Batman, Kangan; Gadd, Nick; Lucas, Michele

    This publication contains the three communication skills units of the three levels of Support Materials for Agricultural Training (SMAT) in the area of occupational health and safety: Level 1 (starting), 2 (continuing), and 3 (completing). The units are designed to help the learner improve his or her written and spoken communication skills needed…

  11. Dispositions Supporting Elementary Interns in the Teaching of Reform-Based Science Materials

    ERIC Educational Resources Information Center

    Eick, Charles J.; Stewart, Bethany

    2010-01-01

    Dispositions supporting the teaching of science as structured inquiry by four elementary candidates are presented. Candidates were studied during student teaching based on their positive attitudes toward teaching science with reform-based materials in their methods course. Personal learning histories informed their attitudes, values, and beliefs…

  12. Agricultural Production. Numeracy. Level 1. Level 2. Level 3. Support Materials for Agricultural Training.

    ERIC Educational Resources Information Center

    Batman, Kangan; Tully, Chris

    This publication contains the three numeracy units of the three levels of Support Materials for Agricultural Training (SMAT) in agricultural production: Level 1 (starting), 2 (continuing), and 3 (completing). The units are designed to help the learner improve his or her numeracy skills needed to deal with agricultural production. SMAT materials…

  13. Occupational Health and Safety. Numeracy. Level 1. Level 2. Level 3. Support Materials for Agricultural Training.

    ERIC Educational Resources Information Center

    Batman, Kangan; Tully, Chris

    This publication contains the three numeracy units of the three levels of Support Materials for Agricultural Training (SMAT) in the area of occupational health and safety: Level 1 (starting), 2 (continuing), and 3 (completing). The units are designed to help the learner improve his or her numeracy skills needed to deal with occupational safety and…

  14. Selection of support materials for immobilization of Burkholderia cepacia PCL3 in treatment of carbofuran-contaminated water.

    PubMed

    Laocharoen, S; Plangklang, P; Reungsang, A

    2013-01-01

    This study investigated the utilization of agricultural matrices as the support materials for cell immobilization to improve the technique of bioremediation. Coir, bulrush, banana stem and water hyacinth stem in both delignified and undelignified forms were used to immobilize Burkholderia cepacia PCL3 in bioremediation of carbofuran at 5 mg l(-1) in synthetic wastewater. Undelignified coir was found to be the most suitable support material for cell immobilization, giving the short half-life of carbofuran of 3.40 d (2.8 times shorter than the treatments with free cells). In addition, it could be reused three times without a loss in ability to degrade carbofuran. The growth and degradation ability of free cells were completely inhibited at the initial carbofuran concentrations of 250 mg l(-1), while there was no inhibitory effect of carbofuran on the immobilized cells. The results indicated a great potential for using the agricultural matrices as support material for cell immobilization to improve the overall efficiency of carbofuran bioremediation in contaminated water by B. cepacia PCL3.

  15. Templated synthesis for highly ordered metal/support nanocomposite materials with catalytic applications

    NASA Astrophysics Data System (ADS)

    Sarkar, Jayashri

    Template synthesis is a powerful method of synthesizing materials with tunable properties. Tailorability of the templates makes it a viable method for high performance material synthesis. Surfactant, polymers and semiconductors have been used as templating tools for a long time. In the present work, we demonstrate the ability to synthesize hexagonally organized porous titania, zirconia and zirconia/titania mixed oxide supports and their respective nanocomposites of Pt from their alkoxide precursors using a highly viscous mixed surfactant template, separating nanoscopic bicontinuous channels of water and isooctane. Oil soluble precursor that eventually forms the support, precipitates at the oil-water interface mimicking the microstructure of the template. Subsequent reduction of Pt precursor in the aqueous nanochannels decorates the surface of the macropore walls with well-separated platinum (Pt) nanoparticles. This technique enables us to synthesize two components in a single template system by utilizing both oil and water phases. The composite formed possess a bimodal pore size distribution with one mean pore size ˜3.5nm (nanopores) and the other in the larger mean pore diameter regions ˜100nm-2mum (macropores), depending on the oxide support. Because of the decreased mass transfer resistance provided by the ordered and interconnected macropores in the support, the Pt/TiO2 nanocomposite exhibits a significantly higher carbon monoxide oxidation efficiency than that obtained with a commercial support that has a 4-fold larger specific surface area (at equivalent Pt loadings). We further demonstrate that simple changes in the post-synthesis processing can improve the properties of the material. Altering the drying technique and calcination temperature result in a substantial improvement in the specific surface area of the support material making them better than or comparable to the commercial support materials. We are able to synthesize materials with very low Pt

  16. An additional S-shaped structure for sensitivity improvement of coaxial probe for permittivity determination of low loss materials

    NASA Astrophysics Data System (ADS)

    Jiao, Xingmin; Jin, Wei; Yang, Xiaoqing

    2015-05-01

    Permittivity measurement of materials is important in microwave chemistry, microwave material processing and microwave heating. The open-ended coaxial line method is one of the most popular and effective means for permittivity measurement. However, the conventional coaxial probe has difficulty in distinguishing small permittivity variations for low loss media. In this paper an additional S-shaped structure is proposed for sensitivity improvement of a coaxial probe for permittivity determination of low loss materials at 2.45 GHz. The small permittivity variation can be distinguished due to field enhancement generated by the additional S-shaped structure. We studied the variation of reflection coefficient amplitude for three kinds of samples with different moisture content, within the probe at different insertion depths. We find that the conventional coaxial probe cannot distinguish small permittivity variations until the moisture content of materials reaches 3%. Meanwhile, the probe with the S-shaped structure can detect such small permittivity variations when the moisture content of samples changes by only 1%. The experimental results demonstrate that the new probe proposed in this paper is reliable and feasible.

  17. Dendrimer-modified solid supports: nanostructured materials with potential drug allergy diagnostic applications.

    PubMed

    Ruiz-Sanchez, A J; Montañez, M I; Mayorga, C; Torres, M J; Kehr, N S; Vida, Y; Collado, D; Najera, F; De Cola, L; Perez-Inestrosa, E

    2012-01-01

    Complex functional materials consisting of bioactive molecules immobilized on solid supports present potential applications in biosensoring. Advances in the fabrication of these surface materials are of growing interest for antibody-based diagnosis. This work exploits dendrimers as versatile nanostructures for templating sensor surfaces and the critical role of the immobilization protocol in the solid supports cellulose and zeolites, of organic and inorganic composition respectively. The fabrication and characterization, including the degree of functionalization and reproducibility, of different nanostructured materials are described. To validate the approach, the fabricated supports were further used as a solid phase for developing a radioimmunoassay to detect immunoglobulin E (IgE) specific to penicillin, the antibody involved in immediate allergy responses to this drug. The dendrimer-modified supports provide assays with significantly enhanced sensitivity, as well as increase the availability of biomolecules for specific interaction and minimize nonspecific adsorptions through appropriate functionalization protocols in each case. The manufacturing methodology involved the use of a long, flexible hydrophilic spacer in the cellulose materials, and a higher surface density of the immobilized dendrimers in the zeolite crystals. The ability of hybrid zeolite materials in such biosensing applications was evaluated for the first time. The assays were validated in human serum samples from patients allergic to penicillin and from non-allergic controls. The specificity and improved sensitivity of the dendrimer- modified supports make these strategies versatile for different bioactive molecules and could have significant implications for the quantification of a wide range of specific IgE antibodies and other biomolecules of diagnostic interest.

  18. A combination of vermiculite and paper pulp supporting material for the photoautotrophic micropropagation of sweet potato.

    PubMed

    Afreen-Zobayed; Zobayed; Kubota; Kozai; Hasegawa

    2000-08-22

    A mixture of vermiculite (hydrous silicates) and paper pulp (waste product of paper industry) was used as a supporting material for the in vitro photoautotrophic micropropagation of plantlets. Sweet potato was used as a model plant to find out the appropriate proportion of vermiculite and paper pulp for the optimum growth of the plantlets. The plantlets grown in the conventional supporting material, agar, were used as the control. The study revealed that in all aspects, the plantlets grown in vermiculite mixed with 30% (w/w) paper pulp exhibited the highest growth performance. The shoot and root fresh mass were x2.7 greater than those in agar (control); the leaf, stem and root dry mass were also greater and at least two fold in this treatment compared with those in the control. The net photosynthetic rate per plantlet was highest in this treatment, and on day 20 it was 15.3 µmol CO(2) h(-1) as compared with 9.8 µmol CO(2) h(-1) in the control. The growth of both shoots and roots decreased gradually with the increase or decrease of percentage of paper pulp in the supporting material. In general, the growth was significantly poorer in the plantlets grown in 100% vermiculite than that in vermiculite mixed with 30% paper pulp but still greater than in the control. The porosity of the supporting materials increased with the increase in the percentage of paper pulp in the supporting material. After transplanting to the ex vitro condition the survival percentage did not vary significantly (90-100%) among the treatments, except in control where it was only 73%. The number of unfolded leaves and the stem height were similar among the treatments except those in the control.

  19. Components of yeast (Sacchromyces cervisiae) extract as defined media additives that support the growth and productivity of CHO cells.

    PubMed

    Spearman, Maureen; Chan, Sarah; Jung, Vince; Kowbel, Vanessa; Mendoza, Meg; Miranda, Vivian; Butler, Michael

    2016-09-10

    Yeast and plant hydrolysates are used as media supplements to support the growth and productivity of CHO cultures for biopharmaceutical production. Through fractionation of a yeast lysate and metabolic analysis of a fraction that had bioactivity equivalent to commercial yeast extract (YE), bioactive components were identified that promoted growth and productivity of two recombinant CHO cell lines (CHO-Luc and CHO-hFcEG2) equivalent to or greater than YE-supplemented media. Autolysis of the yeast lysate was not necessary for full activity, suggesting that the active components are present in untreated yeast cells. A bioactive fraction (3KF) of the yeast lysate was isolated from the permeate using a 3kDa molecular weight cut-off (MWCO) filter. Supplementation of this 3KF fraction into the base media supported growth of CHO-Luc cells over eight passages equivalent to YE-supplemented media. The 3KF fraction was fractionated further by a cation exchange spin column using a stepwise pH elution. Metabolomic analysis of a bioactive fraction isolated at high pH identified several arginine and lysine-containing peptides as well as two polyamines, spermine and spermidine, with 3.5× and 4.5× higher levels compared to a fraction showing no bioactivity. The addition of a mixture of polyamines and their precursors (putrescine, spermine, spermidine, ornithine and citrulline) as well as increasing the concentration of some of the components of the original base medium resulted in a chemically-defined (CD) formulation that produced an equivalent viable cell density (VCD) and productivity of the CHO-Luc cells as the YE-supplemented medium. The VCD of the CHO-hFcEG2 culture in the CD medium was 1.9× greater and with equivalent productivity to the YE-supplemented media.

  20. Physicochemical analysis of initial adhesion and biofilm formation of Methanosarcina barkeri on polymer support material.

    PubMed

    Nguyen, Vi; Karunakaran, Esther; Collins, Gavin; Biggs, Catherine A

    2016-07-01

    The retention of selective biofilms of Methanosarcina species within anaerobic digesters could reduce start-up times and enhance the efficiency of the process in treating high-strength domestic sewage. The objective of the study was to examine the effect of the surface characteristics of six common polymer support materials on the initial adhesion of the model methanogen, Methanosarcina barkeri, and to assess the potential of these support materials as selective biofilm carriers. Results from both the initial adhesion tests and extended DLVO (xDLVO) model correlated with each other, with PVC (12% surface coverage/mm(2)), PTFE (6% surface coverage/mm(2)), and PP (6% surface coverage/mm(2)), shown to be the better performing support materials for initial adhesion, as well as subsequent biofilm formation by M. barkeri after 72h. Experimental results of these three support materials showed that the type of material strongly influenced the extent of adhesion from M. barkeri (p<0.0001), and the xDLVO model was able to explain the results in these environmental conditions. Therefore, DLVO physicochemical forces were found to be influential on the initial adhesion of M. barkeri. Scanning electron microscopy suggested that production of extracellular polymeric substances (EPS) from M. barkeri could facilitate further biofilm development. This study highlights the potential of using the xDLVO model to rapidly identify suitable materials for the selective adhesion of M. barkeri, which could be beneficial in both the start-up and long-term phases of anaerobic digestion.

  1. Carbon fiber as an excellent support material for wastewater treatment biofilms.

    PubMed

    Matsumoto, Shinya; Ohtaki, Akihito; Hori, Katsutoshi

    2012-09-18

    Fibrous materials made of carbon fiber (CF), aromatic polyamide (AP), preoxidized polyacrylonitrile (PAN), and polyethylene (PE), which are widely used in the textile industry, were evaluated as biofilm supports for wastewater treatment. We found that CF has a high capacity for adsorbing nitrifying bacterial sludge. The adhesion rate of four pure strains-Cytophaga hutchinsonii, Alcaligenes faecalis, Bacillus subtilis, and Escherichia coli-was highest to CF. The ζ-potentials of the fibrous supports, and the cell surface potentials of these bacteria on the basis of the soft particle theory, were experimentally determined. Bacterial cell adhesion to the fibrous supports could be explained by Derjaguin-Landau-Verwey-Overbeek theory. Interaction energy profiles based on this theory indicated the disappearance of the energy barrier in bacterial cell adhesion to the CF support, whereas an insurmountable energy barrier was observed in the adhesion to the other fibrous supports. This result was attributed to the less negative ζ-potential of CF and the relatively large Hamaker constant for the CF/bacterium interaction in water; through simulations, the latter factor was found to make a greater contribution to lowering the energy barrier. In practice and theory, CF is an excellent material as a microbial and biofilm support for wastewater treatment.

  2. Supporting Teachers' Use of a Project-Based Learning Environment in Ocean Science: Web-Based Educative Curriculum Materials

    ERIC Educational Resources Information Center

    Duncan, Ravit Golan; El-Moslimany, Hebbah; McDonnell, Janice; Lichtenwalner, Sage

    2011-01-01

    The development of inquiry and project-based materials is challenging in many ways, not the least of which is the design of supports for teachers implementing such materials. We report on the design of educative and just-in-time teacher supports for an online project-based unit in ocean science. The teacher supports were visible as tabs on the…

  3. Dependence of the Impact Response of Polyvinylidene Fluoride Sensors on Their Supporting Materials' Elasticity

    PubMed Central

    Jia, Yunfang; Chen, Xinjuan; Ni, Qingshan; Li, Longhua; Ju, Cheng

    2013-01-01

    Polyvinylidene fluoride (PVDF) is popular sensing material because of its unique piezoelectric characteristics. In this work an impact sensor was prepared from a sandwiched structure PVDF film, and the related detection circuits were presented. The dependence of the PVDF sensors' response on the elasticity of the supporting materials was examined and discussed. Here two response indexes were discussed, which were the peak-to-peak voltage (Vpp) and the recovery time. Firstly, falling impact experiments were executed on desk-supported PVDF sensors (100 μm PVDF film) using free falls of different weights from different heights. Then the same shock experiments were repeated on the same sensor, but changing the backstops to a sponge and rubber, respectively. On the desk, the values of Vpp were bigger than when the other two backstops were used; but the changes of the impact energy could not be reflected by the PVDF sensor when it was supported by a hard material. It was found that the biggest sensitivity of the voltage response (about 96.62 V/J) was obtained by the sponge-supported sensor; for the same sensor, when it was supported by rubber, the slope was 82.26 V/J. Moreover, the recovery time for the desk-supported sensor was almost constant, varying from 0.15 to 0.18 s, while for the same sensor supported by sponge or rubber, its recovery time changed with the shifting of the impact energy in the range of 0.02∼0.36 s, but no pattern could be found in the recovery-time characteristics. PMID:23881132

  4. Comparison of electron beam and laser beam powder bed fusion additive manufacturing process for high temperature turbine component materials

    SciTech Connect

    Dryepondt, Sebastien N; Pint, Bruce A; Ryan, Daniel

    2016-04-01

    The evolving 3D printer technology is now at the point where some turbine components could be additive manufactured (AM) for both development and production purposes. However, this will require a significant evaluation program to qualify the process and components to meet current design and quality standards. The goal of the project was to begin characterization of the microstructure and mechanical properties of Nickel Alloy X (Ni-22Cr-18Fe-9Mo) test bars fabricated by powder bed fusion (PBF) AM processes that use either an electron beam (EB) or laser beam (LB) power source. The AM materials produced with the EB and LB processes displayed significant differences in microstructure and resultant mechanical properties. Accordingly, during the design analysis of AM turbine components, the specific mechanical behavior of the material produced with the selected AM process should be considered. Comparison of the mechanical properties of both the EB and LB materials to those of conventionally processed Nickel Alloy X materials indicates the subject AM materials are viable alternatives for manufacture of some turbine components.

  5. Support vector machine to predict diesel engine performance and emission parameters fueled with nano-particles additive to diesel fuel

    NASA Astrophysics Data System (ADS)

    Ghanbari, M.; Najafi, G.; Ghobadian, B.; Mamat, R.; Noor, M. M.; Moosavian, A.

    2015-12-01

    This paper studies the use of adaptive Support Vector Machine (SVM) to predict the performance parameters and exhaust emissions of a diesel engine operating on nanodiesel blended fuels. In order to predict the engine parameters, the whole experimental data were randomly divided into training and testing data. For SVM modelling, different values for radial basis function (RBF) kernel width and penalty parameters (C) were considered and the optimum values were then found. The results demonstrate that SVM is capable of predicting the diesel engine performance and emissions. In the experimental step, Carbon nano tubes (CNT) (40, 80 and 120 ppm) and nano silver particles (40, 80 and 120 ppm) with nanostructure were prepared and added as additive to the diesel fuel. Six cylinders, four-stroke diesel engine was fuelled with these new blended fuels and operated at different engine speeds. Experimental test results indicated the fact that adding nano particles to diesel fuel, increased diesel engine power and torque output. For nano-diesel it was found that the brake specific fuel consumption (bsfc) was decreased compared to the net diesel fuel. The results proved that with increase of nano particles concentrations (from 40 ppm to 120 ppm) in diesel fuel, CO2 emission increased. CO emission in diesel fuel with nano-particles was lower significantly compared to pure diesel fuel. UHC emission with silver nano-diesel blended fuel decreased while with fuels that contains CNT nano particles increased. The trend of NOx emission was inverse compared to the UHC emission. With adding nano particles to the blended fuels, NOx increased compared to the net diesel fuel. The tests revealed that silver & CNT nano particles can be used as additive in diesel fuel to improve complete combustion of the fuel and reduce the exhaust emissions significantly.

  6. Modeling the mechanical and aging properties of silicone rubber and foam - stockpile-historical & additively manufactured materials

    SciTech Connect

    Maiti, A.; Weisgraber, T. H.; Gee, R. H.

    2014-09-30

    M97* and M9763 belong to the M97xx series of cellular silicone materials that have been deployed as stress cushions in some of the LLNL systems. Their purpose of these support foams is to distribute the stress between adjacent components, maintain relative positioning of various components, and mitigate the effects of component size variation due to manufacturing and temperature changes. In service these materials are subjected to a continuous compressive strain over long periods of time. In order to ensure their effectiveness, it is important to understand how their mechanical properties change over time. The properties we are primarily concerned about are: compression set, load retention, and stress-strain response (modulus).

  7. Impact of implant number, distribution and prosthesis material on loading on implants supporting fixed prostheses.

    PubMed

    Ogawa, T; Dhaliwal, S; Naert, I; Mine, A; Kronstrom, M; Sasaki, K; Duyck, Joke

    2010-07-01

    The purpose of this study is to evaluate axial forces and bending moments (BMs) on implants supporting a complete arch fixed implant supported prosthesis with respect to number and distribution of the implants and type of prosthesis material. Seven oral Brånemark implants with a diameter of 3.75 mm and a length of 13 and 7 mm (short distal implant) were placed in an edentulous composite mandible used as the experimental model. One all-acrylic, one fibre-reinforced acrylic, and one milled titanium framework prosthesis were made. A 50 N vertical load was applied on the extension 10 mm distal from the most posterior implant. Axial forces and BMs were measured by calculating signals from three strain gauges attached to each of the abutments. The load was measured using three different models with varying numbers of supporting implants (3, 4 and 5), three models with different implant distribution conditions (small, medium and large) and three models with different prosthesis materials (titanium, acrylic and fibre-reinforced acrylic). Maximum BMs were highest when prostheses were supported by three implants compared to four and five implants (P < 0.001). The BMs were significantly influenced by the implant distribution, in that the smallest distribution induced the highest BMs (P < 0.001). Maximum BMs were lowest with the titanium prosthesis (P < 0.01). The resultant forces on implants were significantly associated with the implant number and distribution and the prosthesis material.

  8. The selection and use of new materials in support of future ESA space science missions

    NASA Astrophysics Data System (ADS)

    Paulsen, T.

    2003-09-01

    The directorate of science of the European Space Agency has embarked on the definition and implementation of a series of new challenging scientific missions, in which the harsh space environment and demanding instrument performance requirements calls for the use of new materials. Among these missions the BepiColombo mission to Mercury calls for the use of high-temperature resistant materials, while the GAIA astrometry mission, where ultra-high thermo-mechanical stability of the optical bench is of critical importance, leads to the extensive use of Silicon Carbon (SiC) ceramics. A number of pre-developments contracts are currently running to support the development and the characterisation of these and other materials. This paper presents a summary of the activities related to these materials, considered critical to the safe and timely development of these missions.

  9. [Antibacterial effect of food additives and detergents against histamine-producing bacteria on food contact material surfaces].

    PubMed

    Kamii, Eri; Terada, Gaku; Akiyama, Junki; Isshiki, Kenji

    2011-01-01

    We investigated the antibacterial activity of food additives and detergents against histamine-producing bacteria on food contact material surfaces. Based on minimum inhibitory concentration (MIC) testing with Morganella morganii NBRC3848, Raoultella planticola NBRC3317 and Enterobacter aerogenes NCTC10006, we screened nine food additives and four detergents with relatively high inhibitory potency. We prepared food contact material surfaces contaminated with histamine-producing bacteria, and dipped them into fourteen agents (100 µg/mL). Sodium hypochlorite, benzalkonium chloride, benzethonium chloride, n-hexadecyltrimethylammonium chloride and 1-n-hexadecylpyridinium chloride showed antibacterial activity against histamine-producing bacteria. We prepared low concentrations of the five agents (10 and 50 µg/mL) and tested them in the same way. Sodium hypochlorite showed high antibacterial activity at 10 µg/mL, and the other four showed activity at 50 µg/mL. So, washing the material surface with these reagents might be effective to prevent histamine food poisoning owing to bacterial contamination of food contact surfaces.

  10. Surface characterization of an energetic material, pentaerythritoltetranitrate (PETN), having a thin coating achieved through a starved addition microencapsulation technique

    SciTech Connect

    Worley, C.M.

    1986-05-07

    The objective of this research was to: (1) determine the nature of a thin coating on an explosive material which was applied using a starved addition microencapsulation technique, (2) understand the coating/crystal bond, and (3) investigate the wettability/adhesion of plastic/solvent combinations using the coating process. The coating used in this work was a Firestone Plastic Company copolymer (FPC-461) of vinylchloride/trifluorochloroethylene in a 1.5/1.0 weight ratio. The energetic explosive examined was pentaerythritoltetranitrate (PETN). The coating process used was starved addition followed by a solvent evaporation technique. Surface analytical studies, completed for characterization of the coating process, show (1) evidence that the polymer coating is present, but not continuous, over the surface of PETN; (2) the average thickness of the polymer coating is between 16-32 A and greater than 44 A, respectively, for 0.5 and 20 wt % coated PETN; (3) no changes in surface chemistry of the polymer or the explosive material following microencapsulation; and (4) the presence of explosive material on the surface of 0.5 wt % FPC-461 coated explosives. 5 refs., 15 figs., 6 tabs.

  11. Influence of the supporting die structures on the fracture strength of all-ceramic materials.

    PubMed

    Yucel, Munir Tolga; Yondem, Isa; Aykent, Filiz; Eraslan, Oğuz

    2012-08-01

    This study investigated the influence of the elastic modulus of supporting dies on the fracture strengths of all-ceramic materials used in dental crowns. Four different types of supporting die materials (dentin, epoxy resin, brass, and stainless steel) (24 per group) were prepared using a milling machine to simulate a mandibular molar all-ceramic core preparation. A total number of 96 zirconia cores were fabricated using a CAD/CAM system. The specimens were divided into two groups. In the first group, cores were cemented to substructures using a dual-cure resin cement. In the second group, cores were not cemented to the supporting dies. The specimens were loaded using a universal testing machine at a crosshead speed of 0.5 mm/min until fracture occurred. Data were statistically analyzed using two-way analysis of variance and Tukey HSD tests (α = 0.05). The geometric models of cores and supporting die materials were developed using finite element method to obtain the stress distribution of the forces. Cemented groups showed statistically higher fracture strength values than non-cemented groups. While ceramic cores on stainless steel dies showed the highest fracture strength values, ceramic cores on dentin dies showed the lowest fracture strength values among the groups. The elastic modulus of the supporting die structure is a significant factor in determining the fracture resistance of all-ceramic crowns. Using supporting die structures that have a low elastic modulus may be suitable for fracture strength tests, in order to accurately reflect clinical conditions.

  12. A color-tunable luminescent material with functionalized graphitic carbon nitride as multifunctional supports

    NASA Astrophysics Data System (ADS)

    Lu, Jiutian; Cao, Yudong; Fan, Hai; Hou, Juying; Ai, Shiyun

    2015-12-01

    A color-tunable luminescent material was prepared based on the composition of functionalized graphitic carbon nitride (g-C3N4) and europium (III). The functionalized g-C3N4 layers not only behave as multifunctional supports including ligand coordinated with europium (III) and a support structure for the formation of the luminescent material, but exhibit excitation wavelength-dependent luminescence, thus the energy transfer between the functionalized g-C3N4 and europium (III) can match very well by controlling the emission wavelength of functionalized g-C3N4. The as-prepared materials was comprehensively characterized via X-ray photoelectron spectroscopy, Fourier Transform Infrared spectroscopy, X-ray scattering techniques, Ultraviolet and Visible spectrophotometer, fluorescence spectrophotometer, thermogravimetric analysis, etc. The luminescent material exhibits multi-color emissions which are consistent with the characteristic emissions of europium (III) and functionalized g-C3N4, and the photoluminescence quality and density of the europium (III) can be greatly enhanced. The brilliant optical properties of the materials make them suiting for multipurpose applications in practical fields.

  13. ESF GROUND SUPPORT - MATERIAL DEDICATION ANALYSIS FOR STRUCTURAL STEEL AND ACCESSORIES FROM A COMMERCIAL GRADE SOURCE

    SciTech Connect

    M.D. Stine

    1996-01-23

    The purpose of this analysis is to select the critical characteristics to be verified for steel sets and accessories and the verification methods to be implemented through a material dedication process for the procurement and use of commercial grade structural steel sets and accessories (which have a nuclear safety function) to be used in ground support (with the exception of alcove ground support and alcove opening framing, which are not addressed in this analysis) for the Exploratory Studies Facility (ESF) Topopah Spring (TS) Loop. The ESF TS Loop includes the North Ramp, Main Drift, and South Ramp underground openings.

  14. Additive-Free Transparent Triarylamine-Based Polymeric Hole-Transport Materials for Stable Perovskite Solar Cells.

    PubMed

    Matsui, Taisuke; Petrikyte, Ieva; Malinauskas, Tadas; Domanski, Konrad; Daskeviciene, Maryte; Steponaitis, Matas; Gratia, Paul; Tress, Wolfgang; Correa-Baena, Juan-Pablo; Abate, Antonio; Hagfeldt, Anders; Grätzel, Michael; Nazeeruddin, Mohammad Khaja; Getautis, Vytautas; Saliba, Michael

    2016-09-22

    Triarylamine-based polymers with different functional groups were synthetized as hole-transport materials (HTMs) for perovskite solar cells (PSCs). The novel materials enabled efficient PSCs without the use of chemical doping (or additives) to enhance charge transport. Devices employing poly(triarylamine) with methylphenylethenyl functional groups (V873) showed a power conversion efficiency of 12.3 %, whereas widely used additive-free poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) demonstrated 10.8 %. Notably, devices with V873 enabled stable PSCs under 1 sun illumination at maximum power point tracking for approximately 40 h at room temperature, and in the dark under elevated temperature (85 °C) for more than 140 h. This is in stark contrast to additive-containing devices, which degrade significantly within the same time frame. The results present remarkable progress towards stable PSC under real working conditions and industrial stress tests.

  15. Materials technology programs in support of a mercury Rankine space power system

    NASA Technical Reports Server (NTRS)

    Stone, P. L.

    1973-01-01

    A large portion of the materials technology is summarized that was generated in support of the development of a mercury-rankine space power system (SNAP-8). The primary areas of investigation are: (1) the compatibility of various construction materials with the liquid metals mercury and NaK, (2) the mechanical properties of unalloyed tantalum, and (3) the development of refractory metal/austenitic stainless steel tubing and transition joints. The primary results, conclusions, and state of technology at the completion of this effort for each of these areas are summarized. Results of possible significance to other applications are highlighted.

  16. High accuracy determination of the thermal properties of supported 2D materials.

    PubMed

    Judek, Jarosław; Gertych, Arkadiusz P; Świniarski, Michał; Łapińska, Anna; Dużyńska, Anna; Zdrojek, Mariusz

    2015-07-16

    We present a novel approach for the simultaneous determination of the thermal conductivity κ and the total interface conductance g of supported 2D materials by the enhanced opto-thermal method. We harness the property of the Gaussian laser beam that acts as a heat source, whose size can easily and precisely be controlled. The experimental data for multi-layer graphene and MoS2 flakes are supplemented using numerical simulations of the heat distribution in the Si/SiO2/2D material system. The procedure of κ and g extraction is tested in a statistical approach, demonstrating the high accuracy and repeatability of our method.

  17. High accuracy determination of the thermal properties of supported 2D materials

    NASA Astrophysics Data System (ADS)

    Judek, Jarosław; Gertych, Arkadiusz P.; Świniarski, Michał; Łapińska, Anna; Dużyńska, Anna; Zdrojek, Mariusz

    2015-07-01

    We present a novel approach for the simultaneous determination of the thermal conductivity κ and the total interface conductance g of supported 2D materials by the enhanced opto-thermal method. We harness the property of the Gaussian laser beam that acts as a heat source, whose size can easily and precisely be controlled. The experimental data for multi-layer graphene and MoS2 flakes are supplemented using numerical simulations of the heat distribution in the Si/SiO2/2D material system. The procedure of κ and g extraction is tested in a statistical approach, demonstrating the high accuracy and repeatability of our method.

  18. Associations between social support network characteristics and receipt of emotional and material support among a sample of male sexual minority youth.

    PubMed

    Kapadia, Farzana; Halkitis, Perry; Barton, Staci; Siconolfi, Daniel; Figueroa, Rafael Perez

    2014-01-01

    Few studies have examined how social support network characteristics are related to perceived receipt of social support among male sexual minority youth. Using egocentric network data collected from a study of male sexual minority youth (n=592), multivariable logistic regression analyses examined distinct associations between individual and social network characteristics with receipt of (1) emotional and (2) material support. In multivariable models, frequent communication and having friends in one's network yielded a two-fold increase in the likelihood of receiving emotional support whereas frequent communication was associated with an almost three-fold higher likelihood of perceived material support. Finally, greater internalized homophobia and personal experiences of gay-related stigma were inversely associated with perceived receipt of emotional and material support, respectively. Understanding the evolving social context and social interactions of this new generation of male sexual minority youth is warranted in order to understand the broader, contextual factors associated with their overall health and well-being.

  19. A color-tunable luminescent material with functionalized graphitic carbon nitride as multifunctional supports

    SciTech Connect

    Lu, Jiutian; Cao, Yudong; Fan, Hai; Hou, Juying; Ai, Shiyun

    2015-12-15

    A color-tunable luminescent material was prepared based on the composition of functionalized graphitic carbon nitride (g-C{sub 3}N{sub 4}) and europium (III). The functionalized g-C{sub 3}N{sub 4} layers not only behave as multifunctional supports including ligand coordinated with europium (III) and a support structure for the formation of the luminescent material, but exhibit excitation wavelength-dependent luminescence, thus the energy transfer between the functionalized g-C{sub 3}N{sub 4} and europium (III) can match very well by controlling the emission wavelength of functionalized g-C{sub 3}N{sub 4}. The as-prepared materials was comprehensively characterized via X-ray photoelectron spectroscopy, Fourier Transform Infrared spectroscopy, X-ray scattering techniques, Ultraviolet and Visible spectrophotometer, fluorescence spectrophotometer, thermogravimetric analysis, etc. The luminescent material exhibits multi-color emissions which are consistent with the characteristic emissions of europium (III) and functionalized g-C{sub 3}N{sub 4}, and the photoluminescence quality and density of the europium (III) can be greatly enhanced. The brilliant optical properties of the materials make them suiting for multipurpose applications in practical fields. - Graphical abstract: Schematic illustration of the synthesis and basic composition of the luminescent material. Inset figures were luminescence emission spectra of g-C{sub 3}N{sub 4} (A), europium (III) complex (a) and luminescent material (b) with the same concentration in (B) (K{sub ex}=350 nm) and photographs of (left) H{sub 2}O and (right) the H{sub 2}O dispersion of luminescence emission spectra under 350 nm UV radiation. The energy transfer in the luminescent material matchs very well and it exhibits multi-color emissions simultaneously. The enhanced photoluminescence quality and density of the europium (III) makes them suiting for multipurpose applications in practical fields. - Highlights: • Luminescent

  20. Materials used in new generation vehicles: supplies, shifts, and supporting infrastructure

    SciTech Connect

    Das, S.; Curlee, T.R.; Schexnayder, S.M.

    1997-08-01

    The Partnership for a New Generation of Vehicles (PNGV) program intends to develop new designs for automobiles that will reduce fuel consumption by two thirds but otherwise have price, comfort, safety, and other measures of performance similar to the typical automobile now on the market. PNGV vehicle designs are expected to substitute lightweight materials, such as aluminum, magnesium, carbon-reinforced polymer composites, glass-reinforced polymer composites, and ultra- light steel, for heavier materials such as steel and iron in automobile components. The target mass of a PNGV vehicle is 1,960 pounds, as compared to the average current vehicle that weights 3,240 pounds. Other changes could include the use of different ferrous alloys, engineering changes, or incorporation of advanced ceramic components. Widespread adoption of these vehicle designs would affect materials markets and require concurrent development and adoption of supporting technologies to supply the materials and to use and maintain them in automobiles. This report identifies what would be required to bring about these changes and developments in materials substitution; identifies reasons that might make these substitutions difficult to accomplish within the overall objectives and timetable of the PNGV program; and identifies any issues arising from the substitution that could prompt consideration of policies to deal with them. The analysis in this paper uses scenarios that assume the production of new generation vehicles will begin in 2007 and that their market share will increase gradually over the following 25 years. The scenarios on which the analysis is based assume a maximum substitution of each potential replacement material considered. This maximum substitution of individual materials (i.e., the amount of replacement material by weight that would be added to the baseline vehicle`s composition) is as follows: ULSAB (high strength steel), 298 lbs.; glass-reinforced composites, 653 lbs.; carbon

  1. A pathway-based analysis provides additional support for an immune-related genetic susceptibility to Parkinson's disease.

    PubMed

    Holmans, Peter; Moskvina, Valentina; Jones, Lesley; Sharma, Manu; Vedernikov, Alexey; Buchel, Finja; Saad, Mohamad; Sadd, Mohamad; Bras, Jose M; Bettella, Francesco; Nicolaou, Nayia; Simón-Sánchez, Javier; Mittag, Florian; Gibbs, J Raphael; Schulte, Claudia; Durr, Alexandra; Guerreiro, Rita; Hernandez, Dena; Brice, Alexis; Stefánsson, Hreinn; Majamaa, Kari; Gasser, Thomas; Heutink, Peter; Wood, Nicholas W; Martinez, Maria; Singleton, Andrew B; Nalls, Michael A; Hardy, John; Morris, Huw R; Williams, Nigel M

    2013-03-01

    Parkinson's disease (PD) is the second most common neurodegenerative disease affecting 1-2% in people >60 and 3-4% in people >80. Genome-wide association (GWA) studies have now implicated significant evidence for association in at least 18 genomic regions. We have studied a large PD-meta analysis and identified a significant excess of SNPs (P < 1 × 10(-16)) that are associated with PD but fall short of the genome-wide significance threshold. This result was independent of variants at the 18 previously implicated regions and implies the presence of additional polygenic risk alleles. To understand how these loci increase risk of PD, we applied a pathway-based analysis, testing for biological functions that were significantly enriched for genes containing variants associated with PD. Analysing two independent GWA studies, we identified that both had a significant excess in the number of functional categories enriched for PD-associated genes (minimum P = 0.014 and P = 0.006, respectively). Moreover, 58 categories were significantly enriched for associated genes in both GWA studies (P < 0.001), implicating genes involved in the 'regulation of leucocyte/lymphocyte activity' and also 'cytokine-mediated signalling' as conferring an increased susceptibility to PD. These results were unaltered by the exclusion of all 178 genes that were present at the 18 genomic regions previously reported to be strongly associated with PD (including the HLA locus). Our findings, therefore, provide independent support to the strong association signal at the HLA locus and imply that the immune-related genetic susceptibility to PD is likely to be more widespread in the genome than previously appreciated.

  2. 18 CFR 346.2 - Material in support of initial rates or change in rates.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... initial rates or change in rates. 346.2 Section 346.2 Conservation of Power and Water Resources FEDERAL... PIPELINE COST-OF-SERVICE FILING REQUIREMENTS § 346.2 Material in support of initial rates or change in rates. A carrier that files for rates pursuant to § 342.2(a) or § 342.4(a) of this chapter, or a...

  3. Effect of carbohydrate substrate on fermentation by kefir yeast supported on delignified cellulosic materials.

    PubMed

    Athanasiadis, I; Boskou, D; Kanellaki, M; Koutinas, A A

    2001-02-01

    The suitability of delignified cellulosic (DC) material supported kefir yeast to ferment raw materials that contain various single carbohydrates, for the production of potable alcohol and alcoholic drinks, is examined in this investigation. Results are reported of fermentations carried out with sucrose, fructose, and glucose in synthetic media. Repeated batch fermentations at various initial sugar concentrations of sucrose, fructose, and glucose were performed at 30 degrees C in the presence of the aforementioned biocatalyst. The results clearly show feasible yields in the range of 0.38-0.41 g/g, alcohol concentrations of 7.6-8.2% v/v, fermentation time of 90-115 h, and conversion of 92-96%. DC material supported kefir fermented 11-fold more rapidly than free cells and 9-fold more rapidly in comparison to kissiris supported kefir. The main volatile byproducts such as amyl alcohols (mixture of 2-methyl-1-butanol and 3-methyl-1-butanol), ethanal, and ethyl acetate were formed in all sugar fermentation products. The formation of 65-110 ppm of ethyl acetate is as high and even higher than that obtained with traditional wine yeasts. The increase of the initial concentration of sugar in the fermentation media resulted in an increase in contents of volatiles. The fine aroma that was obtained in the product of fructose could be attributed to the high percentage of ethyl acetate on total volatiles. The efficiency of DC material supported kefir was the same for the fermentations of individual sugars or a mixture of fructose, sucrose, and glucose. When whey with raisin extracts was fermented, lower yields were obtained but the aroma of the product was even better.

  4. Energetic materials research and development activities at Sandia National Laboratories supported under DP-10 programs

    SciTech Connect

    Ratzel, A.C. III

    1998-09-01

    This report provides summary descriptions of Energetic Materials (EM) Research and Development activities performed at Sandia National Laboratories and funded through the Department of Energy DP-10 Program Office in FY97 and FY98. The work falls under three major focus areas: EM Chemistry, EM Characterization, and EM Phenomenological Model Development. The research supports the Sandia component mission and also Sandia's overall role as safety steward for the DOE Nuclear Weapons Complex.

  5. Immobilization of heavy metals in polluted soils by the addition of zeolitic material synthesized from coal fly ash.

    PubMed

    Querol, Xavier; Alastuey, Andrés; Moreno, Natàlia; Alvarez-Ayuso, Esther; García-Sánchez, Antonio; Cama, Jordi; Ayora, Carles; Simón, Mariano

    2006-01-01

    The use of zeolitic material synthesized from coal fly ash for the immobilization of pollutants in contaminated soils was investigated in experimental plots in the Guadiamar Valley (SW Spain). This area was affected by a pyrite slurry spill in April 1998. Although reclamation activities were completed in a few months, residual pyrite slurry mixed with soil accounted for relatively high leachable levels of trace elements such as Zn, Pb, As, Cu, Sb, Co, Tl and Cd. Phytoremediation strategies were adopted for the final recovery of the polluted soils. The immobilization of metals had previously been undertaken to avoid leaching processes and the consequent groundwater pollution. To this end, 1100 kg of high NaP1 (Na6[(AlO2)6(SiO2)10] .15H2O) zeolitic material was synthesized using fly ash from the Teruel power plant (NE Spain), in a 10 m3 reactor. This zeolitic material was manually applied using different doses (10000-25000 kg per hectare), into the 25 cm topsoil. Another plot (control) was maintained without zeolite. Sampling was carried out 1 and 2 years after the zeolite addition. The results show that the zeolitic material considerably decreases the leaching of Cd, Co, Cu, Ni, and Zn. The sorption of metals in soil clay minerals (illite) proved to be the main cause contributing to the immobilization of these pollutants. This sorption could be a consequence of the rise in pH from 3.3 to 7.6 owing to the alkalinity of the zeolitic material added (caused by traces of free lime in the fly ash, or residual NaOH from synthesis).

  6. Effect of kaolin addition on the performance of controlled low-strength material using industrial waste incineration bottom ash.

    PubMed

    Naganathan, Sivakumar; Razak, Hashim Abdul; Hamid, Siti Nadzriah Abdul

    2010-09-01

    Incineration of industrial waste produces large quantities of bottom ash which are normally sent to secured landfill, but is not a sustainable solution. Use of bottom ash in engineering applications will contribute to sustainability and generate revenue. One way of using the industrial waste incineration bottom ash is in controlled low-strength material (CLSM). Use of bottom ash in CLSM has problems related to bleeding and excessive strength development and so an additive has to be used to control bleeding and strength development. The main objective of this research is to study the effect of kaolin addition on the performance of CLSM made using industrial waste incineration bottom ash. CLSM mixes were made with bottom ash, cement, and refined kaolin. Various tests were performed on the CLSM in fresh and hardened states including compressive strength, water absorption, California bearing ratio (CBR) and the tests for concentration of leachable substances on the bleed and leachate. The compressive strength of CLSM tested ranged from 0.11 to 9.86 MPa. CBR values ranged from 6 to 46, and water absorption values from 12 to 36%. It was shown that the addition of kaolin delayed the initial setting time of CLSM mixtures, reduced bleeding, lowered the compressive strength, and increased the values of water absorption, sorption, and initial surface absorption. The CLSM tested did not have corrosivity. It was shown that the hardened CLSM was non hazardous, and the addition of kaolin increased the concentration of heavy metals and salts in the bleed and leachate.

  7. Apparatus for supporting contactors used in extracting nuclear materials from liquids

    DOEpatents

    Leonard, Ralph A.; Frank, Robert C.

    1991-01-01

    Apparatus is provided for supporting one or more contactor stages used to remove radioactive materials from aqueous solutions. The contactor stages include a housing having an internal rotor, a motor secured to the top of the housing for rotating the rotor, and a drain in the bottom of the housing. The support apparatus includes two or more vertical members each secured to a ground support that is horizontal and perpendicular to the frame member, and a horizontally disposed frame member. The frame member may be any suitable shape, but is preferably a rectangular tube having substantially flat, spaced top and bottom surfaces separated by substantially vertical side surfaces. The top and bottom surfaces each have an opening through which the contactor housing is secured so that the motor is above the frame and the drain is below the frame during use.

  8. Sorptive uptake of selenium with magnetite and its supported materials onto activated carbon.

    PubMed

    Kwon, Jae H; Wilson, Lee D; Sammynaiken, R

    2015-11-01

    Kinetic and equilibrium uptake studies of selenite in aqueous solution with synthetic magnetite (Mag-P), commercial magnetite (Mag-C), goethite, activated carbon (AC), and a composite material containing 19% magnetite supported on activated carbon (CM-19) were investigated. Kinetic uptake studies used a one-pot setup at pH 5.26 at variable temperature. Sampling of unbound selenite in-situ was achieved with analytical detection by atomic absorbance. The sorptive uptake at equilibrium and kinetic conditions are listed in descending order: goethite>Mag-P>Mag-C>CM-19. Kinetic uptake parameters reveal that Mag-P showed apparent negative values for the activation energy (E(a)) and the enthalpy of activation (ΔH(‡)), in agreement with a multi-step process for the kinetic uptake of selenite. By contrast, Mag-C, CM-19, and goethite showed positive values for E(a) and ΔH(‡). The uptake properties of the various sorbent materials with selenite are in accordance with the formation of inner- and out-sphere complexes. Leaching of iron from the composite material (CM-19) was attenuated due to the stabilizing effect of the magnetite within the pore sites and the surface of AC. Supported iron oxide nanomaterial composites represent a unique sorbent material with tunable uptake properties toward inorganic selenite in aqueous solution.

  9. Geochemistry and materials studies in support of the Magma Energy Extraction Program

    SciTech Connect

    Westrich, H.R.; Weirick, L.J.

    1986-01-01

    Geochemistry and materials studies are being performed in support of the Magma Energy Extraction Program. The scope of the studies is dictated by the sites under consideration and the designs of the drilling and energy extraction systems. The work has been largely restricted to characterizing magmatic environments at sites of interest and testing engineering materials in laboratory simulated rhyolite magmatic environments. The behavior of 17 commercially available materials has been examined at magmatic conditions. Analysis of reaction products reveal that oxidation, and not sulfidation, is the main corrosion problem for most alloys in rhyolite, and that reaction with other magmatic components is limited. Considerations of corrosion resistance, high-temperature strength, and cost indicate nickel-base superalloys offer the most promise as candidates for use in rhyolitic magma.

  10. Additive-Driven Assembly of Block Copolymer-Nanoparticle Hybrid Materials for Solution Processable Floating Gate Memory

    NASA Astrophysics Data System (ADS)

    Wei, Qingshuo; Lin, Ying; Anderson, Eric; Briseno, Alejandro; Gido, Samuel; Watkins, James

    2012-02-01

    The preparation of well-ordered hybrid materials at nanoscale is not only fundamentally interesting but also of significant importance for the development of next generation functional devices. In this study, we present a simple approach for the preparation of well-ordered polymer/NP composites through the concept of additive-driven assembly, and its application for the fabrication of floating gate organic FET memory devices. The addition of gold NPs that selectively hydrogen bond with pyridine in poly(styrene-b-2-vinyl pyridine) is shown to induce an ordered structure. This enables the fabrication of well-ordered hybrid materials with lamellar domains at Au NP loadings of more than 40 wt%. The fabrication of floating gate memory devices was demonstrated by the ordered Au NPs / block copolymer hybrid film as a charge trapping layer, which is sandwiched between a SiO2 dielectric layer and a poly(3-hexylthiophene) semiconductor layer. This approach enables us to fabricate well-ordered charge storage layers by solution processing and to achieve facile control of the memory windows by changing the density of gold NPs. The devices show high carrier mobility (> 0.1 cm^2/Vs), controllable memory windows (0˜50V), high on/off ratio (>10^5) between memory states and long retention times (>10^4 s). This approach is potentially suitable for roll-to-roll printing techniques to make flexible, large area and high density devices.

  11. Estimating the Additional Greenhouse Gas Emissions in Korea: Focused on Demolition of Asbestos Containing Materials in Building.

    PubMed

    Kim, Young-Chan; Hong, Won-Hwa; Zhang, Yuan-Long; Son, Byeung-Hun; Seo, Youn-Kyu; Choi, Jun-Ho

    2016-09-12

    When asbestos containing materials (ACM) must be removed from the building before demolition, additional greenhouse gas (GHG) emissions are generated. However, precedent studies have not considered the removal of ACM from the building. The present study aimed to develop a model for estimating GHG emissions created by the ACM removal processes, specifically the removal of asbestos cement slates (ACS). The second objective was to use the new model to predict the total GHG emission produced by ACM removal in the entire country of Korea. First, an input-equipment inventory was established for each step of the ACS removal process. Second, an energy consumption database for each equipment type was established. Third, the total GHG emission contributed by each step of the process was calculated. The GHG emissions generated from the 1,142,688 ACS-containing buildings in Korea was estimated to total 23,778 tonCO₂eq to 132,141 tonCO₂eq. This study was meaningful in that the emissions generated by ACS removal have not been studied before. Furthermore, the study deals with additional problems that can be triggered by the presence of asbestos in building materials. The method provided in this study is expected to contribute greatly to the calculation of GHG emissions caused by ACM worldwide.

  12. Estimating the Additional Greenhouse Gas Emissions in Korea: Focused on Demolition of Asbestos Containing Materials in Building

    PubMed Central

    Kim, Young-Chan; Hong, Won-Hwa; Zhang, Yuan-Long; Son, Byeung-Hun; Seo, Youn-Kyu; Choi, Jun-Ho

    2016-01-01

    When asbestos containing materials (ACM) must be removed from the building before demolition, additional greenhouse gas (GHG) emissions are generated. However, precedent studies have not considered the removal of ACM from the building. The present study aimed to develop a model for estimating GHG emissions created by the ACM removal processes, specifically the removal of asbestos cement slates (ACS). The second objective was to use the new model to predict the total GHG emission produced by ACM removal in the entire country of Korea. First, an input-equipment inventory was established for each step of the ACS removal process. Second, an energy consumption database for each equipment type was established. Third, the total GHG emission contributed by each step of the process was calculated. The GHG emissions generated from the 1,142,688 ACS-containing buildings in Korea was estimated to total 23,778 tonCO2eq to 132,141 tonCO2eq. This study was meaningful in that the emissions generated by ACS removal have not been studied before. Furthermore, the study deals with additional problems that can be triggered by the presence of asbestos in building materials. The method provided in this study is expected to contribute greatly to the calculation of GHG emissions caused by ACM worldwide. PMID:27626433

  13. Beyond Mentoring: A Review of Literature Detailing the Need for Additional and Alternative Forms of Support for Novice Music Teachers

    ERIC Educational Resources Information Center

    Bell-Robertson, Catherine G.

    2015-01-01

    Support for music teachers new to the profession is important and necessary. Some school districts use traditional mentor-mentee pairings as their primary support for novice music teachers; however, many factors in the professional lives of music teachers, such as traveling among multiple schools or a lack of subject-specific colleagues often…

  14. LEVERAGING AGING MATERIALS DATA TO SUPPORT EXTENSION OF TRANSPORTATION SHIPPING PACKAGES SERVICE LIFE

    SciTech Connect

    Dunn, K.; Bellamy, S.; Daugherty, W.; Sindelar, R.; Skidmore, E.

    2013-08-18

    Nuclear material inventories are increasingly being transferred to interim storage locations where they may reside for extended periods of time. Use of a shipping package to store nuclear materials after the transfer has become more common for a variety of reasons. Shipping packages are robust and have a qualified pedigree for performance in normal operation and accident conditions but are only certified over an approved transportation window. The continued use of shipping packages to contain nuclear material during interim storage will result in reduced overall costs and reduced exposure to workers. However, the shipping package materials of construction must maintain integrity as specified by the safety basis of the storage facility throughout the storage period, which is typically well beyond the certified transportation window. In many ways, the certification processes required for interim storage of nuclear materials in shipping packages is similar to life extension programs required for dry cask storage systems for commercial nuclear fuels. The storage of spent nuclear fuel in dry cask storage systems is federally-regulated, and over 1500 individual dry casks have been in successful service up to 20 years in the US. The uncertainty in final disposition will likely require extended storage of this fuel well beyond initial license periods and perhaps multiple re-licenses may be needed. Thus, both the shipping packages and the dry cask storage systems require materials integrity assessments and assurance of continued satisfactory materials performance over times not considered in the original evaluation processes. Test programs for the shipping packages have been established to obtain aging data on materials of construction to demonstrate continued system integrity. The collective data may be coupled with similar data for the dry cask storage systems and used to support extending the service life of shipping packages in both transportation and storage.

  15. The use of nanometer tetrabasic lead sulfate as positive active material additive for valve regulated lead-acid battery

    NASA Astrophysics Data System (ADS)

    Lang, Xiaoshi; Wang, Dianlong; Hu, Chiyu; Tang, Shenzhi; Zhu, Junsheng; Guo, Chenfeng

    2014-12-01

    Conventional tetrabasic lead sulfate used as positive active material additive shows the results of the low effective lead dioxide conversion rate due to the large grain size and crossed the crystal structure. In this paper, we study on a type of nanometer tetrabasic lead sulfate. Through the XRD and SEM test and Material Studio software calculation, the purity of tetrabasic lead sulfate is very high, the grain size of the nanometer 4BS is almost unanimous, and can be controlled below 200 nm. When charged and discharged in 1.75 V-2.42 V with the current density of 40 mA g-1, 80 mA g-1 and 160 mA g-1, the effective lead dioxide conversion rate of nanometer 4BS after formation can achieve to 83.48%, 71.42%, and 66.96%. Subsequently, the nanometer 4BS as additive is added to positive paste of lead-acid battery. When the batteries are tested galvanostatically between 1.75 V and 2.42 V at 0.25 C charge and 0.5 C discharge rates at room temperature. The ratio of adding nanometer 4BS is 0%, 1% and 4% and the initial discharge specific capacities are 60 mAh g-1, 65 mAh g-1 and 68 mAh g-1. After 80 cycles, the initial discharge capacity of positive active material with 1% nanometer 4BS decreased less than 10%, while adding 4% nanometer 4BS, the initial discharge capacity doesn't decrease obviously.

  16. Nano-structured support materials, their characterisation and serum protein profiling through MALDI/TOF-MS.

    PubMed

    Najam-Ul-Haq, M; Rainer, M; Heigl, N; Szabo, Z; Vallant, R; Huck, C W; Engelhardt, H; Bischoff, K-D; Bonn, G K

    2008-02-01

    In the bioanalytical era, novel nano-materials for the selective extraction, pre-concentration and purification of biomolecules prior to analysis are vital. Their application as affinity binding in this regard is needed to be authentic. We report here the comparative application of derivatised materials and surfaces on the basis of nano-crystalline diamond, carbon nanotubes and fullerenes for the analysis of marker peptides and proteins by material enhanced laser desorption ionisation mass spectrometry MELDI-MS. In this particular work, the emphasis is placed on the derivatization, termed as immobilised metal affinity chromatography (IMAC), with three different support materials, to show the effectiveness of MELDI technique. For the physicochemical characterisation of the phases, near infrared reflectance spectroscopy (NIRS) is used, which is a well-established method within the analytical chemistry, covering a wide range of applications. NIRS enables differentiation between silica materials and different fullerenes derivatives, in a 3-dimensional factor-plot, depending on their derivatizations and physical characteristics. The method offers a physicochemical quantitative description in the nano-scale level of particle size, specific surface area, pore diameter, pore porosity, pore volume and total porosity with high linearity and improved precision. The measurement takes only a few seconds while high sample throughput is guaranteed.

  17. Evaluating the Effectiveness of Physlet-Based Materials in Supporting Conceptual Learning About Electricity

    NASA Astrophysics Data System (ADS)

    Ülen, Simon; Gerlič, Ivan; Slavinec, Mitja; Repnik, Robert

    2017-04-01

    To provide a good understanding of many abstract concepts in the field of electricity above that of their students is often a major challenge for secondary school teachers. Many educational researchers promote conceptual learning as a teaching approach that can help teachers to achieve this goal. In this paper, we present Physlet-based materials for supporting conceptual learning about electricity. To conduct research into the effectiveness of these materials, we designed two different physics courses: one group of students, the experimental group, was taught using Physlet-based materials and the second group of students, the control group, was taught using expository instruction without using Physlets. After completion of the teaching, we assessed students' thinking skills and analysed the materials with an independent t test, multiple regression analyses and one-way analysis of covariance. The test scores were significantly higher in the experimental group than in the control group ( p < 0.05). The results of this study confirmed the effectiveness of conceptual learning about electricity with the help of Physlet-based materials.

  18. Evaluating the Effectiveness of Physlet-Based Materials in Supporting Conceptual Learning About Electricity

    NASA Astrophysics Data System (ADS)

    Ülen, Simon; Gerlič, Ivan; Slavinec, Mitja; Repnik, Robert

    2016-11-01

    To provide a good understanding of many abstract concepts in the field of electricity above that of their students is often a major challenge for secondary school teachers. Many educational researchers promote conceptual learning as a teaching approach that can help teachers to achieve this goal. In this paper, we present Physlet-based materials for supporting conceptual learning about electricity. To conduct research into the effectiveness of these materials, we designed two different physics courses: one group of students, the experimental group, was taught using Physlet-based materials and the second group of students, the control group, was taught using expository instruction without using Physlets. After completion of the teaching, we assessed students' thinking skills and analysed the materials with an independent t test, multiple regression analyses and one-way analysis of covariance. The test scores were significantly higher in the experimental group than in the control group (p < 0.05). The results of this study confirmed the effectiveness of conceptual learning about electricity with the help of Physlet-based materials.

  19. Effect of lime addition during sewage sludge treatment on characteristics of resulting SSA when it is used in cementitious materials.

    PubMed

    Vouk, D; Nakic, D; Štirmer, N; Baricevic, A

    2017-02-01

    Final disposal of sewage sludge is important not only in terms of satisfying the regulations, but the aspect of choosing the optimal wastewater treatment technology, including the sludge treatment. In most EU countries, significant amounts of stabilized and dewatered sludge are incinerated, and sewage sludge ash (SSA) is generated as a by product. At the same time, lime is one of the commonly used additives in the sewage sludge treatment primarily to stabilize the sludge. In doing so, the question arose how desirable is such addition of lime if the sludge is subsequently incinerated, and the generated ash is further used in the production of cementitious materials. A series of mortars were prepared where 10-20% of the cement fraction was replaced by SSA. Since all three types of analyzed SSA (without lime, with lime added during sludge stabilization and with extra lime added during sludge incineration) yielded nearly same results, it can be concluded that if sludge incineration is accepted solution, lime addition during sludge treatment is unnecessary even from the standpoint of preserving the pozzolanic properties of the resulting SSA. Results of the research carried out on cement mortars point to the great possibilities of using SSA in concrete industry.

  20. Rational molecular dynamics scheme for predicting optimum concentration loading of nano-additive in phase change materials

    NASA Astrophysics Data System (ADS)

    Rastogi, Monisha; Vaish, Rahul; Madhar, Niyaz Ahamad; Shaikh, Hamid; Al-Zahrani, S. M.

    2015-10-01

    The present study deals with the diffusion and phase transition behaviour of paraffin reinforced with carbon nano-additives namely graphene oxide (GO) and surface functionalized single walled carbon nanotubes (SWCNT). Bulk disordered systems of paraffin hydrocarbons impregnated with carbon nano-additives have been generated in realistic equilibrium conformations for potential application as latent heat storage systems. Ab initio molecular dynamics(MD) in conjugation with COMPASS forcefield has been implemented using periodic boundary conditions. The proposed scheme allows determination of optimum nano-additive loading for improving thermo-physical properties through analysis of mass, thermal and transport properties; and assists in determination of composite behaviour and related performance from microscopic point of view. It was observed that nanocomposites containing 7.8 % surface functionalised SWCNT and 55% GO loading corresponds to best latent heat storage system. The propounded methodology could serve as a by-pass route for economically taxing and iterative experimental procedures required to attain the optimum composition for best performance. The results also hint at the large unexplored potential of ab-initio classical MD techniques for predicting performance of new nanocomposites for potential phase change material applications.

  1. Investigating Teacher Learning Supports in High School Biology Curricular Programs to Inform the Design of Educative Curriculum Materials

    ERIC Educational Resources Information Center

    Beyer, Carrie J.; Delgado, Cesar; Davis, Elizabeth A.; Krajcik, Joseph

    2009-01-01

    Reform efforts have emphasized the need to support teachers' learning about reform-oriented practices. Educative curriculum materials are one potential vehicle for promoting teacher learning about these practices. Educative curriculum materials include supports that are intended to promote both student "and" teacher learning. However, little is…

  2. Nanostructured TiOx as a catalyst support material for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Phillips, Richard S.

    Recent interest in the development of new catalyst support materials for proton exchange membrane fuel cells (PEMFCs) has stimulated research into the viability of TiO2-based support structures. Specifically, substoichiometric TiO2 (TiOx) has been reported to exhibit a combination of high conductivity, stability, and corrosion resistance. These properties make TiOx-based support materials a promising prospect when considering the inferior corrosion resistance of traditional carbon-based supports. This document presents an investigation into the formation of conductive and stable TiOx thin films employing atomic layer deposition (ALD) and a post deposition oxygen reducing anneal (PDORA). Techniques for manufacturing TiOx-based catalyst support nanostructures by means of ALD in conjunction with carbon black (CB), anodic aluminum oxide (AAO) and silicon nanowires (SiNWs) will also be presented. The composition and thickness of resulting TiOx thin films was determined with the aid of Auger electron spectroscopy (AES), Rutherford backscattering spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM). Film crystal structure was determined with X-ray diffraction (XRD) analysis. Film conductivity was calculated using four-point probe (4-PP) and film thickness measurement data. Resulting thin films show a significant decrease of oxygen in ALD TiOx films corresponding with a great increase in conductivity following the PDORA. The effectiveness of the PDORA was also found to be highly dependent on ALD process parameters. TiOx-based nanostructures were coated with platinum using one of three Pt deposition techniques. First, liquid phase deposition (LPD), which was performed at room temperature, provided equal access to catalyst support material surfaces which were suspended in solution. Second, plasma enhanced atomic layer deposition (PEALD), which was performed at 450°C, provided good Pt

  3. Evaluation of support materials for the surface immobilization and decoloration of amaranth by Trametes versicolor.

    PubMed

    Shin, M; Nguyen, T; Ramsay, J

    2002-10-01

    The ability of Trametes versicolor ATCC 20869 to colonize several natural and synthetic materials (wheat straw, jute, hemp, maple woodchips, and nylon and polyethylene teraphthalate fibers) and to subsequently decolorize amaranth was evaluated. Jute was found to be the best support material as T. versicolor grew well on it without color leaching from the support and without loss of the jute's integrity over a 4 week period. The fungus immobilized on jute, straw and hemp decolorized amaranth (50 mg l(-1)) at a rate of about 5 mg l(-1) h(-1) without glucose being added. When 1 g l(-1) glucose was added, the dye was degraded more quickly (about 8 mg l(-1) h(-1)). Decoloration did not occur in a suspension culture without glucose. As the number of decoloration cycles increased, the rate of decoloration decreased. This rate was restored to its original level after the biomass was incubated in fresh growth medium for 5 days. With all immobilization supports, the toxicity of the medium before and after decoloration was the same or lower.

  4. Inorganic materials as supports for covalent enzyme immobilization: methods and mechanisms.

    PubMed

    Zucca, Paolo; Sanjust, Enrico

    2014-09-09

    Several inorganic materials are potentially suitable for enzymatic covalent immobilization, by means of several different techniques. Such materials must meet stringent criteria to be suitable as solid matrices: complete insolubility in water, reasonable mechanical strength and chemical resistance under the operational conditions, the capability to form manageable particles with high surface area, reactivity towards derivatizing/functionalizing agents. Non-specific protein adsorption should be always considered when planning covalent immobilization on inorganic solids. A huge mass of experimental work has shown that silica, silicates, borosilicates and aluminosilicates, alumina, titania, and other oxides, are the materials of choice when attempting enzyme immobilizations on inorganic supports. More recently, some forms of elemental carbon, silicon, and certain metals have been also proposed for certain applications. With regard to the derivatization/functionalization techniques, the use of organosilanes through silanization is undoubtedly the most studied and the most applied, although inorganic bridge formation and acylation with selected acyl halides have been deeply studied. In the present article, the most common inorganic supports for covalent immobilization of the enzymes are reviewed, with particular focus on their advantages and disadvantages in terms of enzyme loadings, operational stability, undesired adsorption, and costs. Mechanisms and methods for covalent immobilization are also discussed, focusing on the most widespread activating approaches (such as glutaraldehyde, cyanogen bromide, divinylsulfone, carbodiimides, carbonyldiimidazole, sulfonyl chlorides, chlorocarbonates, N-hydroxysuccinimides).

  5. On The Development of Additive Construction Technologies for Application to Development of Lunar/Martian Surface Structures Using In-Situ Materials

    NASA Technical Reports Server (NTRS)

    Werkheiser, Niki; Fiske, Michael; Edmunson, Jennifer; Khoshnevis, Behrokh

    2015-01-01

    For long-duration missions on other planetary bodies, the use of in-situ materials will become increasingly critical. As man's presence on these bodies expands, so must the breadth of the structures required to accommodate them including habitats, laboratories, berms, radiation shielding for natural radiation and surface reactors, garages, solar storm shelters, greenhouses, etc. Planetary surface structure manufacturing and assembly technologies that incorporate in-situ resources provide options for autonomous, affordable, pre-positioned environments with radiation shielding features and protection from micrometeorites, exhaust plume debris, and other hazards. This is important because gamma and particle radiation constitute a serious but reducible threat to long-term survival of human beings, electronics, and other materials in space environments. Also, it is anticipated that surface structures will constitute the primary mass element of lunar or Martian launch requirements. The ability to use in-situ materials to construct these structures will provide a benefit in the reduction of up-mass that would otherwise make long-term Moon or Mars structures cost prohibitive. The ability to fabricate structures in situ brings with it the ability to repair these structures, which allows for self-sufficiency necessary for long-duration habitation. Previously, under the auspices of the MSFC In Situ Fabrication and Repair (ISFR) project and more recently, under the joint MSFC/KSC Additive Construction with Mobile Emplacement (ACME) project, the MSFC Surface Structures Group has been developing materials and construction technologies to support future planetary habitats with in situ resources. One such technology, known as Contour Crafting (additive construction), is shown in Figure 1, along with a typical structure fabricated using this technology. This paper will present the results to date of these efforts, including development of novel nozzle concepts for advanced layer

  6. 49 CFR 40.303 - What happens if the SAP believes the employee needs additional treatment, aftercare, or support...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false What happens if the SAP believes the employee... the Return-to-Duty Process § 40.303 What happens if the SAP believes the employee needs additional...? (a) As a SAP, if you believe that ongoing services (in addition to follow-up tests) are needed...

  7. 49 CFR 40.303 - What happens if the SAP believes the employee needs additional treatment, aftercare, or support...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false What happens if the SAP believes the employee... the Return-to-Duty Process § 40.303 What happens if the SAP believes the employee needs additional...? (a) As a SAP, if you believe that ongoing services (in addition to follow-up tests) are needed...

  8. 49 CFR 40.303 - What happens if the SAP believes the employee needs additional treatment, aftercare, or support...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false What happens if the SAP believes the employee... the Return-to-Duty Process § 40.303 What happens if the SAP believes the employee needs additional...? (a) As a SAP, if you believe that ongoing services (in addition to follow-up tests) are needed...

  9. 49 CFR 40.303 - What happens if the SAP believes the employee needs additional treatment, aftercare, or support...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false What happens if the SAP believes the employee... the Return-to-Duty Process § 40.303 What happens if the SAP believes the employee needs additional...? (a) As a SAP, if you believe that ongoing services (in addition to follow-up tests) are needed...

  10. 49 CFR 40.303 - What happens if the SAP believes the employee needs additional treatment, aftercare, or support...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false What happens if the SAP believes the employee... the Return-to-Duty Process § 40.303 What happens if the SAP believes the employee needs additional...? (a) As a SAP, if you believe that ongoing services (in addition to follow-up tests) are needed...

  11. Effect of a laboratory surfactant on compatibility of type IV dental stones with addition-cured silicone impression materials.

    PubMed

    Tredwin, Christopher Jeremy; Nesbit, Michael; Butta, Rajeev; Moles, David R

    2008-06-01

    This study compared the effect of a surfactant on surface detail reproduction between combinations of addition-cured silicone impression materials and type IV stones. Six hundred impressions were made of a ruled test block using; Examix-NDS, Doric-Es Flo-Light, Panasil Contact Plus, Extrude Wash and President Plus Jet. Half of the impressions were treated with a surfactant (Aurofilm). Impressions were poured with type IV dental stones; Silky Rock, Fuji Rock, Suprastone and Vel-Mix and the 20 mu line was scored. A laboratory surfactant (Aurofilm) significantly reduced (P<0.01) compatibility with; (i) Examix-NDS and Suprastone, (ii) Examix-NDS and Velmix, (iii) Extrude Wash and Fuji Rock.

  12. Chemistry and materials science progress report. Weapons-supporting research and laboratory directed research and development: FY 1995

    SciTech Connect

    1996-04-01

    This report covers different materials and chemistry research projects carried out a Lawrence Livermore National Laboratory during 1995 in support of nuclear weapons programs and other programs. There are 16 papers supporting weapons research and 12 papers supporting laboratory directed research.

  13. Analysis of the addition of a crosslinking agent in pyrromethene-HEMA based photopolymerizable holographic recording materials

    NASA Astrophysics Data System (ADS)

    Blaya, S.; Acebal, P.; Carretero, L.; Madrigal, R. F.; Murciano, A.; Fimia, A.

    2011-06-01

    In this work, we present the analysis of a photopolymerizable system based on pyrromethene dye (PM567) acting as a photoinitiator and HEMA as monomer both of them dissolved in a dry polymeric matrix of PMMA. Previously, we reported the recording of diffraction gratings in this composition, resulting in diffraction efficiencies near 60 % with exposures of 1 J/cm2 in materials with thicknesses around 500 microns. Although, the mentioned response (best) was observed at low intensities but at higher ones lower diffraction efficiencies were reached. Furthermore, in all the studied cases inhibition periods with asymmetrical angular selectivity curves were obtained. Since, in order to solve the mentioned drawbacks, the aim of this work is to analyze the effect of the addition of a crosslinking agent (PETA) in a photopolymerizable holographic material based on a pyrromethene dye (PM567) acting as a photoinitiator and HEMA as monomer both of them dissolved in a dry polymeric matrix of PMMA. For this, diffraction gratings were recorded at different intensities and the energetic evolution of the diffraction efficiency as well as the observed inhibition period were studied as a function of the concentration of crosslinking agent. Moreover, the experimental angular selectivity curves were theoretically analyzed by the model of Kubota and Uchida, and as a result information such as the effective thickness, fringe bending and non-uniform index modulation against the thickness of grating was obtained.

  14. Delignified cellulosic material supported biocatalyst as freeze-dried product in alcoholic fermentation.

    PubMed

    Iconomopoulou, M; Kanellaki, M; Psarianos, K; Koutinas, A A

    2000-03-01

    Freeze-dried delignified cellulosic (DC) material supported biocatalyst is proposed as a suitable form of biocatalyst to be preserved. The alcoholic fermentation of glucose using freeze-dried immobilized cells is reported. Freeze-dried immobilized baker's yeast cells on DC material do not need any protective medium during freeze-drying. The effect of initial glucose concentration and temperature on the alcoholic fermentation kinetic parameters is reported in the present study. It was found that the freeze-dried immobilized cells ferment more quickly than free freeze-dried cells and have a lower fermentation rate as compared with wet immobilized cells. However, repeated batch fermentations showed freeze-dried immobilized cells to ferment at about the same fermentation rate as wet immobilized cells. The results indicate that the freeze-dried immobilized cells must be further studied to establish a process for the preservation of immobilized cells.

  15. Enzyme conversion of lignocellulosic plant materials for resource recovery in a Controlled Ecological Life Support System

    NASA Technical Reports Server (NTRS)

    Kohlmann, K. L.; Westgate, P.; Velayudhan, A.; Weil, J.; Sarikaya, A.; Brewer, M. A.; Hendrickson, R. L.; Ladisch, M. R.; Mitchell, C. A. (Principal Investigator)

    1996-01-01

    A large amount of inedible plant material composed primarily of the carbohydrate materials cellulose, hemicellulose, and lignin is generated as a result of plant growth in a Controlled Ecological Life-Support System (CELSS). Cellulose is a linear homopolymer of glucose, which when properly processed will yield glucose, a valuable sugar because it can be added directly to human diets. Hemicellulose is a heteropolymer of hexoses and pentoses that can be treated to give a sugar mixture that is potentially a valuable fermentable carbon source. Such fermentations yield desirable supplements to the edible products from hydroponically-grown plants such as rapeseed, soybean, cowpea, or rice. Lignin is a three-dimensionally branched aromatic polymer, composed of phenyl propane units, which is susceptible to bioconversion through the growth of the white rot fungus, Pluerotus ostreatus. Processing conditions, that include both a hot water pretreatment and fungal growth and that lead to the facile conversion of plant polysaccharides to glucose, are presented.

  16. Laser supported detonation wave source of atomic oxygen for aerospace material testing

    NASA Technical Reports Server (NTRS)

    Krech, Robert H.; Caledonia, George E.

    1990-01-01

    A pulsed high-flux source of nearly monoenergetic atomic oxygen was developed to perform accelerated erosion testing of spacecraft materials in a simulated low-earth orbit (LEO) environment. Molecular oxygen is introduced into an evacuated conical expansion nozzle at several atmospheres pressure through a pulsed molecular beam valve. A laser-induced breakdown is generated in the nozzle throat by a pulsed CO2 TEA laser. The resulting plasma is heated by the ensuing laser-supported detonation wave, and then it rapidly expands and cools. An atomic oxygen beam is generated with fluxes above 10 to the 18th atoms per pulse at 8 + or - 1.6 km/s with an ion content below 1 percent for LEO testing. Materials testing yielded the same surface oxygen enrichment in polyethylene samples as observed on the STS mission, and scanning electron micrographs of the irradiated polymer surfaces showed an erosion morphology similar to that obtained on low earth orbit.

  17. Enzyme conversion of lignocellulosic plant materials for resource recovery in a controlled ecological life support system

    NASA Astrophysics Data System (ADS)

    Kohlmann, K. L.; Westgate, P.; Velayudhan, A.; Weil, J.; Sarikaya, A.; Brewer, M. A.; Hendrickson, R. L.; Ladisch, M. R.

    1996-01-01

    A large amount of inedible plant material composed primarily of the carbohydrate materials cellulose, hemicellulose, and lignin is generated as a result of plant growth in a Controlled Ecological Life-Support System (CELSS). Cellulose is a linear homopolymer of glucose, which when properly processed will yield glucose, a valuable sugar because it can be added directly to human diets. Hemicellulose is a heteropolymer of hexoses and pentoses that can be treated to give a sugar mixture that is potentially a valuable fermentable carbon source. Such fermentations yield desirable supplements to the edible products from hydroponically-grown plants such as rapeseed, soybean, cowpea, or rice. Lignin is a three-dimensionally branched aromatic polymer, composed of phenyl propane units, which is susceptible to bioconversion through the growth of the white rot fungus, Pluerotus ostreatus. Processing conditions, that include both a hot water pretreatment and fungal growth and that lead to the facile conversion of plant polysaccharides to glucose, are presented.

  18. Effect of addition of antibiotics and an antioxidant on the stability of tissue reference materials for domoic acid, the amnesic shellfish poison.

    PubMed

    McCarron, Pearse; Burrell, Stephen; Hess, Philipp

    2007-04-01

    Five separate reference materials (RMs) were prepared from a mussel (Mytilus edulis) tissue containing domoic acid (DA) from scallop hepatopancreas (Pecten maximus). Homogenates were separately spiked with antibiotics, an antioxidant, or a combination of both. Control materials did not contain any additives and were prepared from lightly cooked and autoclaved mussel tissues. Stability studies were run over a 148-day period at three different temperature conditions: -20 degrees C, +4 degrees C and +40 degrees C. DA contents in all materials were characterised by HPLC-UV. Homogeneities were demonstrated at the beginning of the study, with coefficients of variance of less than 4% (n = 9). DA was stable at -20 degrees C in all materials. The control materials showed significant degradation after two days at +40 degrees C, and after eight days at +4 degrees C. Each of the materials containing additives demonstrated better stability during the initial period of the study. In addition there was no significant degradation in any of the materials with additives stored at +4 degrees C over the duration of the study. The material containing a combination of the antibiotics and the antioxidant displayed the best stability of all the materials. There was no significant reduction in DA concentration at all temperature conditions after eight days, and after 32 days the decrease at +40 degrees C was still <20 %. Following this, a DA laboratory reference material (LRM) was prepared and, based on previous results, spiked with both the antioxidant and antibiotics. A short-term stability study on this material gave similar results to the corresponding material in the additives study. This study shows that combined use of the additives investigated in the preparation of a mussel tissue reference material for DA ensures analyte stability for a period of up to eight days at temperatures of up to +40 degrees C, a condition that is particularly important when shipping test materials

  19. Effect of PEG additive on anode microstructure and cell performance of anode-supported MT-SOFCs fabricated by phase inversion method

    NASA Astrophysics Data System (ADS)

    Ren, Cong; Liu, Tong; Maturavongsadit, Panita; Luckanagul, Jittima Amie; Chen, Fanglin

    2015-04-01

    Anode-supported micro-tubular solid oxide fuel cells (MT-SOFCs) have been fabricated by phase inversion method. For the anode support preparation, N-methyl-2-pyrrolidone (NMP), polyethersulfone (PESf) and poly ethylene glycol (PEG) were applied as solvent, polymer binder and additive, respectively. The effect of molecular weight and amount of PEG additive on the thermodynamics of the casting solutions was characterized by measuring the coagulation value. Viscosity of the casting slurries was also measured and the influence of PEG additive on viscosity was studied and discussed. The presence of PEG in the casting slurry can significantly influence the final anode support microstructure. Based on the microstructure result and the measured gas permeation value, two anode supports were selected for cell fabrication. For cell with the anode support fabricated using slurry with PEG additive, a maximum cell power density of 704 mW cm-2 is obtained at 750 °C with humidified hydrogen as fuel and ambient air as oxidant; cell fabricated without any PEG additive shows the peak cell power density of 331 mW cm-2. The relationship between anode microstructure and cell performance was discussed.

  20. Bacterial biodegradation of melamine-contaminated aged soil: influence of different pre-culture media or addition of activation material.

    PubMed

    Hatakeyama, Takashi; Takagi, Kazuhiro

    2016-08-01

    This study aimed to investigate the biodegrading potential of Arthrobacter sp. MCO, Arthrobacter sp. CSP, and Nocardioides sp. ATD6 in melamine-contaminated upland soil (melamine: approx. 10.5 mg/kg dry weight) after 30 days of incubation. The soil sample used in this study had undergone annual treatment of lime nitrogen, which included melamine; it was aged for more than 10 years in field. When R2A broth was used as the pre-culture medium, Arthrobacter sp. MCO could degrade 55 % of melamine after 30 days of incubation, but the other strains could hardly degrade melamine (approximately 25 %). The addition of trimethylglycine (betaine) in soil as an activation material enhanced the degradation rate of melamine by each strain; more than 50 % of melamine was degraded by all strains after 30 days of incubation. In particular, strain MCO could degrade 72 % of melamine. When the strains were pre-cultured in R2A broth containing melamine, the degradation rate of melamine in soil increased remarkably. The highest (72 %) melamine degradation rate was noted when strain MCO was used with betaine addition.

  1. Dihydrogen addition in a dinuclear rare-earth metal hydride complex supported by a metalated TREN ligand.

    PubMed

    Venugopal, Ajay; Fegler, Waldemar; Spaniol, Thomas P; Maron, Laurent; Okuda, Jun

    2011-11-09

    The dinuclear lutetium dihydride dication supported by metalated tripodal ligands undergoes facile hydrogenolysis with H(2) to form a trihydride dication. Molecular orbital analysis shows that the LUMO is a bonding Lu···Lu orbital that is poised to activate dihydrogen.

  2. Testing of organic waste surrogate materials in support of the Hanford organic tank program. Final report

    SciTech Connect

    Turner, D.A.; Miron, Y.

    1994-01-01

    To address safety issues regarding effective waste management efforts of underground organic waste storage tanks at the Hanford Site, the Bureau of Mines conducted a series of tests, at the request of the Westinghouse Hanford company. In this battery of tests, the thermal and explosive characteristics of surrogate materials, chosen by Hanford, were determined. The surrogate materials were mixtures of inorganic and organic sodium salts, representing fuels and oxidants. The oxidants were sodium nitrate and sodium nitrite. The fuels were sodium salts of oxalate, citrate and ethylenediamine tetraacetic acid (EDTA). Polyethylene powder was also used as a fuel with the oxidant(s). Sodium aluminate was used as a diluent. In addition, a sample of FeCN, supplied by Hanford was also investigated.

  3. PREPARATION AND CHARACTERIZATION OF NANOSTRUCTURED GRANULAR SUPPORT PARTICLES AND CATALYTIC MATERIALS

    SciTech Connect

    Zhenchen Zhong

    2002-01-15

    We have set up successfully two experimental systems during the past time of the project. The first system is sol-gel chemical method for preparing {gamma}-Al{sub 2}O{sub 3}, SiO{sub 2}, Cr{sub 2}O{sub 3} granular support particles. The second system is the laser-induced solution deposition (LISD) technique for nanoparticle catalysts containing Fe/Cu, and Co/Cu on the granular support. We have successfully deposited {gamma}-Al{sub 2}O{sub 3}, SiO{sub 2}, Cr{sub 2}O{sub 3} granular support particles by sol-gel method and Co and CoO nanoparticles by LISD novel fabrication technique. The characterization methods we have used include scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM) and X-Ray diffraction (XRD). The research toward to the proposed direction is in good progress. We have given three presentations in national and local materials meetings and have submitted another two papers in another two key national meetings in nanotechnology and American Physical Annual March Meeting 2002. A couple of papers are in preparation.

  4. Assessment of rock wool as support material for on-site sanitation: hydrodynamic and mechanical characterization.

    PubMed

    Wanko, Adrien; Laurent, Julien; Bois, Paul; Mosé, Robert; Wagner-Kocher, Christiane; Bahlouli, Nadia; Tiffay, Serge; Braun, Bouke; Provo kluit, Pieter-Willem

    2016-01-01

    This study proposes mechanical and hydrodynamic characterization of rock wool used as support material in compact filter. A double-pronged approach, based on experimental simulation of various physical states of this material was done. First of all a scanning electron microscopy observation allows to highlight the fibrous network structure, the fibres sizing distribution and the atomic absorption spectrum. The material was essentially lacunar with 97 ± 2% of void space. Static compression tests on variably saturated rock wool samples provide the fact that the strain/stress behaviours depend on both the sample conditioning and the saturation level. Results showed that water exerts plastifying effect on mechanical behaviour of rock wool. The load-displacement curves and drainage evolution under different water saturation levels allowed exhibiting hydraulic retention capacities under stress. Finally, several tracer experiments on rock wool column considering continuous and batch feeding flow regime allowed: (i) to determine the flow model for each test case and the implications for water dynamic in rock wool medium, (ii) to assess the rock wool double porosity and discuss its advantages for wastewater treatment, (iii) to analyse the benefits effect for water treatment when the high level of rock wool hydric retention was associated with the plug-flow effect, and (iv) to discuss the practical contributions for compact filter conception and management.

  5. Materials derived from synthetic organo-clay complexes as novel hydrodesulfurization catalyst supports.

    SciTech Connect

    Carrado, K. A.; Marshall, C. L.; Brenner, J. R.; Song, K.; Chemistry

    1998-01-01

    A series of mesoporous synthetic organo-clay complexes has been prepared by hydrothermal crystallization of gels containing silica, magnesium hydroxide, lithium fluoride, and an organic of choice, followed by calcination to remove the organics. The organic serves to impart structural order to the inorganic network that does not disappear upon its removal. The choice of organic modifier can be used to control the pore structure of the resulting mesoporous materials. Pore size distributions appear in some cases to be related to the type of polymer packing upon clay formation in situ. These materials are being explored as Co Mo hydrodesulfurization (HDS) catalyst supports. Preliminary HDS results show performance commensurate with commercial catalysis for the mesoporous materials when a model heavy oil feed is used (1 wt% S as dibenzothiophene in hexadecane). Temperature programmed reduction experiments of used catalysts suggest a relationship between HDS activity and ease of reduction of the CoMo/clay catalysts. Reactivity of the CoMo clay also correlates with the percentage of mesopore volume remaining after reaction. Losses in mesopore volume are largely recouped by recalcination, suggesting that reversible coke is formed inside the pore structure of clays faster than inside conventional alumina.

  6. Unmanned Aircraft Systems: Additional Actions Needed to Improve Management and Integration of DOD Efforts to Support Warfighter Needs

    DTIC Science & Technology

    2008-11-01

    Services, House of Representatives UNMANNED AIRCRAFT SYSTEMS Additional Actions Needed to Improve Management and Integration of DOD Efforts to...Armed Services, House of Representatives The Department of Defense’s (DOD) use of unmanned aircraft systems (UAS) continues to increase. In 2000...unmanned aircraft systems This is a work of the U.S. government and is not subject to copyright protection in the United States. It may be reproduced

  7. Mitochondrial genome sequence and gene order of Sipunculus nudus give additional support for an inclusion of Sipuncula into Annelida

    PubMed Central

    Mwinyi, Adina; Meyer, Achim; Bleidorn, Christoph; Lieb, Bernhard; Bartolomaeus, Thomas; Podsiadlowski, Lars

    2009-01-01

    Background Mitochondrial genomes are a valuable source of data for analysing phylogenetic relationships. Besides sequence information, mitochondrial gene order may add phylogenetically useful information, too. Sipuncula are unsegmented marine worms, traditionally placed in their own phylum. Recent molecular and morphological findings suggest a close affinity to the segmented Annelida. Results The first complete mitochondrial genome of a member of Sipuncula, Sipunculus nudus, is presented. All 37 genes characteristic for metazoan mtDNA were detected and are encoded on the same strand. The mitochondrial gene order (protein-coding and ribosomal RNA genes) resembles that of annelids, but shows several derivations so far found only in Sipuncula. Sequence based phylogenetic analysis of mitochondrial protein-coding genes results in significant bootstrap support for Annelida sensu lato, combining Annelida together with Sipuncula, Echiura, Pogonophora and Myzostomida. Conclusion The mitochondrial sequence data support a close relationship of Annelida and Sipuncula. Also the most parsimonious explanation of changes in gene order favours a derivation from the annelid gene order. These results complement findings from recent phylogenetic analyses of nuclear encoded genes as well as a report of a segmental neural patterning in Sipuncula. PMID:19149868

  8. Design and analysis of a piezoelectric material based touch screen with additional pressure and its acceleration measurement functions

    NASA Astrophysics Data System (ADS)

    Chu, Xiang-Cheng; Liu, Jia-Yi; Gao, Ren-Long; Chang, Jie; Li, Long-Tu

    2013-12-01

    Touch screens are becoming more and more prevalent in everyday environments due to their convenience and humanized operation. In this paper, a piezoelectric material based touch screen is developed and investigated. Piezoelectric ceramics arrayed under the touch panel at the edges or corners are used as tactile sensors to measure the touch positioning point similarly to conventional touch screens. However, additional touch pressure and its acceleration performance can also be obtained to obtain a higher-level human-machine interface. The piezoelectric ceramics can also be added to a traditional touch screen structure, or they can be used independently to construct a novel touch screen with a high light transmittance approach to a transparent glass. The piezoelectric ceramics were processed from PZT piezoelectric ceramic powder into a round or rectangular shape. According to the varied touch position and physical press strength of a finger, or even a gloved hand or fingernail, the piezoelectric tactile sensors will have different output voltage responses. By calculating the ratio of different piezoelectric tactile sensors’ responses and summing up all piezoelectric tactile sensors’ output voltages, the touch point position, touch pressure and touch force acceleration can be detected. A prototype of such a touch screen is manufactured and its position accuracy, touch pressure and response speed are measured in detail. The experimental results show that the prototype has many advantages such as high light transmittance, low energy cost and high durability.

  9. Solar water disinfection (SODIS) of Escherichia coli, Enterococcus spp., and MS2 coliphage: effects of additives and alternative container materials.

    PubMed

    Fisher, Michael B; Iriarte, Mercedes; Nelson, Kara L

    2012-04-15

    The use of alternative container materials and added oxidants accelerated the inactivation of MS2 coliphage and Escherichia coli and Enterococcus spp. bacteria during solar water disinfection (SODIS) trials. Specifically, bottles made from polypropylene copolymer (PPCO), a partially UVB-transparent plastic, resulted in three-log inactivation of these organisms in approximately half the time required for disinfection in bottles made from PET, polycarbonate, or Tritan(®), which absorb most UVB light. Furthermore, the addition of 125 mg/L sodium percarbonate in combination with either citric acid or copper plus ascorbate tended to accelerate inactivation by factors of 1.4-19. Finally, it was observed that the inactivation of E. coli and enterococci derived from local wastewater was far slower than the inactivation of laboratory-cultured E. coli and Enterococcus spp., while the inactivation of MS2 was slowest of all. These results highlight the importance of UVB in SODIS under certain conditions, and also the greater sunlight resistance of some viruses and of bacteria of fecal origin, as compared to the laboratory-cultured bacteria commonly used to model their inactivation. Furthermore, this study illustrates promising new avenues for accelerating the inactivation of bacteria and viruses by solar disinfection.

  10. Application of the US decision support tool for materials and waste management

    SciTech Connect

    Thorneloe, Susan A. Weitz, Keith Jambeck, Jenna

    2007-07-01

    The US Environmental Protection Agency (US EPA) launched the Resource Conservation Challenge (RCC) in 2002 to help reduce waste and move towards more sustainable resource consumption. The objective of the RCC is to help communities, industries, and the public think in terms of materials management rather than waste disposal. Reducing cost, finding more efficient and effective strategies to manage municipal waste, and thinking in terms of materials management requires a holistic approach that considers life-cycle environmental tradeoffs. The US EPA's National Risk Management Research Laboratory has led the development of a municipal solid waste decision support tool (MSW-DST). The computer software can be used to calculate life-cycle environmental tradeoffs and full costs of different waste management or materials recovery programs. The environmental methodology is based on the use of life-cycle assessment and the cost methodology is based on the use of full-cost accounting. Life-cycle inventory (LCI) environmental impacts and costs are calculated from the point of collection, handling, transport, treatment, and disposal. For any materials that are recovered for recycling, offsets are calculated to reflect potential emissions savings from use of virgin materials. The use of the MSW-DST provides a standardized format and consistent basis to compare alternatives. This paper provides an illustration of how the MSW-DST can be used by evaluating ten management strategies for a hypothetical medium-sized community to compare the life-cycle environmental and cost tradeoffs. The LCI results from the MSW-DST are then used as inputs into another US EPA tool, the Tool for the reduction and assessment of chemical and other environmental impacts, to convert the LCI results into impact indicators. The goal of this paper is to demonstrate how the MSW-DST can be used to identify and balance multiple criteria (costs and environmental impacts) when evaluating options for materials and

  11. Materialism.

    PubMed

    Melnyk, Andrew

    2012-05-01

    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website.

  12. Piloting the Post-Entry Language Assessment: Outcomes from a New System for Supporting Research Candidates with English as an Additional Language

    ERIC Educational Resources Information Center

    Tynan, Liz; Johns, Kellie

    2015-01-01

    The Post-Entry Language Assessment (PELA) was introduced by the James Cook University Graduate Research School in February 2013 as a pilot programme to test a new mechanism for initiating post-enrolment support for research degree candidates who have English as an additional language. Language ability does not necessarily, on its own, predict…

  13. Coated mesh photocatalytic reactor for air treatment applications: comparative study of support materials.

    PubMed

    Passalía, Claudio; Nocetti, Emanuel; Alfano, Orlando; Brandi, Rodolfo

    2016-06-14

    An experimental comparative study of different meshes as support materials for photocatalytic applications in gas phase is presented. The photocatalytic oxidation of dichloromethane in air was addressed employing different coated meshes in a laboratory-scale, continuous reactor. Two fiberglass meshes and a stainless steel mesh were studied regarding the catalyst load, adherence, and catalytic activity. Titanium dioxide photocatalyst was immobilized on the meshes by dip-coating cycles. Results indicate the feasibility of the dichloromethane elimination in the three cases. When the number of coating cycles was doubled, the achieved conversion levels were increased twofold for stainless steel and threefold for the fiberglass meshes. One of the fiberglass meshes (FG2) showed the highest reactivity per mass of catalyst and per catalytic surface area.

  14. A new supporting material for fascia grafting during myringoplasty: polyglycolic acid sheets.

    PubMed

    Yamanaka, Toshiaki; Sawai, Yachiyo; Hosoi, Hiroshi

    2013-08-01

    We used polyglycolic acid (PGA) sheets, a reinforcing material, as supporting devices for securing the fascia instead of fibrin glue or Gelfoam in patients with tympanic membrane (TM) perforations. PGA sheets were placed lateral to the fascia graft attached using the underlay grafting technique in 6 patients. In each case, the PGA sheet had been macerated and had merged into the fascia within 1 week of the procedure. At 2 to 3 postoperative weeks, parts of the sheet had become dehydrated and detached from the fascia, revealing a new epithelialized TM underneath. Eventually, the sheet had disappeared, and complete epithelialization had been achieved at 4 to 5 postoperative weeks, resulting in the successful closure of the perforation. The repair of TM remained stable throughout the follow-up period of at least 6 months in all patients. These results suggest that PGA sheets have the potential to secure fascia grafts and to guide the epithelialization of new tissue.

  15. Gene expression suggests conserved aspects of Hox gene regulation in arthropods and provides additional support for monophyletic Myriapoda.

    PubMed

    Janssen, Ralf; Budd, Graham E

    2010-07-05

    Antisense transcripts of Ultrabithorax (aUbx) in the millipede Glomeris and the centipede Lithobius are expressed in patterns complementary to that of the Ubx sense transcripts. A similar complementary expression pattern has been described for non-coding RNAs (ncRNAs) of the bithoraxoid (bxd) locus in Drosophila, in which the transcription of bxd ncRNAs represses Ubx via transcriptional interference. We discuss our findings in the context of possibly conserved mechanisms of Ubx regulation in myriapods and the fly.Bicistronic transcription of Ubx and Antennapedia (Antp) has been reported previously for a myriapod and a number of crustaceans. In this paper, we show that Ubx/Antp bicistronic transcripts also occur in Glomeris and an onychophoran, suggesting further conserved mechanisms of Hox gene regulation in arthropods.Myriapod monophyly is supported by the expression of aUbx in all investigated myriapods, whereas in other arthropod classes, including the Onychophora, aUbx is not expressed. Of the two splice variants of Ubx/Antp only one could be isolated from myriapods, representing a possible further synapomorphy of the Myriapoda.

  16. The Astronomy Workshop: Computer Assisted Learning Tools with Instructor Support Materials and Student Activities

    NASA Astrophysics Data System (ADS)

    Deming, Grace; Hamilton, D.; Hayes-Gehrke, M.

    2006-12-01

    The Astronomy Workshop (http://janus.astro.umd.edu) is a collection of interactive World Wide Web tools that were developed under the direction of Doug Hamilton for use in undergraduate classes, as supplementary materials appropriate for grades 9-12, and by the general public. The philosophy of the website is to foster student and public interest in astronomy by capitalizing on their fascination with computers and the internet. Many of the tools were developed by graduate and undergraduate students at UMD. This website contains over 20 tools on topics including scientific notation, giant impacts, extrasolar planets, astronomical distances, planets, moons, comets, and asteroids. Educators around the country at universities, colleges, and secondary schools have used the Astronomy Workshop’s tools and activities as homework assignments, in-class demos, or extra credit. Since 2005, Grace Deming has assessed several of the Astronomy Workshop’s tools for clarity and effectiveness by interviewing students as they used tools on the website. Based on these interviews, Deming wrote student activities and instructor support materials and posted them to the website. Over the next three years, we will continue to interview students, develop web materials, and field-test activities. We are targeting classes in introductory undergraduate astronomy courses and grades 11-12 for our Spring 2007 field tests. We are interested in hearing your ideas on how we can make the Astronomy Workshop more appealing to educators, museum directors, specialty programs, and professors. This research is funded by NASA EPO grants NNG04GM18G and NNG06GGF99G.

  17. 18 CFR 347.1 - Material to support request for newly established or changed property account depreciation studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Material to support request for newly established or changed property account depreciation studies. 347.1 Section 347.1... REGULATIONS UNDER THE INTERSTATE COMMERCE ACT OIL PIPELINE DEPRECIATION STUDIES § 347.1 Material to...

  18. 18 CFR 347.1 - Material to support request for newly established or changed property account depreciation studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Material to support request for newly established or changed property account depreciation studies. 347.1 Section 347.1... REGULATIONS UNDER THE INTERSTATE COMMERCE ACT OIL PIPELINE DEPRECIATION STUDIES § 347.1 Material to...

  19. 18 CFR 347.1 - Material to support request for newly established or changed property account depreciation studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Material to support request for newly established or changed property account depreciation studies. 347.1 Section 347.1... REGULATIONS UNDER THE INTERSTATE COMMERCE ACT OIL PIPELINE DEPRECIATION STUDIES § 347.1 Material to...

  20. 18 CFR 347.1 - Material to support request for newly established or changed property account depreciation studies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Material to support request for newly established or changed property account depreciation studies. 347.1 Section 347.1... REGULATIONS UNDER THE INTERSTATE COMMERCE ACT OIL PIPELINE DEPRECIATION STUDIES § 347.1 Material to...

  1. Fish composition and species richness in eastern South American coastal lagoons: additional support for the freshwater ecoregions of the world.

    PubMed

    Petry, A C; Guimarães, T F R; Vasconcellos, F M; Hartz, S M; Becker, F G; Rosa, R S; Goyenola, G; Caramaschi, E P; Díaz de Astarloa, J M; Sarmento-Soares, L M; Vieira, J P; Garcia, A M; Teixeira de Mello, F; de Melo, F A G; Meerhoff, M; Attayde, J L; Menezes, R F; Mazzeo, N; Di Dario, F

    2016-07-01

    The relationships between fish composition, connectivity and morphometry of 103 lagoons in nine freshwater ecoregions (FEOW) between 2·83° S and 37·64° S were evaluated in order to detect possible congruence between the gradient of species richness and similarities of assemblage composition. Most lagoons included in the study were <2 km(2) , with a maximum of 3975 km(2) in surface area. Combined surface area of all lagoons included in the study was 5411 km(2) . Number of species varied locally from one to 76. A multiple regression revealed that latitude, attributes of morphometry and connectivity, and sampling effort explained a large amount of variability in species richness. Lagoon area was a good predictor of species richness except in low latitude ecoregions, where lagoons are typically small-sized and not affected by marine immigrants, and where non-native fish species accounted for a significant portion of species richness. Relationships between species and area in small-sized lagoons (<2 km(2) ) is highly similar to the expected number in each ecoregion, with systems located between 18·27° S and 30·15° S attaining higher levels of species richness. Similarities in species composition within the primary, secondary and peripheral or marine divisions revealed strong continental biogeographic patterns only for species less tolerant or intolerant to salinity. Further support for the FEOW scheme in the eastern border of South America is therefore provided, and now includes ecotonal systems inhabited simultaneously by freshwater and marine species of fishes.

  2. Systematic Dissection of Coding Exons at Single Nucleotide Resolution Supports an Additional Role in Cell-Specific Transcriptional Regulation

    PubMed Central

    Kim, Mee J.; Findlay, Gregory M.; Martin, Beth; Zhao, Jingjing; Bell, Robert J. A.; Smith, Robin P.; Ku, Angel A.; Shendure, Jay; Ahituv, Nadav

    2014-01-01

    In addition to their protein coding function, exons can also serve as transcriptional enhancers. Mutations in these exonic-enhancers (eExons) could alter both protein function and transcription. However, the functional consequence of eExon mutations is not well known. Here, using massively parallel reporter assays, we dissect the enhancer activity of three liver eExons (SORL1 exon 17, TRAF3IP2 exon 2, PPARG exon 6) at single nucleotide resolution in the mouse liver. We find that both synonymous and non-synonymous mutations have similar effects on enhancer activity and many of the deleterious mutation clusters overlap known liver-associated transcription factor binding sites. Carrying a similar massively parallel reporter assay in HeLa cells with these three eExons found differences in their mutation profiles compared to the liver, suggesting that enhancers could have distinct operating profiles in different tissues. Our results demonstrate that eExon mutations could lead to multiple phenotypes by disrupting both the protein sequence and enhancer activity and that enhancers can have distinct mutation profiles in different cell types. PMID:25340400

  3. Direct Digital Manufacturing of Integrated Naval Systems Using Ultrasonic Consolidation, Support Material Deposition and Direct Write Technologies

    DTIC Science & Technology

    2012-02-17

    with an integrated " tool changer " capable of interchangeably using a "direct write tool " for electronic material deposition, a "material extrusion head...Pump Fig. 26. The nScrypt direct write "Smart Pump" system (www.nscryptinc.com) Direct Write Deposition & CNC Milling Flexible FDM Machine Heated...oflntegrated Naval Systems Using Ultrasonic Consolidation, Support Material Deposition and Direct Write Technologies 5a. CONTRACT NUMBER N00014-07-1-0633

  4. Supported Lipid Bilayers for the Generation of Dynamic Cell-Material Interfaces.

    PubMed

    van Weerd, Jasper; Karperien, Marcel; Jonkheijm, Pascal

    2015-12-30

    Supported lipid bilayers (SLB) offer unique possibilities for studying cellular membranes and have been used as a synthetic architecture to interact with cells. Here, the state-of-the-art in SLB-based technology is presented. The fabrication, analysis, characteristics and modification of SLBs are described in great detail. Numerous strategies to form SLBs on different substrates, and the means to patteren them, are described. The use of SLBs as model membranes for the study of membrane organization and membrane processes in vitro is highlighted. In addition, the use of SLBs as a substratum for cell analysis is presented, with discrimination between cell-cell and cell-extracellular matrix (ECM) mimicry. The study is concluded with a discussion of the potential for in vivo applications of SLBs.

  5. IWRM decision support with material flow analysis: consideration of urban system input.

    PubMed

    Terekhanova, T A; Helm, B; Traenckner, J; Krebs, P

    2012-01-01

    A review of material flow analysis (MFA) tools, comparison of case studies and analysis of approximately 20 MFA tools (static, semi-empirical models) are performed. The evaluation of the quantification procedures revealed several deficits in the approaches. The following principal complications for a reliable quantification of inputs from the urban water system are identified: (1) frequently insufficient data for urban system model validation (e.g. combined sewer overflow (CSO) discharges); (2) the necessity for additionally quantifying diffuse sources in order to verify modelling results at basin scale, where both input pathways occur, and (3) the contradictions arising when describing the highly dynamic urban system with the help of static MFA models. However, a wise selection of appropriate calculation procedures with regard to the concrete systems characteristics and available data can minimize the model deviations significantly. Criteria and suggestions for designing adapted quantification procedures are given.

  6. Method to develop data supporting consequence analyses of transporting nuclear materials in the United States

    SciTech Connect

    Reese, R.T.; Sandoval, R.P.

    1980-01-01

    The Transportation System Safety Evaluation (TSSE) program at Sandia National Laboratories' Transportation Technology Center was initiated to provide the necessary information on source terms for nuclear materials subjected to extreme environments. The techniques for derivation of source terms for the fuel alone has been described as well as the outline for package response. An additional facet of this problem is the development of analytical methods to describe the transport of the released radionuclides from the fuel rods to possible release points. This work is also covered in the TSSE program. Not all the work required will be performed or funded by Sandia; rather existing work will be sought out and ongoing work will be utilized in an attempt to unify the presentation of data and thus increase its usefulness.

  7. Does social support in addition to ART make a difference? Comparison of households with TASO and MOH PLWHA in Central Uganda.

    PubMed

    Abimanyi-Ochom, Julie; Lorgelly, Paula; Hollingsworth, Bruce; Inder, Brett

    2013-01-01

    Social support in addition to antiretroviral therapy (ART) has been indicated to be beneficial to person living with HIV/AIDS (PLWHA) and their families, but very few ART service providers go beyond ART. This study investigates whether receipt of social support in addition to ART for PLWHA makes the households that they reside in better off than households that have PLWHA but are without social support. The analysis uses data comprising of 450 households, which is a sub-sample from the 2010/2011 Centre for Health Economics Ugandan HIV Survey, a cross-sectional survey of 596 households that was undertaken in Uganda. Data were collected from households of clients that obtained ART from two major ART service providers in Central Uganda; The AIDS Support Organisation (TASO) and Ministry of Health (MOH), Uganda. Probit models and ordinary least squares regressions are employed to compare outcomes for individuals from households with a TASO or MOH client. Outcomes for individuals in households with a TASO PLWHA are hypothesised to be superior to those from households with an MOH PLWHA given that the benefits from social support accrue not only to the PLWHA but also to the household and communities they belong to. The results confirm that individuals from a household with a TASO PLWHA are better off in terms of physical health outcomes including better productivity as non-wage labour hours and having more cash in hand and having savings. The findings highlight the importance of additional support to HIV/AIDS clients and have implications for supplementation of ART service provision with other services to maximise the benefits from ART in resource constrained countries like Uganda.

  8. 36 CFR 1290.4 - Types of materials included in scope of assassination record and additional records and information.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Types of materials included..., Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION JFK ASSASSINATION RECORDS... documentary material; (b) Photographs; (c) Motion pictures; (d) Sound and video recordings; (e)...

  9. 36 CFR 1290.4 - Types of materials included in scope of assassination record and additional records and information.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Types of materials included..., Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION JFK ASSASSINATION RECORDS... documentary material; (b) Photographs; (c) Motion pictures; (d) Sound and video recordings; (e)...

  10. 36 CFR 1290.4 - Types of materials included in scope of assassination record and additional records and information.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Types of materials included..., Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION JFK ASSASSINATION RECORDS... documentary material; (b) Photographs; (c) Motion pictures; (d) Sound and video recordings; (e)...

  11. 21 CFR 570.14 - Indirect food additives resulting from packaging materials for animal feed and pet food.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... materials for animal feed and pet food. 570.14 Section 570.14 Food and Drugs FOOD AND DRUG ADMINISTRATION... pet food. Regulations providing for the use of food packaging materials in parts 174 through 179 of... and pet food....

  12. 21 CFR 570.13 - Indirect food additives resulting from packaging materials prior sanctioned for animal feed and...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... materials prior sanctioned for animal feed and pet food. 570.13 Section 570.13 Food and Drugs FOOD AND DRUG... prior sanctioned for animal feed and pet food. Regulations providing for the use of food packaging... packaging materials used for animal feed and pet food....

  13. 21 CFR 570.14 - Indirect food additives resulting from packaging materials for animal feed and pet food.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... materials for animal feed and pet food. 570.14 Section 570.14 Food and Drugs FOOD AND DRUG ADMINISTRATION... pet food. Regulations providing for the use of food packaging materials in parts 174 through 179 of... and pet food....

  14. 21 CFR 570.13 - Indirect food additives resulting from packaging materials prior sanctioned for animal feed and...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... materials prior sanctioned for animal feed and pet food. 570.13 Section 570.13 Food and Drugs FOOD AND DRUG... prior sanctioned for animal feed and pet food. Regulations providing for the use of food packaging... packaging materials used for animal feed and pet food....

  15. Enzyme Immobilization: An Overview on Methods, Support Material, and Applications of Immobilized Enzymes.

    PubMed

    Sirisha, V L; Jain, Ankita; Jain, Amita

    2016-01-01

    Immobilized enzymes can be used in a wide range of processes. In recent years, a variety of new approaches have emerged for the immobilization of enzymes that have greater efficiency and wider usage. During the course of the last two decades, this area has rapidly expanded into a multidisciplinary field. This current study is a comprehensive review of a variety of literature produced on the different enzymes that have been immobilized on various supporting materials. These immobilized enzymes have a wide range of applications. These include applications in the sugar, fish, and wine industries, where they are used for removing organic compounds from waste water. This study also reviews their use in sophisticated biosensors for metabolite control and in situ measurements of environmental pollutants. Immobilized enzymes also find significant application in drug metabolism, biodiesel and antibiotic production, bioremediation, and the food industry. The widespread usage of immobilized enzymes is largely due to the fact that they are cheaper, environment friendly, and much easier to use when compared to equivalent technologies.

  16. Online Condition Monitoring of Bearings to Support Total Productive Maintenance in the Packaging Materials Industry

    PubMed Central

    Gligorijevic, Jovan; Gajic, Dragoljub; Brkovic, Aleksandar; Savic-Gajic, Ivana; Georgieva, Olga; Di Gennaro, Stefano

    2016-01-01

    The packaging materials industry has already recognized the importance of Total Productive Maintenance as a system of proactive techniques for improving equipment reliability. Bearing faults, which often occur gradually, represent one of the foremost causes of failures in the industry. Therefore, detection of their faults in an early stage is quite important to assure reliable and efficient operation. We present a new automated technique for early fault detection and diagnosis in rolling-element bearings based on vibration signal analysis. Following the wavelet decomposition of vibration signals into a few sub-bands of interest, the standard deviation of obtained wavelet coefficients is extracted as a representative feature. Then, the feature space dimension is optimally reduced to two using scatter matrices. In the reduced two-dimensional feature space the fault detection and diagnosis is carried out by quadratic classifiers. Accuracy of the technique has been tested on four classes of the recorded vibrations signals, i.e., normal, with the fault of inner race, outer race, and ball operation. The overall accuracy of 98.9% has been achieved. The new technique can be used to support maintenance decision-making processes and, thus, to increase reliability and efficiency in the industry by preventing unexpected faulty operation of bearings. PMID:26938541

  17. Online Condition Monitoring of Bearings to Support Total Productive Maintenance in the Packaging Materials Industry.

    PubMed

    Gligorijevic, Jovan; Gajic, Dragoljub; Brkovic, Aleksandar; Savic-Gajic, Ivana; Georgieva, Olga; Di Gennaro, Stefano

    2016-03-01

    The packaging materials industry has already recognized the importance of Total Productive Maintenance as a system of proactive techniques for improving equipment reliability. Bearing faults, which often occur gradually, represent one of the foremost causes of failures in the industry. Therefore, detection of their faults in an early stage is quite important to assure reliable and efficient operation. We present a new automated technique for early fault detection and diagnosis in rolling-element bearings based on vibration signal analysis. Following the wavelet decomposition of vibration signals into a few sub-bands of interest, the standard deviation of obtained wavelet coefficients is extracted as a representative feature. Then, the feature space dimension is optimally reduced to two using scatter matrices. In the reduced two-dimensional feature space the fault detection and diagnosis is carried out by quadratic classifiers. Accuracy of the technique has been tested on four classes of the recorded vibrations signals, i.e., normal, with the fault of inner race, outer race, and ball operation. The overall accuracy of 98.9% has been achieved. The new technique can be used to support maintenance decision-making processes and, thus, to increase reliability and efficiency in the industry by preventing unexpected faulty operation of bearings.

  18. Supporting Technology for Chain of Custody of Nuclear Weapons and Materials throughout the Dismantlement and Disposition Processes

    SciTech Connect

    Bunch, Kyle J.; Jones, Anthony M.; Ramuhalli, Pradeep; Benz, Jacob M.; Denlinger, Laura Schmidt

    2014-05-04

    The ratification and ongoing implementation of the New START Treaty have been widely regarded as noteworthy global security achievements for both the Obama Administration and the Putin (formerly Medvedev) regime. But deeper cuts that move beyond the United States and Russia to engage the P-5 and other nuclear weapons possessor states are envisioned under future arms control regimes, and are indeed required for the P-5 in accordance with their Article VI disarmament obligations in the Nuclear Non-Proliferation Treaty. Future verification needs will include monitoring the cessation of production of new fissile material for weapons, monitoring storage of warhead components and fissile materials and verifying dismantlement of warheads, pits, secondary stages, and other materials. A fundamental challenge to implementing a nuclear disarmament regime is the ability to thwart unauthorized material diversion throughout the dismantlement and disposition process through strong chain of custody implementation. Verifying the declared presence, or absence, of nuclear materials and weapons components throughout the dismantlement and disposition lifecycle is a critical aspect of the disarmament process. From both the diplomatic and technical perspectives, verification under these future arms control regimes will require new solutions. Since any acceptable verification technology must protect sensitive design information and attributes to prevent the release of classified or other proliferation-sensitive information, non-nuclear non-sensitive modalities may provide significant new verification tools which do not require the use of additional information barriers. Alternative verification technologies based upon electromagnetic and acoustics could potentially play an important role in fulfilling the challenging requirements of future verification regimes. For example, researchers at the Pacific Northwest National Laboratory (PNNL) have demonstrated that low frequency electromagnetic

  19. A review of the work of the EU Reference Laboratory supporting the authorisation process of feed additives in the EU. [corrected].

    PubMed

    von Holst, Christoph; Robouch, Piotr; Bellorini, Stefano; González de la Huebra, María José; Ezerskis, Zigmas

    2016-01-01

    This paper describes the operation of the European Union Reference Laboratory for Feed Additives (EURL) and its role in the authorisation procedure of feed additives in the European Union. Feed additives are authorised according to Regulation (EC) No. 1831/2003, which introduced a completely revised authorisation procedure and also established the EURL. The regulations authorising feed additives contain conditions of use such as legal limits of the feed additives, which require the availability of a suitable method of analysis for official control purposes under real world conditions. It is the task of the EURL to evaluate the suitability of analytical methods as proposed by the industry for this purpose. Moreover, the paper shows that one of the major challenges is the huge variety of the methodology applied in feed additive analysis, thus requiring expertise in quite different analytical areas. In order to cope with this challenge, the EURL is supported by a network of national reference laboratories (NRLs) and only the merged knowledge of all NRLs allows for a scientifically sound assessment of the analytical methods.

  20. Using supported Au nanoparticles as starting material for preparing uniform Au/Pd bimetallic catalysts.

    PubMed

    Villa, Alberto; Wang, Di; Su, Dangsheng; Veith, Gabriel M; Prati, Laura

    2010-03-07

    One of the best methods for producing bulk homogeneous (composition) supported bimetallic AuPd clusters involves the immobilization of a protected Au seed followed by the addition of Pd. This paper investigates the importance of this gold seed in controlling the resulting bimetallic AuPd clusters structures, sizes and catalytic activities by investigating three different gold seeds. Uniform Au-Pd alloy were obtained when a steric/electrostatic protecting group, poly(vinyl alcohol) (PVA), was used to form the gold clusters on activated carbon (AC). In contrast Au/AC precursors prepared using Au nanoparticles with only electrostatic stabilization (tetrakis(hydroxypropyl)phosphonium chloride (THPC)), or no stabilization (magnetron sputtering) produced inhomogeneous alloys and segregation of the gold and palladium. The uniform alloyed catalyst (Pd@Au(PVA)/AC) is the most active and selective catalyst, while the inhomogenous catalysts are less active and selective. Further study of the PVA protected Au clusters revealed that the amount of PVA used is also critical for the preparation of uniform alloyed catalyst, their stability, and their catalytic activity.

  1. Using supported Au nanoparticles as starting material for preparing uniform Au/Pd bimetallic catalysts

    SciTech Connect

    Villa, Alberto; Prati, Laura; Su, Dangshen; Wang, Di; Veith, Gabriel M

    2010-01-01

    One of the best methods for producing bulk homogeneous (composition) supported bimetallic AuPd clusters involves the immobilization of a protected Au seed followed by the addition of Pd. This paper investigates the importance of this gold seed in controlling the resulting bimetallic AuPd clusters structures, sizes and catalytic activities by investigating three different gold seeds. Uniform Au-Pd alloy were obtained when a steric/electrostatic protecting group, poly(vinyl alcohol) (PVA), was used to form the gold clusters on activated carbon (AC). In contrast Au/AC precursors prepared using Au nanoparticles with only electrostatic stabilization (tetrakis(hydroxypropyl)phosphonium chloride (THPC)), or no stabilization (magnetron sputtering) produced inhomogeneous alloys and segregation of the gold and palladium. The uniform alloyed catalyst (Pd{at}Au{sub PVA}/AC) is the most active and selective catalyst, while the inhomogenous catalysts are less active and selective. Further study of the PVA protected Au clusters revealed that the amount of PVA used is also critical for the preparation of uniform alloyed catalyst, their stability, and their catalytic activity.

  2. Materials for sustained and controlled release of nutrients and molecules to support plant growth.

    PubMed

    Davidson, Drew; Gu, Frank X

    2012-02-01

    Controlled release fertilizers (CRFs) are a branch of materials that are designed to improve the soil release kinetics of chemical fertilizers to address problems stemming losses from runoff or other factors. Current CRFs are used but only in a limited market due to relatively high costs and doubts about their abilities to result in higher yields and increased profitability for agricultural businesses. New technologies are emerging that promise to improve the efficacy of CRFs to add additional functionality and reduce cost to make CRFs a more viable alternative to traditional chemical fertilizer treatment. CRFs that offer ways of reducing air and water pollution from fertilizer treatments, improving the ability of plants to access required nutrients, improving water retention to increase drought resistance, and reducing the amount of fertilizer needed to provide maximum crop yields are under development. A wide variety of different strategies are being considered to tackle this problem, and each approach offers different advantages and drawbacks. Agricultural industries will soon be forced to move toward more efficient and sustainable practices to respond to increasing fertilizer cost and desire for sustainable growing practices. CRFs have the potential to solve many problems in agriculture and help enable this shift while maintaining profitability.

  3. The Nuclear Fuel Services, Inc. program to support disposition of enriched uranium-bearing materials

    SciTech Connect

    Schutt, Stephen M.; Jacob, Norman P.

    2007-07-01

    The disposition of surplus nuclear materials has become one of the most pressing issues of our time. Numerous agencies have invoked programs with the purpose of removing such materials from various international venues and disposing these materials in a manner that achieves non-proliferability. This paper describes the Nuclear Fuel Services, Inc (NFS) Nuclear Material Disposition Program, which to date has focused on a variety of Special Nuclear Material (SNM), in particular uranium of various enrichments. The major components of this program are discussed, with emphasis on recycle and return of material to the nuclear fuel cycle. (authors)

  4. Preparation and adsorption behavior of berberine hydrochloride imprinted polymers by using silica gel as sacrificed support material

    NASA Astrophysics Data System (ADS)

    Li, Hui; Li, Yuzhuo; Li, Zhiping; Peng, Xiyang; Li, Yanan; Li, Gui; Tan, Xianzhou; Chen, Gongxi

    2012-03-01

    Preparation of berberine hydrochloride (B-Cl) imprinted polymers (MIPs) based on surface imprinting technique with silica gel as sacrificial support material was performed successfully by using B-Cl as template, methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) as functional monomer and cross-linker, respectively. The prepared polymers were characterized by Fourier transmission infrared spectrometry (FTIR) and scanning electron microscopy (SEM). Adsorption behavior of the MIPs for the template and its structural analogues was investigated. Sites distribution on the surface of MIPs was explored by using different isotherm adsorption models and thermodynamic parameters for the adsorption of B-Cl on the MIPs determined. Sample application and reusability for the MIPs was also evaluated. Results indicated the strong adsorption and high selectivity of the MIPs for B-Cl. Saturated adsorption capacity reached 27.2 μmol g-1 and the selectivity coefficient of the MIPs for B-Cl relative to jatrorrhizine hydrochloride (J-Cl) and palmatine palmatus hydrochloride (P-Cl) are 3.70 and 6.03, respectively. In addition, the MIPs were shown with good reusability and selectively retention ability in sample application.

  5. The influence of collagen support and ionic species on the morphology of collagen/hydroxyapatite composite materials

    SciTech Connect

    Ficai, Anton; Andronescu, Ecaterina; Voicu, Georgeta; Ghitulica, Cristina; Ficai, Denisa

    2010-04-15

    The purpose of this investigation is to study the influence of collagenous supports and ionic species on the precipitation of hydroxyapatite (HA) from aqueous solutions. To this end, we obtained hydroxyapatite by co-precipitation from a solution of calcium hydroxide and sodium dihydrogenophosphate. The formation of HA was studied by energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The results of this study indicate that the morphology of hydroxyapatite is highly influenced by the support material and the ionic species present. The obtained materials were studied by scanning electron microscopy (SEM).

  6. Full Mouth Oral Rehabilitation by Maxillary Implant Supported Hybrid Denture Employing a Fiber Reinforced Material Instead of Conventional PMMA

    PubMed Central

    Qamheya, Ala Hassan A.; Yeniyol, Sinem; Arısan, Volkan

    2015-01-01

    Many people have life-long problems with their dentures, such as difficulties with speaking and eating, loose denture, and sore mouth syndrome. The evolution of dental implant supported prosthesis gives these patients normal healthy life for their functional and esthetic advantages. This case report presents the fabrication of maxillary implant supported hybrid prosthesis by using Nanofilled Composite (NFC) material in teeth construction to rehabilitate a complete denture wearer patient. PMID:26557392

  7. Influence of nanographene platelets (NGP) incorporation on Fe3O4 nanoparticles as materials additives for enhancement thermal properties stearic acid

    NASA Astrophysics Data System (ADS)

    Nuryadin, M. K.; Andiarto, R.; Taufik, A.; Saleh, R.

    2016-11-01

    In this work, Fe3O4 nanoparticles, and Fe3O4/NGP composite were used as material additive for enhancement thermal properties of stearic acid (SA). The both material additive were synthesized using sol-gel method. Phase change material (PCM) composites SA-Fe3O4 and Sa-Fe3O4/NGP mixtures were made through the dispersion technique with three different weight % ratio of material additives into stearic acid: 1 wt.%, 3 wt.%, and 5 wt.%. X-Ray Diffractometer (XRD) and Fourier Transform Infrared (FTIR) spectroscopy were used to investigate the structural properties. Magnetic properties also measured by vibrating sample magnetometer (VSM) to see influence of NGP in PCM composites. Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) were used in order to analyse the thermal properties of the samples. The results show an enhancement of the latent heat, thermal stability as well as specific heat by the presence of material additives in SA. Compare to SA- Fe3O4, SA-Fe3O4/NGP show better improvement in enhancement of thermal performance of SA. The improvement by about 41.2% in specific heat and 21.2% in latent heat.

  8. Water-soluble metal working fluids additives derived from the esters of acid anhydrides with higher alcohols for aluminum alloy materials.

    PubMed

    Yamamoto, Syutaro; Tomoda, Hideyuki; Watanabe, Shoji

    2007-01-01

    Water-soluble metal working fluids are used for processing of aluminum alloy materials. This short article describes properties of new additives in water-soluble metal working fluids for aluminum alloy materials. Many half esters or diesters were prepared from the reactions of higher alcohols with acid anhydrides. Interestingly, diesters of PTMG (tetrahydrofuran oligomer, MW = 650 and 1000) and polybutylene oxide (MW = 650) with maleic anhydride and succinic anhydride showed both of an excellent anti-corrosion property for aluminum alloy and a good hard water tolerance. The industrial soluble type processing oils including these additives also showed anti-corrosion property and hard water tolerance.

  9. Bifunctional heterogeneous catalysis of silica-alumina-supported tertiary amines with controlled acid-base interactions for efficient 1,4-addition reactions.

    PubMed

    Motokura, Ken; Tanaka, Satoka; Tada, Mizuki; Iwasawa, Yasuhiro

    2009-10-19

    We report the first tunable bifunctional surface of silica-alumina-supported tertiary amines (SA-NEt(2)) active for catalytic 1,4-addition reactions of nitroalkanes and thiols to electron-deficient alkenes. The 1,4-addition reaction of nitroalkanes to electron-deficient alkenes is one of the most useful carbon-carbon bond-forming reactions and applicable toward a wide range of organic syntheses. The reaction between nitroethane and methyl vinyl ketone scarcely proceeded with either SA or homogeneous amines, and a mixture of SA and amines showed very low catalytic activity. In addition, undesirable side reactions occurred in the case of a strong base like sodium ethoxide employed as a catalytic reagent. Only the present SA-supported amine (SA-NEt(2)) catalyst enabled selective formation of a double-alkylated product without promotions of side reactions such as an intramolecular cyclization reaction. The heterogeneous SA-NEt(2) catalyst was easily recovered from the reaction mixture by simple filtration and reusable with retention of its catalytic activity and selectivity. Furthermore, the SA-NEt(2) catalyst system was applicable to the addition reaction of other nitroalkanes and thiols to various electron-deficient alkenes. The solid-state magic-angle spinning (MAS) NMR spectroscopic analyses, including variable-contact-time (13)C cross-polarization (CP)/MAS NMR spectroscopy, revealed that acid-base interactions between surface acid sites and immobilized amines can be controlled by pretreatment of SA at different temperatures. The catalytic activities for these addition reactions were strongly affected by the surface acid-base interactions.

  10. Sulfate reduction in sulfuric material after re-flooding: Effectiveness of organic carbon addition and pH increase depends on soil properties.

    PubMed

    Yuan, Chaolei; Fitzpatrick, Rob; Mosley, Luke M; Marschner, Petra

    2015-11-15

    Sulfuric material is formed upon oxidation of sulfidic material; it is extremely acidic, and therefore, an environmental hazard. One option for increasing pH of sulfuric material may be stimulation of bacterial sulfate reduction. We investigated the effects of organic carbon addition and pH increase on sulfate reduction after re-flooding in ten sulfuric materials with four treatments: control, pH increase to 5.5 (+pH), organic carbon addition with 2% w/w finely ground wheat straw (+C), and organic carbon addition and pH increase (+C+pH). After 36 weeks, in five of the ten soils, only treatment +C+pH significantly increased the concentration of reduced inorganic sulfur (RIS) compared to the control and increased the soil pore water pH compared to treatment+pH. In four other soils, pH increase or/and organic carbon addition had no significant effect on RIS concentration compared to the control. The RIS concentration in treatment +C+pH as percentage of the control was negatively correlated with soil clay content and initial nitrate concentration. The results suggest that organic carbon addition and pH increase can stimulate sulfate reduction after re-flooding, but the effectiveness of this treatment depends on soil properties.

  11. Materials/manufacturing support element for the Advanced Turbine Systems Program

    SciTech Connect

    Karnitz, M.A.; Hoffman, E.E.; Parks, W.P.

    1994-12-31

    In 1993, DOE initiated a program to develop advanced gas turbines for power generation in utility and industrial applications. A materials/manufacturing plan was developed in several stages with input from gas turbine manufacturers, materials suppliers, universities, and government laboratories. This plan was developed by a small advanced materials and turbine technology team over a 6-month period. The technology plan calls for initiation of several high priority projects in FY 1995. The technical program for the materials/manufacturing element focuses on generic materials issues, components, and manufacturing processes. Categories include coatings and process development, turbine airfoil development, ceramics adaptation, directional solidification and single crystal airfoils manufactoring technology, materials characterization, catalytic combustor materials, and technology information exchange.

  12. One-step microwave-assisted asymmetric cyclisation/hydrogenation of citronellal to menthols using supported nanoparticles on mesoporous materials.

    PubMed

    Balu, Alina Mariana; Campelo, Juan Manuel; Luque, Rafael; Romero, Antonio Angel

    2010-06-21

    The selective conversion of citronellal to menthols, with good diastereoselectivities to (-)-menthol for the case of (+)-citronellal as starting material, can effectively be carried out in a one-step reaction under microwave irradiation catalysed by supported nanoparticles on mesoporous materials. 2% Pt/Ga-MCM-41 was found to be the optimum catalyst for the reaction, with a quantitative conversion of starting material and selectivities above 85% to menthols obtained in short reaction times (typically 15 min). These results constitute the first report of a simple microwave-assisted one-step cyclisation/hydrogenation process for the production of menthols.

  13. Mechanical and Structural Behavior of Granular Material Packed Beds for Space Life Support System Applications

    NASA Technical Reports Server (NTRS)

    Malla, Ramesh B.; Anandakumar, Ganesh

    2005-01-01

    Long-term human mission to space, such as living in International Space Station (ISS), Lunar, and Martian bases, and travel to Mars, must m ake use of Advanced Life Support Systems (ALSS) to generate and recycle critical life supporting elements like oxygen and water. Oxygen Gen eration Assembly (OGA) and Water Processor Assembly (WPA), critical c omponents of ALSS, make use of series of granular material packed beds for generation and recycling of oxygen and water. Several granular m aterials can be used for generation, recycling, processing and recovery of oxygen and water. For example, they may include soft bed media, e.g. ion exchange resins for oxygen generation assembly and hard bed media such as, activated alumina, magchem (Magnesium oxide) and activa ted carbon to remove organic species like ethanol, methanol, and urea from wastewater in Water recovery/processing assembly. These beds are generally packed using a plate-spring mechanism to provide sufficien t compaction to the bed media throughout the course of operation. This paper presents results from an experimental study of a full-scale, 3 8.1 cm (15 inches) long and 3.7 cm (1.44 inches) diameter. activated alumina bed enclosed in a cylinder determining its force-displacement behavior, friction mobilizing force, and axial normal stress distribu tion under various axially applied loads and at different levels of packing. It is observed that force-displacement behavior is non-linear for low compaction level and becomes linear with increase in compaction of the bed media. Axial normal stress distribution along the length of the bed media decreased non-linearly with increase in depth from the loading end of the granular media. This paper also presents experimental results on the amount of particulates generated corresponding to various compaction levels. Particulates generated from each of the tests were measured using standard US sieves. It was found that the p articulates and the overall displacement of

  14. 18 CFR 347.1 - Material to support request for newly established or changed property account depreciation studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... request for newly established or changed property account depreciation studies. 347.1 Section 347.1... REGULATIONS UNDER THE INTERSTATE COMMERCE ACT OIL PIPELINE DEPRECIATION STUDIES § 347.1 Material to support request for newly established or changed property account depreciation studies. (a) Means of...

  15. Long Range Materials Research. Appendix 1. Synthesis and Characterization of Supported Organometallic Rhodium (I) Catalysts

    DTIC Science & Technology

    1974-06-30

    support organo - metallic homogeneous catalysts on inert supports. This thesis describes the synthesis of a new chelating ligand for binding...homogeneous catalysts to silica surfaces, a now method using poisons for distinguishing con- ventional heterogeneous catal’,sts from the newer supported organo ...Homogeneous HIydrogenation by Rhodium(l) Complexes Homogeneous catalysts have both served and plagued alchemists and chemists since work began with solutions

  16. Laser and electron-beam powder-bed additive manufacturing of metallic implants: A review on processes, materials and designs.

    PubMed

    Sing, Swee Leong; An, Jia; Yeong, Wai Yee; Wiria, Florencia Edith

    2016-03-01

    Additive manufacturing (AM), also commonly known as 3D printing, allows the direct fabrication of functional parts with complex shapes from digital models. In this review, the current progress of two AM processes suitable for metallic orthopaedic implant applications, namely selective laser melting (SLM) and electron beam melting (EBM) are presented. Several critical design factors such as the need for data acquisition for patient-specific design, design dependent porosity for osteo-inductive implants, surface topology of the implants and design for reduction of stress-shielding in implants are discussed. Additive manufactured biomaterials such as 316L stainless steel, titanium-6aluminium-4vanadium (Ti6Al4V) and cobalt-chromium (CoCr) are highlighted. Limitations and future potential of such technologies are also explored.

  17. Heat treatment and the use of additives to improve the stability of paralytic shellfish poisoning toxins in shellfish tissue reference materials for internal quality control and proficiency testing.

    PubMed

    Burrell, Stephen; Clion, Valentin; Auroy, Virginie; Foley, Barry; Turner, Andrew D

    2015-06-01

    The need for homogenous reference materials stable for paralytic shellfish toxins is vital for the monitoring and quality assurance of these potent neurotoxins in shellfish. Two stabilisation techniques were investigated, heat treatment through autoclaving and the addition of preserving additives into the tissue matrix. Short and long-term stability experiments as well as homogeneity determination were conducted on materials prepared by both techniques in comparison with an untreated control using two LC-FLD methods. Both techniques improved the stability of the matrix and the PSP toxins present compared to the controls. A material was prepared using the combined techniques of heat treatment followed by spiking with additives and data is presented from this optimised reference material as used over a two year period in the Irish national monitoring program and in a development exercise as part of a proficiency testing scheme operated by QUASIMEME (Quality Assurance of Information for Marine Environmental Monitoring in Europe) since 2011. The results were indicative of the long-term stability of the material as evidenced through consistent assigned values in the case of the proficiency testing scheme and a low relative standard deviation of 10.5% for total toxicity data generated over 24 months.

  18. Evaluation of western shale-oil residue as an additive to petroleum asphalt for use as a pavement crack and joint sealant material

    SciTech Connect

    Harnsberger, P.M.; Wolf, J.M.; Robertson, R.E.

    1992-11-01

    The objective of this study was to perform a preliminary evaluation of using a distillation residue from Green River Formation (western) shale oil as an additive to a petroleum asphalt for use as a crack and joint filler material in portland cement concrete and asphaltic pavements. A commercially available rubberized asphalt crack and joint filler material was also tested for comparison. ASTM specification tests for sealant materials used in concrete and asphalt pavements were performed on the sealant materials. Portland cement concrete briquets prepared with an asphalt material sandwiched between two concrete wafers were tested in a stress-relaxation experiment to evaluate the relaxation and recovery properties of the sealant materials. The results show that the shale-oil modified petroleum asphalts and the neat petroleum asphalt do not pass the extension portion of the ASTM test; however, there is indication of improvement in the adhesive properties of the shale-oil modified asphalts. There is also evidence that the addition of shale-oil residue to the petroleum asphalt, especially at the 20% level, improves the relaxation and recovery properties compared with the petroleum asphalt.

  19. Supporting Vocabulary Teaching and Learning in Prekindergarten: The Role of Educative Curriculum Materials

    ERIC Educational Resources Information Center

    Neuman, Susan B.; Pinkham, Ashley; Kaefer, Tanya

    2015-01-01

    The purpose of this study was to support teachers' child-directed language and student outcomes by enhancing the educative features of an intervention targeted to vocabulary, conceptual development and comprehension. Using a set of design heuristics (Davis & Krajcik, 2005), our goal was to support teachers' professional development within the…

  20. Social support, material circumstance and health behaviour: influences on health in First Nation and Inuit communities of Canada.

    PubMed

    Richmond, Chantelle A M; Ross, Nancy A

    2008-11-01

    An expansive literature describes the links between social support and health. Though the bulk of this evidence emphasizes the health-enhancing effect of social support, certain aspects can have negative consequences for health (e.g., social obligations). In the Canadian context, the geographically small and socially interconnected nature of First Nation and Inuit communities provides a unique example through which to explore this relationship. Despite reportedly high levels of social support, many First Nation and Inuit communities endure broad social problems, thereby leading us to question the assumption that social support is primarily health protective. We draw from narrative analysis of interviews with 26 First Nation and Inuit Community Health Representatives to critically examine the health and social support relationship, and the social structures through which social support influences health. Findings indicate that there are health-enhancing and health-damaging properties of the health-social support relationship, and that the negative dimensions can significantly outweigh the positive ones. Social support operates at different structural levels, beginning with the individual and extending toward family and community. These social structures are important as they reinforce an individual's sense of belonging, however, these high-density networks can also exert conformity pressures and social obligations that promote health-damaging behaviours such as domestic violence and smoking. The poor material circumstances that characterize so many First Nation and Inuit communities add another layer of complexity as limited resources can trap individuals within the confines of their immediate social contexts. Research and policy interventions must pay close attention to the social context within which social support, health behaviours and material circumstances interact to influence health outcomes among First Nation and Inuit communities.

  1. Utilization of liquid human wastes and introduction into the material cycling in biological life-support systems

    NASA Astrophysics Data System (ADS)

    Kovaleva, N. P.>; Ushakova, S. A.; Gribovskaya, I. V.; Kudenko, U. A.

    The possibilities of step-by-step utilization of liquid human wastes in biological life-support systems on long-functioning space stations have been considered in this work. Utilization involves "wet" urine incineration with hydrogen peroxide at normal pressure and 90 - 95°C temperature, urease-enzymic decomposition of urine and biological desalination in the higher plant link. The soybean flour was used as a source of urease. Growing soya plants as a component of the higher plant link would give a steady source of urease to the system. To decompose urea (9-15g) contained in 1l of incinerated urine we used 0.5 - 1 g of soy flour. The duration of hydrolysis of daily urea excreted by a human is 70 - 95 hours. It is supposed that ammonia excreted in the reaction of urea decomposition will be processed by nitrifying bacteria. The concentration of total nitrogen in urine after urea hydrolysis and removal of ammonia formed during the reaction constituted 0.6 - 1.2 g/l. Further biological desalination was carried out in the higher plant link, for that the edible salt-accumulating halophytes Salicornia europaea were used. To grow this plant under the aqueous culture conditions, the urine was additionally mineralized at 180 °C after incineration and decomposition of urea. The process of additional mineralization was related to the necessity of removal of organic materials and nitrogen residues, which higher concentration under the aqueous culture conditions has negative effect on plants. The volume of the nutrient solution for growing 6 plants of Salicornia europaea was 1.5 l (daily norm of urine excreted by human), the planting area was 0.032 m2. By the end of vegetation the productivity and mineral composition of Salicornia europaea plants were analyzed. The productivity of plants grown on liquid human wastes (the experiment) practically was not different from the productivity of plants grown on the mineral solution with sodium chloride (checkout). In experimental

  2. Reusable biocompatible interface for immobilization of materials on a solid support

    DOEpatents

    Salamon, Zdzislaw; Schmidt, Richard A.; Tollin, Gordon; Macleod, H. Angus

    1996-01-01

    A method for the formation of a biocompatible film composed of a self-assembled bilayer membrane deposited on a planar surface. This bilayer membrane is capable of immobilizing materials to be analyzed in an environment very similar to their native state. Materials so immobilized may be subject to any of a number of analytical techniques.

  3. Student-Instructor Communication: An Innovative Teaching Material in Support of Student Learning

    ERIC Educational Resources Information Center

    Cheng, Kai- Wen; Chen, Yu-Fen

    2008-01-01

    The purpose of this study was to understand how the innovative teaching material "Interactive Learning Disk (ILD)" could enhance the learning effect of students taking the course of Tourist Database Management (TDM). "ILD" is a kind of teaching material that incorporate interactive concept into course and help students to learn after class. This…

  4. Reusable biocompatible interface for immobilization of materials on a solid support

    DOEpatents

    Salamon, Z.; Schmidt, R.A.; Tollin, G.; Macleod, H.A.

    1996-05-28

    A method is presented for the formation of a biocompatible film composed of a self-assembled bilayer membrane deposited on a planar surface. This bilayer membrane is capable of immobilizing materials to be analyzed in an environment very similar to their native state. Materials so immobilized may be subject to any of a number of analytical techniques. 3 figs.

  5. Development of a Support Environment for First Year Students Taking Materials Science/Engineering

    ERIC Educational Resources Information Center

    Laoui, Tahar; O'Donoghue, John

    2008-01-01

    This paper is based on the experience acquired in teaching materials science/engineering to first year university students. It has been observed that students struggle with some of the fundamental materials concepts addressed in the module/course. This applies to delivered lectures but extends to the incorporation of tutorial sessions provided…

  6. Distinguished-Level Learning Online: Support Materials from LangNet and RussNet

    ERIC Educational Resources Information Center

    Leaver, Betty Lou; Ehrman, Madeline; Lekic, Maria

    2004-01-01

    This article introduces the reader to two online sources of materials for working on improving listening and reading skills. The materials are intended for learners already at Interagency Language Roundtable (ILR) Level 3 (Superior) proficiency in Arabic, Chinese, Hindi, Korean, Russian, and Spanish, who desire to reach Level 4 (Distinguished, or…

  7. Investigation of cross-linked and additive containing polymer materials for membranes with improved performance in pervaporation and gas separation.

    PubMed

    Hunger, Katharina; Schmeling, Nadine; Jeazet, Harold B Tanh; Janiak, Christoph; Staudt, Claudia; Kleinermanns, Karl

    2012-10-22

    Pervaporation and gas separation performances of polymer membranes can be improved by crosslinking or addition of metal-organic frameworks (MOFs). Crosslinked copolyimide membranes show higher plasticization resistance and no significant loss in selectivity compared to non-crosslinked membranes when exposed to mixtures of CO2/CH4 or toluene/cyclohexane. Covalently crosslinked membranes reveal better separation performances than ionically crosslinked systems. Covalent interlacing with 3-hydroxypropyldimethylmaleimide as photocrosslinker can be investigated in situ in solution as well as in films, using transient UV/Vis and FTIR spectroscopy. The photocrosslinking yield can be determined from the FTIR-spectra. It is restricted by the stiffness of the copolyimide backbone, which inhibits the photoreaction due to spatial separation of the crosslinker side chains. Mixed-matrix membranes (MMMs) with MOFs as additives (fillers) have increased permeabilities and often also selectivities compared to the pure polymer. Incorporation of MOFs into polysulfone and Matrimid® polymers for MMMs gives defect-free membranes with performances similar to the best polymer membranes for gas mixtures, such as O2/N2 H2/CH4, CO2/CH4, H2/CO2, CH4/N2 and CO2/N2 (preferentially permeating gas is named first). The MOF porosity, its particle size and content in the MMM are factors to influence the permeability and the separation performance of the membranes.

  8. Investigation of Cross-Linked and Additive Containing Polymer Materials for Membranes with Improved Performance in Pervaporation and Gas Separation

    PubMed Central

    Hunger, Katharina; Schmeling, Nadine; Jeazet, Harold B. Tanh; Janiak, Christoph; Staudt, Claudia; Kleinermanns, Karl

    2012-01-01

    Pervaporation and gas separation performances of polymer membranes can be improved by crosslinking or addition of metal-organic frameworks (MOFs). Crosslinked copolyimide membranes show higher plasticization resistance and no significant loss in selectivity compared to non-crosslinked membranes when exposed to mixtures of CO2/CH4 or toluene/cyclohexane. Covalently crosslinked membranes reveal better separation performances than ionically crosslinked systems. Covalent interlacing with 3-hydroxypropyldimethylmaleimide as photocrosslinker can be investigated in situ in solution as well as in films, using transient UV/Vis and FTIR spectroscopy. The photocrosslinking yield can be determined from the FTIR-spectra. It is restricted by the stiffness of the copolyimide backbone, which inhibits the photoreaction due to spatial separation of the crosslinker side chains. Mixed-matrix membranes (MMMs) with MOFs as additives (fillers) have increased permeabilities and often also selectivities compared to the pure polymer. Incorporation of MOFs into polysulfone and Matrimid® polymers for MMMs gives defect-free membranes with performances similar to the best polymer membranes for gas mixtures, such as O2/N2 H2/CH4, CO2/CH4, H2/CO2, CH4/N2 and CO2/N2 (preferentially permeating gas is named first). The MOF porosity, its particle size and content in the MMM are factors to influence the permeability and the separation performance of the membranes. PMID:24958427

  9. I. Synthesis, characterization, and base catalysis of novel zeolite supported super-basic materials II. Oxidative dehydrogenation of ethane over reduced heteropolyanion catalysts

    NASA Astrophysics Data System (ADS)

    Galownia, Jonathan M.

    This thesis is composed of two separate and unrelated projects. The first part of this thesis outlines an investigation into the synthesis and characterization of a novel zeolite supported super-base capable of carbon-carbon olefin addition to alkyl aromatics. A zeolite supported basic material capable of such reactions would benefit many fine chemical syntheses, as well as vastly improve the economics associated with production of the high performance thermoplastic polyester polyethylene naphthalate. The thermal decomposition of alkali---metal azides impregnated in zeolite X is investigated as a novel route to the synthesis of a zeolite supported super-base. Impregnation of the alkali---metal azide precursor is shown to result in azide species occluded within the pores of the zeolite support by using high speed, solid-state 23Na MAS and 2D MQMAS NMR, FTIR, and TGA characterization methods. Addition of alkali---metal azides to the zeolite results in redistribution of the extra-lattice cations in the zeolite framework. Thermal decomposition of impregnated azide species produces further cation redistribution, but no neutral metallic clusters are detected by high speed, solid-state 23Na MAS NMR following thermal activation of the materials. Instead, it is possible that inactive ionic clusters are formed. The thermally activated materials do not promote base catalysis for the isomerization of 1-butene, the ethylation of toluene and o-xylene, and the alkenylation of o-xylene with 1,3-butadiene to produce 5-ortho-tolyl-pent-2-ene (5-OTP). The lack of catalytic activity in the materials is attributed to failure of the materials to form neutral metallic clusters during thermal treatment, possibly due to preferential formation of NMR silent ionic clusters. The formation of neutral metallic clusters is found to be insensitive to synthesis technique and activation procedure. It is concluded that the impregnation of alkali---metal azides in zeolite X does not provide a

  10. KCP Activities Supporting the W76LEP Stress Cushions and LK3626 RTV Replacement Material Development

    SciTech Connect

    J. W. Schneider

    2009-10-01

    The S-5370 RTV blown foam previously produced by Dow Corning is no longer commercially available. The S-5370 material has been used on all of Los Alamos National Laboratory (LANL) programs to manufacture Stress Cushions up through the W88. The Kansas City Plant (KCP) did not have a sufficient supply of S-5370 material to cover the schedule requirements for the Program. This report provides information on the numerous activities conducted at KCP involving the development of the Program Stress Cushion and replacement RTV material.

  11. FY 1984 and FY 1985 geochemistry and materials studies in support of the Magma Energy Extraction Program

    SciTech Connect

    Westrich, H.R.; Weirick, L.J.; Cygan, R.T.; Reece, M.; Hlava, P.F.; Stockman, H.W.; Gerlach, T.M.

    1986-04-01

    Geochemistry and materials studies are being performed in support of the Magma Energy Extraction Program. The work is largely restricted to: (1) characterizing magmatic environments at sites of interest, (2) testing engineering materials in laboratory simulated magmatic environments, (3) investigating chemical mass transport effects inherent in designs for direct contact heat exchangers, and (4) evaluating degassing hazards associated with drilling into and extracting energy from shallow magma. Magma characterization studies have been completed for shallow magma at Long Valley, Coso volcanic field, and Kilauea volcano. The behavior of 17 commercially available materials has been examined in rhyolite magma at 850/sup 0/C and 200 MPa for periods up to seven days. Analysis of reaction products from materials tests to date indicate that oxidation is the main corrosion problem for most alloys in rhyolitic magma. Considerations of corrosion resistance, high-temperature strength, and cost indicate nickel-base superalloys offer the most promise as candidates for use in rhyolitic magma.

  12. Mesophilic hydrogen production in acidogenic packed-bed reactors (APBR) using raw sugarcane vinasse as substrate: Influence of support materials.

    PubMed

    Nunes Ferraz Júnior, Antônio Djalma; Etchebehere, Claudia; Zaiat, Marcelo

    2015-08-01

    Bio-hydrogen production from sugarcane vinasse in anaerobic up-flow packed-bed reactors (APBR) was evaluated. Four types of support materials, expanded clay (EC), charcoal (Ch), porous ceramic (PC), and low-density polyethylene (LDP) were tested as support for biomass attachment. APBR (working volume - 2.3 L) were operated in parallel at a hydraulic retention time of 24 h, an organic loading rate of 36.2 kg-COD m(-3) d(-1), at 25 °C. Maximum volumetric hydrogen production values of 509.5, 404, 81.4 and 10.3 mL-H2 d(-1) L(-1)reactor and maximum yields of 3.2, 2.6, 0.4 and 0.05 mol-H2 mol(-1) carbohydrates total, were observed during the monitoring of the reactors filled with LDP, EC, Ch and PC, respectively. Thus, indicating the strong influence of the support material on H2 production. LDP was the most appropriate material for hydrogen production among the materials evaluated. 16S rRNA gene by Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis and scanning electron microscopy confirmed the selection of different microbial populations. 454-pyrosequencing performed on samples from APBR filled with LDP revealed the presence of hydrogen-producing organisms (Clostridium and Pectinatus), lactic acid bacteria and non-fermentative organisms.

  13. Biodegradation or simple adsorption to the support material? Development of a simple, fast and low-cost technique.

    PubMed

    Maurício, R; Amaral, L; Santos Coelho, P; Santana, F

    2013-12-01

    Biofilms are present in several areas and are studied in microbiology, medical sciences, biology and, of course, sanitary engineering. Biofilms are used for the treatment of municipal wastewater, and their application was even before the invention of the activated sludge process. The main objective of this work was to develop a simple, fast and low-cost technique to evaluate the nature of the first decay in the concentration of an organic compound in the presence of a solid material. Though simple, the technique developed has allowed the clarification of whether the initial concentration decay is due to adsorption to the support material or a result of biodegradation. The results show that, with two different support materials, adsorption does not take place, and the biodegradation processes are responsible for the first decay in the organic concentration. The technique used offers a fast and low-cost way of studying the existence of adsorption. Two feed concentration solutions and two different support materials were used.

  14. Superconductive material and magnetic field for damping and levitation support and damping of cryogenic instruments

    NASA Technical Reports Server (NTRS)

    Dolgin, Benjamin P. (Inventor)

    1994-01-01

    A superconductive load bearing support without a mechanical contact and vibration damping for cryogenic instruments in space is presented. The levitation support and vibration damping is accomplished by the use of superconducting magnets and the 'Meissner' effect. The assembly allows for transfer of vibration energy away from the cryogenic instrument which then can be damped by the use of either an electronic circuit or conventional vibration damping mean.

  15. Conversion of biomass-derived sorbitol to glycols over carbon-materials supported Ru-based catalysts

    PubMed Central

    Guo, Xingcui; Guan, Jing; Li, Bin; Wang, Xicheng; Mu, Xindong; Liu, Huizhou

    2015-01-01

    Ruthenium (Ru) supported on activated carbon (AC) and carbon nanotubes (CNTs) was carried out in the hydrogenolysis of sorbitol to ethylene glycol (EG) and 1,2-propanediol (1,2-PD) under the promotion of tungsten (WOx) species and different bases. Their catalytic activities and glycols selectivities strongly depended on the support properties and location of Ru on CNTs, owning to the altered metal-support interactions and electronic state of ruthenium. Ru located outside of the tubes showed excellent catalytic performance than those encapsulated inside the nanotubes. Additionally, the introduction of WOx into Ru/CNTs significantly improved the hydrogenolysis activities, and a complete conversion of sorbitol with up to 60.2% 1,2-PD and EG yields was obtained on RuWOx/CNTs catalyst upon addition of Ca(OH)2. Stability study showed that this catalyst was highly stable against leaching and poisoning and could be recycled several times. PMID:26578426

  16. Conversion of biomass-derived sorbitol to glycols over carbon-materials supported Ru-based catalysts

    NASA Astrophysics Data System (ADS)

    Guo, Xingcui; Guan, Jing; Li, Bin; Wang, Xicheng; Mu, Xindong; Liu, Huizhou

    2015-11-01

    Ruthenium (Ru) supported on activated carbon (AC) and carbon nanotubes (CNTs) was carried out in the hydrogenolysis of sorbitol to ethylene glycol (EG) and 1,2-propanediol (1,2-PD) under the promotion of tungsten (WOx) species and different bases. Their catalytic activities and glycols selectivities strongly depended on the support properties and location of Ru on CNTs, owning to the altered metal-support interactions and electronic state of ruthenium. Ru located outside of the tubes showed excellent catalytic performance than those encapsulated inside the nanotubes. Additionally, the introduction of WOx into Ru/CNTs significantly improved the hydrogenolysis activities, and a complete conversion of sorbitol with up to 60.2% 1,2-PD and EG yields was obtained on RuWOx/CNTs catalyst upon addition of Ca(OH)2. Stability study showed that this catalyst was highly stable against leaching and poisoning and could be recycled several times.

  17. Investigating the role of educative curriculum materials in supporting teacher enactment of a field-based urban ecology investigation

    NASA Astrophysics Data System (ADS)

    Houle, Meredith

    2008-10-01

    This multiple case study examined how three urban science teachers used curriculum materials designed educatively. Educative curriculum materials have been suggested as one way to support science teacher learning, particularly around new innovations and new pedagogies and to support teachers in evaluating and modifying materials to meet the needs of their students (Davis & Krajcik, 2005). While not a substitute for professional development, educative curriculum materials may provide an opportunity to support teachers' enactment and learning in the classroom context (Davis & Krajcik, 2005; Remillard, 2005; Schneider & Krajcik, 2002). However, little work has examined how science teachers interact with written curriculum materials to design classroom instruction. Grounded in sociocultural analysis, this study takes the theoretical stance that teachers and curriculum materials are engaged in a dynamic and participatory relationship from which the planned and enacted curriculum emerges (Remillard, 2005). Teaching is therefore a design activity where teachers rely on their personal resources and the curricular resources to construct and shape their students' learning experiences (Brown, 2002). Specifically this study examines how teacher beliefs influence their reading and use of curriculum and how educative features in the written curriculum inform teachers' pedagogical decisions. Data sources included classroom observation and video, teacher interviews, and classroom artifacts. To make sense how teachers' make curricular decisions, video were analyzed using Brown's (2002) Pedagogical Design for Enactment Framework. These coded units were examined in light of the teacher interviews, classroom notes and artifacts to examine how teachers' beliefs influenced these decisions. Data sources were then reexamined for evidence of teachers' use of specific educative features. My analyses revealed that teachers' beliefs about curriculum influenced the degree to which teachers

  18. Estimation of Curie temperature of manganite-based materials for magnetic refrigeration application using hybrid gravitational based support vector regression

    NASA Astrophysics Data System (ADS)

    Owolabi, Taoreed O.; Akande, Kabiru O.; Olatunji, Sunday O.; Alqahtani, Abdullah; Aldhafferi, Nahier

    2016-10-01

    Magnetic refrigeration (MR) technology stands a good chance of replacing the conventional gas compression system (CGCS) of refrigeration due to its unique features such as high efficiency, low cost as well as being environmental friendly. Its operation involves the use of magnetocaloric effect (MCE) of a magnetic material caused by application of magnetic field. Manganite-based material demonstrates maximum MCE at its magnetic ordering temperature known as Curie temperature (TC). Consequently, manganite-based material with TC around room temperature is essentially desired for effective utilization of this technology. The TC of manganite-based materials can be adequately altered to a desired value through doping with appropriate foreign materials. In order to determine a manganite with TC around room temperature and to circumvent experimental challenges therein, this work proposes a model that can effectively estimates the TC of manganite-based material doped with different materials with the aid of support vector regression (SVR) hybridized with gravitational search algorithm (GSA). Implementation of GSA algorithm ensures optimum selection of SVR hyper-parameters for improved performance of the developed model using lattice distortions as the descriptors. The result of the developed model is promising and agrees excellently with the experimental results. The outstanding estimates of the proposed model suggest its potential in promoting room temperature magnetic refrigeration through quick estimation of the effect of dopants on TC so as to obtain manganite that works well around the room temperature.

  19. Biaxial experiments supporting the development of constitutive theories for advanced high-temperature materials

    NASA Technical Reports Server (NTRS)

    Ellis, J. R.

    1988-01-01

    Complex states of stress and strain are introduced into components during service in engineering applications. It follows that analysis of such components requires material descriptions, or constitutive theories, which reflect the tensorial nature of stress and strain. For applications involving stress levels above yield, the situation is more complex in that material response is both nonlinear and history dependent. This has led to the development of viscoplastic constitutive theories which introduce time by expressing the flow and evolutionary equation in the form of time derivatives. Models were developed here which can be used to analyze high temperature components manufactured from advanced composite materials. In parallel with these studies, effort was directed at developing multiaxial testing techniques to verify the various theories. Recent progress in the development of constitutive theories from both the theoretical and experimental viewpoints are outlined. One important aspect is that material descriptions for advanced composite materials which can be implemented in general purpose finite element codes and used for practical design are verified.

  20. Ozonation of bezafibrate over ceria and ceria supported on carbon materials.

    PubMed

    Gonçalves, Alexandra G; Órfão, José J M; Pereira, Manuel Fernando R

    2015-01-01

    Two catalysts containing ceria dispersed on the surface of multi-walled carbon nanotubes and activated carbon were investigated as ozonation catalysts for the mineralization of bezafibrate (BZF). The results were compared with those obtained in the absence of the catalyst and in the presence of the parent carbon materials, as well as in the presence of ceria (CeO2). Carbon materials containing ceria showed an interesting catalytic effect. Both materials enhanced the mineralization of BZF relatively to single ozonation and ozonation catalysed by the corresponding carbon materials. In the catalytic ozonation with these materials, both surface and bulk reactions are supposed to occur. The BZF ozonation catalysed by CeO2 leaded to the highest mineralization degrees, indicating that the reaction mechanism followed in the presence of CeO2 (free radical oxidation in solution) leads to the formation of intermediates more easily degradable, mainly after 120 min of reaction. Some primary products and refractory final oxidation compounds in single and catalytic ozonation of BZF were followed. The original chlorine present on the BZF molecule is completely converted to chloride anion and part of the nitrogen is mainly converted to NO3- along with smaller amounts of NO2- and NH4+. Microtox tests revealed that simultaneous use of ozone and CeO2 originated lower acute toxicity.

  1. REMOTE MATERIAL HANDLING IN THE YUCCA MOUNTAIN WASTE PACKAGE CLOSURE CELL AND SUPPORT AREA GLOVEBOX

    SciTech Connect

    K.M. Croft; S.M. Allen; M.W. Borland

    2005-08-02

    The Yucca Mountain Waste Package Closure System (WPCS) cells provide for shielding of highly radioactive materials contained in unsealed waste packages. The purpose of the cells is to provide safe environments for package handling and sealing operations. Once sealed, the packages are placed in the Yucca Mountain Repository. Closure of a typical waste package involves a number of remote operations. Those involved typically include the placement of matched lids onto the waste package. The lids are then individually sealed to the waste package by welding. Currently, the waste package includes three lids. One lid is placed before movement of the waste package to the closure cell; the final two are placed inside the closure cell, where they are welded to the waste package. These and other important operations require considerable remote material handling within the cell environment. This paper discusses the remote material handling equipment, designs, functions, operations, and maintenance, relative to waste package closure.

  2. A Statistics-Based Material Property Analysis to Support TPS Characterization

    NASA Technical Reports Server (NTRS)

    Copeland, Sean R.; Cozmuta, Ioana; Alonso, Juan J.

    2012-01-01

    Accurate characterization of entry capsule heat shield material properties is a critical component in modeling and simulating Thermal Protection System (TPS) response in a prescribed aerothermal environment. The thermal decomposition of the TPS material during the pyrolysis and charring processes is poorly characterized and typically results in large uncertainties in material properties as inputs for ablation models. These material property uncertainties contribute to large design margins on flight systems and cloud re- construction efforts for data collected during flight and ground testing, making revision to existing models for entry systems more challenging. The analysis presented in this work quantifies how material property uncertainties propagate through an ablation model and guides an experimental test regimen aimed at reducing these uncertainties and characterizing the dependencies between properties in the virgin and charred states for a Phenolic Impregnated Carbon Ablator (PICA) based TPS. A sensitivity analysis identifies how the high-fidelity model behaves in the expected flight environment, while a Monte Carlo based uncertainty propagation strategy is used to quantify the expected spread in the in-depth temperature response of the TPS. An examination of how perturbations to the input probability density functions affect output temperature statistics is accomplished using a Kriging response surface of the high-fidelity model. Simulations are based on capsule configuration and aerothermal environments expected during the Mars Science Laboratory (MSL) entry sequence. We identify and rank primary sources of uncertainty from material properties in a flight-relevant environment, show the dependence on spatial orientation and in-depth location on those uncertainty contributors, and quantify how sensitive the expected results are.

  3. Preparation of layered double hydroxides and their applications as additives in polymers, as precursors to magnetic materials and in biology and medicine.

    PubMed

    Evans, David G; Duan, Xue

    2006-02-07

    In recent years layered double hydroxides (LDHs), also known as hydrotalcite-like materials, have attracted considerable interest from both industry and academia. In this article, we discuss methods of preparing LDHs with an emphasis on the way in which particle size and morphology can be controlled with regard to specific target applications; scale-up of one such preparation procedure is also described. In addition, we review selected applications of LDHs developed by our own and other laboratories.

  4. Environmental Support Specialist, Block V, 17-6. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

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

    This military-developed text contains the third section of a four-part course to train environmental support specialists. Covered in the individual sections are field sanitation, classes and sources of waste, composition and characteristics of sewage, principles of sewage treatment, primary waste treatment, secondary waste treatment, tertiary…

  5. APPLICATION OF THE US DECISION SUPPORT TOOL FOR MATERIALS AND WASTE MANAGEMENT

    EPA Science Inventory

    EPA¿s National Risk Management Research Laboratory has led the development of a municipal solid waste decision support tool (MSW-DST). The computer software can be used to calculate life-cycle environmental tradeoffs and full costs of different waste management plans or recycling...

  6. Feasibility of a Supporting-Salt-Free Nonaqueous Redox Flow Battery Utilizing Ionic Active Materials.

    PubMed

    Milshtein, Jarrod D; Fisher, Sydney L; Breault, Tanya M; Thompson, Levi T; Brushett, Fikile R

    2017-02-08

    Nonaqueous redox flow batteries (NAqRFBs) are promising devices for grid-scale energy storage, but high projected prices could limit commercial prospects. One route to reduced prices is to minimize or eliminate the expensive supporting salts typically employed in NAqRFBs. Herein, the feasibility of a flow cell operating in the absence of supporting salt by utilizing ionic active species is demonstrated. These ionic species have high conductivities in acetonitrile (12-19 mS cm(-1) ) and cycle at 20 mA cm(-2) with energy efficiencies (>75 %) comparable to those of state-of-the-art NAqRFBs employing high concentrations of supporting salt. A chemistry-agnostic techno-economic analysis highlights the possible cost savings of minimizing salt content in a NAqRFB. This work offers the first demonstration of a NAqRFB operating without supporting salt. The associated design principles can guide the development of future active species and could make NAqRFBs competitive with their aqueous counterparts.

  7. TV Spots and Supportive Printed Materials on Child-Rearing Practices. Work Unit III. Final Report.

    ERIC Educational Resources Information Center

    Southwest Educational Development Lab., Austin, TX.

    This is the 1976-1977 final report of Work Unit III of Southwest Educational Development Laboratory's Early Childhood Program. The Unit was funded to develop media products, mass media delivery strategies, television spot announcements and supportive booklets designed to increase awareness of certain child-rearing skills and practices among low…

  8. Transforming Middle School Geometry: Designing Professional Development Materials that Support the Teaching and Learning of Similarity

    ERIC Educational Resources Information Center

    Seago, Nanette; Jacobs, Jennifer; Driscoll, Mark

    2010-01-01

    Although there are increasing numbers of professional development (PD) materials intended to foster teachers' mathematical knowledge for teaching within the topics of number and algebra, little attention has been given to geometry. In this article we describe the Learning and Teaching Geometry project's approach to the development of PD materials…

  9. Covalent attachment of lysozyme to cotton/cellulose materials: protein verses solid support activation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Covalent attachment of enzymes to cellulosic materials like cotton is of interest where either release or loss of enzyme activity over time needs to be avoided. The covalent attachment of an enzyme to a cellulosic substrate requires either activation of a protein side chain or an organic functional ...

  10. The Efficacy of Educative Curriculum Materials to Support Geospatial Science Pedagogical Content Knowledge

    ERIC Educational Resources Information Center

    Bodzin, Alec; Peffer, Tamara; Kulo, Violet

    2012-01-01

    Teaching and learning about geospatial aspects of energy resource issues requires that science teachers apply effective science pedagogical approaches to implement geospatial technologies into classroom instruction. To address this need, we designed educative curriculum materials as an integral part of a comprehensive middle school energy…

  11. Investigation of Nitrogen-Rich Carbon Nitride Networks as Redox-Active Metal Catalyst Support Materials

    DTIC Science & Technology

    2004-10-29

    Equation 1),1 although for mass balance there may be trace amounts of chloramines or chlorine gas also produced. (C3N3)(NHCl)3 C3N4+x(H)y + (3-y...It is significant to realize that the carbon nitride (C3N4+x) materials are formed under very hot and corrosive acidic conditions, facts that bode

  12. Using Japanese Curriculum Materials to Support Lesson Study outside Japan: Toward Coherent Curriculum

    ERIC Educational Resources Information Center

    Lewis, Catherine C.; Perry, Rebecca R.; Friedkin, Shelley

    2011-01-01

    Lesson study (jugyou kenkyuu) has spread outside Japan in the last decade, providing opportunities to see how lesson study fares in countries where the instructional practices and curriculum materials differ from those in Japan. This study reports an elementary mathematics lesson study cycle from the United States. To investigate the nature of the…

  13. Satellite Material Type and Phase Function Determination in Support of Orbital Debris Size Estimation

    NASA Technical Reports Server (NTRS)

    Hejduk, M. D.; Cowardin, H. M.; Stansbery, Eugene G.

    2012-01-01

    In performing debris surveys of deep-space orbital regions, the considerable volume of the area to be surveyed and the increased orbital altitude suggest optical telescopes as the most efficient survey instruments; but to proceed this way, methodologies for debris object size estimation using only optical tracking and photometric information are needed. Basic photometry theory indicates that size estimation should be possible if satellite albedo and shape are known. One method for estimating albedo is to try to determine the object's material type photometrically, as one can determine the albedos of common satellite materials in the laboratory. Examination of laboratory filter photometry (using Johnson BVRI filters) on a set of satellite material samples indicates that most material types can be separated at the 1-sigma level via B-R versus R-I color differences with a relatively small amount of required resampling, and objects that remain ambiguous can be resolved by B-R versus B-V color differences and solar radiation pressure differences. To estimate shape, a technique advanced by Hall et al. [1], based on phase-brightness density curves and not requiring any a priori knowledge of attitude, has been modified slightly to try to make it more resistant to the specular characteristics of different materials and to reduce the number of samples necessary to make robust shape determinations. Working from a gallery of idealized debris shapes, the modified technique identifies most shapes within this gallery correctly, also with a relatively small amount of resampling. These results are, of course, based on relatively small laboratory investigations and simulated data, and expanded laboratory experimentation and further investigation with in situ survey measurements will be required in order to assess their actual efficacy under survey conditions; but these techniques show sufficient promise to justify this next level of analysis.

  14. New Synthesis of Mo 2C 14 nm in Average Size Supported on a High Specific Surface Area Carbon Material

    NASA Astrophysics Data System (ADS)

    Mordenti, Delphine; Brodzki, Dominique; Djéga-Mariadassou, Gérald

    1998-11-01

    A molybdenum carbide supported on active carbon for catalytic hydrotreating was prepared by temperature-programmed reaction (TPR) in flowing H2of an active carbon impregnated by an heptamolybdate. TPR led at 973 K to the formation of supported Mo2C. This new method of preparation avoids the use of methane as carburizing reactant and allowsin situpreparation of supported molybdenum carbide without any contact of this pyrrophoric material with air between preparation and catalytic run. The various steps of the carburization process were studied by trapping the solid intermediates at different temperatures during TPR. Two successive reactions were evidenced: the partial reduction by H2of the initial molybdenum precursor to MoO2, and its subsequent carburization to Mo2C. This last step is mainly due to the reduction of MoO2and carburization with native methane evolved from the reaction of the carbon support with dihydrogen. Solid materials were characterized by elemental analysis, X-Ray diffraction, transmission electron microscopy and specific surface area measurements.

  15. Degradation of simazine from aqueous solutions by diatomite-supported nanosized zero-valent iron composite materials.

    PubMed

    Sun, Zhiming; Zheng, Shuilin; Ayoko, Godwin A; Frost, Ray L; Xi, Yunfei

    2013-12-15

    A novel composite material based on deposition of nanosized zero-valent iron (nZVI) particles on acid-leached diatomite was synthesised for the removal of a chlorinated contaminant in water. The nZVI/diatomite composites were characterised by X-ray diffraction, scanning electron microscopy, elemental analysis, transmission electron microscopy and X-ray photoelectron spectroscopy. Compared with the pure nZVI particles, better dispersion of nZVI particles on the surface or inside the pores of diatom shells was observed. The herbicide simazine was selected as the model chlorinated contaminant and the removal efficiency by nZVI/diatomite composite was compared with that of the pristine nZVI and commercial iron powder. It was found that the diatomite supported nZVI composite material prepared by centrifugation exhibits relatively better efficient activity in decomposition of simazine than commercial Fe, lab synthesised nZVI and composite material prepared via rotary evaporation, and the optimum experimental conditions were obtained based on a series of batch experiments. This study on immobilising nZVI particles onto diatomite opens a new avenue for the practical application of nZVI and the diatomite-supported nanosized zero-valent iron composite materials have potential applications in environmental remediation.

  16. Evaluation of effect of tray space on the accuracy of condensation silicone, addition silicone and polyether impression materials: an in vitro study.

    PubMed

    Kumar, Varun; Aeran, Himanshu

    2012-09-01

    Optimal thickness of impression materials in the custom tray in order to get the most accurate impression. To investigate the effect of different tray spacer thickness on the accuracy and the dimensional stability of impressions made from monophasic condensation silicone, addition silicone and polyether impression materials. Three different types of elastomeric monophasic impression materials were used for making the impression of a master die with tray having tray spacer thickness of 2, 4 and 6 mm. Each type of impression was poured in die stone after 1 h. Each cast was analyzed by a travelling microscope and compared with the master die. The data was tabulated and subjected to statistical evaluation. The results of the study indicated that the impressions made from 2 to 4 mm spaced trays produced more accurate stone casts when compared to 6 mm spaced tray. No statistical significant differences were observed between the accuracy and dimensional stability of the three materials tested. Minimum changes were observed when the cast was poured after 1 h and the tray space was 2 mm for all the materials tested. It is therefore advisable not to exceed tray space of 2 mm.

  17. Enhanced properties of MgO-Al2O3 composite materials with Al powder addition under 1300 °C creep test and its mechanism analysis

    NASA Astrophysics Data System (ADS)

    Jiang, Peng; Ma, Jiajia; Li, Yong; Yue, Dandan; Tong, Shanghao; Xue, Wendong

    2017-04-01

    The Al-MgO-Al2O3 composite samples were prepared with alumina (fused corundum and sintered alumina), high purity sintered magnesia and aluminum powder. Creep test was carried out at 1300 °C and studied. The results show that the creep rate of sample without aluminum addition decreases gradually. The creep properties of the MgO-Al2O3 composite material are improved by aluminum powder addition, with the sample demonstrating an increase creep rate. The physical properties of the samples are enhanced by aluminum powder addition as well. The mechanism of the improvement on the sample is analyzed by different characterization methods and kinetics calculations. Our results indicates that the AlN and MgAl2O4 spinel phases which are formed during the creep test are acting as the reinforcing phases and therefore enhance the creep performance of the samples.

  18. Demonstration of Super Cooled Ice as a Phase Change Material Heat Sink for Portable Life Support Systems

    NASA Technical Reports Server (NTRS)

    Leimkuehler, Thomas O.; Bue, Grant C.

    2009-01-01

    A phase change material (PCM) heat sink using super cooled ice as a nontoxic, nonflammable PCM is being developed. The latent heat of fusion for water is approximately 70% larger than most paraffin waxes, which can provide significant mass savings. Further mass reduction is accomplished by super cooling the ice significantly below its freezing temperature for additional sensible heat storage. Expansion and contraction of the water as it freezes and melts is accommodated with the use of flexible bag and foam materials. A demonstrator unit has been designed, built, and tested to demonstrate proof of concept. Both testing and modeling results are presented along with recommendations for further development of this technology.

  19. Flammability, Odor, and Offgassing Requirements and Test Procedures for Materials in Environments That Support Combustion

    DTIC Science & Technology

    1988-05-01

    Environmental Control and Life Support System FAA Federal Aviation Administration FAR Federal Aviation Regulation FEP Fluorinated Ethylene Propylene GFE...propanol) cyclohexanol ethyl alcohol (ethanol) ethylene glycol (1,2-ethanedioT) 2-hexyl alcohol (2-hexanol) methyl alcohol (methanol) octyl...trichloromethane) 119.4 o-dichlorobenzene (1,2-dichlorobenzene) 147.0 ethyl chloride (chloroethane) 64.50 ethylene chloride (1,2-dichloroethane

  20. Training Materials and Data Requirements for Combat Training Theater (CTT) Training Test Support Plan

    DTIC Science & Technology

    1980-12-01

    NUMBER() James H. Harris (HumRRO) David W. Bessemer (ARI) MDA 903-80-C-0223 Kevin J. McAleese (Honeywell, Inc.)______________ 9. PERFORMING ORGANIZATION...SUPPLEMENTARY NOTES Prepared with conceptual contributions from Dr. D.W. Bessemer , ARI Field Unit, Fort Knox. IS. KEY WORDS (Continue on tevocee side it...TRAINING TEST SUPPORT PLAN James H. Harris Human Resources Research Organization (HumRRO) David W. Bessemer U.S. Army Research Institute for the

  1. Dredging Operations Technical Support Program. Mathematical Model of the Consolidation/Desiccation Processes in Dredged Material.

    DTIC Science & Technology

    1985-07-01

    W. Cargill Geotechnical Laboratory DEPARTMENT OF THE ARMY Waterways Experiment Station, Corps of Engineers PO Box 631 Vicksburg, Mississippi 39180... Engineer Waterways Experiment Station Dredging Operations Geotechnical Laboratory PO Box 631, Vicksburg, Mississippi 39180-0631 Technical Support...improve the mainly empirical methods used in the past for containment area design. This report focuses on one of the primary factors in a well- engineered

  2. Highly Efficient Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol over Gold Supported on Zinc Oxide Materials

    SciTech Connect

    Chen, Hangning; Cullen, David A.; Larese, J. Z.

    2015-11-30

    We used Au/ZnO catalysts for liquid-phase selective hydrogenation of cinnamaldehyde to cinnamyl alcohol and compared with Au/Fe2O3 catalysts. To investigate the influence of the support on the hydrogenation activity and selectivity, three different Au/ZnO catalysts were synthesized, including Au/rod-tetrapod ZnO, Au/porous ZnO, and Au/ZnO-CP prepared using a coprecipitation method. Moreover, the influence of calcination temperature was also systematically investigated in this study. The characterization of Au/ZnO catalysts was performed using ICP, N2 adsorption/desorption isotherms, X-ray diffraction, scanning transmission electron microscopy, and X-ray photoelectron spectroscopy. Among all the supported Au catalysts prepared in this study, Au/ZnO-CP exhibits both the highest hydrogenation activity and selectivity. Using a 1.5% Au/ZnO-CP catalyst, 100% selectivity could be achieved with 94.9% conversion. Finally, we find that the Au particle (size and shape), the ZnO support (size and surface texture) and the interaction between Au and ZnO are three important parameters for achieving a highly efficient Au/ZnO catalyst.

  3. Highly Efficient Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol over Gold Supported on Zinc Oxide Materials

    DOE PAGES

    Chen, Hangning; Cullen, David A.; Larese, J. Z.

    2015-11-30

    We used Au/ZnO catalysts for liquid-phase selective hydrogenation of cinnamaldehyde to cinnamyl alcohol and compared with Au/Fe2O3 catalysts. To investigate the influence of the support on the hydrogenation activity and selectivity, three different Au/ZnO catalysts were synthesized, including Au/rod-tetrapod ZnO, Au/porous ZnO, and Au/ZnO-CP prepared using a coprecipitation method. Moreover, the influence of calcination temperature was also systematically investigated in this study. The characterization of Au/ZnO catalysts was performed using ICP, N2 adsorption/desorption isotherms, X-ray diffraction, scanning transmission electron microscopy, and X-ray photoelectron spectroscopy. Among all the supported Au catalysts prepared in this study, Au/ZnO-CP exhibits both the highest hydrogenationmore » activity and selectivity. Using a 1.5% Au/ZnO-CP catalyst, 100% selectivity could be achieved with 94.9% conversion. Finally, we find that the Au particle (size and shape), the ZnO support (size and surface texture) and the interaction between Au and ZnO are three important parameters for achieving a highly efficient Au/ZnO catalyst.« less

  4. Graphene oxide supported copper oxide nanoneedles: An efficient hybrid material for removal of toxic azo dyes

    NASA Astrophysics Data System (ADS)

    Rajesh, Rajendiran; Iyer, Sahithya S.; Ezhilan, Jayabal; Kumar, S. Senthil; Venkatesan, Rengarajan

    2016-09-01

    Herein, we report a simple, one step synthesis of hybrid copper oxide nanoneedles on graphene oxide sheets (GO-CuONNs) through sonochemical method. The present method affords a facile mean for controlling effective concentration of the active CuO nanoneedles on the graphene oxide sheets, and also offers the necessary stability to the resulting GO-CuONNs structure for adsorption transformations.Furthermore, this hybrid GO-CuONNs is successfully employed in the removal of a series of hazardous ionic organic dyes namely coomassie brilliant blue, methylene blue, congo red and amidoblack 10B. Through careful investigation of the material, we found that the synergetic effect between CuONNs and GO play a significant role in the adsorption of all the dyes studied. The prepared hybrid material contains both hydrophobic and hydrophilic environment which is expected to enhance the electrostatic interaction between the adsorbent and the dye molecules, consequently favouring the adsorption process.

  5. Dredging Operations Technical Support Program: Guidance for Contracting Biological and Chemical Evaluations of Dredged Material

    DTIC Science & Technology

    1990-09-01

    to allowing disposal of dredged material in waters of the United States. Compli- ance requires the avoidance of "unacceptable adverse effects " to the...costs. This may result in increases in cost- effectiveness , although this varies greatly and cannot be assumed. The private firm, which operates at a...BAA is published annually by the US Army Engineer Waterways Experiment Station (WES) and remains in effect until superseded by the latest edition. The

  6. Very High Temperature Reactor (VHTR) Survey of Materials Research and Development Needs to Support Early Deployment

    SciTech Connect

    Eric Shaber; G. Baccaglini; S. Ball; T. Burchell; B. Corwin; T. Fewell; M. Labar; P. MacDonald; P. Rittenhouse; Russ Vollam; F. Southworth

    2003-01-01

    The VHTR reference concept is a helium-cooled, graphite moderated, thermal neutron spectrum reactor with an outlet temperature of 1000 C or higher. It is expected that the VHTR will be purchased in the future as either an electricity producing plant with a direct cycle gas turbine or a hydrogen producing (or other process heat application) plant. The process heat version of the VHTR will require that an intermediate heat exchanger (IHX) and primary gas circulator be located in an adjoining power conversion vessel. A third VHTR mission - actinide burning - can be accomplished with either the hydrogen-production or gas turbine designs. The first ''demonstration'' VHTR will produce both electricity and hydrogen using the IHX to transfer the heat to either a hydrogen production plant or the gas turbine. The plant size, reactor thermal power, and core configuration will be designed to assure passive decay heat removal without fuel damage during accidents. The fuel cycle will be a once-through very high burnup low-enriched uranium fuel cycle. The purpose of this report is to identify the materials research and development needs for the VHTR. To do this, we focused on the plant design described in Section 2, which is similar to the GT-MHR plant design (850 C core outlet temperature). For system or component designs that present significant material challenges (or far greater expense) there may be some viable design alternatives or options that can reduce development needs or allow use of available (cheaper) materials. Nevertheless, we were not able to assess those alternatives in the time allotted for this report and, to move forward with this material research and development assessment, the authors of this report felt that it was necessary to use a GT-MHR type design as the baseline design.

  7. Effect of Ti/Al ratio and Cr, Nb, and Hf additions on material factors and mechanical properties in TiAl

    NASA Astrophysics Data System (ADS)

    Kawabata, T.; Tamura, T.; Izumi, O.

    1993-01-01

    The effect of the Ti/Al ratio and Cr, Nb, and Hf additions on material factors, such as the grain size, second phase, la tice parameters and the axial ratio, and on mechanical properties in TiAl-base alloys has been studied. The grain size was decreased by the deviation from the stoichiometric composition o the Ti-rich side and the addition of the third elements. The Cr element was contained a little more in Ti3Al phase than in TiAl phase in two-phase Ti-rich alloys. The lattice parameters, a and c, and the axial ratio, c/a, of the binary alloys varied linearly with decreasing Al content even in the dual-phase region. The Cr addition decreased the a and c and also c/a. The Nb addition increased weakly the a and c and c/a. On the contrary, the Hf addition increased the a and c but decreased the c/a ratio. In the Cr added alloys, the decrease of volume of a unit cell, due to the substitution of Cr atoms for Ti and Al atoms, was larger than that expected from the difference of atom sizes. The Nb addition should decrease the volume of a unit cell, but it increased the volume. The Hf addition caused a larger increase of volume of a unit cell than that expected from the difference of atom sizes. We suggested that the Cr addition increases and the Nb and Hf additions decrease the bond strength in TiAl. The deviation from stoichiometry and the addition of third elements caused an increase of work-hardening rate. The alloys with Ti-rich composition have superior mechanical properties compared to those of alloys vith Al-rich composition. The Cr addition resulted in high solution hardening, and the Ti-47A1 3Cr (in atomic percent) alloys had the highest fracture strain of 2.7 pct in all alloys tested. The Nb addition resulted in poor ductility in both Ti- and Al-rich alloys. The Hf additions to the Ti-rich composition caused better mechanical properties than those of Al-rich alloys. Thi; trend was also similar to the Nb-added alloys. In the Hf-added alloys, the Ti-49Al-2Hf

  8. Yolk-shell gold nanoparticles as model materials for support-effect studies in heterogeneous catalysis: Au, @C and Au, @ZrO2 for CO oxidation as an example.

    PubMed

    Galeano, Carolina; Güttel, Robert; Paul, Michael; Arnal, Pablo; Lu, An-Hui; Schüth, Ferdi

    2011-07-18

    The use of nanostructured yolk-shell materials offers a way to discriminate support and particle-size effects for mechanistic studies in heterogeneous catalysis. Herein, gold yolk-shell materials have been synthesized and used as model catalysts for the investigation of support effects in CO oxidation. Carbon has been selected as catalytically inert support to study the intrinsic activity of the gold nanoparticles, and for comparison, zirconia has been used as oxidic support. Au, @C materials have been synthesized through nanocasting using two different nonporous-core@mesoporous-shell exotemplates: Au@SiO(2)@ZrO(2) and Au@SiO(2)@m-SiO(2). The catalytic activity of Au, @C with a gold core of about 14 nm has been evaluated and compared with Au, @ZrO(2) of the same gold core size. The strong positive effect of metal oxide as support material on the activity of gold has been proved. Additionally, size effects were investigated using carbon as support to determine only the contribution of the nanoparticle size on the catalytic activity of gold. Therefore, Au, @C with a gold core of about 7 nm was studied showing a less pronounced positive effect on the activity than the metal oxide support effect.

  9. An evaluation of dimensional accuracy of one-step and two-step impression technique using addition silicone impression material: an in vitro study.

    PubMed

    Pande, Neelam A; Parkhedkar, R D

    2013-09-01

    The study is aimed to evaluate the dimensional accuracy, the effect of undercut of two different configurations and the elastic recovery of addition silicone impression material assessed indirectly, by measuring the dimensions on stone models recorded from the impression of the master model, using one-step and two-step impression technique, for addition silicone impression materials. Measurements are taken to evaluate horizontal or linear and vertical dimensional changes, of the abutment V and abutment C from the stainless steel model. Heavy body/light body material is used for making one-step impression technique in a custom tray. Putty/light body is used for taking two-step technique in a stock metal tray. Improved die stone is used for pouring the impression. The different 11 locations on the dies produced by two different techniques are measured microscopically on image analyzer and compared with those of stainless steel model. Anova test was applied to test the differences of mean values of inter and intra abutment measurements, to calculate p value. Unpaired t test was applied to calculate t value. Results showed less deviation of stone models produced by one-step technique from stainless steel model, whereas the deviation of stone models produced by two-step is comparatively more. (p < 0.01). This difference of deviation is significantly less in one-step as compared to two-step technique. One-step is sufficiently dimensionally accurate than two-step technique in conjunction with addition silicone impression material. They have the best elastic recovery from the two undercut configurations.

  10. SUPPORTING SAFE STORAGE OF PLUTONIUM-BEARING MATERIALS THROUGH SCIENCE, ENGINEERING AND SURVEILLANCE

    SciTech Connect

    Dunn, K.; Chandler, G.; Gardner, C.; Louthan, M.; Mcclard, J.

    2009-11-10

    Reductions in the size of the U. S. nuclear weapons arsenal resulted in the need to store large quantities of plutonium-bearing metals and oxides for prolonged periods of time. To assure that the excess plutonium from the U. S. Department of Energy (DOE) sites was stored in a safe and environmentally friendly manner the plutonium-bearing materials are stabilized and packaged according to well developed criteria published as a DOE Standard. The packaged materials are stored in secure facilities and regular surveillance activities are conducted to assure continuing package integrity. The stabilization, packaging, storage and surveillance requirements were developed through extensive science and engineering activities including those related to: plutonium-environment interactions and container pressurization, corrosion and stress corrosion cracking, plutonium-container material interactions, loss of sealing capability and changes in heat transfer characteristics. This paper summarizes some of those activities and outlines ongoing science and engineering programs that assure continued safe and secure storage of the plutonium-bearing metals and oxides.

  11. Manganese Dioxide Supported on Porous Biomorphic Carbons as Hybrid Materials for Energy Storage Devices.

    PubMed

    Gutierrez-Pardo, Antonio; Lacroix, Bertrand; Martinez-Fernandez, Julian; Ramirez-Rico, Joaquin

    2016-11-16

    A facile and low-cost method has been employed to fabricate MnO2/C hybrid materials for use as binder-free electrodes for supercapacitor applications. Biocarbon monoliths were obtained through pyrolysis of beech wood, replicating the microstructure of the cellulosic precursor, and serve as 3D porous and conductive scaffolds for the direct growth of MnO2 nanosheets by a solution method. Evaluation of the experimental results indicates that a homogeneous and uniform composite material made of a carbon matrix exhibiting ordered hierarchical porosity and MnO2 nanosheets with a layered nanocrystalline structure is obtained. The tuning of the MnO2 content and crystallite size via the concentration of KMnO4 used as impregnation solution allows to obtain composites that exhibit enhanced electrochemical behavior, achieving a capacitance of 592 F g(-1) in electrodes containing 3 wt % MnO2 with an excellent cyclic stability. The electrode materials were characterized before and after electrochemical testing.

  12. Materials

    NASA Technical Reports Server (NTRS)

    Glaessgen, Edward H.; Schoeppner, Gregory A.

    2006-01-01

    NASA Langley Research Center has successfully developed an electron beam freeform fabrication (EBF3) process, a rapid metal deposition process that works efficiently with a variety of weldable alloys. The EBF3 process can be used to build a complex, unitized part in a layer-additive fashion, although the more immediate payoff is for use as a manufacturing process for adding details to components fabricated from simplified castings and forgings or plate products. The EBF3 process produces structural metallic parts with strengths comparable to that of wrought product forms and has been demonstrated on aluminum, titanium, and nickel-based alloys to date. The EBF3 process introduces metal wire feedstock into a molten pool that is created and sustained using a focused electron beam in a vacuum environment. Operation in a vacuum ensures a clean process environment and eliminates the need for a consumable shield gas. Advanced metal manufacturing methods such as EBF3 are being explored for fabrication and repair of aerospace structures, offering potential for improvements in cost, weight, and performance to enhance mission success for aircraft, launch vehicles, and spacecraft. Near-term applications of the EBF3 process are most likely to be implemented for cost reduction and lead time reduction through addition of details onto simplified preforms (casting or forging). This is particularly attractive for components with protruding details that would require a significantly large volume of material to be machined away from an oversized forging, offering significant reductions to the buy-to-fly ratio. Future far-term applications promise improved structural efficiency through reduced weight and improved performance by exploiting the layer-additive nature of the EBF3 process to fabricate tailored unitized structures with functionally graded microstructures and compositions.

  13. Fracture Strength of Three-Unit Implant Supported Fixed Partial Dentures with Excessive Crown Height Fabricated from Different Materials

    PubMed Central

    Nazari, Vahideh; Ghodsi, Safoura; Alikhasi, Marzieh; Shamshiri, Ahmad Reza

    2016-01-01

    Objectives: Fracture strength is an important factor influencing the clinical long-term success of implant-supported prostheses especially in high stress situations like excessive crown height space (CHS). The purpose of this study was to compare the fracture strength of implant-supported fixed partial dentures (FPDs) with excessive crown height, fabricated from three different materials. Materials and Methods: Two implants with corresponding abutments were mounted in a metal model that simulated mandibular second premolar and second molar. Thirty 3-unit frameworks with supportive anatomical design were fabricated using zirconia, nickel-chromium alloy (Ni-Cr), and polyetheretherketone (PEEK) (n=10). After veneering, the CHS was equal to 15mm. Then; samples were axially loaded on the center of pontics until fracture in a universal testing machine at a crosshead speed of 0.5 mm/minute. The failure load data were analyzed by one-way ANOVA and Games-Howell tests at significance level of 0.05. Results: The mean failure loads for zirconia, Ni-Cr and PEEK restorations were 2086±362N, 5591±1200N and 1430±262N, respectively. There were significant differences in the mean failure loads of the three groups (P<0.001). The fracture modes in zirconia, metal ceramic and PEEK restorations were cohesive, mixed and adhesive type, respectively. Conclusions: According to the findings of this study, all implant supported three-unit FPDs fabricated of zirconia, metal ceramic and PEEK materials are capable to withstand bite force (even para-functions) in the molar region with excessive CHS. PMID:28243301

  14. Material grain size characterization method based on energy attenuation coefficient spectrum and support vector regression.

    PubMed

    Li, Min; Zhou, Tong; Song, Yanan

    2016-07-01

    A grain size characterization method based on energy attenuation coefficient spectrum and support vector regression (SVR) is proposed. First, the spectra of the first and second back-wall echoes are cut into several frequency bands to calculate the energy attenuation coefficient spectrum. Second, the frequency band that is sensitive to grain size variation is determined. Finally, a statistical model between the energy attenuation coefficient in the sensitive frequency band and average grain size is established through SVR. Experimental verification is conducted on austenitic stainless steel. The average relative error of the predicted grain size is 5.65%, which is better than that of conventional methods.

  15. Strength Analysis and Process Simulation of Subway Contact Rail Support Bracket of Composite Materials

    NASA Astrophysics Data System (ADS)

    Fedulov, Boris N.; Safonov, Alexander A.; Sergeichev, Ivan V.; Ushakov, Andrey E.; Klenin, Yuri G.; Makarenko, Irina V.

    2016-10-01

    An application of composites for construction of subway brackets is a very effective approach to extend their lifetime. However, this approach involves the necessity to prevent process-induced distortions of the bracket due to thermal deformation and chemical shrinkage. At present study, a process simulation has been carried out to support the design of the production tooling. The simulation was based on the application of viscoelastic model for the resin. Simulation results were verified by comparison with results of manufacturing experiments. To optimize the bracket structure the strength analysis was carried out as well.

  16. Intraparietal regions play a material general role in working memory: evidence supporting an internal attentional role

    PubMed Central

    Killebrew, Kyle; Mruczek, Ryan; Berryhill, Marian E.

    2015-01-01

    Determining the role of intraparietal sulcus (IPS) regions in working memory (WM) remains a topic of considerable interest and lack of clarity. One group of hypotheses, the internal attention view, proposes that the IPS plays a material general role in maintaining information in WM. An alternative viewpoint, the pure storage account, proposes that the IPS in each hemisphere maintains material specific (e.g., left – phonological; right – visuospatial) information. Yet, adjudication between competing theoretical perspectives is complicated by divergent findings from different methodologies and their use of different paradigms, perhaps most notably between functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). For example, fMRI studies typically use full field stimulus presentations and report bilateral IPS activation, whereas EEG studies direct attention to a single hemifield and report a contralateral bias in both hemispheres. Here, we addressed this question by applying a regions-of-interest fMRI approach to elucidate IPS contributions to WM. Importantly, we manipulated stimulus type (verbal, visuospatial) and the cued hemifield to assess the degree to which IPS activations reflect stimulus specific or stimulus general processing consistent with the pure storage or internal attention hypotheses. These data revealed significant contralateral bias along regions IPS0-5 regardless of stimulus type. Also present was a weaker stimulus-based bias apparent in stronger left lateralized activations for verbal stimuli and stronger right lateralized activations for visuospatial stimuli. However, there was no consistent stimulus-based lateralization of activity. Thus, despite the observation of stimulus-based modulation of spatial lateralization this pattern was bilateral. As such, although it is quantitatively underspecified, our results are overall more consistent with an internal attention view that the IPS plays a material general role in

  17. A Productivity Enhancement Study of the FMSO (Fleet Material Support Office) Software Effort.

    DTIC Science & Technology

    1983-11-01

    Headquartc-rs Financial Systems. 3. .anagement Information System f0r Inte-na:igal Lc- gistics - MISIL. 4. Special Data P:c ~ssing Systems ?:zjects. a) RMM&E...Requisition Material moni:oring and ExpP- b) Irid.n- logistics data . c) NALCC:S. d) NArDS - Navy Au.cmatsf Tzrnporti-io: Da’a Sysem. s) 1AVADS...have changed ccnsiderably since FMSO’s equipment was ins-:alled. Iagnetic taps oriented syst.ems for data processing are now a thing of the past

  18. Material Testing in Support of the ISS Electrochemical Disinfection Feasibility Study

    NASA Technical Reports Server (NTRS)

    Clements, Anna; Shindo, David; Modica, Cathy

    2011-01-01

    The International Space Station Program recognizes the risk of microbial contamination in their potable and non-potable water sources. With the end of the Space Shuttle Program, the ability to send up shock-kits of biocides in the event of an outbreak becomes even more difficult. Currently, the US Segment water system relies primarily on iodine to mitigate contamination concerns. To date, several small cases of contamination have occurred which have been remediated. NASA, however, realizes that having a secondary method of combating a microbial outbreak is a prudent investment. NASA is looking into developing hardware that can generate biocides electrochemically, and potentially deploying that hardware. The specific biocides that the technology could generate include: hydrogen peroxide, oxone, hypochlorite and peracetic acid. In order to use these biocides on deployed water systems, the project must determine that all the materials in the potential application are compatible with the biocides at their anticipated administered concentrations. This paper will detail the materials test portion of the feasibility assessment including the plan for both metals and non-metals along with results to date.

  19. Synthesis of binder-like molecules covalently linked to silicon nanoparticles and application as anode material for lithium-ion batteries without the use of electrolyte additives

    NASA Astrophysics Data System (ADS)

    Assresahegn, Birhanu Desalegn; Bélanger, Daniel

    2017-03-01

    A chemically modified silicon anode is prepared for application as anode in lithium-ion batteries by covalent attachment of polyacrylic acid to enable self-adhesion between the active material particles. The polyacrylic acid polymer is formed by atom transfer radical polymerization using 1-(bromoethyl)benzene initiator groups initially bonded to a hydrogenated silicon surface. The grafting of 1-(bromoethyl)benzene and polyacrylic acid is confirmed by various material characterization techniques. The electrochemical performance of the silicon anodes is also evaluated by galvanostatic cycling. The chemically modified composite silicon anode (with active material loading of 0.9-1 mg cm-2) showed a significantly improved performance in terms of: gravimetric capacitance (more than 2000 mAh g-1) after 300 cycles and 80% capacity retention with an average 99.6% Coulombic efficiency at a current density of 0.34 A g-1. However, the unmodified electrode cycled 75 times in the same conditions only retains 46% of its initial capacity with an average 95.1% Coulombic efficiency. The new composite Si electrode performs better at high charge/discharge rate and allows the use of larger proportion of the active material by reducing the amount of binder. It is noteworthy that these composite silicon electrodes are tested without the use of expensive electrolyte additives.

  20. Lateral Diffusion of Proteins on Supported Lipid Bilayers: Additive Friction of Synaptotagmin 7 C2A–C2B Tandem Domains

    PubMed Central

    2015-01-01

    The synaptotagmin (Syt) family of proteins contains tandem C2 domains, C2A and C2B, which bind membranes in the presence of Ca2+ to trigger vesicle fusion during exocytosis. Despite recent progress, the role and extent of interdomain interactions between C2A and C2B in membrane binding remain unclear. To test whether the two domains interact on a planar lipid bilayer (i.e., experience thermodynamic interdomain contacts), diffusion of fluorescent-tagged C2A, C2B, and C2AB domains from human Syt7 was measured using total internal reflection fluorescence microscopy with single-particle tracking. The C2AB tandem exhibits a lateral diffusion constant approximately half the value of the isolated single domains and does not change when additional residues are engineered into the C2A–C2B linker. This is the expected result if C2A and C2B are separated when membrane-bound; theory predicts that C2AB diffusion would be faster if the two domains were close enough together to have interdomain contact. Stopped-flow measurements of membrane dissociation kinetics further support an absence of interdomain interactions, as dissociation kinetics of the C2AB tandem remain unchanged when rigid or flexible linker extensions are included. Together, the results suggest that the two C2 domains of Syt7 bind independently to planar membranes, in contrast to reported interdomain cooperativity in Syt1. PMID:25437758

  1. Nanoporous aluminum oxide as a novel support material for enzyme biosensors.

    PubMed

    Heilmann, A; Teuscher, N; Kiesow, A; Janasek, D; Spohn, U

    2003-10-01

    To construct novel amperometric sensors for the detection of hydrogen peroxide and pyruvate, peroxidase and pyruvate oxidase were immobilized in self-supporting nanoporous alumina membranes those made by anodic oxidation. Pyruvate oxidase and other enzymes were enclosed in poly(carbamoylsulfonate) hydrogel and sucked into the nanoporous alumina structure before polymerization. The alumina membranes were investigated by scanning electron microscopy before and after the enzyme immobilization. In an amperometric flow detector cell, pyruvate and hydrogen peroxide were detected under flow injection analysis conditions in concentration ranges from 1 microM to 100 microM and 5 microM to 500 microM, respectively. The achieved operational stability showed that alumina membranes can be used to construct enzyme-modified electrodes.

  2. Supporting online materials for mineralogy and petrology of Comet81P/Wild 2 nucleus samples

    SciTech Connect

    Zolensky, Michael E.; Zega, Thomas J.; Yano, Hajime; Wirick, Sue; Westphal, Andrew J.; Weisberg, Mike K.; Weber, Iris; Warren, Jack L.; Velbel, Michael A.; Tsuchiyama, Akira; Tsou, Peter; Toppani, Alice; Tomioka, Naotaka; Tomeoka, Kazushige; Teslich, Nick; Taheri, Mitra; Susini, Jean; Stroud, Rhonda; Stephan, Thomas; Stadermann, Frank J.; Snead, Christopher J.; Simon, Steven B.; Simionovici, Alexandre; See,Thomas H.; Robert Francois; Rietmeijer, Frans J.M.; Rao, William; Perronnet, Murielle C.; Papanastassiou, Dimitri A.; Okudaira, Kyoko; Ohsumi, Kazumasa; Ohnishi, Ichiro; Nakamura-Messenger, Keilo; Nakamura,Tomoki; Mostefaoui, Smail; Mikouchi, Takashi; Meibom, Anders; Matrajt,Graciela; Marcus, Matthew A.; Leroux, Hugues; Lemelle, Laurence; Antonio,Loan Le; Lanzirotti, Antonio; Langenhorst, Falko; Krot, Alexander N.; Keller, Lindsay P.; Kearsley, Anton T.; Joswiak, Davis; Jacob, Damien; Ishii, Hope; Harvey, Ralph; Hagiya, Kenji; Grossman, Lawrence; Grossman,Jeffrey N.; Graham, Giles A.; Gounelle, Matthieu; Gillet, Philippe; Genge, Matthew J.; Flynn, George; Ferroir, Tristan; Fallow, Stewart; Ebel, Denton S.; Dai, Zu Rong; Cordier, Patrick; Clark, Benton; Chi,Miaofang; Butterworth, Anna L.; Brownlee, Donald E.; Bridges, John C.; Brennan, Sean; Brearley, Adrian; Bradley, John P.; Bleuet, Pierre; Bland,Phil A.; Bastien, Ron

    2006-01-01

    The bulk of the comet 81P/Wild 2 (hereafter Wild 2) samples returned to Earth by the Stardust spacecraft appear to be weakly constructed mixtures of nanometer-scale grains, with occasional much larger (over 1 micrometer) ferromagnesian silicates, Fe-Ni sulfides, Fe-Ni metal, and accessory phases. The very wide range of olivine and low-Ca pyroxene compositions in comet Wild 2 requires a wide range of formation conditions, probably reflecting very different formation locations in the protoplanetary disk. The restricted compositional ranges of Fe-Ni sulfides, the wide range for silicates, and the absence of hydrous phases indicate that comet Wild 2 experienced little or no aqueous alteration. Less abundant Wild 2 materials include a refractory particle, whose presence appears to require radial transport in the early protoplanetary disk.

  3. Is an Apple Magnetic: Magnetic Response of Everyday Materials Supporting Views About the Nature of Science

    NASA Astrophysics Data System (ADS)

    Laumann, Daniel

    2017-03-01

    Magnetism and its various applications are essential for our daily life and for many technological developments. The term magnetism is almost always used as a synonym for ferromagnetism. However, the magnetic properties of the elements of the periodic table indicate that the vast majority of elements are not ferromagnetic, but rather, diamagnetic or paramagnetic. Typically, only ferromagnetism is discussed in classrooms, which can create a distorted picture. This article supplies the further development of an experiment demonstrating the dia- and paramagnetic properties with an electronic balance and a neodymium magnet. It focuses on an investigation of ordinary materials that occur in pupils' everyday environment. The experiment is applicable both for a quantitative measurement of the magnetic (volume) susceptibility χV and can serve as a phenomenological approach to dia- and paramagnetism. Moreover, it encourages a discussion about typical beliefs regarding the nature of science, comparing the behavior of common objects in weak and in strong magnetic fields.

  4. A hybrid plasma technology life support system for the generation of oxygen on Mars: Considerations on materials and geometry

    NASA Astrophysics Data System (ADS)

    Gruenwald, J.

    2016-06-01

    As there is a growing interest in conducting human missions to Mars, the need for suitable life support systems becomes more and more important. The reliability of such systems has to increase with the duration of manned missions. Furthermore the maintenance requirements have to be low in order to ensure their efficient use over a long period of time. A proposal for a hybrid life support system that is based on plasma technology for the creation of oxygen from the dissociation of carbon dioxide is given in this paper. The main focus lies on geometrical considerations regarding the optimal shape of the main reactor chamber as well as on suitable materials, which are most promising for the construction of such a system.

  5. Al-doped TiO2 mesoporous material supported Pd with enhanced catalytic activity for complete oxidation of ethanol

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Mu, Wentao; Su, Liqing; Li, Xingying; Guo, Yuyu; Zhang, Shen; Li, Zhe

    2017-04-01

    Pd catalysts supported on Al-doped TiO2 mesoporous materials were evaluated in complete oxidation of ethanol. The catalysts synthesized by wet impregnation based on evaporation-induced self-assembly were characterized by X-ray diffraction, measurement of pore structure, XPS, FT-IR, temperature programmed reduction and TEM. Characteristic results showed that the aluminium was doped into the lattice of mesoporous anatase TiO2 to form Al-O-Ti defect structure. Catalytic results revealed that Al-doped catalysts were much more active than the pristine one, especially at low temperature (≤200 °C). This should be ascribed to the introduction of aluminium ions that suppressed the strong metal-support interaction and increased the active sites of Pd oxides, enhanced the stabilized anatase TiO2, improved well dispersed high valence palladium species with high reducibility and enriched chemisorption oxygen.

  6. The Infrastructure Necessary to Support a Sustainable Material Protection, Control and Accounting (MPC&A) Program in Russia

    SciTech Connect

    Bachner, Katherine M.; Mladineo, Stephen V.

    2011-07-20

    The NNSA Material Protection, Control, and Accounting (MPC&A) program has been engaged for fifteen years in upgrading the security of nuclear materials in Russia. Part of the effort has been to establish the conditions necessary to ensure the long-term sustainability of nuclear security. A sustainable program of nuclear security requires the creation of an indigenous infrastructure, starting with sustained high level government commitment. This includes organizational development, training, maintenance, regulations, inspections, and a strong nuclear security culture. The provision of modern physical protection, control, and accounting equipment to the Russian Federation alone is not sufficient. Comprehensive infrastructure projects support the Russian Federation's ability to maintain the risk reduction achieved through upgrades to the equipment. To illustrate the contributions to security, and challenges of implementation, this paper discusses the history and next steps for an indigenous Tamper Indication Device (TID) program, and a Radiation Portal Monitoring (RPM) program.

  7. Microbial population in the biomass adhering to supporting material in a packed-bed reactor degrading organic solid waste.

    PubMed

    Sasaki, Kengo; Haruta, Shin; Ueno, Yoshiyuki; Ishii, Masaharu; Igarashi, Yasuo

    2007-06-01

    An anaerobic packed-bed reactor using carbon fiber textiles (CFT) as the supporting material was continuously operated using an artificial garbage slurry. 16S rRNA gene analysis showed that many bacteria in the biomass adhering to CFT were closely related to those observed from other anaerobic environments, although a wide variety of unidentified bacteria were also found. Dot blot hybridization results clarified that 16S rRNA levels of methanogens in the adhering biomass were higher than those in the effluent. Based on microscopic observation, the adhering biomass consisted of microorganisms, organic material, and void areas. Bacteria and Archaea detected by fluorescence in situ hybridization were distributed from the surface to the inner regions of the adhering biomass. Methanosarcina sp. tended to be more abundant in the inner part of the adhering biomass than at the surface. This is the first report to elucidate the structure of the microbial community on CFT in a packed-bed reactor.

  8. Novel functionalized polymeric fabric and fiber material as solid support for solid-phase synthesis and biomedical applications

    NASA Astrophysics Data System (ADS)

    Xiang, Bei

    The aim of the research is to develop novel polymer solid support by modifying or fabricating polymeric fibrous materials for peptide synthesis and biomedical applications. Originally chemical inert isotactic polypropylene (iPP) fabric was utilized and modified to serve as a functional flexible planar solid support for solid phase peptide synthesis. The modification was achieved through thermal initiated radical grafting polymerization using acrylic acid, poly (ethylene glycol) diacrylate as monomers, and benzoyl peroxide as radical initiator. The iPP fabric was successfully functionalized and possessing as high as 0.7mmol/g carboxylic acid groups. Peptide ligand LHPQF was successfully synthesized on the new functional planar support. Specific enzyme immobilization was fulfilled on the functional iPP fabric support. A commercially available ethylene-acrylic acid copolymer was made into ultrafine copolymer fiber bundles which are composed of nanofibers with diameters ranging from 200nm to 800nm. Various mixing ratios of copolymer/matrix materials were utilized to explore the effect on the final nanofiber physical properties including morphology and stability in solvents. The surface carboxylic acid groups were further converted to amino groups before the functional nanofibers can be applied in solid phase peptide synthesis. Two peptide ligands, LHPQF and HWRGWV, were also successfully synthesized on the nanofiber bundles. Streptavidin and human immunoglobulin G specific binding with the corresponding ligand which was anchored on the nanofibers was conducted successfully to illustrate the potential applications of the nanofiber materials in biomedical field. Further study on the dispersion of the ethylene-acrylic acid nanofiber bundles was pursued to take advantage of the super high active surface area of functional nanofibers. To manipulate the polymer nanofibers during synthesis and bio-assays, a technique was developed to controllably assemble and disperse the

  9. Optical Property Characterization of Far IR Materials Critical for CLARREO Mission Support

    NASA Astrophysics Data System (ADS)

    Hanssen, L. M.; Wilthan, B.; Mekhontsev, S.; Monte, C.; Hollandt, J.; McKenna, P.; Szczesniak, M.

    2010-12-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) and other climate science and remote sensing applications require accurate thermal and far infrared (IR) spectral radiance measurements, which are dependent on reference blackbody sources that have high and well-characterized spectral emissivity. The design and performance of blackbody sources are strongly affected by the spectral emittance of available coatings. Hence the emittance or reflectance of such coatings need to be accurately characterized. The measurement metrology for the reflectance of near-ambient targets in the thermal IR spectral range (2.5 to 15 microns) is well established and validated. The equivalent metrology for the far IR spectral range (15 to 50 microns and longer) is currently being established at National Measurement Institutes (NMIs), such as the National Institute of Standards and Technology (NIST) and at the Physikalisch-Technische Bundesanstalt (PTB), but will take several years to become operational and validated. Other existing facilities, such as at Surface Optics Corporation (SOC), do not have well characterized uncertainty budgets and are not traceable to the SI, but may be useful to provide support of the R&D for CLARREO. The direct measurement of the spectral emittance can also be used to obtain or validate reflectance data, but until cryo-vacuum facilities become fully functional at an NMI, such measurements are possible only for targets at elevated temperatures (typically above 200 °C). This limitation prevents the characterization of several critically important coatings. This paper describes ongoing efforts to establish the uncertainty of reflectance measurements at the SOC calibration facility over the far IR spectral range. For this purpose, NIST and PTB emittance facilities are used to measure the spectral emittance of transfer standard targets at 200 °C at wavelengths from 10 to 100 microns. Subsequently, these samples are measured at the SOC facility

  10. Telechelic Poly(2-oxazoline)s with a biocidal and a polymerizable terminal as collagenase inhibiting additive for long-term active antimicrobial dental materials

    PubMed Central

    Fik, Christoph P.; Konieczny, Stefan; Pashley, David H.; Waschinski, Christian J.; Ladisch, Reinhild S.; Salz, Ulrich; Bock, Thorsten; Tiller, Joerg C.

    2015-01-01

    Although modern dental repair materials show excellent mechanical and adhesion properties, they still face two major problems: First, any microbes that remain alive below the composite fillings actively decompose dentin and thus, subsequently cause secondary caries. Second, even if those microbes are killed, the extracellular proteases such as MMP, remain active and can still degrade collagenousdental tissue. In order to address both problems, a poly(2-methyloxazoline) with a biocidal quaternary ammonium and a polymerizable methacrylate terminal was explored as additive for a commercial dental adhesive. It could be demonstrated that the adhesive rendered the adhesive contact-active antimicrobial against S. mutans at a concentration of only 2.5 wt% and even constant washing with water for 101 days did not diminish this effect. Increasing the amount of the additive to 5 wt% allowed killing S. mutans cells in the tubuli of bovinedentin upon application of the adhesive. Further, the additive fully inhibited bacterial collagenase at a concentration of 0.5 wt% and reduced human recombinant collagenase MMP-9 to 13% of its original activity at that concentration. Human MMPs naturally bound to dentin were inhibited by more than 96% in a medium containing 5 wt% of the additive. Moreover, no adverse effect on the enamel/dentine shear bond strength was detected in combination with a dental composite. PMID:25130877

  11. Material selection and evaluation of new encapsulation compounds for electric cables for launch support system

    NASA Technical Reports Server (NTRS)

    Ray, Asit K.

    1992-01-01

    Eight urethane compounds were evaluated as possible replacement for the existing encapsulating compoounds for electrical cables for the Launch Support System at Kennedy Space Center (KSC). The existing encapsulating compound, PR-1535, contains the curative MOCA 4-4'-Methylene-BIS (2-chloroaniline), which is a suspect carcinogen and hence may be the subject of further restrictions of its use by the Occupational Safety and Health Administration (OSHA). The samples made in the configuration of cable joints and in the form of disks were evaluated for flammability and hypergolic compatibility. These also underwent accelerated weatherability tests that measured the residual hardness of the exposed samples. Three candidates and the existing compound passed the hardness test. Of these, only one candidate and the existing compound passed the flammability test. The thermal and hydrolytic stability (weatherability) of these samples was studied using thermogravimetric analysis (DSC) techniques. The TMA and DSC data correlated with the residual hardness data; whereas, the TGA data showed no correlation. A hypergolic compatibility test will be conducted on the compound V-356-HE80, which passed both the flammability and accelerated weatherability tests.

  12. Development and validation of a simple method for routine analysis of ractopamine hydrochloride in raw material and feed additives by HPLC.

    PubMed

    Freire, Ellen Figueiredo; Borges, Keyller Bastos; Tanimoto, Hélio; Nogueira, Raquel Tassara; Bertolini, Lucimara Cristiane Toso; de Gaitani, Cristiane Masetto

    2009-01-01

    A simple method was optimized and validated for determination of ractopamine hydrochloride (RAC) in raw material and feed additives by HPLC for use in quality control in veterinary industries. The best-optimized conditions were a C8 column (250 x 4.6 mm id, 5.0 microm particle size) at room temperature with acetonitrile-100 mM sodium acetate buffer (pH 5.0; 75 + 25, v/v) mobile phase at a flow rate of 1.0 mL/min and UV detection at 275 nm. With these conditions, the retention time of RAC was around 5.2 min, and standard curves were linear in the concentration range of 160-240 microg/mL (correlation coefficient > or = 0.999). Validation parameters, such as selectivity, linearity, limit of detection (ranged from 1.60 to 2.05 microg/mL), limit of quantification (ranged from 4.26 to 6.84 microg/mL), precision (relative standard deviation < or = 1.87%), accuracy (ranged from 96.97 to 100.54%), and robustness, gave results within acceptable ranges. Therefore, the developed method can be successfully applied for the routine quality control analysis of raw material and feed additives.

  13. [Simultaneous determination of eight additives in polymer food packaging materials by ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry].

    PubMed

    Zhang, Xulong; Liu, Yin; Gong, Zhiguo; Wang, Pengju; Wang, Jide; Feng, Shun

    2014-08-01

    An ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was proposed for the simultaneous determination of eight additives (Irgafos 168 (tri(2.4-di-tert-butylphenyl)phosphite), Irganox 1076 (octadecyl-β-(4-hydroxy-3, 5-di-tert-butylphenyl)propionate), Irganox 1010 (pentaerythritol tetrakys 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), BHA (butyl hydroxy anisole), TBHQ (tertiary butylhydroquinone), PG (propyl gallate), DG (dodecyl gallate), UV-326 (2-( 2'-hydroxyl-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole) in food packaging materials. After extracted by chloromethane through ultrasonic extraction, the samples were analyzed by UPLC-MS/MS. The chromatographic conditions were optimized, and the best separation was obtained on a Waters BEH-C18 column (50 mm x 2. 1 mm, 1.7 μm) with gradient elution of 0. 05% acetic acid solu- tion and methanol. The analysis was performed by UPLC-MS/MS with electrospray ionization (ESI) source in switching between the positive and negative ion modes in one run for multiple reaction monitoring. The eight additives showed good linear relationships in the ranges with all the correlation coefficients (R2) more than 0. 993. The limits of detection (LODs, S/N= 3) and limits of quantitation (LOQs, S/N= 10) of this method were 0. 13-5.50 μg/L and 0.45-17.50 μg/L, respectively. The recoveries were in the range of 63. 9% - 127. 0% with all the RSDs < 15. 8% (n= 6). This method is simple, accurate and effective for the analysis of the eight additives in food packaging materials.

  14. Preparation and characterization of new dental porcelains, using K-feldspar and quartz raw materials. Effect of B2O3 additions on sintering and mechanical properties.

    PubMed

    Harabi, Abdelhamid; Guerfa, Fatiha; Harabi, Esma; Benhassine, Mohamed-Tayeb; Foughali, Lazhar; Zaiou, Soumia

    2016-08-01

    The aim of this work was to determine the effect of temperature and boric oxide (B2O3) addition on sintering and mechanical properties of a newly developed dental porcelain (DP) prepared from local Algerian raw materials. Based on a preliminary work, the new selected composition was 75wt.% feldspar, 20wt.% quartz and 5wt.% kaolin. It was prepared by sintering the mixture at different temperatures (1100-1250°C). The optimum sintering conditions gave a relatively higher density (2.47g/cm(3)) and excellent mechanical properties. The three point flexural strength (3PFS) and Martens micro-hardness of dental porcelains were 149MPa and 2600MPa, respectively. This obtained 3PFS value is more than four times greater than that of hydroxyapatite (HA) value (about 37MPa) sintered under the same conditions. However, the sintering temperature was lowered by about 25 and 50°C for 3 and 5wt.% B2O3 additions, respectively. But, it did not improve furthermore the samples density and their mechanical properties. It has also been found that B2O3 additions provoke a glass matrix composition variation which delays the leucite formation during sintering.

  15. Nitrogen and oxygen functionalized hollow carbon materials: The capacitive enhancement by simply incorporating novel redox additives into H2SO4 electrolyte

    NASA Astrophysics Data System (ADS)

    Nie, Yong Fu; Wang, Qian; Chen, Xiang Ying; Zhang, Zhong Jie

    2016-07-01

    In present work, we have developed a simple but effective template carbonization method for producing hollow carbon materials with high content of nitrogen and oxygen from thiocarbanilide. Among all samples, the NPC-1 exhibits high specific surface area (736 m2 g-1) and large pore volume (5.93 cm3 g-1) with high content of heteroatoms (∼11.25 at% nitrogen and ∼5.74 at% oxygen), which is conducive to the improvement of electrochemical performance. Specifically, the high specific capacitance and excellent cycling stability over 5000 cycles of the NPC-1-based electrode are achieved in 1 mol L-1 H2SO4 electrolyte. Additionally, pyrocatechol and rutin as novel redox additives that can easily cause redox-reactions have been incorporated into H2SO4 electrolyte to improve the capacitances. As a result, the NPC-1-R-0.15 and NPC-1-P-0.15 samples deliver high specific capacitances of 120.5 and 368.7 F g-1 at 2 A g-1, respectively, which are much higher than that of the NPC-1 sample (66.2 F g-1) without redox-additives at same current density. Furthermore, the large energy density of 18.9 and 11.9 Wh kg-1 of the NPC-1-based symmetric supercapacitors have been obtained in H2SO4+pyrocatechol and H2SO4+rutin electrolyte, respectively, and both samples also demonstrate excellent cyclic performance for 5000 cycles.

  16. Hydrodechlorination of 1,1-dichlorotetrafluoroethane and dichlorodifluoromethane catalyzed by Pd on fluorinated aluminas: The role of support material

    SciTech Connect

    Early, K.; Kovalchuk, V.I.; Lonyi, F.; Deshmukh, S.; d`Itri, J.L.

    1999-02-15

    The gas phase hydrodechlorination of CF{sub 3}CFCl{sub 2} to CF{sub 3}CFH{sub 2} and CF{sub 2}Cl{sub 2} to CF{sub 2}H{sub 2} catalyzed by Pd supported on Al{sub 2}O{sub 3}, a series of fluorinated Al{sub 2}O{sub 3}, and AlF{sub 3} was investigated. A combination of reaction kinetics investigations and characterization by in situ FTIR spectroscopy has been performed. It has been found that for reactions involving CF{sub 3}CFCl{sub 2}, all catalysts exhibit a rapid and significant decrease in activity; however, little change in activity with time on stream occurs with CF{sub 2}Cl{sub 2}. FTIR investigations suggest the occurrence of direct reaction between the CFC and the support material, which results in the consumption of hydroxyl groups during the early stages of reaction. The effect of fluorination of support on catalytic behavior of Pd is discussed.

  17. Combination of material flow analysis and substance flow analysis: a powerful approach for decision support in waste management.

    PubMed

    Stanisavljevic, Nemanja; Brunner, Paul H

    2014-08-01

    The novelty of this paper is the demonstration of the effectiveness of combining material flow analysis (MFA) with substance flow analysis (SFA) for decision making in waste management. Both MFA and SFA are based on the mass balance principle. While MFA alone has been applied often for analysing material flows quantitatively and hence to determine the capacities of waste treatment processes, SFA is more demanding but instrumental in evaluating the performance of a waste management system regarding the goals "resource conservation" and "environmental protection". SFA focuses on the transformations of wastes during waste treatment: valuable as well as hazardous substances and their transformations are followed through the entire waste management system. A substance-based approach is required because the economic and environmental properties of the products of waste management - recycling goods, residues and emissions - are primarily determined by the content of specific precious or harmful substances. To support the case that MFA and SFA should be combined, a case study of waste management scenarios is presented. For three scenarios, total material flows are quantified by MFA, and the mass flows of six indicator substances (C, N, Cl, Cd, Pb, Hg) are determined by SFA. The combined results are compared to the status quo in view of fulfilling the goals of waste management. They clearly point out specific differences between the chosen scenarios, demonstrating potentials for improvement and the value of the combination of MFA/SFA for decision making in waste management.

  18. Zr-doped TiO2 supported on delaminated clay materials for solar photocatalytic treatment of emerging pollutants.

    PubMed

    Belver, C; Bedia, J; Rodriguez, J J

    2017-01-15

    Solar light-active Zr-doped TiO2 nanoparticles were successfully immobilized on delaminated clay materials by a one-step sol-gel route. Fixing the amount of TiO2 at 65wt.%, this work studies the influence of Zr loading (up to 2%) on the photocatalytic activity of the resulting Zr-doped TiO2/clay materials. The structural characterization demonstrates that all samples were formed by a delaminated clay with nanostructured anatase assembled on its surface. The Zr dopant was successfully incorporated into the anatase lattice, resulting in a slight deformation of the anatase crystal and the reduction of the band gap. These materials exhibit high surface area with a disordered mesoporous structure formed by TiO2 particles (15-20nm) supported on a delaminated clay. They were tested in the solar photodegradation of antipyrine, usually used as an analgesic drug and selected as an example of emerging pollutant. High degradation rates have been obtained at low antipyrine concentrations and high solar irradiation intensities with the Zr-doped TiO2/clay catalyst, more effective than the undoped one. This work demonstrates the potential application of the synthesis method for preparing novel and efficient solar-light photocatalysts based on metal-doped anatase and a delaminated clay.

  19. High performance addition-type thermoplastics (ATTs) - Evidence for the formation of a Diels-Alder adduct in the reaction of an acetylene-terminated material and a bismaleimide

    NASA Technical Reports Server (NTRS)

    Pater, R. H.; Soucek, M. D.; Chang, A. C.; Partos, R. D.

    1991-01-01

    Recently, the concept and demonstration of a new versatile synthetic reaction for making a large number of high-performance addition-type thermoplastics (ATTs) were reported. The synthesis shows promise for providing polymers having an attractive combination of easy processability, good toughness, respectable high temperature mechanical performance, and excellent thermo-oxidative stability. The new chemistry involves the reaction of an acetylene-terminated material with a bismaleimide or benzoquinone. In order to clarify the reaction mechanism, model compound studies were undertaken in solutions as well as in the solid state. The reaction products were purified by flash chromatography and characterized by conventional analytical techniques including NMR, FT-IR, UV-visible, mass spectroscopy, and high pressure liquid chromatography. The results are presented of the model compound studies which strongly support the formation of a Diels-Alder adduct in the reaction of an acetylene-terminated compound and a bismaleimide or benzoquinone.

  20. Studies on some feed additives and materials giving partial protection against the suppressive effect of ochratoxin A on egg production of laying hens.

    PubMed

    Stoev, Stoycho D

    2010-06-01

    The protective effects of various feed supplements against the harmful effect of ochratoxin A on egg production and sexual maturation of two-weeks old Plymouth Rock female chicks designed for laying hens were studied. A significant protective effect of the feed additives or materials: water extract of artichoke (WEA), sesame seed (SS), Roxazyme-G (RG) and l-beta phenylalanine (PHE) against the suppressive effect of ochratoxin A (OTA) on egg production of laying hens was found. A similar protection was also seen on the toxic effect of OTA on various internal organs of the same hens. A significant protection was found against the decrease of the weight or the quantity of eggs as well as against the delay of the beginning of the laying period of chicks, both of which were provoked by ochratoxin A. These protective effects were strongest in chicks treated with SS or WEA, but were slightest in chicks treated with l-beta PHE.

  1. Biofilm development during the start-up period of anaerobic biofilm reactors: the biofilm Archaea community is highly dependent on the support material.

    PubMed

    Habouzit, Frédéric; Hamelin, Jérôme; Santa-Catalina, Gaëlle; Steyer, Jean-P; Bernet, Nicolas

    2014-05-01

    To evaluate the impact of the nature of the support material on its colonization by a methanogenic consortium, four substrata made of different materials: polyvinyl chloride, 2 polyethylene and polypropylene were tested during the start-up of lab-scale fixed-film reactors. The reactor performances were evaluated and compared together with the analysis of the biofilms. Biofilm growth was quantified and the structure of bacterial and archaeal communities were characterized by molecular fingerprinting profiles (capillary electrophoresis-single strand conformation polymorphism). The composition of the inoculum was shown to have a major impact on the bacterial composition of the biofilm, whatever the nature of the support material or the organic loading rate applied to the reactors during the start-up period. In contrast, the biofilm archaeal populations were independent of the inoculum used but highly dependent on the support material. Supports favouring Archaea colonization, the limiting factor in the overall process, should be preferred.

  2. Biological regeneration of ferric (Fe3+) solution during desulphurisation of gaseous streams: effect of nutrients and support material.

    PubMed

    Mulopo, Jean; Schaefer, L

    2015-01-01

    This paper evaluates the biological regeneration of ferric Fe3+ solution during desulphurisation of gaseous streams. Hydrogen sulphide (H2S) is absorbed into aqueous ferric sulphate solution and oxidised to elemental sulphur, while ferric ions Fe3+ are reduced to ferrous ions Fe2+. During the industrial regeneration of Fe3+, nutrients and trace minerals usually provided in a laboratory setup are not present and this depletion of nutrients may have a negative impact on the bacteria responsible for ferrous iron oxidation and may probably affect the oxidation rate. In this study, the effect of nutrients and trace minerals on ferrous iron oxidation have been investigated and the results showed that the presence of nutrients and trace minerals affects the efficiency of bacterial Fe2+oxidation. The scanning electron microscopy analysis of the geotextile support material was also conducted and the results showed that the iron precipitate deposits appear to play a direct role on the bacterial biofilm formation.

  3. Detection and Identification of Leachables in Vaccine from Plastic Packaging Materials Using UPLC-QTOF MS with Self-Built Polymer Additives Library.

    PubMed

    Zhang, Yun; Sun, Shuqi; Xing, Xuebin; Du, Zhenxia; Guo, Qiaozhen; Yu, Wenlian

    2016-07-05

    The direct contact of plastic parts with the medical products raises the possibility that plastic-related contaminants (leachables) may be present in the finished medical product. The leachable components from plastic materials may impact the safety and efficacy of the final medical product, so identification and determination of the leachables are essential for the safety assessment of medical products. A method to identify main leachables-polymer additives in medical products was developed by ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF MS) and a self-built library. The library contains 174 additives and the information on their names, formulas, structures, retention times, fragments, classifications, origin, and corresponding MS(E) and MSMS spectra. The reliability of the construction process of the library was guaranteed by the system stability and suitability test. Identification parameters of library application, such as mass error, retention times, fragments, and isotope pattern, were evaluated. Leachables in real vaccine and the intermediates were identified using automatic library searching. In vaccine, the peak m/z 239.0887 that could not be assigned by the library was identified as dimethyl 2-hydroxy-1,3-cyclohexanedicarboxylate using a series of elucidation tools. As a result, the concentrations of leachables in vaccine and the intermediates ranged from 0.85 to 21.91 μg/L.

  4. Role of different additives and metallic micro minerals on the enhanced citric acid production by Aspergillus niger MNNG-115 using different carbohydrate materials.

    PubMed

    Ali, Sikander; Haq, Ikram-ul

    2005-01-01

    The present investigation deals with the promotry effect of different additives and metallic micro minerals on citric acid production by Aspergillus niger MNNG-115 using different carbohydrate materials. For this, sugar cane bagasse was fortified with sucrose salt medium. Ethanol and coconut oil at 3.0% (v/w) level increased citric acid productivity. Fluoroacetate at a concentration of 1.0 mg/ml bagasse enhanced the yield of citric acid significantly. However, the addition of ethanol and fluoroacetate after 6 h of growth gave the maximum conversion of available sugar to citric acid. In another study, influence of some metallic micro-minerals viz. copper sulphate, molybdenum sulphate, zinc sulphate and cobalt sulphate on microbial synthesis of citric acid using molasses medium was also carried out. It was found that copper sulphate and molybdenum sulphate remarkably enhanced the production of citric acid while zinc sulphate was not so effective. However, cobalt sulphate was the least effective for microbial biosynthesis of citric acid under the same experimental conditions. In case of CuSO(4), the strain of Aspergillus niger MNNG-115 showed enhanced citric productivity with experimental (9.80%) over the control (7.54%). In addition, the specific productivity of the culture at 30 ppm CuSO(4) (Q(p) = 0.012a g/g cells/h) was several folds higher than other all other concentrations. All kinetic parameters including yield coefficients and volumetric rates revealed the hyper productivity of citric acid by CuSO(4) using blackstrap molasses as the basal carbon source.

  5. Montmorillonite-supported Ag/TiO(2) nanoparticles: an efficient visible-light bacteria photodegradation material.

    PubMed

    Wu, Tong-Shun; Wang, Kai-Xue; Li, Guo-Dong; Sun, Shi-Yang; Sun, Jian; Chen, Jie-Sheng

    2010-02-01

    Montmorillonite (MMT)-supported Ag/TiO(2) composite (Ag/TiO(2)/MMT) has been prepared through a one-step, low-temperature solvothermal technique. Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) reveal that the Ag particles coated with TiO(2) nanoparticles are well-dispersed on the surface of MMT in the composite. As a support for the Ag/TiO(2) composite, the MMT prevents the loss of the catalyst during recycling test. This Ag/TiO(2)/MMT composite exhibits high photocatalytic activity and good recycling performance in the degradation of E. coli under visible light. The high visible-light photocatalytic activity of the Ag/TiO(2)/MMT composite is ascribed to the increase in surface active centers and the localized surface plasmon effect of the Ag nanoparticles. The Ag/TiO(2)/MMT materials with excellent stability, recyclability, and bactericidal activities are promising photocatalysts for application in decontamination.

  6. Radiation dose assessments to support evaluations of radiological control levels for recycling or reuse of materials and equipment

    SciTech Connect

    Hill, R.L.; Aaberg, R.L.; Baker, D.A.; Kennedy, W.E. Jr.

    1995-07-01

    Pacific Northwest Laboratory is providing Environmental Protection Support and Assistance to the USDOE, Office of Environmental Guidance. Air, Water, and Radiation Division. As part of this effort, PNL is collecting data and conducting technical evaluations to support DOE analyses of the feasibility of developing radiological control levels for recycling or reuse of metals, concrete, or equipment containing residual radioactive contamination from DOE operations. The radiological control levels will be risk-based, as developed through a radiation exposure scenario and pathway analysis. The analysis will include evaluation of relevant radionuclides, potential mechanisms of exposure, and both health and non-health-related impacts. The main objective of this report is to develop a methodology for establishing radiological control levels for recycle or reuse. This report provides the results of the radiation exposure scenario and pathway analyses for 42 key radionuclides generated during DOE operations that may be contained in metals or equipment considered for either recycling or reuse. The scenarios and information developed by the IAEA. Application of Exemption Principles to the Recycle and Reuse of Materials from Nuclear Facilities, are used as the initial basis for this study. The analyses were performed for both selected worker populations at metal smelters and for the public downwind of a smelter facility. Doses to the public downwind were estimated using the US (EPA) CAP88-PC computer code with generic data on atmospheric dispersion and population density. Potential non-health-related effects of residual activity on electronics and on film were also analyzed.

  7. Development of Standard Reference Materials to support assessment of iodine status for nutritional and public health purposes.

    PubMed

    Long, Stephen E; Catron, Brittany L; Boggs, Ashley Sp; Tai, Susan Sc; Wise, Stephen A

    2016-09-01

    The use of urinary iodine as an indicator of iodine status relies in part on the accuracy of the analytical measurement of iodine in urine. Likewise, the use of dietary iodine intake as an indicator of iodine status relies in part on the accuracy of the analytical measurement of iodine in dietary sources, including foods and dietary supplements. Similarly, the use of specific serum biomarkers of thyroid function to screen for both iodine deficiency and iodine excess relies in part on the accuracy of the analytical measurement of those biomarkers. The National Institute of Standards and Technology has been working with the NIH Office of Dietary Supplements for several years to develop higher-order reference measurement procedures and Standard Reference Materials to support the validation of new routine analytical methods for iodine in foods and dietary supplements, for urinary iodine, and for several serum biomarkers of thyroid function including thyroid-stimulating hormone, thyroglobulin, total and free thyroxine, and total and free triiodothyronine. These materials and methods have the potential to improve the assessment of iodine status and thyroid function in observational studies and clinical trials, thereby promoting public health efforts related to iodine nutrition.

  8. Flexible and self-powered temperature-pressure dual-parameter sensors using microstructure-frame-supported organic thermoelectric materials

    NASA Astrophysics Data System (ADS)

    Zhang, Fengjiao; Zang, Yaping; Huang, Dazhen; di, Chong-An; Zhu, Daoben

    2015-09-01

    Skin-like temperature- and pressure-sensing capabilities are essential features for the next generation of artificial intelligent products. Previous studies of e-skin and smart elements have focused on flexible pressure sensors, whereas the simultaneous and sensitive detection of temperature and pressure with a single device remains a challenge. Here we report developing flexible dual-parameter temperature-pressure sensors based on microstructure-frame-supported organic thermoelectric (MFSOTE) materials. The effective transduction of temperature and pressure stimuli into two independent electrical signals permits the instantaneous sensing of temperature and pressure with an accurate temperature resolution of <0.1 K and a high-pressure-sensing sensitivity of up to 28.9 kPa-1. More importantly, these dual-parameter sensors can be self-powered with outstanding sensing performance. The excellent sensing properties of MFSOTE-based devices, together with their unique advantages of low cost and large-area fabrication, make MFSOTE materials possess promising applications in e-skin and health-monitoring elements.

  9. Development of hybrid materials based on sponge supported reduced graphene oxide and transition metal hydroxides for hybrid energy storage devices

    PubMed Central

    Dubal, Deepak P.; Holze, Rudolf; Gomez-Romero, Pedro

    2014-01-01

    Earnest efforts have been taken to design hybrid energy storage devices using hybrid electrodes based on capacitive (rGO) and pseudocapacitive (Ni(OH)2 and Co(OH)2) materials deposited on the skeleton of 3D macroporous (indicate sponge material) sponge support. Conducting framework was formed by coating rGO on macroporous sponge on which subsequent deposition of Ni(OH)2 and Co(OH)2 was carried out. The synergetic combination of rGO and Ni(OH)2 or Co(OH)2) provides dual charge-storing mechanisms whereas 3D framework of sponge allows excellent accessibility of electrolyte to hybrid electrodes. Moreover, to further increase the energy density, hybrid devices have been fabricated with SP@rGO@Ni or SP@rGO@Co and SP@rGO as positive and negative electrodes, respectively. These hybrid devices operate with extended operating voltage windows and achieve remarkable electrochemical supercapacitive properties which make them truly promising energy storage devices for commercial production. PMID:25483007

  10. Flexible and self-powered temperature–pressure dual-parameter sensors using microstructure-frame-supported organic thermoelectric materials

    PubMed Central

    Zhang, Fengjiao; Zang, Yaping; Huang, Dazhen; Di, Chong-an; Zhu, Daoben

    2015-01-01

    Skin-like temperature- and pressure-sensing capabilities are essential features for the next generation of artificial intelligent products. Previous studies of e-skin and smart elements have focused on flexible pressure sensors, whereas the simultaneous and sensitive detection of temperature and pressure with a single device remains a challenge. Here we report developing flexible dual-parameter temperature–pressure sensors based on microstructure-frame-supported organic thermoelectric (MFSOTE) materials. The effective transduction of temperature and pressure stimuli into two independent electrical signals permits the instantaneous sensing of temperature and pressure with an accurate temperature resolution of <0.1 K and a high-pressure-sensing sensitivity of up to 28.9 kPa−1. More importantly, these dual-parameter sensors can be self-powered with outstanding sensing performance. The excellent sensing properties of MFSOTE-based devices, together with their unique advantages of low cost and large-area fabrication, make MFSOTE materials possess promising applications in e-skin and health-monitoring elements. PMID:26387591

  11. Development of hybrid materials based on sponge supported reduced graphene oxide and transition metal hydroxides for hybrid energy storage devices.

    PubMed

    Dubal, Deepak P; Holze, Rudolf; Gomez-Romero, Pedro

    2014-12-08

    Earnest efforts have been taken to design hybrid energy storage devices using hybrid electrodes based on capacitive (rGO) and pseudocapacitive (Ni(OH)2 and Co(OH)2) materials deposited on the skeleton of 3D macroporous (indicate sponge material) sponge support. Conducting framework was formed by coating rGO on macroporous sponge on which subsequent deposition of Ni(OH)2 and Co(OH)2 was carried out. The synergetic combination of rGO and Ni(OH)2 or Co(OH)2) provides dual charge-storing mechanisms whereas 3D framework of sponge allows excellent accessibility of electrolyte to hybrid electrodes. Moreover, to further increase the energy density, hybrid devices have been fabricated with SP@rGO@Ni or SP@rGO@Co and SP@rGO as positive and negative electrodes, respectively. These hybrid devices operate with extended operating voltage windows and achieve remarkable electrochemical supercapacitive properties which make them truly promising energy storage devices for commercial production.

  12. A New Class of Risk-Importance Measures to Support Reactor Aging Management and the Prioritization of Materials Degradation Research

    SciTech Connect

    Unwin, Stephen D.; Lowry, Peter P.; Toyooka, Michael Y.

    2010-06-07

    As the US fleet of light water reactors ages, the risks of operation might be expected to increase. Although probabilistic risk assessment has proven a critical resource in risk-informed regulatory decision-making, limitations in current methods and models have constrained their prospective value in reactor aging management. These limitations stem principally from the use of static component failure rate models (which do not allow the impact of component aging on failure rates to be represented) and a very limited treatment of passive components (which would be expected to have an increasingly significant risk contribution in an aging system). Yet, a PRA captures a substantial knowledge base that could be of significant value in addressing plant aging. In this paper we will describe a methodology and a new class of risk importance measures that allow the use of an existing PRA model to support the management of plant aging, the prioritization of improvements to non-destructive examination and monitoring techniques, and the establishment of research emphases in materials science. This methodology makes use of data resources generated under the USNRC Proactive Management of Materials Degradation program which addresses the anticipated effects of numerous aging degradation mechanisms on a wide variety of component types.

  13. Investigating the Use and Effectiveness of Diverse Types of Materials in the Delivery and Support of Lab Sessions for Multimedia Subjects and Students

    ERIC Educational Resources Information Center

    Tsekleves, Emmanuel; Aggoun, Amar; Cosmas, John

    2013-01-01

    This research study explores the use of different lab material, investigating which types of materials contribute the most to the delivery and support of laboratory (lab) sessions to design, skill-based and technical courses in higher education in the UK. A qualitative research methodology was employed for this investigation and included both key…

  14. Single-walled carbon nanotubes as supporting structures and stimulating materials for NG108-15 neuroblastoma-glioma hybrid culture cells

    NASA Astrophysics Data System (ADS)

    Gheith, Muhammed Khameis

    Scope and method of study. Understanding the nature of interfacing inorganic materials, such as single-walled carbon nanotubes (SWNTs), with living cells is very crucial for the successful utilization of such man-made materials in biological and biomedical applications. The present study illustrates such a possible application where the mechanical and the electrical properties of SWNTs were utilized to design novel structures that were used as supporting platforms and stimulating substrates for NG108-15 hybrid neuronal cells. Composites of nanotubes were prepared using the layer-by-layer (LBL) assembly following the surface modification of the nanotubes with positively charged amphiphilic polymer that served as dispersing and stabilizing agent of the nanotubes. The functionalization of the nanotubes was characterized using Raman and absorption spectroscopic in addition to high-resolution transmission electron and atomic force microscopic techniques. The feasibility of the modified nanotube structures, films or freestanding, as supporting and stimulating substrates for neuronal growth and differentiation was investigated. Scanning electron and confocal microscopic techniques were mainly used to characterize the growth of the cells on the nanotube structures. Electrical coupling between the cells and the modified nanotube composites was investigated using the whole cell patch clamp technique. Findings and conclusions. The used polymer was seen to wrap around the nanotubes in a non-covalent attachment. Its presence on the nanotubes surface imparts a positive surface charge that facilitate the attachment of the cells to the formed nanotube structures. The LBL composites of the modified nanotubes were proven biocompatible to the NG108-15 cells growth and supported the long-term viability of these cells. Better cells differentiation was observed on the surface of the positively-charged nanotube films as compared to that on the surface of a negatively charged culture dish

  15. The Importance of a Theory-Informed Understanding of Additive Bilingual Education: Supporting Bilingualism and Biliteracy in a Melbourne Primary School

    ERIC Educational Resources Information Center

    Molyneux, Paul

    2006-01-01

    While Government commitments to supporting instruction in languages other than English have largely been honoured, bilingual education as a form of learning has not been widespread. Acknowledging the benefits of learning a language other than English, the most recent Australian national languages policy statement nonetheless makes no mention of…

  16. Final Environmental Assessment for Construction of an Addition to Support the Joint Strike Fighter Reprogramming Facility, Building 614, on Eglin Air Force Base, Florida

    DTIC Science & Technology

    2007-01-01

    their standards take into account special risks to children. The proposed site is located approximately 0.8 miles south of Lewis Middle School ...fireproofing, and other material used for soundproofing or insulation. ● Lead-Based Paint – LBP is defined as paint on surfaces that contains lead in excess

  17. Investigation of titanium nitride as catalyst support material and development of durable electrocatalysts for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Avasarala, Bharat K.

    The impending energy and climatic crisis makes it imperative for human society to seek non-fossil based alternative sources for our energy needs. Although many alternative energy technologies are currently being developed, fuel cell technology provides energy solutions, which satisfy a wide range of applications. But the current fuel cell technology is far from its target of large scale commercialization mainly because of its high cost and poor durability. Considerable work has been done in reducing the cost but its durability still needs significant improvement. Of the various materials in a PEM fuel cell, the degradation of electrocatalyst affects its durability the most, leading to performance loss. Carbon black (C) support corrosion plays a significant role in the electrocatalyst degradation and its severe affects due to potential cycling has been identified through my research. Through my resaerch, I introduce titanium nitride nanoparticles (TiN NP) as alternative catalyst supports replacing carbon black. TiN NP has higher electrical conductivity and corrosion resistance compared to that of C. The physical and electrochemical properties of TiN NP were studied and the Pt/TiN electrocatalyst was synthesized using polyol process. Upon optimizing using DOE, for desired catalyst particle size and activity, Pt/TiN is shown to have higher catalytic performance than conventional Pt/C. TiN NP are significantly influenced by the electrochemical conditions and show 'active' or 'passive' nature depending on the temperature and acidic concentration; and a temperature dependence model is proposed to understand the active/passive nature of TiN NP. A one-to-one comparison between TiN NP and C electrodes under similar electrochemical conditions show a superior performance of TiN NP as a catalyst support. The durability of the Pt/TiN electrocatalyst is also tested and it agrees well with the proposed model of active/passive nature of the TiN NP. Through theoretical calculation

  18. High-throughput characterization of Pt supported on thin film oxide material libraries applied in the oxygen reduction reaction.

    PubMed

    Schäfer, Dominik; Mardare, Cezarina; Savan, Alan; Sanchez, Miguel D; Mei, Bastian; Xia, Wei; Muhler, Martin; Ludwig, Alfred; Schuhmann, Wolfgang

    2011-03-15

    Thin film metal oxide material libraries were prepared by sputter deposition of nanoscale Ti/Nb precursor multilayers followed by ex situ oxidation. The metal composition was varied from 6 at.% Nb to 27 at.% Nb. Additionally, thin wedge-type layers of Pt with a nominal thickness gradient from 0 to 5 nm were sputter-deposited on top of the oxides. The materials libraries were characterized with respect to metallic film composition, oxide thickness, phases, electrical conductivity, Pt thickness, and electrochemical activity for the oxygen reduction reaction (ORR). Electrochemical investigations were carried out by cyclic voltammetry using an automated scanning droplet cell. For a nominal Pt thickness >1 nm, no significant dependence of the ORR activity on the Pt thickness or the substrate composition was observed. However, below that critical thickness, a strong decrease of the surface-normalized activity in terms of reduction currents and potentials was observed. For such thin Pt layers, the conductivity of the substrate seems to have a substantial impact on the catalytic activity. Results from X-ray photoelectron spectroscopy (XPS) measurements suggest that the critical Pt thickness coincides with the transition from a continuous Pt film into isolated particles at decreasing nominal Pt thickness. In the case of isolated Pt particles, the activity of Pt decisively depends on its ability to exchange electrons with the oxide layer, and hence, a dependence on the substrate conductivity is rationalized.

  19. Utilization of specific and non-specific peptide interactions with inorganic nanomaterials on the surface of bacteriophage M13: Methodologies towards phage supported bi-functional materials

    NASA Astrophysics Data System (ADS)

    Avery, Kendra Nicole

    the phage with a negative charge on which nanomaterials can be supported. Metal salt precursors reduced in the presence of WT M13 are studied in this chapter. Metal salt precursors of Fe, Co, Ru, Rh and Pd seem to be the most effective at coating the surface of the phage based on the positively charged metal-aquo complexes formed in water, which are attracted to the negative pVIII region. Other types of reactions are explored with WT phage as a scaffold such as conversion chemistry in a polyol solvent to access several intermetallic phases as well as co-precipitation reactions to access ternary oxides. Chapter 4 focuses on combining research from chapter 2 and chapter 3 to create a bi-functional material that utilizes both specific and non-specific peptide interactions with inorganic materials on the surface of M13 to attach two different types of nanomaterials. The example provided here is a magnetically recoverable hydrogenation catalyst made up of a pVIII region coated with rhodium nanoparticles held in place by non-specific peptide interactions and a pIII region attached to iron oxide nanoparticles via specific peptide interactions. This is the first example in the literature of a commercially available pIII bioengineered M13 bacteriophage forming a bi-functional material. This research provides a methodology to design and build single and multi-component materials on the surface of bacteriophage M13 without the necessity for additional bioengineering and library characterization. The simplicity of use will make the technique available to a wider variety of researchers in the materials science community.

  20. Establishment of a reference collection of additives and an analytical handbook of reference data to support enforcement of EU regulations on food contact plastics.

    PubMed

    van Lierop, B; Castle, L; Feigenbaum, A; Ehlert, K; Boenke, A

    1998-10-01

    A collection has been made of additives that are required as analytical standards for enforcement of European Union legislation on food contact plastics. The 100 additives have been characterized by mass spectrometry, infra-red spectroscopy and proton nuclear magnetic resonance spectroscopy to provide reference spectra. Gas chromatographic retention times have been recorded to facilitate identification by retention index. This information has been further supplemented by physico-chemical data. Finally, chromatographic methods have been used to indicate the presence of any impurities in the commercial chemicals. Samples of the reference substances are available on request and the collection of spectra and other information will be made available in printed format and on-line through the Internet. This paper gives an overview of the work done to establish the reference collection and the spectral atlas, which together will assist enforcement laboratories in the characterization of plastics and the selection of analytical methods for additives that may migrate.

  1. In Arabidopsis thaliana distinct alleles encoding mitochondrial RNA PROCESSING FACTOR 4 support the generation of additional 5' termini of ccmB transcripts.

    PubMed

    Stoll, Katrin; Jonietz, Christian; Schleicher, Sarah; des Francs-Small, Catherine Colas; Small, Ian; Binder, Stefan

    2017-04-01

    In plant mitochondria, the 5' ends of many transcripts are generated post-transcriptionally. We show that the pentatricopeptide repeat (PPR) protein RNA PROCESSING FACTOR 4 (RPF4) supports the generation of extra 5' ends of ccmB transcripts in Landsberg erecta (Ler) and a number of other Arabidopsis thaliana ecotypes. RPF4 was identified in Ler applying a forward genetic approach supported by complementation studies of ecotype Columbia (Col), which generates the Ler-type extra ccmB 5' termini only after the introduction of the RPF4 allele from Ler. Studies with chimeric RPF4 proteins composed of various parts of the RPF4 proteins from Ler and Col identified differences in the N-terminal and central PPR motifs that explain ecotype-specific variations in ccmB processing. These results fit well with binding site predictions in ccmB transcripts based on the known determinants of nucleotide base recognition by PPR motifs.

  2. Green technology effect of injection pressure, timing and compression ratio in constant pressure heat addition cycle by an eco-friendly material.

    PubMed

    Karthikayan, S; Sankaranarayanan, G; Karthikeyan, R

    2015-11-01

    Present energy strategies focus on environmental issues, especially environmental pollution prevention and control by eco-friendly green technologies. This includes, increase in the energy supplies, encouraging cleaner and more efficient energy management, addressing air pollution, greenhouse effect, global warming, and climate change. Biofuels provide the panorama of new fiscal opportunities for people in rural area for meeting their need and also the demand of the local market. Biofuels concern protection of the environment and job creation. Renewable energy sources are self-reliance resources, have the potential in energy management with less emissions of air pollutants. Biofuels are expected to reduce dependability on imported crude oil with connected economic susceptibility, reduce greenhouse gases, other pollutants and invigorate the economy by increasing demand and prices for agricultural products. The use of neat paradise tree oil and induction of eco-friendly material Hydrogen through inlet manifold in a constant pressure heat addition cycle engine (diesel engine) with optimized engine operating parameters such as injection timing, injection pressure and compression ratio. The results shows the heat utilization efficiency for neat vegetable oil is 29% and neat oil with 15% Hydrogen as 33%. The exhaust gas temperature (EGT) for 15% of H2 share as 450°C at full load and the heat release of 80J/deg. crank angle for 15% Hydrogen energy share.

  3. Effect of high-pressure/temperature (HP/T) treatments of in-package food on additive migration from conventional and bio-sourced materials.

    PubMed

    Mauricio-Iglesias, M; Jansana, S; Peyron, S; Gontard, N; Guillard, V

    2010-01-01

    Migration was assessed during and after two high-pressure/temperature (HP/T) treatments intended for a pasteurization (800 MPa for 5 min, from 20 to 40 degrees C) and a sterilization treatment (800 MPa for 5 min, from 90 to 115 degrees C) and were compared with conventional pasteurization and sterilization, respectively. The specific migration of actual packaging additives used as antioxidants and ultraviolet light absorbers (Irganox 1076, Uvitex OB) was investigated in a number of food-packaging systems combining one synthetic common packaging (LLDPE) and a bio-sourced one (PLA) in contact with the four food-simulating liquids defined by European Commission regulations. After standard HP/T processing, migration kinetics was followed during the service life of the packaging material using Fourier transform infrared spectrometer (FTIR) spectroscopy. LLDPE withstood the high-pressure sterilization, whereas it melted during the conventional sterilization. No difference was observed on migration from LLDPE for both treatments. In the case of PLA, migration of Uvitex OB was very low or not detectable for all the cases studied.

  4. Understanding the effects of a multi-functionalized additive on the cathode-electrolyte interfacial stability of Ni-rich materials

    NASA Astrophysics Data System (ADS)

    Yim, Taeeun; Kang, Kyoung Seok; Mun, Junyoung; Lim, Sang Hoo; Woo, Sang-Gil; Kim, Ki Jae; Park, Min-Sik; Cho, Woosuk; Song, Jun Ho; Han, Young-Kyu; Yu, Ji-Sang; Kim, Young-Jun

    2016-01-01

    Nickel-rich lithium nickel cobalt manganese oxides have received considerable attention as a promising cathode material, however, they have suffered from poor interfacial stability, especially at high temperature. Here, we suggest a bi-functionalized divinyl sulfone that enhances the applicability of a nickel-rich cathode via stabilization of the electrolyte-electrode interface. The divinyl sulfone forms a protective layer on the cathode surface by electrochemical oxidation reactions and this greatly decreases the internal pressure of the cell via stabilization of the Ni-rich cathode-electrolyte interface. The cell controlled with divinyl sulfone shows remarkable cycling performance with 91.9% capacity retention at elevated temperature even after 100 cycles. Additional electrode analyses and first-principles calculations provide critical spectroscopic evidences to demonstrate the combined effects of the sulfone and vinyl functional groups. Once the divinyl sulfone is electrochemically oxidized, the vinyl functional groups readily participate in further stabilizing sulfone-based solid electrolyte interphase intermediates and afford a durable protective layer on the nickel-rich electrode surface.

  5. Hydroxyapatite formation on titania-based materials in a solution mimicking body fluid: Effects of manganese and iron addition in anatase.

    PubMed

    Shin, Euisup; Kim, Ill Yong; Cho, Sung Baek; Ohtsuki, Chikara

    2015-03-01

    Hydroxyapatite formation on the surfaces of implanted materials plays an important role in osteoconduction of bone substitutes in bone tissues. Titania hydrogels are known to instigate hydroxyapatite formation in a solution mimicking human blood plasma. To date, the relationship between the surface characteristics of titania and hydroxyapatite formation on its surface remains unclear. In this study, titania powders with varying surface characteristics were prepared by addition of manganese or iron to examine hydroxyapatite formation in a type of simulated body fluid (Kokubo solution). Hydroxyapatite formation was monitored by observation of deposited particles with scale-like morphology on the prepared titania powders. The effect of the titania surface characteristics, i.e., crystal structure, zeta potential, hydroxy group content, and specific surface area, on hydroxyapatite formation was examined. Hydroxyapatite formation was observed on the surface of titania powders that were primarily anatase, and featured a negative zeta potential and low specific surface areas irrespective of the hydroxy group content. High specific surface areas inhibited the formation of hydroxyapatite because calcium and phosphate ions were mostly consumed by adsorption on the titania surface. Thus, these surface characteristics of titania determine its osteoconductivity following exposure to body fluid.

  6. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online.

  7. Characterization of Space Shuttle External Tank Thermal Protection System (TPS) Materials in Support of the Columbia Accident Investigation

    NASA Technical Reports Server (NTRS)

    Wingard, Charles D.

    2004-01-01

    NASA suffered the loss of the seven-member crew of the Space Shuttle Columbia on February 1, 2003 when the vehicle broke apart upon re-entry to the Earth's atmosphere. The final report of the Columbia Accident Investigation Board (CAIB) determined that the accident was caused by a launch ascent incident-a suitcase-sized chunk of insulating foam on the Shuttle's External Tank (ET) broke off, and moving at almost 500 mph, struck an area of the leading edge of the Shuttle s left wing. As a result, one or more of the protective Reinforced Carbon-Carbon (RCC) panels on the wing leading edge were damaged. Upon re-entry, superheated air approaching 3,000 F breached the wing damage and caused the vehicle breakup and loss of crew. The large chunk of insulating foam that broke off during the Columbia launch was determined to come from the so-called bipod ramp area where the Shuttle s orbiter (containing crew) is attached to the ET. Underneath the foam in the bipod ramp area is a layer of TPS that is a cork-filled silicone rubber composite. In March 2003, the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama received cured samples of the foam and composite for testing from the Michoud Assembly Facility (MAF) in New Orleans, Louisiana. The MAF is where the Shuttle's ET is manufactured. The foam and composite TPS materials for the ET have been well characterized for mechanical property data at the super-cold temperatures of the liquid oxygen and hydrogen fuels used in the ET. However, modulus data on these materials is not as well characterized. The TA Instruments 2980 Dynamic Mechanical Analyzer (DMA) was used to determine the modulus of the two TPS materials over a range of -145 to 95 C in the dual cantilever bending mode. Multi-strain, fixed frequency DMA tests were followed by multi-frequency, fixed strain tests to determine the approximate bounds of linear viscoelastic behavior for the two materials. Additional information is included in the original extended

  8. Chemistry and Materials Science Weapons-Supporting Research and Laboratory-Directed Research and Development. Second half progress report, FY 1993

    SciTech Connect

    Not Available

    1994-02-01

    Thrust areas of the weapons-supporting research are surface research, uranium research, physics and processing of metals, energetic materials. Group study areas included strength of Al and Al-Mg/alumina bonds, advanced synchrotron radiation study of materials, and theory, modeling, and computation. Individual projects were life prediction for composites and thermoelectric materials with exceptional figures of merit. The laboratory-directed R and D include director`s initiatives (aerogel-based electronic devices, molecular levels of energetic materials), individual projects, and transactinium institute studies. An author index is provided.

  9. The addition of decision support into computerized physician order entry reduces red blood cell transfusion resource utilization in the intensive care unit.

    PubMed

    Fernández Pérez, Evans R; Winters, Jeffrey L; Gajic, Ognjen

    2007-07-01

    Computerized physician order entry (CPOE) has the potential for cost containment in critically ill patients through practice standardization and elimination of unnecessary interventions. Previous study demonstrated the beneficial short-term effect of adding a decision support for red blood cell (RBC) transfusion into the hospital CPOE. We evaluated the effect of such intervention on RBC resource utilization during the two-year study period. From the institutional APACHE III database we identified 2,200 patients with anemia, but no active bleeding on admission: 1,100 during a year before and 1,100 during a year after the intervention. The mean number of RBC transfusions per patient decreased from 1.5 +/- 1.9 units to 1.3 +/- 1.8 units after the intervention (P = 0.045). RBC transfusion cost decreased from $616,442 to $556,226 after the intervention. Hospital length of stay and adjusted hospital mortality did not differ before and after protocol implementation. In conclusion, the implementation of an evidenced-based decision support system through a CPOE can decrease RBC transfusion resource utilization in critically ill patients.

  10. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  11. Additional case of Marden-Walker syndrome: support for the autosomal-recessive inheritance adn refinement of phenotype in a surviving patient.

    PubMed

    Orrico, A; Galli, L; Zappella, M; Orsi, A; Hayek, G

    2001-02-01

    In this report, we present a 14-year-old girl, born to consanguineous parents, who presented with severe mental retardation, hypotonia, short stature, and congenital joint contractures. The craniofacial features were scaphocephaly, thin/long and immobile face, marked hypoplasia of the midface, temporal narrowness, blepharophimosis, palpebral ptosis, and strabismus. The combination of such a distinctive craniofacial appearance and psychomotor retardation allows us to recognize a new case of the Marden-Walker syndrome. Our patient represents one of the rare cases in which consanguineous mating supports the autosomal-recessive pattern of inheritance of this condition. Furthermore, through refining the phenotype of a surviving patient, this report may contribute to a better recognition of this disorder in older affected children.

  12. Influence of Al 2O 3 additions on the crystallization mechanism and properties of diopside/anorthite hybrid glass-ceramics for LED packaging materials

    NASA Astrophysics Data System (ADS)

    Kang, Mina; Kang, Seunggu

    2011-07-01

    The crystallization mechanism and properties of diopside (CaMgSi 2O 6)/anorthite (CaAl 2Si 2O 8) hybrid glass-ceramics fabricated from a CMSA (CaO-MgO-SiO 2-Al 2O 3) glass system were studied as a function of Al 2O 3 additions. The parent glass prepared was pressed to pellets isostatically and was sintered to produce glass-ceramics. A non-isothermal analysis was performed to study the crystallization behavior of diopside/anorthite hybrid glass-ceramics using differential thermal analysis (DTA) with various heating rates (5-20 K min -1) and John-Mehl-Avrami and Kissinger equations. The occupying ratio of diopside and anorthite phases, crystal identification and microstructure in the glass-ceramics containing various Al 2O 3 contents were analyzed. Also the thermal conductivity and density of diopside/anorthite composites were measured to apply to LED packaging materials. The main crystalline phases for CaO-MgO-SiO 2-Al 2O 3 glass-ceramics system containing 8.6 wt% or less Al 2O 3, and 15.9 wt% or more Al 2O 3 were the diopside and anorthite, respectively. The difference (Δ T) of initiation temperature for crystallized ( Tx) and glass transition temperature ( Tg), calculated from the DTA curve for a glass is inversely proportional to the density of glass-ceramics fabricated from the glass. The highest crystallization temperature was 946 °C for the glass-ceramics containing 27.4 wt% Al 2O 3, which is low enough to apply the LTCC process. The glass-ceramics of diopside base with no Al 2O 3 added had the highest thermal conductivity of 2.372 W/m °C among all specimens fabricated in this study.

  13. Effect of active component addition and support modification on catalytic activity of Ag/Al2O3 for the selective catalytic reduction of NOx by hydrocarbon - A review.

    PubMed

    More, Pavan M

    2017-03-01

    The effect of active component addition and support modification of Ag/Al2O3 has been reviewed to examine their contribution to HC-SCR of NOx. This review has depicted the possible mechanisms of reduction of NO by hydrocarbon using metal/metal oxide doped Ag/Al2O3. The addition of second metal results in the maximum formation of well dispersed Agn(δ+) clusters. Specifically, addition of Au improves the low-temperature activity of the catalyst. However, the role of second metal also depends on the pretreatment to the catalyst and nature of the reductants. The support modification of Ag/Al2O3 by the addition of different metal oxides has also been reviewed. Modification by MgO showed improvement in activity besides sulfur tolerance. In situ DRIFT study demonstrates that the modification by MgO leads to the inhibition of sulfate formation of Ag and Al2O3. Enhancement in activity after second metal addition and support modification attributed to the synergistic effect and improved surface properties of Ag/Al2O3 catalyst.

  14. Experimental and theoretical investigation of effect of spacer arm and support matrix of synthetic affinity chromatographic materials for the purification of monoclonal antibodies.

    PubMed

    Zamolo, Laura; Salvalaglio, Matteo; Cavallotti, Carlo; Galarza, Benedict; Sadler, Chris; Williams, Sharon; Hofer, Stefan; Horak, Jeannie; Lindner, Wolfgang

    2010-07-29

    The aim of this study was to elucidate the influence of each material component-the support, the spacer, and the surface chemistry-on the overall material performance of an affinity type purification media for the capture of immunoglobulin G (IgG). Material properties were investigated in terms of an experimental evaluation using affinity chromatography as well as computer modeling. The biomimetic triazine-based A2P affinity ligand was chosen as a fixed point, while spacer and support were varied. The investigated spacers were 1-2-diaminoethane (2LP), 1,3-propanedithiol (SS3), 3,6-dioxo-1,8-octanedithiol (DES), and a 1,4-substituted [1,2,3]-triazole spacer (TRZ). The support media considered were the agarose (AG) resins, PuraBead, the polyvinylether, Fractoprep, the polymethacrylate, Fractogel, and the porous silica, Fractosil. All materials were tested with pure IgG standard solution, with a mock feed solution as well as real cell culture supernatant. The interaction between IgG and A2P linked through the investigated spacers to AG was studied using molecular dynamics. The effect of a modification of the support chemical structure or of the protein-ligand binding site on the material performances was studied through target oriented simulations. Dynamic binding experiments (DBC) revealed that the performances of materials containing 2LP spacers were significantly decreased in the presence of Pluronic F68. The simulations indicated that this is probably determined by the establishment of intermolecular interactions between the 2LP charged amino group and the ether oxygen of Pluronic F68. The spacer giving the highest IgG dynamic binding capacity when Pluronic F68 was present in the feed was TRZ. The simulations showed that, among the investigated spacers, TRZ is the only one that prevents the adsorption of A2P on the support surface, thus suggesting that the mobility and lack of interaction of the ligand with the support is an important property for an affinity

  15. Mental retardation and Ullrich-Turner syndrome in cases with 45,X/46,X, +mar: Additional support for the loss of the X-inactivation center hypothesis

    SciTech Connect

    Cole, H.; Huang, B.; Brown, J.; Howard-Peebles, P.N.; Black, S.H.; Jackson-Cook, C.; Salbert, B.A.; Febles, O.R.; Stevens, C.A.

    1994-08-15

    Four cases having mosaicism for a small marker or ring [45,X/46,X,+mar or 45,X/46,X,+r] chromosome were ascertained following cytogenetic studies requested because of minor anomalies (cases 1, 3, and 4) and/or short stature (cases 2 and 4). While all 4 cases had traits typical of Ullrich-Turner syndrome (UTS), cases 1, 3, and 4 had manifestations not usually present in UTS, including unusual facial appearance, mental retardation/developmental delay (MR/DD) (cases 3 and 4), and syndactylies (case 1). Using fluorescence in situ hybridization (FISH), each of the markers in these 4 cases was identified as having been derived from an X chromosome. Replication studies demonstrated a probable early replication pattern for the mar/r(X) in cases 1, 3, and 4, while the marker in case 2 was apparently late replicating. To date, 41 individuals having mosaicism for a small mar/r(X) chromosome have been described. Interestingly, most of the 14 individuals having a presumedly active mar/r(X) demonstrated clinical findings atypical of UTS, including abnormal facial changes (11) and MR/DD (13). MR was noted most frequently in those cases having at least 50% mosaicism for the marker or ring. In contrast, atypical UTS facial appearance or MR/DD was not noted in 14 of the 16 cases with UTS who carried a probable late replicating marker or ring. In conclusion, although the phenotype of 45,S/46,X, mar/r(X) individuals appears to be influenced by the genetic content and degree of mosaicism for the mar/r(X), the most significant factor associated with MR/DD appears to be the activity status of the mar/r(X) chromosome. Thus, our 4 cases provide further support for the hypothesis that a lack of inactivation of a small mar/r(X) chromosome may be a factor leading to the MR and other phenotypic abnormalities seen in this subset of individuals having atypical UTS. 46 refs., 6 figs., 3 tabs.

  16. Food additives

    MedlinePlus

    ... or natural. Natural food additives include: Herbs or spices to add flavor to foods Vinegar for pickling ... Certain colors improve the appearance of foods. Many spices, as well as natural and man-made flavors, ...

  17. Nonmetals Test and Evaluation. Delivery Order 0003: Fuel System Materials Compatibility Testing of Fuel Additives for Reducing the Amount of Small Particulate in Turbine Engine Exhaust

    DTIC Science & Technology

    2005-10-01

    JAMES J. MAZZA MARY ANN PHILLIPS Team Lead Chief Adhesives, Composites, and Elastomers Team Materials Integrity Branch Materials...P-24441 (Epoxy Polyamide ) Pencil Hardness Unaged 7d/200°F/JP-8+100 (Control) 7d/200°F/Control + #1 (RXP) 7d/200°F/Control + #2...Description Test Conditioning Results MIL-P-24441 (Epoxy Polyamide ) Taber Test (Wear Index) Unaged 7d/200°F/JP-8+100

  18. Exploring the Options. Curriculum Documents and Support Materials for the General Curriculum Options Stream of the Certificates of General Education for Adults.

    ERIC Educational Resources Information Center

    Johnson, Marlene, Ed.; Brearley, Laura, Ed.

    This document contains detailed curriculum outlines and teacher support materials for the General Curriculum Options (GCO) stream of the Certificates of General Education (CGE) for Adults in Victoria, Australia. The following topics are discussed in the introduction: purpose of the guide, details of GCO subject areas, accreditation framework and…

  19. The effect of biomass immobilization support material and bed porosity on hydrogen production in an upflow anaerobic packed-bed bioreactor.

    PubMed

    Fernandes, B S; Saavedra, N K; Maintinguer, S I; Sette, L D; Oliveira, V M; Varesche, M B A; Zaiat, M

    2013-07-01

    The aim of this study was to investigate the effect of the support material used for biomass attachment and bed porosity on the potential generation of hydrogen gas in an anaerobic bioreactor treating low-strength wastewater. For this purpose, an upflow anaerobic packed-bed (UAPB) reactor fed with sucrose-based synthetic wastewater was used. Three reactors with various support materials (expanded clay, vegetal coal, and low-density polyethylene) were operated for hydraulic retention time (HRT) of 0.5 and 2 h. Based on the results obtained, three further reactors were operated with low-density polyethylene as a material support using various bed porosities (91, 75, and 50 %) for an HRT of 0.5 h. The UAPB reactor was found to be a feasible technology for hydrogen production, reaching a maximum substrate-based hydrogen yield of 7 mol H₂ mol(-1) sucrose for an HRT of 0.5 h. The type of support material used did not affect hydrogen production or the microbial population inside the reactor. Increasing the bed porosity to 91 % provided a continuous and cyclic production of hydrogen, whereas the lower bed porosities resulted in a reduced time of hydrogen production due to biomass accumulation, which resulted in a decreasing working volume.

  20. Au-NiCo2O4 supported on three-dimensional hierarchical porous graphene-like material for highly effective oxygen evolution reaction

    PubMed Central

    Xia, Wei-Yan; Li, Nan; Li, Qing-Yu; Ye, Kai-Hang; Xu, Chang-Wei

    2016-01-01

    A three-dimensional hierarchical porous graphene-like (3D HPG) material was synthesized by a one-step ion-exchange/activation combination method using a cheap metal ion exchanged resin as carbon precursor. The 3D HPG material as support for Au-NiCo2O4 gives good activity and stability for oxygen evolution reaction (OER). The 3D HPG material is induced into NiCo2O4 as conductive support to increase the specific area and improve the poor conductivity of NiCo2O4. The activity of and stability of NiCo2O4 significantly are enhanced by a small amount of Au for OER. Au is a highly electronegative metal and acts as an electron adsorbate, which is believed to facilitate to generate and stabilize Co4+ and Ni3+ cations as the active centres for the OER. PMID:26996816